Even apparently simple choices, like selecting a dessert in a pastry shop, involve options characterized by multiple motivationally relevant attributes. Neuroeconomic research suggests that the human brain may track the subjective value of such options, allowing disparate reward-predictive information to be compared in a common currency. However, the brain mechanisms involved in identifying value-predictive features and combining these to assess the value of each decision option remain unclear. Here, we review recent evidence from studies of multi-attribute decision-making in people with focal frontal lobe damage and in healthy people undergoing functional magnetic resonance imaging. This work suggests that ventromedial and lateral prefrontal cortex and orbitofrontal cortex are important for forming value judgments under conditions of complexity. We discuss studies supporting the involvement of these regions in selecting among and evaluating option attributes during value judgment and decision-making and when learning from reward feedback. These findings are consistent with roles for these regions in guiding value construction. They argue for a more nuanced understanding of how ventral and lateral prefrontal cortex contribute to discovering and recognizing value, processes that are required under the complex conditions typical of many everyday decisions. Certain regions of the frontal lobes—notably the ventromedial prefrontal cortex (vmPFC) and orbitofrontal cortex (OFC)—respond to the values of many different kinds of stimuli . In the lab, such values typically are quantified in dollars in bidding tasks or as Likert scale ratings. This relatively parsimonious model has been very successful in explaining behavior in many different settings. It has even been applied in algorithms that can learn to perform complex tasks like Atari video games that require maximizing an objective reward (points)stimuli . Such fiThough elegant, this solution skips over how a buttercream-frosted dessert is converted to a discrete value. Recent work has begun to address the brain processes involved in arriving at subjective value estimates. These studies have examined how the brain notices value-predictive features and learns about and constructs values for the multi-feature objects that are the typical targets of our everyday choices. This line of investigation suggests that values of complex options are not so much carefully calculated as cobbled together or, under some conditions, inferred holistically from a rich slew of perceptual, mnemonic, and hedonic evidence. In this brief review, we will highlight recent functional magnetic resonance imaging (fMRI) and focal lesion studies (in humans) addressing the formation of values for multi-attribute options, whether based on subjective assessment or external goals or learned from reward feedback.Much as the history of the Roman Empire can be deciphered from the disparate sources of the limestone and marble that make up its ruins, so too “value” can be deconstructed. Breaking complex options down into their component, value-predictive parts can provide insight into how the brain represents information about the individual elements that contribute to value and how (and where) that information is brought together. This reverse-engineering approach has been applied to diverse decision options: photographs of politicians, familiar and novel foods, artwork, and pseudo-objects.6. This literature has broadly indicated that vmPFC encodes values independent of stimulus category7. In contrast, OFC value signals appear to be bound more to the lower-level features or attributes of options9. Together, these data are consistent with the notion that vmPFC is involved in integrating information from diverse sources to construct an overall representation of option values.Functional imaging has found that information about the features or identity of stimuli such as foods, odors, and trinkets is encoded in OFC but that the vmPFC represents a more general value code10. Likewise, in a separate study, participants with VMF damage systematically under-weighted some aspects of artwork, such as emotionality, but relied to a similar degree on simpler, visually perceptible attributes such as concreteness and visual balance in comparison with control groups11.If vmPFC is critical to developing a common currency value representation from multiple attribute-values, damage to this region should disrupt the ability to combine the values of individual attributes. We observed that patients with damage to the ventromedial frontal lobe (VMF) (subsuming the vmPFC and OFC) made reliable value estimates of complex stimuli but to arrive at those estimates drew on information that was different from that of healthy and frontal lobe–damaged controls. For example, those with VMF damage under-weighted “competence” but relied on “attractiveness” to a similar degree when making decisions about which political candidates to vote for12, implying a role in such a constructive process. We recently found evidence that VMF damage specifically disrupts the ability to choose between multi-attribute pseudo-objects (“fribbles”13) when their values were predicted by the conjunction of two attributes. In contrast, such patients were able to make correct choices when values could be “summed up” on the basis of the values of individual attributes14.These observations suggest a more nuanced perspective on the role of vmPFC in value judgment. Why do VMF-damaged patients neglect some attribute-values while reliably drawing on others? One possibility is that these attributes depend on latent information built up from conjunctions of simpler, more directly observable features. For example, determining the emotionality of artwork could depend on putting together information about the expressions of the characters with the circumstances in the scene. Both the hippocampus and medial frontal cortex have been implicated in inferring values for novel conjunctions of food ingredients17. In such cases, decision-making might involve prospective simulation of outcomes that depends on the hippocampus20. Indeed, lesions to the medial temporal lobe and hippocampus were recently shown to lead to slower, more stochastic choices between foods, consistent with a noisier decision process21. Notably, we found that VMF damage did not affect choice stochasticity or the reliability of reported preferences in a similar choice task using artwork22. One possible explanation of the lack of effect of VMF damage in this task, compared with food choices, is that the value of art is assessed on directly observable  information and does not require prospection or construction of values from information in memory.In many cases, value may be built up from information that is not directly observable but rather recalled from memory, such as sensory experiences with food items. Several findings from the fMRI literature are consistent with this perspective, demonstrating that reactivation of prior reward associations can influence future decision-making, even in independent tasksper se than on its role in organizing preferences on the basis of recalled outcomes from past choices. Although VMF damage has been found to consistently increase transitivity errors during preference-based choice in several studies 25, this region is not necessary for the formation of coherent, transitive preferences . Damage to the hippocampus or VMF was recently shown to affect transitive inference of paired associates in humans, implying a shared role in inferring relations between options on the basis of episodic memory more generally27. Thus, the hippocampus and vmPFC may work together to stabilize decision-making based on an inferred transitive ordering of options.The effects of VMF damage on preference-based choice may depend less on the importance of this region for forming valuesAbove, we focused on how value judgments may be constructed in relatively unconstrained settings from mnemonic, conceptual, and perceptual evidence. In this section, we discuss how contextual demands act to shape this process. More often than not, values must be adaptively tailored in response to current goals. For example, the values of potential options in a store might change if you were choosing something for yourself or for your grandmother. Identifying relevant attributes on the basis of such goals and selectively using these during value construction reduce the complexity of the decision space to make such choices tractable. Recent imaging work has uncovered putative mechanisms for selecting attributes on the basis of task demands and examined how neural value signals adapt in response to changing contexts.29 or to choose options with either positive or negative subjective value30. The flexibility of this signal in response to arbitrary task instructions argues that this region can be tuned to the values of options as they relate to higher-order goals rather than their hedonic value independent of task.Value signals in vmPFC are sensitive to the weighting of stimulus attributes on the basis of current goals. The attributes that correlate with vmPFC activity change depending on external contextual demands, such as instruction to focus on taste or health attributes of foodset al.31 (2013) showed that connectivity between vmPFC and the fusiform and posterior superior temporal gyri reflected the contributions of perceptual and semantic stimulus attributes to value judgments, respectively. Changes in task goals during value judgment appear to engage lateral PFC and increase connectivity between lateral PFC and vmPFC32. Thus, this circuit seems to be involved in shifting attention to relevant attributes for value judgment, as externally defined within a task.Functional connectivity studies have shed light on how value representations may be altered by shifting demands. This work has shown that interactions between vmPFC and several other regions depend on demands for integrating information from different stimuli during valuation and decision-making. Lim33 took a slightly different approach. They tested whether external demands to focus on specific attributes of social or dietary decisions altered the decodability of these attributes from brain activity measured by using fMRI . While the decodability of these attributes varied with task demands in lateral PFC, all stimulus attributes were decodable within an overlapping area of vmPFC across conditions. This analysis suggests that vmPFC has access to a rich representation of stimulus attributes even as task demands shift, possibly enabling a more dynamic and adaptive representation of stimulus values. In contrast, lateral PFC is more narrowly involved in specifying goal-relevant attributes.A 2018 study by Tusche and HutchersonThe first section of this review focused on how values are built from attributes in unconstrained settings and the second discussed how weights on these attributes are modified depending on goals. A third (related) stream of work in the realm of reinforcement learning addresses how the value-relevance of attributes is discovered through experience.34. In many cases, relationships may be inferred from conspicuous but incidental short-term correlations that have no bearing on the underlying causal structure of these associations. Think of the problem gambler who has come to believe that a rattling sound at the base of a slot machine predicts a jackpot rather than a loose screw. Indeed, low-level features, such as brightness, volume, or contrast, can give certain attributes greater assumed relevance when inferences are drawn about such relationships. In conditioning tasks, perceptually salient cues are more easily trained and can “overshadow” other predictors35. Visual saliency biases decision-making independent of expected value37, indicating that these low-level features can exert a powerful influence on value construction.The large space of potentially value-relevant features in the natural environment poses a challenge to making appropriate inferences about the relationships between stimuli and outcomes in the real world39. Recent work has indicated that VMF is important for guiding attention to reward-predictive features on the basis of outcome history. We found that people with VMF damage had less of a bias to attend to a feature that was incidentally paired with reward in a visual search task, compared with healthy and frontal-damaged controls40. Functional imaging has also implicated vmPFC in boosting