This review aims to summarize interventions used in the perioperative period to reduce the development of new persistent postoperative opioid use in opioid-naïve patients.The development of new persistent opioid use after surgery has recently been identified as a common postoperative complication. The existing literature suggests that interventions across the continuum of care have been shown to decrease the incidence of new persistent postoperative opioid use. Specific preoperative, intraoperative, and postoperative interventions will be reviewed, as well as the use of clinical pathways and protocols that span throughout the perioperative period. Common to many of these interventions include the use of multimodal analgesia throughout the perioperative period and an emphasis on a patient-centered, evidence-based approach to the perioperative pain management plan.While the incidence of new persistent postoperative opioid use appears to be high, the literature suggests that there are both small- and large-scale interventions that can be used to reduce this. Technological advances including prescription monitoring systems and mobile applications have enabled studies to monitor opioid consumption after discharge. Interventions that occur preoperatively, such as patient education and expectation setting regarding postoperative pain management, and interventions that occur postoperatively, such as the implementation of procedure-specific, evidence-based prescribing guidelines and protocols, have been shown to reduce post-discharge opioid consumption. The use of multimodal analgesia and opioid-sparing adjuncts throughout the perioperative period is central to many of these interventions and has essentially become standard of care for management of perioperative pain. It is well known that the USA is facing an ongoing opioid crisis, with the number of opioid overdoses and deaths on the rise. Between 1999 and 2008 opioid prescribing in the USA quadrupled, with a parallel increase in reported overdoses [Surgical patients are particularly vulnerable during the perioperative period, as the majority of them are exposed to opioids at some point during this time. Up to 14.7% of patients who are opioid-naïve may develop persistent postoperative opioid use , and stuThe incidence of new persistent opioid use after surgery is multifactorial, related to patient-specific risk factors, the type of surgery, and prescribing behaviors during the perioperative period. While there have been various interventions designed to decrease opioid use in the immediate perioperative period, lack of long-term longitudinal follow-up precludes an accurate assessment of the impact on new postoperative opioid use. This article will discuss risk factors associated with persistent opioid use after surgery and provide an up-to-date review of interventions designed to prevent new persistent opioid use after surgery. Interventions under discussion will include perioperative protocols/clinical pathways and programs, as well as preoperative-, intraoperative-, and postoperative-specific interventions.Risk factors associated with the development of persistent postoperative opioid use in previously opioid-naïve patients include patient-related risk factors, surgical factors, and the perioperative pain management plan. Multiple patient-specific variables have been identified as potentially contributing to new persistent opioid use, including substance use disorders, mood disorders, and preexisting chronic pain , 9••. SpThe implementation of multidisciplinary perioperative protocols which focus on the use of opioid-sparing multimodal analgesia modalities throughout the continuum of care, like Enhanced Recovery after Surgery (ERAS) protocols, have consistently shown to be associated with decreased perioperative opioid consumption. While the majority of studies examining the effects of ERAS protocols on perioperative opioid use terminate at patient discharge, tracking post-discharge opioid use has enabled more recent studies to examine the impact of ERAS protocols on both discharge and post-discharge opioid prescriptions. Liu et al. (2019) implemented an ERAS protocol targeting two patient populations  with specific multimodal non-opioid adjuncts and followed patients for up to 1 year after surgery. Using pharmacy dispensing records it was reported that implementation of the ERAS protocol was associated with more than a 20% reduction in opioid refills 3 months to 1 year after surgery . Razi etTechnological advances have enabled the incorporation of novel mobile applications into ERAS protocols, which can aid in tracking postoperative opioid use. Pickens et al. (2019) found that the implementation of a mobile application for real-time collection of patient-reported outcomes for 30 days after hepatopancreatobiliary surgery within an ERAS pathway resulted in decreased opioid consumption and pain scores, increased compliance with ambulation and breathing exercises, and prevention of emergency room visits . Future Another example of a multidisciplinary, integrative approach to the prevention of new persistent postoperative opioid use is Toronto General Hospital’s Transitional Pain Service, which is designed to identify patients at risk for chronic postsurgical pain and opioid use and offer coordinated and comprehensive care throughout the perioperative period. Patients are seen preoperatively, postoperatively in the hospital, and after discharge in an outpatient setting for up to 6 months after surgery . Clarke The preoperative period is a critical stage where patients with risk factors for the development of new persistent opioid use can be identified early on, which can prompt the early involvement of programs like Toronto General Hospital’s Transitional Pain Service. In these patients, it is important to obtain baseline pain levels prior to surgery, as this information can help to prevent overzealous treatment of postoperative pain . StudiesOver the past 20 years, there has been a paradigm shift in the management of perioperative pain, with an evolving focus on the use of multimodal analgesia in the immediate perioperative period to reduce unnecessary opioid exposure. Multimodal analgesia, referred to above, is defined as two or more interventions with varying mechanisms of action for postoperative pain relief . It has Given the lack of large-scale data on post-discharge pain trajectories and opioid usage, lack of guidance regarding optimal postoperative pain management, and the resulting widespread variability in