credit for reward-predictive cues, similarly implying a role in boosting the gain on learning feature–reward associations based on their predictive history41.Directing attention to stimulus features that are predictive of rewards can effectively bootstrap the learning process by narrowing the space of features to consider in constructing option values42. In an analogous task, vmPFC was found to encode the attentionally weighted average of the reward value of option features while switches of attention between dimensions were associated with increased activity within the frontoparietal attention network43. In a similar multidimensional learning task, we tested how frontal lobe damage affected learning when participants were informed (accurately) that one low-salience stimulus dimension was predictive of reward but that two other dimensions were not. VMF-damaged participants showed worse learning about the rewardingness of the relevant dimension compared with healthy controls but did not show any increased tendency to credit rewarding outcomes to the irrelevant dimensions. In contrast, left lateral PFC damage caused an increase in the misattribution of outcomes to two  stimulus dimensions44.Examining how participants’ choices track the outcome history of attributes within a given dimension can reveal what participants have inferred about which aspects of the task predict reward. Recent neuroimaging studies have used multidimensional learning tasks to identify the regions engaged in learning attribute relevance. These studies have found that regions within the frontoparietal attention network, including lateral PFC, are engaged when identifying predictive, relevant dimensions based on feedback history45. This “spread-of-effect” phenomenon was shown to be exaggerated in non-human primates with OFC lesions46, evident in a blurring of the influence of recent choices and outcomes. More recently, convergent evidence from studies of human and non-human primates with frontal lesions has indicated that damage to anterior ventrolateral PFC or lateral OFC particularly increases this failure to assign credit to the appropriate choices48. Functional imaging in humans similarly has pointed to lateral OFC or ventrolateral PFC as being particularly important for credit assignment when choice–outcome associations must be maintained over a delay or intervening trials49. These data suggest that lateral PFC or OFC may play a similar role in specifying the features relevant to predicting outcomes in the temporal domain and the visual domain.Just as faulty inferences might be drawn about the associations of outcomes with visual stimulus features, so too can outcomes be attributed to events that were temporally proximate but not causally relatedRecent human lesion and functional imaging work has identified frontal lobe regions and related circuits that are involved in dynamically constructing the values of complex stimuli in preference-based choice, whether based on current goals or in the course of learning. The lesion results help to constrain interpretation of fMRI in healthy people, arguing for a more nuanced and specific role of VMF and lateral PFC in these processes. VMF damage leads to under-weighting specific higher-order stimulus attributes during value judgment and disrupts attention to relevant features that are predictive of rewards in the long-term during learning. In contrast, lateral PFC is involved in arbitrating between stimulus dimensions, in particular when task demands and contextual factors specify a subset of attributes relevant to a choice.52.These findings open up new questions. For example, what is the role of VMF in incorporating complex attributes during decision-making and value judgment? One possibility is that this region is necessary for forming values out of non-linear conjunctions between attributes . Another is that VMF damage disrupts the ability to construct a latent, holistic representation of conceptual information about stimuli, leading these patients to rely instead on attribute-value representations at the level of discrete elements. The latter explanation would be broadly in line with ideas that OFC is representing information about latent task states to inform decision-making and learning43. Whereas some data argue that lateral PFC acts on vmPFC to impose contextual demands on the attributes used in making value judgments29, other findings support a role for vmPFC in representing “schematic” information about a task that is passed to lateral PFC to define the template for cognitive control53. The direction of information flow between regions may depend on the observability of contextual cues, where directly observed contextual information may engage lateral PFC54 whereas hidden changes in task state that must be inferred from schematic knowledge may rely on vmPFC or OFC55.What is the nature of the interaction between lateral PFC and vmPFC during value construction? Communication between these regions appears to depend on decisions to switch or maintain attention on particular stimulus dimensionsWe have focused here on the neural implementation of value construction and the particular contributions of regions of the frontal lobes to solving this problem to allow choices between the complex objects that we face in our everyday choices. However, a full account of how the brain builds holistic value representations will require a better understanding of the dynamics between frontal lobe regions and the brain areas that carry the perceptual, conceptual, and mnemonic evidence that are the building blocks of this process. Such work will have broad importance in better understanding economic and social decision behaviors and addressing how those decision processes may go awry in neurological and psychiatric illnesses.


While the association between general housing and mental health has been well documented, little is known about the mental health outcomes of house sharing. As shared housing has been viewed as an economically and socially viable housing option for young adults, a broader understanding of how shared housing affects the residents’ quality of life, including mental health, is needed. In this context, this study aims to provide empirical evidence about the relationship between mental health and house sharing after controlling for residents’ self-selection. We conducted a survey of 834 young single adults living in shared housing and non-shared housing in Seoul, Korea. Then, to control for residential self-selection, we applied the residential dissonance framework. The main findings of this study were two-fold: first, house-sharers with a positive attitude toward shared housing were more likely to respond that their mental health status improved after they started residing in shared housing; second, if young adults are forced to live in shared housing, this could increase the potential risk of social dysfunction of house-sharers. Based on these findings, we suggest policy measures for shared housing, including pre-occupancy interviews, resident behavior codes, and fostering a livable dwelling environment to ensure a healthier life in shared living arrangements. Along with the increase in the number of single-person households and the proliferation of the sharing economy, shared housing where unrelated adults live together has re-emerged as a viable economic and social housing option for young adults . House sHome-sharing provides social support from other sharers and caretaking for each other . Oh and The relationship between housing and mental health is well documented in the existing literature ,14. SwopThe mental health of house-sharers can be understood based on the three key mediating factors identified by Evans et al.  and BarrDespite the accumulated knowledge on the impact of the house environment on residents’ mental health and the efforts to explore how shared housing is linked to mental health, empirical evidence for their causal relationship is surprisingly scarce. Ahrentzen  examinedUnderstanding the needs of single young adults in the context of shared housing is essential for solving the housing challenges currently facing this demographic group . SimilarTo answer these research questions, we conducted a survey of 834 single young adults in Seoul, Korea, 334 living in shared housing and 500 living in non-shared housing) and analyzed their perception of shared housing, current residence characteristics, and mental health status. Based on quantitative analysis, this study provides empirical evidence for the effect of house-sharing on mental health. The next section explains how the analytical variables to measure mental health were constructed and the analytical strategy used to address the self-selection issue. This is followed by the results section, then, the main findings are discussed and some policy and managerial suggestions for shared housing are given.All the data and variables used in the analysis were obtained from the survey summarized in The survey questionnaires included socio-demographic attributes, current residence attributes, and other indicators to represent the quality of life including mental health-related measures among young single-person households. A description of each of these variables is presented in The procedure for data analysis was as follows. First, the overall characteristics of shared housing residents were presented using descriptive statistics. Next, we compared the indicators for the mental health status of shared housing and non-shared housing residents using graphs. Further, by applying the residential dissonance framework explained in the following paragraphs, logistic regression models were constructed to examine whether the differences in mental health status originate from current shared living experiences when residents’ self-selection was addressed. Last, in the discussion section, we suggest some explanations and links for the impact of shared living on mental health, mainly focusing on the psychosocial processes suggested by Barratt et al. .To provide more robust empirical evidence of a causal relationship between shared living and mental health outcomes, residents’ self-selection issues should be addressed methodologically . It is dConsonant shared housing residents (CS): those who reside in shared housing and have positive attitudes toward sharing residential space.Dissonant shared housing residents (DS): those who reside in shared housing and have negative attitudes toward sharing residential space.Dissonant other housing type residents (DO): those who reside in other (non-shared) residential types and have positive attitudes toward sharing residential space.Consonant other housing type resident (CO): those who reside in other (non-shared) residential types and have negative attitudes toward sharing residential space.The residential dissonance framework assumes that there could be a considerable mismatch between preferred residence type and actual residential choice  for several reasons, such as budget constraints, which force one to live in a certain residence . Based oThis study measured residential preference as to whether the residents had a positive or negative attitude toward shared living. In more detail, the attitude toward shared living was calculated as the average of responses to eight survey items on a four-point Likert scale that asked for the perception on shared housing. The items were as follows: “it helps to save housing cost,” “it helps to build a new social relationship,” “it helps to reduce loneliness,” “it provides better location and facilities,” “it provides better safety and security,” “it does not guarantee privacy,” “it has concerns about social conflicts with housemates,” and “it has noise and cleanliness issues.” Considering the reverse scoring in the last three questions, if the average value was higher than the median value of the four-point Likert scale (2.5), we assumed that the resident had a positive attitude toward sharing residential space. In this way, by differentiating between those who had a preference to live in a certain housing type and others who did not, the living outcome from shared living can also be categorized as the impact of a shared housing environment or the impact of residential preference. For example, if both consonant and dissonant shared housing residents showed better mental health status than both consonant and dissonant non-shared housing residents, it indicated that the living experiences under the current shared housing environment substantially enhanced the residents’ mental health regardless of whether they chose or were forced to live there. On the contrary, there could be a case where only consonant shared housing residents and dissonant non-shared housing residents show enhanced mental health outcomes compared to other resident types. In this case, it is hard to say that the shared living experiences enhanced the residents’ mental health status. Rather, it indicates that mentally healthy people might prefer shared housing. The opposite situation is also possible. As suggested by Green and McCarthy , shared About 90% of shared housing residents and 62% of non-shared housing residents responded that they were paying rent monthly. In the same context, the average residence period of house-sharers was about one and a half years, which was relatively shorter than two years and four months for non-house sharers. In addition, contrary to what is generally believed, the cost of living in shared housing was not significantly lower than other housing types .The residents in shared housing were more likely to report that their mental health status had improved since they started residing in their current residence, but they had nearly similar ratios to those who showed signs of potential disorder in mental health status. Extroverted people also tended to choose shared housing more than introverted people. However, it should be noted that there exists a dissonance in current residence so that the perception, behavior, and resulting living outcome of current residents might differ based on whether the resident was consonant or dissonant. Thus, in the next section, using the residential dissonance framework, we will discuss the results on whether shared housing residents showed substantially better or worse mental health status than others, and whether the difference in mental health remained statistically significant after controlling for other factors using a logistic regression model.The mental health status for each indicator by residential dissonance type using the one-way analysis of variance (ANOVA) test assuming non-equal variance are presented in In terms of mental distress, there were significant differences in potential disorder in social dysfunction based on residential dissonance type, while this was not the case for potential disorder in anxiety and depression. More specifically, the differences in potential disorder in social dysfunction showed a similar value to that of mental health status improvement, except for its direction. In other words, the preference for shared housing was negatively correlated with the ratio of potential disorder in social dysfunction, as it was positively correlated with the ratio of mental health status improvement.To further examine whether the above differences would remain statistically significant when holding other variables constant, we constructed three logistic regression models where the dependent variables were the mental health indicators shown in On the other hand, several factors were found to have a significant impact on a potential disorder in social dysfunction. Specifically, those in the youngest age group (20–24), satisfied with their current housing environment, or who had an extroverted personality were less likely to show signs of mental disorder in social dysfunction. Most importantly, the dissonant shared housing residents (DS) had a significantly higher probability of being socially dysfunctional. These results are consistent with the findings of Green and McCarthy , Rugg 99, and OrThe main findings of this study are two-fold: first, the consonant shared housing residents generally showed a better mental health status than the other non-shared housing residents with regard to mental health improvement; and second, there is a possibility that shared housing residents can suffer from the disorder in social dysfunction if they do not have a preference for shared living. In terms of the association between shared living and mental health outcomes, Barratt et al.  proposedTo compare psychosocial mitigating processes between consonant and dissonant shared housing residents, we measured three constructs for each process in reference to Barratt et al.’s  configurShared housing has maintained its popularity as a policy option for affordable housing supply. In the UK, the HomeShare UK scheme was launched in 1993 to improve well-being  by reducing loneliness and isolation and there were 27 HomeShare providers in 2017 . The KorThe findings from this study have several practical implications for the allocation and management of shared housing as follows. First, the study shows that uncontrollable environments such as unwanted social interaction with strangers or poor housing maintenance conditions, and residential insecurity may result in an unhealthy mental status. Thus, a pre-occupancy interview before moving into a shared house could be helpful to further promote improvement in mental health status and to mitigate the risk of disorder in social dysfunction of house-sharers. The interview might inform or filter dissonant shared housing residents who might not want to live there. Providing an independent affordable housing option for those who do not prefer unintended social interaction or community activities to prevent mental distress should be considered, too. Second, it shows that the behavior of other tenants seems to be related to mental health status. As Nasreen and Ruming  found, tThis study provides empirical evidence regarding the relationship between house-sharing and mental health. To function as a sustainable housing option presently and in the future, a broader understanding of the living outcomes of shared housing, including mental health, are necessary to build more successful and appropriate policy measures. Similar to this study, which extends the knowledge of how shared housing affects the mental health of its residents, the socio-economic and health outcomes of shared housing should be explored in different cultural and country contexts to provide more generalizable findings. To provide more robust findings regarding health outcomes and residential environments, pre-and post-test research design, and an understanding of the role of psychosocial mitigation factors should be employed. This study presents several theoretical relationships between living in shared housing and mental health outcome. As Kenyon and Heath  noted, f


Brassica species demonstrating variation in both defensive and reproductive traits along an agricultural land use gradient. Our framework illustrates the potential for plant adaptation under land use change and predicts how defense and reproduction trait expression may shift in low diversity landscapes. We highlight areas of future research into plant population and community effects of land use change.In the Anthropocene, more than three quarters of ice-free land has experienced some form of human-driven habitat modification, with agriculture dominating 40% of the Earth’s surface. This land use change alters the quality, availability, and configuration of habitat resources, affecting the community composition of plants and insects, as well as their interactions with each other. Landscapes dominated by agriculture are known to support a lower abundance and diversity of pollinators and frequently larger populations of key herbivore pests. In turn, insect communities subsidized by agriculture may spill into remaining natural habitats with consequences for wild plants persisting in (semi) natural habitats. Adaptive responses by wild plants may allow them to persist in highly modified landscapes; yet how landscape-mediated variation in insect communities affects wild plant traits related to reproduction and defense remains largely unknown. We synthesize the evidence for plant trait changes across land use gradients and propose potential mechanisms by which landscape-mediated changes in insect communities may be driving these trait changes. Further, we present results from a common garden experiment on three wild  Agriculture now represents the largest anthropogenic biome on the planet, occupying over a third of the earth’s ice-free land . Loss ofThe coevolution of plants and insects has resulted in both an evolutionary arms race of defense and counter defense as well as a sweeping reliance on insects for reproduction. Given that both antagonistic and beneficial insects are major agents of selection, frequently on similar plant traits, it is likely that changes in the insect community driven by land use change alter plant trait evolution . AdditioCapsella bursa-pastoris) were allowed to self-pollinate, we found that plants sourced from populations surrounded by natural land cover, produce more and/or heavier seeds than populations surrounded by more agricultural land  and ce versa . Althougce versa . Increasce versa . Relief ce versa .Solidago altissima, populations resulted in lower mean resistance to a major specialist herbivore, the goldenrod leaf beetle, Trirhabda virgata, but had no effect on the resistance to an herbivore uncommon in this system, the fall armyworm (Spodoptera frugiperda)  . Neverthper se, rather than the increased production of defensive compounds can provide a moving target for foraging herbivores (moving target hypothesis)  . (IV) Heothesis)  or neighothesis) . The plaOverall, changes in the herbivore community  can have short-term ecological effects due to the inducibility of metabolic changes in response to herbivory or they can have intermediate-term microevolutionary effects on the population genetic structure that feeds back to the ecological interactions . CorrelaHelianthus annuus texanus) that were farther away from cultivated sunflowers (H. annuus), than those growing next to cultivated sunflowers (Helicoverpa armigera) on cotton, but also on other crops such as corn, peanuts and other vegetables attacked by this pest , which is a known pest of coffee was found to be feeding on the wild rubiaceae, Bertiera zaluzania, with negative effects on the plant’s fitness (Diabrotica barberi and D. virgifera) in wild sunflowers. The wild sunflowers had more floral damage and decreased seed set when they were close to the edges of the corn fields, due to a combination of the life history of the pest and the timing of the crop. When the adults emerge in July they feed on corn silks and immature ears, but once the crop is mature and dry they no longer prefer it and will shift to the wild sunflowers that are blooming at that time. Similarly, wild mustard (Sinapis arvensis) experiences higher herbivory from the pollen beetle (Meligethes aeneus), a pest of canola (Brassica napus), immediately following canola bloom in areas with higher canola cover  but also very likely through changes in herbivore traits, that have not been as clearly documented but see . HoweverBarbarea vulgaris from sites of varying landscape composition across the Finger Lakes region in New York State, United States. Plants were grown in a greenhouse common garden and bioassays were conducted with 3-day old Trichoplusia ni (Noctuidae) caterpillars to evaluate resistance on 3-week-old plants  pollinators are shown to impose selection for increased floral size in urban, but not rural landscapes  information with their neighbors which allowed for a more even distribution of herbivory in the plant population and thus minimizing the damage each individual plant receives  and so, presumably increase predation pressure on herbivores and, consequently, increase plant fitness . It is p effects . Similarreceives . While tSolidago altissima study to increase information transfer between plants in populations of elevated herbivory and was interpreted as a convergence of chemical language  strength of inducibility , (II) induced changes in composition , and (III) changes in relative similarity of VOC bouquets among plants of the same population . The latlanguage . A simillanguage . Thus, wAlthough the direct effect of natural enemies on plant selection remains an area to be studied, there is clear evidence that land use change impacts natural enemy communities . Land usInterestingly land use change can differentially affect natural enemies depending on their extent of specialization and invasiveness. For example, in prairie systems in Michigan and Wisconsin, the abundance of native lady-beetles decreased, while the abundance of exotic lady-beetles did not change with increasing annual agricultural cover . For netAn increase in natural enemy abundance related to land use change is expected to occur when the surrounding agricultural matrix provides more resources such as hosts, overwintering sites, pollen and nectar to natural enemies than natural habitats . For exaThe scenarios in which natural enemies prefer and thrive in agricultural matrices could lead to permanent or temporarily different outcomes for wild plants. If natural enemies prefer agricultural fields over adjacent natural areas, there could be a reduction in natural enemies and biological control for wild plants. This reduction could be permanent or limited in time if these natural enemies spill back and even increase the number of natural enemies in natural areas. Empirical work has shown that the adjacent crop habitat , and manPhytomyza ilicis, was higher than in woodland interiors  and the associated increase in self-compatibility and autonomous selfing. This suggests that altered selection by herbivores can strongly affect plant defense expression and so the interaction of plants with pollinators  land use affects an insect interactor, (2) the interactor affects the plant traits, and (3) land use affects the plant traits via changes in the interactor. These studies would need to be repeated for multiple systems and sites to answer the following question: Are there broad patterns across systems and insect groups?2.Eco-evolutionary feedback loops in plant communities: Determine how changes in plant traits lead to an eco-evolutionary feedback loop between the insect community and the plant community driving change beyond the plant population.3.Land use change and plant indirect defenses. How does land-use change affect plant indirect defenses? Is there conflicting selection on plant indirect and direct defenses or do they function synergistically? What is the role of abiotic factors like pesticides and fertilizer in mediating the relationship between plants and natural enemies?4.Land use change and plant population genetics. How does land use change affect plant populations genetics? To what extent can variation be explained by plasticity and maternal effects? Further, selection experiments along the land-use change gradients are equally important to determine if these changes in traits are adaptive.Though we have highlighted numerous challenges in disentangling plant-insect interactions across landscapes, we present land use gradients as a unique opportunity to use modified landscapes as a natural experiment. The magnitude of land use change creates an experimental framework that can be utilized in systems across the globe. Experiments within this framework can reveal the selection pressure exerted by different organisms, the resulting effect on plant fitness, and how the relative importance of each interactor changes with landscape mediated changes in insect community composition. We are not aware of any one study that simultaneously examines the following three steps linking land use change to the evolution of plant traits via some insect interactor: (1) land use affects the interactor, (2) the interactor affects the plant traits, and (3) land use affects the plant traits via changes in the interactor. While descriptive studies are a crucial starting point, selection experiments are needed to establish a causal link and to test the role of maternal effects. We propose artificial selection experiments in which individuals from the extreme ends of the land use gradient are crossed and the offspring self-pollinated to segregate traits. The large variation in traits of these F2 populations can be used to evaluate which traits are selected for in given environments and which insect interactors are likely important agents of selection. Pollinator and herbivore exclusion treatments would be necessary to disentangle the role of each group. Further, abiotic factors associated with land use change such as pesticide and fertilizer runoff are also known to impact wild plant communities . These fThe conversion of natural habitats to human-modified landscapes disrupts the stable species interactions that evolved in these landscapes. Unlike natural disturbances where succession restores many pre-disturbance species interactions, human-modified landscapes are maintained in a modified state. Through this review and our own results, we have collected evidence suggesting that altered communities of pollinators, herbivores, and natural enemies occupy these modified landscapes and that each of these insect groups can act as a selective force. Thus, we hypothesize that wild plants are experiencing differential selection based on landscape context through interactions with the resulting community of insects. Further studies are needed to examine the outcomes of landscape-mediated selection on individual plant traits and ultimately to understand the consequences for wild plant communities on a broader scale.Differential selection on plant traits across the landscape likely has cascading consequences for population and community dynamics driven by evo-eco feedback loops. In each landscape context, the availability of insect interactors depends on whether an insect is able to utilize the modified habitat. Plant trait evolution and changing plant community and population dynamics, in turn, will affect which members of the insect community remain or are added to interact with the plant community. Selection on traits that increase or decrease the attractiveness of a plant population to herbivores and/or pollinators may impact the entire plant community, potentially altering the insect community drawn to a patch and the relative competitive ability of plants within the patch. This may create a feedback loop where plant adaptation reinforces traits in the insect community and patterns of insect availability. There is already evidence that human-mediated land use change is linked to trait filtering in plants and insects, and selection by insects may be one additional mechanism through which this trait filtering is occurring in plants .Through this review we hope to motivate further studies examining the potential for wild plants to adapt with land use change, the outcomes of conflicting selection, and the ultimate consequences for plant fitness and community structure. Future work should examine plant population genetics to establish if observed phenotypic changes represent plasticity or genetic change. Additionally, while many studies suggest the mechanisms by which land use change affects natural plant communities, few actually test these claims. Of all the patterns examined here, the effects of land use change on indirect defenses remains the least studied . Given thttps://doi.org/10.5061/dryad.ncjsxkst4. The data is uploaded to dryad but not publicly available while under review.The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found below: KP and AK conceived the idea of the manuscript. HG and KP collected the data. HS and HG analyzed the data. HS drafted the manuscript to which all authors contributed sections and revisions.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


All established strategies, however, have in common that they focus on circulating cells which are involved in thrombus formation  or recruited to atherosclerotic plaques . In constrast, plaque resident cells like endothelial cells (EC) or vascular smooth muscle cells (VSMC) that initiate and propagate local inflammatory processes are so far rather studied in experimental models. EC for instance, which represent the major barrier between tissues and the blood stream, were successfully targeted experimentally2 but the therapeutic potential of such approaches may be limited due to offsite effects that can be expected in other, non-diseased organs. These limitations can be overcome if we understand how local cells change their phenotype under disease conditions. In MATRICARD, a project funded by the European Research Council under the European Union’s Horizon 2020 research and innovation program within the Starting Grant scheme, we will focus on the role of the extracellular matrix (ECM) as a mediator of communication between different cell types in the vascular wall and the myocardium under inflammatory conditions  Mutations in collagens, elastin and fibrillins were described to be causal in aortic aneurysm formation; 2) Genetic variation in genes encoding collagens, integrins, and matrix metalloproteinases was associated with atherosclerotic diseases; 3) Neointima formation after vascular injury is associated with massive alterations of the ECM including collagens, laminins, and matrix metalloproteinases5. In addition to structural alterations of the ECM, modulation of inflammation by ECM fragmentation has been described. Thrombospondin-1 is an example for an ECM protein with differential functions: whereas its degradation promotes neointima formation via delayed reendothelialization, a loss of thrombospondin-1 does not influence neointima formation secondary to vascular injury6.The ECM was mainly regarded as a microenvironment and scaffold for cells contributing to the bulk, shape and strength of tissues. In recent years, it has been recognized that the ECM is an active key player in the regulation of dynamic processes such as migration, proliferation and differentiation of resident cellsThe goal of MATRICARD is to get a closer look at ECM alterations which occur in acute and chronic cardiovascular inflammation and the downstream effects on other involved cell types. MATRICARD is an interdisciplinary project that will bring together clinician scientists and basic scientists. It is organized in four work packages (WP).7. The combination of high-end microscopy and mass spectrometry furthermore now also allows to investigate the proteome of single cells: Deep Visual Proteomics (DVP) is a technique that was first described in melanoma tissue and uses artificial intelligence-based image analysis to microdissect single cells from tissue sections for ultra-high-sensitivity mass spectrometry8. An application in cardiovascular diseases promises to provide insights on a new level. In WP2, we will investigate the role and the molecular mechanisms of targets identified in WP1. One target is the ECM protease ADAMTS-7 (In WP1, we will explore the molecular changes that occur in acute and chronic inflammation. We will use transcriptome analyses to phenotype resident and recruited cells in different areas of interest. A holistic view and the observation of alterations in the ECM, however, furthermore requires a thorough analysis of the proteome. Fortunately, in recent years proteomics made great progress. It is not only possible to detect proteomic alterations in bulk tissue but also in different compartments. Quantitative detergent solubility profiling enables the analysis of the ECM proteome and has already been established in atherosclerosisADAMTS-7 .9, it was shown to modulate VSMC and EC phenotypes via degradation of different ECM proteins. The exact mechanisms in atherosclerosis remain incompletely understood but targeting ADAMTS-7 nevertheless represents an attractive therapeutic approach: a recent study found that a peptide-based vaccination against ADAMTS-7 was able to beneficially influence atherosclerotic plaque formation and vascular remodeling in mice10. Further ECM proteases but also their downstream targets could be promising candidates for mechanistic exploration. In WP3, we will therefore develop tools that enable us to identify modulators of our proteins of interest which can be used for therapeutic intervention.Originally identified as a risk gene in coronary artery diseaseMATRICARD is an experimental project and our findings will be limited by the artificial nature of experimental models in mice as a model organism. Therefore, it is important to compare findings from such experiments with available human data. The use of large-scale biobanks comprising genetic and phenotypic data of hundreds of thousands of individuals as well as biospecimen from individuals undergoing coronary bypass or carotid surgery for coronary or cerebrovascular atherosclerotic disease represents an excellent opportunity to validate findings and explore future translational approaches.Taken together, the ECM represents a fascinating compartment with dynamic functions. We hope that within the next years, our group will be able to add novel insight into its function and identify novel putative targets to reduce the burden of cardiovascular inflammation and disease.


We conducted a systematic literature review in accordance with the PRISMA protocol on the evidence for the treatment of cartilage damage using human MSC-EVs. Studies examining in vivo models of cartilage damage were included. A risk of bias analysis of the studies was conducted using the SYRCLE tool. Ten case-control studies were identified in our review, including a total of 159 murine subjects. MSC-EVs were harvested from a variety of human tissues. Five studies induced osteoarthritis, including cartilage loss through surgical joint destabilization, two studies directly created osteochondral lesions and three studies used collagenase to cause cartilage loss. All studies in this review reported reduced cartilage loss following treatment with MSC-EVs, and without significant complications. We conclude that transplantation of MSC-derived EVs into damaged cartilage can effectively reduce cartilage loss in murine models of cartilage injury. Additional randomized studies in animal models that recapitulates human osteoarthritis will be necessary in order to establish findings that inform clinical safety in humans.Damage to joints through injury or disease can result in cartilage loss, which if left untreated can lead to inflammation and ultimately osteoarthritis. There is currently no cure for osteoarthritis and management focusses on symptom control. End-stage osteoarthritis can be debilitating and ultimately requires joint replacement in order to maintain function. Therefore, there is growing interest in innovative therapies for cartilage repair. In this systematic literature review, we sought to explore the  Damage to joints through injury or disease can result in cartilage loss, which if left untreated can lead to inflammation and ultimately osteoarthritis (OA)  AND  AND . Following de-duplication, exclusion criteria was applied to studies not written in or translated into the English language. We excluded studies that only performed in vitro experiments. Studies that did not characterize or validate the cell populations as per the recommendations of the International Society for Cellular Therapy (ISCT) for MSC were excluded  statement protocol  tool  models, leading to altered weight-bearing and subsequently generalized OA changes, which includes cartilage loss. These models are reliable, reproducible, and have high disease penetrance. The time-course over which cartilage changes develop is delayed and therefore recapitulates the nature of human disease (Glasson et al., It is important to determine standardized methods of assessing outcomes relevant to cartilage repair. Several studies reported improvements in the macroscopic appearance of cartilage; while macroscopic appearance scoring is predictive of histological scoring (Goebel et al., in vivo to a greater extent than treatment with MSC-EVs alone (Chamberlain et al., In addition to promoting chondrogenesis in chondrocytes, it is likely that EVs contribute to cartilage repair via effects on other cell types. Macrophages are postulated to be a key target for MSC-EVs, with evidence suggesting that EVs cause an M2 phenotype polarization that promotes resolution of inflammation and so promotes cartilage repair (Chen et al., Due to the plethora of pathways through which MSC-EVs can promote cartilage repair, a key step to studying their effects in animal models is to establish the roles of the different bioactive components within EVs. Similarly, outcome measures utilized in studies should complement this. We recommend that cartilage appearance and chondrogenic gene expression should be primary outcomes in addition to quantifiable and clinically relevant functional outcomes such as pain reduction or animal gait analysis. Likewise, it would be beneficial to establish a link between functional and histological outcomes, as the value of assessing histology may otherwise be minimal. In order to establish the optimal way to deliver clinical benefit using MSC-EVs, the most efficient MSC cell source, methodology of cell culture and EV purification should be investigated for the purposes of cartilage repair. Finally, randomized studies in animal models that recapitulates the human disease will be necessary in order to establish a dose-response relationship and therefore clinical safety before we proceed to human trials.The original contributions presented in the study are included in the article/supplementary materials, further inquiries can be directed to the corresponding author/s.KT and WK conceptualized the review manuscript. KT wrote the manuscript under the supervision of FH and WK. KT and AK assembled study data and conducted literature searches. KR and CM conducted data analysis and risk of bias analysis. All authors contributed to editing and approving the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Misregulation of MYC genes, causing MYC overexpression or protein stabilization, is frequently found in malignant brain tumors highlighting their important roles as oncogenes. Brain tumors in children are the most lethal of all pediatric malignancies and the most common malignant primary adult brain tumor, glioblastoma, is still practically incurable. MYCN is one of three MYC family members and is crucial for normal brain development. It is associated with poor prognosis in many malignant pediatric brain tumor types and is focally amplified in specific adult brain tumors. Targeting MYCN has proved to be challenging due to its undruggable nature as a transcription factor and for its importance in regulating developmental programs also in healthy cells. In this review, we will discuss efforts made to circumvent the difficulty of targeting MYCN specifically by using direct or indirect measures to treat MYCN-driven brain tumors. We will further consider the mechanism of action of these measures and suggest which molecularly defined brain tumor patients that might benefit from MYCN-directed precision therapies. The development of massive sequencing efforts and molecular profiling of malignant brain cancer biopsies from patients and the strive to characterize them better has transformed the diagnosis of these tumors –5. The aHere, we will describe the prevalence of MYCN alterations in malignant brain cancer in children and adults. We will also portray current treatment regimens and patient outcomes and reflect on how targeted treatments of MYCN would improve future therapies for the most common and aggressive types of brain tumors. In order to develop such targeted strategies, we must first define what we have learned from the biological properties and regulation of MYCN in normal and malignant cells. We will specifically address what molecular information we can use from appropriate cell systems and animal models of brain cancer in order to develop better MYCN-targeted treatments.Brain cancer as compared to other tumors outside of the central nervous system (CNS) present an obvious hallmark. They reside in a partially protected compartment that implicates difficulties and complications concerning drug delivery and penetrance over the blood-brain barrier (BBB). The difference in childhood and adult tumors is still evident as well as the fact that treatment can affect normal brain development and can cause severe long-term side effects. The translational transfer of basic molecular findings from the bench into reliable, tailored drugs for these patients to the bed-side is thus not always straight-forward and requires careful selection and testing.Brain and other CNS tumors are the most common solid tumors in children and the most common cause of pediatric cancer death. Gliomas are the most common brain tumors in children, with the majority being low-grade gliomas (LGGs). The most frequently diagnosed single histological type of tumor is pilocytic astrocytoma, which accounts for 18% of primary brain tumors in children ages 0–14 years , 10.Meningiomas, pituitary tumors, and malignant gliomas are among the most common primary adult brain tumors  Primary Pediatric high-grade gliomas (pHGGs) account for approximately 17% of all pediatric CNS tumors . pHGGs aDue to its critical role in regulating cell cycle and metabolism, MYC has been found overexpressed in GBM, with a tendency towards correlation of astrocytic GBM grade with the level of both nuclear and cytoplasmic MYC –21. In aIDH1 mutation is a known predictor of response to temozolomide  and convIn malignant glioma with primitive neuroectodermal components (MG-PNET), a rare type of brain tumor that most likely develops from already existing glioma, about half of the patients demonstrate mutually exclusive MYC or MYCN amplifications .MYCN was early found to form extrachromosomal double minutes in neuroblastoma (NB) . Recent CNS embryonal tumors, including medulloblastoma (MB) and atypical teratoid/rhabdoid tumors (ATRT), account for 13.1% of primary CNS tumors in children . Nearly Additionally, a MYC-subgroup has recently been identified in pineoblastoma, a rare but quite frequently metastatic, pediatric brain tumor of the pineal gland with modest overall survival despite intensive therapy . InteresThere is no current international consensus on the treatment of neither pediatric nor adult brain tumors. However, most patients see surgical tumor resection, radiotherapy, and chemotherapy. Factors such as diagnosis, grade, location, tumor dissemination, and age impact how each of these parts are implemented in the treatment plan. Surgical removal of the tumor mass is always included when it is possible to do so. Successful surgery depends on how much of the tumor can be safely resected and is the biggest prognostic factor for overall survival and deciding subsequent radiotherapy and chemotherapeutic regimens.Radiation therapy is often given as a high dose fractioned over several occasions and directed at the primary tumor site. Patients with spinal metastases receive radiation therapy to the entire cranio-spinal axis. For adult brain tumors, radiotherapy is a major part of standard treatment. In children, MB patients have great benefits on survival from irradiation  and evidThe youngest patients with high-grade brain tumors that are not eligible for radiation and/or surgery are especially negatively affected by the lack of efficient and safe chemotherapeutics. Tumor treating fields is a low toxicity, non-invasive, non-pharmacological treatment of both newly diagnosed and recurrent GBM, used in combination with standard therapy. It is electromagnetic fields administered through the skin of the scalp and its arrangement is individualized to optimize effect at the tumor site. As it is suggested to target primarily dividing cells during mitosis and causes DNA damage in cycling cells, normal cells in the brain should be spared . Data alMany chemotherapeutics have been used empirically for decades despite showing substantial effects on prolonging survival of brain tumor patients. On the other hand, targeted therapies for primary brain tumors have of yet not lived up to the expectations and some of these lead to treatment resistance in recurrent tumors. Due to the inability of current treatment options to cure or even extensively prolong survival of patients, both adult and pediatric patients are often enrolled in multinational clinical trials. Careful stratification of patients into correct molecular subgroups and repeated biopsying  could heImmunotherapies in brain cancer is a rapidly emerging field. Checkpoint inhibitors have been intensively tested but unfortunately shown limited efficacy in glioblastoma patients . It is eChimeric antigen receptor (CAR) T cell transfer is an interesting option in pediatric brain tumor patients  as long Finally, dendritic cells are important antigen-presenting cells that express both MHC class 1 and 2 molecules and can stimulate antitumor immune responses. Dendritic cell vaccines  are currThe family of MYC proteins  are basic helix-loop-helix-zipper (bHLHZ) transcription factors, tightly regulated by extracellular growth stimulatory signals and an intricate intrinsic mechanism behind expression, activation, and degradation of MYC proteins Figure 2MYC and MYCN siblings are similar in structure, and can often substitute each other’s functions . MYC proThe transcriptional output signature of MYC is highly dependent on the cellular context. The different MYC family members are very similar but MYCL and MYCN are distinctly expressed in specific tissues  unlike c-MYC which is found expressed in most tissues. MYCN is crucial for normal brain development , 59.cis to trans which increases the affinity for DNA binding and subsequent transcriptional activity of MYC. On the other hand, it also makes it recognizable by glycogen synthase kinase 3 beta (GSK3β), a kinase that will phosphorylate MYC at T58  and threonine 58 (T58) . ConsecuC at T58 . MutatioC at T58 . The E3 C at T58 . In normC at T58 , 66. In MYC proteins play an important role in oncogenesis and progression of tumors and many reports have shown that suppression of MYC or MYCN by genetic means results in growth arrest, induction of apoptosis or senescence leading to tumor regression. Knockdown of MYC even results in regression of brain tumors driven by Trp53 and Pten loss in astrocytic cells .In an attempt to attenuate MYCN expression in NB, Galderisi et al.  utilizedtet-inducible promoter regulates a transgene, can be utilized to turn on and off cancer genes. We have previously utilized this strategy to first demonstrate the role of MYCN in Group 3 MB development and subsequently showed that long-term withdrawal of MYCN results in tumor regression and life-long remission  on the BRDs , 96 in cTargeting the transcriptional machinery is not limited to BET inhibition but there are more traditional strategies using kinase inhibitors that would offer small molecule drugs able to penetrate the BBB. Zotiraciclib is an inhibitor with effects against CDKs, both cell cycle and transcriptional kinases  and was Three-dimensional DNA structures called G-quadruplexes can form in guanine rich regions and do so also in the MYC promoter region. They are two or more secondary structures between tetrads of guanine molecules bound by hydrogen bonds . In the A new strategy deployed for targeting proteins are Proteolysis Targeted Chimeras (PROTACs). PROTACs are bifunctional three-parted drugs with one of the units binding to the protein of interest and one binding to the VHL domain of ubiquitin ligase protein E3. These two units are tethered by a linker to put the E3 ligase in close proximity to the targeted protein for ubiquitylation and subsequent proteasomal degradation . The PROin vivo opening a new therapeutic avenue for MYCN-amplified tumors. To our knowledge, indirect targeting of MYCN via RNA pol I inhibition has not been evaluated, but given its promising efficacy in NB  regulates MYCN stability through AKT and GSK3β in cerebellar neuron precursors , 144, whe et al.  showed ae et al.  demonstrin vitro and in vivo , which regulates cell growth and protein synthesis  levels in embryonic stem cells . In MYCNOCT4 has previously been shown to increase metastasis and malignancy in MB cell lines  and maliOCT4 has an important regulatory role in MYCN-amplified tumors Figure 3via MAPKAP2 that can promote MYC expression (At another dimension which might be of importance for treatment resistance in MYCN-driven cancer, involves OCT4 phosphorylation at S111 pression Figure 3pression  in recurMYC family members are found overexpressed in more than half of all cancers highlighting its role as one of the most important oncogenes. MYC proteins are involved in brain tumor initiation, maintenance and progression in both children and adults. MYCN has an important role also in normal brain development. It is known that misregulation of its expression occurs during early development in childhood neoplasms and that MYCN is likely activated during progression in adult brain tumors. While several ways of targeting MYCN is approaching and show promise, there are still many obstacles regarding delivery of direct and indirect ways to target this transcription factor. Better ways and tools to deliver MYCN-targeting drugs that penetrates the BBB is needed using e.g. chemical modifications of substances, nano-particles as drug carriers, or ultrasound technology for temporal opening of the BBB to mediate efficiently high concentrations of the MYCN drug at the tumor site.While many drugs target cMYC it is important to investigate if they are also relevant for MYCN-driven tumors or if they can be modified to target MYCN specifically to avoid unnecessary side effects. Therefore, it is of utter importance that published data on cMYC targeting also get tested in relevant MYCN-driven cancer cell and mouse models. Appropriate animal brain tumor models should not only be used to test and determine efficacy of novel drugs but will also be valuable in observing tolerability and evident toxicities of the tested compound in the preclinical evaluation. These animal models are useful tools for early detection of side effects from drugs on the normal growth of animals and on their proper brain development or consideration of future use in infant and pediatric brain tumor patients.In vivo testing of MYCN drugs for brain tumors should include irradiation and chemotherapy similar to what is used in the clinic to get solid data with a better chance to succeed in affected patients. By simply getting a drug into clinical trials it could benefit specific patients. We stay optimistic and believe that any of these measures will help providing better responses and hopefully even a cure for these devastating malignancies.As many before have suggested, combination treatments are most likely the best way to circumvent acquired drug resistance. Understanding the mechanisms behind both the drug effect and future resistance will help deciding efficient drug combinations. On this topic, one should also consider that we could shorten the bench to bedside time frame by including relevant standard treatments in preclinical testing of potential MYCN drugs. AB and FS wrote the majority of the review with extensive contributions from MC and SH. AB, SH, and FS made the figures with input from MC. MC made the table. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


To critically review the evidence in favor or against the use of house dust mite (HDM) allergen avoidance measures in patients with asthma.Systematic reviews and meta-analyses suggested no positive effect of mite allergen avoidance strategies on asthma outcomes, resulting in a lack of consensus regarding the utility of these measures. However, such analyses have a number limitations and might not be the most adequate tool to evaluate current evidence and to derive clinical recommendations regarding mite allergen avoidance in asthmatic patients. We should not disproportionately rely on the results of meta-analyses and systematic reviews to inform clinical practice and asthma guidelines in this area. Recent high-quality evidence from randomized controlled trial in children confirmed that mite allergen–impermeable bed encasings reduce emergency hospital attendance with acute severe asthma exacerbations.Until better evidence is available, we suggest that physicians should adopt a pragmatic approach to mite allergen avoidance and advise sensitized patients to implement a multifaceted set of measures to achieve as great a reduction in exposure as possible. Potential predictors of positive response  can pragmatically be evaluated using the size of skin test wheal or the titer of allergen-specific IgE. Finally, the intervention should be started as early as possible. Sensitization to house dust mite (HDM) is one of the most common causes of respiratory allergy in the world  and has We have recently reviewed this topic, outlining the potential reasons for such discrepancies . In thisThe relationship between exposure to dust mites and the development of specific sensitization and asthma is complex, with previous studies reporting inconsistent findings (reviewed in detail in ). Two diThere are many possible reasons for such divergent findings. First, available studies are difficult to compare due to major differences in study design, outcome measures, and methods of assessing exposure. Second, differences in geographic location and patterns of HDM allergen exposure and relevant co-exposures could have affected reported relationships. Furthermore, genetic background of the study populations impacting upon susceptibility to HDM allergen exposure may also differ between studies, potentially contributing to poor repeatability of results. Finally, from current evidence, it is unclear whether the time in life when individuals are exposed to high HDM levels may affect the risk of future asthma and, consequently, at what age allergen exposure should be preferentially assessed.filaggrin loss-of-function mutations, as it was shown for environmental exposure and sensitization to peanut allergen [FLG mutations had a much higher risk of being sensitized to HDM by 1 year of age  [The route of exposure to HDM allergens is considered to be primarily inhaled. However, especially in children, other routes might have a role. The oral route could be relevant for young children who frequently put hands and toys to the mouth and may ingest more than 100 mg/day of dust , 23. Senallergen . Similar5–38.58) ••.Another issue complicating the interpretation of current data on the relationship between HDM exposure and asthma risk is the absence of a reliable indicator of personal allergens exposure. In most studies, the personal exposure is assumed to equate to the concentration of allergen measured in dust samples collected by vacuuming a single square meter of settled dust on carpet or patient’s mattress. This assumption is questionable, particularly in light of evidence showing that HDM allergen levels may vary considerably within the same house and within the same sampling site  . TherefoThe evidence that high exposure to mite allergens adversely impact asthma severity in at least some mite-allergic asthmatics is much more consistent , 28–30. Dust mite allergens can be detected in most dust reservoirs, including beds, carpets, sofas, drapes, soft toys, and clothing . The maiA myriad of dust mite avoidance measures have been proposed, including mattress and pillow encasings, high-efficiency particulate air filtration (HEPA) vacuum cleaners, air purification, acaricides, humidity control, and physical removal of mite reservoirs ••. The mIn general, feather pillows are preferable to those made of synthetic materials (likely because the covers of feather pillows are woven much tightly compared to the synthetic ones) . All bedThe use of acaricides has been investigated more than 3 decades ago, but it only led to a modest decrease in mite allergen concentration when applied on carpets . Air filReducing humidity can decrease dust mite growth, but a target of relative humidity consistently well below 50% should be pursued for this intervention to be effective . PortablThe identification of sources of mite exposure is important to design effective avoidance strategies. Most mite avoidance strategies were developed under the assumption that HDM exposure among individual patients mainly occurs during time spent in bed, on the floor, or on upholstered furniture. However, a study by Tovey et al. challenged this belief, showing that most of individual mite allergen exposure in group of adults living in an urban environment in Australia occurred while commuting on public transport . It is vSeveral systematic reviews and meta-analyses concluded that the body of available evidence failed to demonstrate the effectiveness of mite allergen avoidance to improve asthma outcomes –57. ThesAn important question for practicing physicians and the members of guideline committees is whether meta-analysis is the most appropriate tool to evaluate evidence about the efficacy of dust mite allergen avoidance. There is a number of potential problems and issues with published systematic reviews and meta-analyses regarding HDM avoidance in asthmatic patients, which have been highlighted in a thoughtful and insightful article by Tom Platts-Mills . LimitatGiven these and other issues , it is crucially important to recognize the many limitations of meta-analyses and move away from over-reliance on meta-analyses and systematic reviews to inform clinical practice in this area of research and practice.Given the potential problems with meta-analyses, it is worth discussing in more detail several randomized double-blind, placebo-controlled studies which tested interventions aimed at reducing mite allergen exposure. The largest trial to date which assessed the effectiveness of bed covers as a single intervention recruited more than 1000 adults with asthma (two thirds of whom were mite sensitized) found no benefits in either primary or secondary outcome measures  . SimilarThe choice of asthma domain used as a primary outcome measure is also important. This has been highlighted in studies of biologicals in asthma; for example, mepolizumab had no effect on late-phase allergic reaction (and was deemed a failure) but was subsequently shown to substantially reduce severe exacerbations. Similarly, omalizumab has much bigger effect on asthma exacerbation rate than on symptom control or lung function.n = 146) or placebo covers (n = 138). There was a significant reduction of severe asthma exacerbation during the 12-month follow-up in the active group, with 29% of children in the intervention group having an hospital visit for asthma compared with 42% of the control group. The intervention did not influence the use of oral corticosteroids [p = 0.006), those not exposed to tobacco smoking (p = 0.02), and children who had more severe asthma (p = 0.03) and were mono-sensitized to dust mite (p = 0.04) [A very important recent RCT in children  tested the hypothesis that reduction in mite allergen exposure may reduce the risk of severe asthma exacerbations. The study enrolled 284 mite sensitized asthmatic children after being admitted to hospital with severe asthma exacerbation and randomized them to receive mite-impermeable bedding covers (steroids ••. In a  = 0.04) ••.An American study on asthmatic children evaluated the efficacy of a combining different environmental control strategies tailored to the child’s allergen sensitization and exposure status . The intOverall, the available evidence suggests that environmental control measures have been effective when they were tailored to the patient’s characteristics and home exposures and were effective in some patients, especially in children.Until better evidence is available, we suggest that practicing physicians should adopt a pragmatic approach to mite allergen avoidance and advise sensitized patients to implement a multifaceted set of measures and attempt to achieve as great a reduction in exposure as possible. If possible, the intervention should be individualized, and potential predictors of positive response  can pragmatically be evaluated using the size of skin test wheal or the titer of allergen-specific IgE. Finally, we advise that the intervention should be started as early as possible.


Promyelocytic leukemia (PML) nuclear bodies (NBs) are highly dynamic subnuclear structures. Their name giving major component, PML protein, is essential for their formation. PML is present in many different isoforms due to differential splicing, which seem to contribute differently to PML NBs function. Sp100 and DAXX are also permanently residing in these structures. PML NBs disassemble in mitosis to form large cytoplasmic aggregates and reassemble after completion of cell division. Posttranslational modifications such as SUMOylation play important roles for protein association with PML NBs. In addition to the factors permanently associated with PML NBs, a large number of proteins may transiently reside in PML NBs dependent on cell stage, type, and condition. PML NBs have been indirectly implicated in a large number of cellular processes including apoptosis, transcriptional regulation, DNA repair and replication. They are considered hot spots for posttranslational modifications and may serve as readily accessible protein depots. However, a precise function has been difficult to assign. Many DNA viruses target PML NBs after entry often resulting in reorganization of these subnuclear structures. Antiviral activity has been assigned to PML NBs partially based on the observation that PML protein is an interferon stimulated gene. In contrast, human papillomavirus (HPV) infection requires the presence of PML protein suggesting that PML NBs may be essential to establish infection. This review will summarize and discuss recent advances in our understanding of the role of PML NBs and individual protein components in the establishment of HPV infection. In this review, we are discussing the role promyelocytic leukemia (PML) nuclear bodies (NBs) play during infection with human papillomavirus (HPV). We will compare with how other viruses interact with PML NBs and the outcome for establishment of infection. The function of PML NBs has been difficult to pinpoint due to their association with many cellular processes. With their insoluble nature, PML NBs cannot be pulled down and studying these structures has been challenging, also contributing to their poor understanding. New microscopy techniques, particularly high-resolution microscopy and three-dimensional reconstruction of images, have greatly advanced our way of studying PML NBs in recent years, and thus have led to better understanding of their role in the context of viral infection.PML NBs, also known as nuclear domain 10 or promyelocytic oncogenic domains, are punctate ring-shaped dynamic structures present in the nucleus of most cell types. They have been associated with numerous cellular processes, such as cell cycle, apoptosis, stress, transcriptional regulation, genome stability, tumor suppression, and innate and intrinsic immune responses   . Although a significant decrease in viral transcripts in HaCaT cells knocked down for PML protein was observed, no differences in PML knocked down HeLa cells was apparent. Additionally, the number of pseudogenomes retained in the nucleus of HaCaT cells was greatly decreased in the absence of PML protein after successful nuclear delivery, whereas no difference was observed in HeLa cells in the presence or absence of PML protein. Loss of viral genomes in PML-deficient HaCaT cells was rescued by inhibiting the Jak/Stat signaling pathway, suggesting that immune signaling may be involved in the absence of PML protein. However, viral transcription was not restored. Taken together, the results suggested that PML protein may provide a protective environment for the viral genome against innate immune recognition and subsequent degradation. However, this is most likely not necessary in HeLa cells, which are already transformed with HPV 18 and therefore lack IFN response. Furthermore, it is tempting to assume that this protection of the viral genome by PML protein then results in efficient viral transcription and establishment of infection.PML NBs are subject to modifications during cell cycle progression (Everett et al., Using our differential staining method and high-resolution imaging, we recently showed that PML protein is recruited to viral genomes and assemble around them, rather than viral genomes targeting preformed PML NBs (Guion et al., To address this, we extended our studies to the recruitment of Sp100 to PML NBs in HPV infection. Sp100 has been observed to restrict HPV transcription and replication (Stepp et al., In our recent findings, we observed a delay in Sp100 recruitment compared to PML protein (Guion et al., HPV L2 protein is most likely the factor interacting and recruiting PML NB proteins. Although the mechanism is still unknown, it is thought to occur through SUMO interactions. Indeed, one SUMO conjugation motif, one highly conserved SIM and two additional putative SIMs have been identified in the L2 protein sequence (Marusic et al., Our recent findings suggest that L2 protein is also found at PML NBs but remains with the viral genome after loss of the transport vesicle in late interphase (Guion et al., Cells have evolved numerous processes to detect invading pathogens and render their cytoplasm inhospitable. The journey of DNA viruses is particularly treacherous, as cells can detect foreign DNA in the cytoplasm and nucleus and induce an antiviral response (Chan and Gack, MS and LG contributed to the writing of this review.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


While classical views of cerebellar learning have suggested that this structure predominantly operates according to an error-based supervised learning rule to refine movements, emerging evidence suggests that the cerebellum may also harness a wider range of learning rules to contribute to a variety of behaviors, including cognitive processes. Together, such evidence points to a broad role for cerebellar circuits in generating and testing predictions about movement, reward, and other non-motor operations. However, this expanded view of cerebellar processing also raises many new questions about how such apparent diversity of function arises from a structure with striking homogeneity. Hence, this review will highlight both current evidence for predictive cerebellar circuit function that extends beyond the classical view of error-driven supervised learning, as well as open questions that must be addressed to unify our understanding cerebellar circuit function. More than simply a neuronal learning machine, the brain is a prediction machine. Across sensory and motor systems, growing evidence suggests that a key operating principle of the brain is to establish internally generated predictions that can be compared against feedback from the external world in order to guide anticipatory actions and perceptions .The cerebellum has long been thought to operate predictively to support motor control and motor learning . As origTo refine movements based on the predicted the sensory consequences of action, the cerebellum must solve a credit assignment problem. Specifically, it must attribute deviations between actual and expected sensorimotor feedback to features of movement that occurred in the recent past. Classical models of cerebellar function argue that this problem is solved through a supervised learning rule instructed by inputs to the cerebellar cortex called climbing fibers CFs, . SuperviThis supervised learning rule works well to describe cerebellar activity in the CF and MF pathways during many behaviors, and provides a compelling model to explain how the cerebellum can modify certain movements. However, such supervised learning also requires that CFs have access to a complete menu of erroneous actions in order to provide accurate error-based feedback. This may be practical only for a limited set of behaviors, and particularly for those where the environment can directly indicate what the correct action should have been. In other words, this supervised learning rule is ideal when there is a yoked relationship between stimulus and action, as is common for many well-studied cerebellar-dependent behaviors. Eyelid conditioning provides an illustrative example of a cerebellar-dependent learning task that meets this criterion. In this behavior, animals learn to associate a neutral sensory stimulus with a delayed corneal airpuff that produces a reflexive eyelid closure. By responding via a hardwired neural pathway from the sensory periphery to the same corneal airpuff that produces a reflexive blink, CFs can accurately instruct a predictive eyelid closure according to the principles of supervised learning .In more complex motor behaviors without a fixed stimulus-action relationship, as well as many non-motor behaviors, it has been challenging to understand how such a supervised learning rule could provide an effective means for learning. In particular, in cases where the sensory information necessary for learning has no direct relationship to the movement that requires modification, or when the necessary sensory information is only applicable under a specific behavioral context, it is unclear whether or how CFs could generate such a supervised instructional signal. Indeed, there have been indications from behaviors that meet these criteria that cerebellar supervised learning models are not sufficient to describe CF activity. For example, during arbitrary visuomotor reaching tasks, CF-driven Cspks in Purkinje cells have been shown to reflect predictive signals that are not consistent with motor errors . InsteadIn a landmark study, Ohmae and Medina provided a new blueprint for how cerebellar circuits may operate to enable learning beyond a supervised context . By recoAnother key feature of TD learning models is that teaching signals are modulated by experience to represent higher-order reinforcing stimuli. Again, CF activity met this criterion, as Cspks emerged in response to the conditioned stimulus  after learning  See als. No suchThe neural seat of reward-guided reinforcement learning has historically been considered to be the striatum, where projections from VTA dopamine neurons largely obey the principles of TD models to instruct synaptic plasticity and learning about reward-predictive events . Recent It initially appears paradoxical that CF learning signals should occur in response to movements that result in reward, and thus do not immediately require modification. However, it is important to note that the reward-predictive Cspk responses associated with movement in these studies occurred in the learned condition, when the expectation that a specific movement or event would result in reward had already been established. At this timepoint, reinforcement learning principles suggest that Cspks should be used to drive second order conditioning . In otheSuch a mechanism could enable the association of multiple actions in order to establish a fully coordinated movement. To date, cerebellar-dependent sequence learning has been demonstrated only when movement feedback signals are reinforced by exogenously stimulated CF activity . These dInterestingly, while the Cspk signals reported in both Heffley et al. and Kostadinov et al. are consistent with reinforcement learning, they contrast in key ways with the Cspk patterns described by Ohmae and Medina. In particular, neither Heffley et al. nor Kostadinov et al. observed a decrease in Cspk activity when expected reward was not delivered. Instead, both studies reported elevated Cspk activity in response to defied expectations. Such responses are consistent with unsigned prediction errors, but not with the types of signed prediction errors typically associated with TD learning . The decHow might CF reinforcement signals be generated? The axons that form CFs originate from neurons in the inferior olive (IO). In many cerebellar-dependent behaviors, input to the IO that drives CFs and learning comes directly from the sensory periphery. For example, in eyelid conditioning, the corneal airpuff used as a US is transmitted to the IO via the trigeminal ganglion , reliablOne such key source of input to the IO is the mesodiencephalic junction (MDJ) . This reThe MDJ also integrates descending input from sources that include cortical pyramidal tract neurons . Such inin vivo. Thus, a key step in understanding how CFs can produce complex teaching signals such as those necessary for reinforcement learning will be to establish a more detailed map of input to the IO, and to measure the behavioral contexts under which specific input pathways recruit CF activity.The IO also receives inhibitory input, and contains some local interneurons, raising the possibility that local computations may also enrich the repertoire of CF responses . For exaTo mediate cerebellar learning, the teaching signals carried by CFs are thought to instruct heterosynaptic plasticity at excitatory synapses from granule cells onto Purkinje cells. Thus, the information carried by granule cells crucially determines what the cerebellum can learn.Classical models of the granule cell layer suggest that it serves a key role in pattern separation by expanding, sparsifying and decorrelating cerebellar input in order to maximize the number of unique representations that can be learned by Purkinje cells . Indeed,In contrast with classic models, recent work has challenged the idea that granule cells generate sparse representations, and shown that they can instead exhibit dense and redundant responses during several behaviors . Such reApart from how the granule cell layer processes incoming input, recent work has also extended our view of what the granule cells can represent. Previous work across many cerebellar-dependent learning paradigms had revealed considerable evidence that the granule cells encode the predictive context necessary for motor learning . For exain vivo recordings from rodents have revealed that granule cells can be narrowly tuned to movement features such as whisker position  can establish complex kinematic predictions about movement across diverse behaviors . Such daWhile CF input to Purkinje cells is typically considered to be the teaching signal necessary to update cerebellar forward models, there is also evidence that the granule cell pathway may carry feedback error signals . Such erIn cases where CF activity is strongly linked to learning, the primary model suggests that these signals serve to instruct long-term synaptic depression (LTD) of granule cell synapses onto Purkinje cells . This meIndeed, while current evidence suggests a role for plasticity of various types and at multiple sites in the cerebellar circuit , there rAt the level of the CbN, direct evidence to illustrate predictive cerebellar output has been somewhat limited. Clear examples had previously existed only for a small number motor behaviors with similar learning requirements. For example, during eyelid conditioning, CbN neurons become active to the conditioned stimulus to enable a predictive eyelid closure by activating downstream motor neurons . Until rBy recording from the CbN of awake behaving primates, Brooks and colleagues showed that these neurons can dynamically track the difference between expected motor output and sensory feedback, consistent with the computation of sensory prediction error during voluntary head movements . In partTo begin addressing the casual relationship between CbN activity and behavior, a recent study has used closed-loop optogenetic manipulations to alter the firing of CbN neurons during movement . By bothRecently, studies focused on neocortical areas have suggested a cerebellar influence on downstream targets that is at least reminiscent of forward model predictions . In addiCbN output to ALM may also reflect the expected outcome of motor plans. Similar to the results of Gao et al., Chabrol et al. found that cerebellar CbN output was necessary for ramping in ALM . HoweverTogether, these ALM results are consistent with studies in non-human primates showing that neurons in the lateral CbN can exhibit predictive ramping responses during a delay period prior to movement . While sOverall, these studies may point toward a forward-model explanation for how cerebellar output affects neocortical areas, as in each case the cerebellum appears to signal temporally-specific predictions about behavioral outcomes related to the function of these areas. However, much work remains to rigorously test this hypothesis, and will require a more complete understanding of the cerebellar computations involved in neocortical processing, as well as a clear description of how signals from discrete cerebellar output pathways act to sculpt neocortical activity.Because the neocortex also feeds back to the same cortical targeting regions of cerebellum via the pons in a closed-loop manner , it is lOver the last several decades, there has been a growing appreciation that the cerebellum contributes to a wide range of non-motor processes , includiIndeed, motivated by such findings, Strick and colleagues have used transynaptic rabies tracing methods to elucidate several discrete pathways from the cerebellum to brain regions other than the motor cortex , includiFollowing similar guidance, another recent study has identified a circuit pathway that provides a link between cerebellar output and vocal learning . PreviouFinally, another vital insight from human studies has come from the many observations that neurodevelopmental disorders, and particularly autism spectrum disorders (ASDs), strongly correlate with cerebellar damage during birth and mutations in cerebellar genes . These iTogether, such studies have highlighted the importance of using information gleaned from human studies of cerebellar activity and disease states to guide circuit based interrogations in animal models. However, as new work continues to emerge suggesting cerebellar contributions to a wide range of motor and non-motor behaviors, a key challenge will be to identify what common principles may link the role of cerebellar predictions across behaviors, or what properties of cerebellar computation may be unique to individual behaviors.A meaningful understanding of how cerebellar circuits operate predictively must span multiple levels of inquiry, merging mechanistic insights at the cellular and synaptic level with functional explanations of how cerebellar computation modifies behavior. Thus, in considering a way forward, it can be useful to organize the question of what experiments are necessary according to a conceptual framework. As is frequently remembered , Marr (1At the level of computation, it would initially seem that the cerebellum is tasked with solving multiple problems, as it clearly contributes to both motor control and diverse cognitive processes. However, this information alone does not resolve the question of what specific problem the cerebellum is tasked with, as its discrete contribution to such diverse behaviors remains opaque. Indeed, the question of whether the cerebellum performs a so-called ‘uniform transform’  or exhibAt the algorithmic level, current evidence suggests at least two different learning rules that the cerebellum can harness to predictively modify its inputs. If the cerebellum can utilize both supervised  and reinIf the cerebellum does exhibit multiple functionality, the learning rules used may also be area-specific, as it is clear that the cerebellum is functionally compartmentalized . Again, Finally, at the implementation level, the crystalline cellular architecture of the cerebellum has long suggested uniformity in the basic building blocks for executing cerebellar computation. However, there is also ample evidence that, despite this gross uniformity, there are many regional specializations that shape neuronal excitability, relative density of distinct cell types, molecular marker expression, and other circuit properties . MoreoveTo understand whether and how the implementation of cerebellar learning can differ, it will be important to move beyond single cell or single cell-type measurements. In particular, since learning is likely to involve multiple mechanisms across many sites, simultaneous, circuit-wide measurements are necessary, ideally across different behaviors and species to identify common principles. To achieve this, modern population level recordings based on calcium imaging or high-density electrode arrays will be indispensable in order to generate a holistic picture of how cerebellar processing is implemented.Together, such measurements targeted across multiple levels of analysis will be essential to achieving a comprehensive, circuit-based understanding of how the cerebellum functions as a neuronal prediction machine. And, while the current paradigm shift beyond motor errors has added new complexity to our understanding of cerebellar circuit function, these experiments are sure to ultimately be rewarding.