prescribing practices, multiple studies have focused on postoperative-specific interventions to decrease opioid consumption after discharge . Many suProvider education and implementing procedure-specific prescribing guidelines for discharge have consistently been shown to reduce new persistent opioid use , 31–34. Lastly, a review of a novel electronic health modality aimed at optimizing pain management while decreasing unnecessary opioid consumption was recently published, in which the authors designed and implemented a mobile application guiding patients in pain management and opiate use in the first 2 weeks after discharge from a total knee replacement. They reported that use of the application resulted in decreased opioid consumption, and more frequent use was associated with a more pronounced result ••. WhileWith growing evidence that new persistent opioid use after major and minor surgery is relatively common, there has been an increased interest in longitudinal follow-up of postoperative opioid use. Efforts are being made across the continuum of care to limit unnecessary exposure to opioids. Current literature suggests that interventions can be performed throughout the perioperative period to successfully decrease the risk of patients developing new persistent postoperative opioid use. Early identification of patients at risk can help to tailor interventions within the context of a multidisciplinary perioperative pain management plan. The use of multimodal anesthesia and analgesia, enhanced recovery pathways, and additional opioid-sparing techniques have become the standard of care in the management of perioperative pain. While many studies examining single interventions in isolation have shown to consistently decrease opioid requirements in the immediate perioperative period, few studies report the impact on opioid consumption after discharge and the same is true for many of the ERAS studies. Future studies are needed to determine if the observed decrease in in-hospital opioid use translates into decreased post-discharge opioid use and the development of new persistent use. Fortunately, technological advances including prescription monitoring and centralized electronic medical record systems are making post-discharge tracking more feasible, which will enable future studies the ability to follow patients in the longer term. Additionally, the use of mobile electronic applications as a way to decrease post-discharge opioid consumption appears to be a promising new development, enabling closer follow-up, monitoring, and patient-centered prescription guidance.


Thought to be directly and uniquely dependent from genotypes, the ontogeny of individual phenotypes is much more complicated. Individual genetics, environmental exposures, and their interaction are the three main determinants of individual’s phenotype. This picture has been further complicated a decade ago when the Lamarckian theory of acquired inheritance has been rekindled with the discovery of epigenetic inheritance, according to which acquired phenotypes can be transmitted through fertilization and affect phenotypes across generations. The results of Genome-Wide Association Studies have also highlighted a big degree of missing heritability in genetics and have provided hints that not only acquired phenotypes, but also individual’s genotypes affect phenotypes intergenerationally through indirect genetic effects. Here, we review available examples of indirect genetic effects in mammals, what is known of the underlying molecular mechanisms and their potential impact for our understanding of missing heritability, phenotypic variation. and individual disease risk. Years of genetics have attributed uniquely to genes (and genotypes) the ability to generate and transfer phenotypes across generations Gayon . In 1893Studies from the last decades have broken this dogma and shown that continuous phenotypic traits  are plastic, respond to environmental challenges during the lifetime and these responses can be inherited across two or more generations, through epigenetic mechanisms (Sabour and Scholer Genome-Wide Association Studies (GWAS) aimed to identify the genetic basis of human diseases and have provided a genetic framework for our understanding of disease biology, heritability and individual’s susceptibility. While GWAS have identified more than 100,000 strong trait-variant associations , several additional phenomena have been proposed as potential underlying causes of the missing heritability including intrinsic GWAS experimental limitations, heritability overestimations, variants with small effect-size, epigenetic mechanisms, gene/environment interaction and acquired inheritance, and many others   system for example lead to a characteristic tail-painting phenotype, which is maintained in wild-type offspring and persists across multiple generations  can influence the phenotype of wild-type offspring  and genes with previously unknown epigenetic function , andthey generally persist across several generations.All together, these findings provide evidence that:Interestingly enough, indirect genetic effects have been also identified in two large humans studies. Kong et al. involved more than 20,000 probands and their genotyped parents to look at the effect of transmitted and non-transmitted parental genetic information on offspring educational attainment  influence the living environment and thereby shape the phenotype of non-carrier individuals (offspring or siblings) sharing the same environment. This is a likely explanation for human studies, where—for the majority of them—it is impossible to avoid parent/offspring environmental sharing, and very hard to dissect molecular mechanisms. Conversely, similar studies in experimental models offer the opportunity to control for developmental and post-natal environment and dissect (or try to) the underlying molecular mechanisms.Despite a growing body of evidence in support of indirect genetic effects, the findings remain mostly descriptive and the underlying molecular mechanisms are far from being completely understood. Kong et al. renamed the indirect genetic effect identified in their human study as “paramutations-like phenomena. A paramutation is one example of genetically controlled heritable epigenetic variation which defies Mendel’s first law of inheritance, according to which alleles are transmitted unchanged. The first example of paramutation was reported independently by the studies of Brink  in a manner which is maintained through multiple generations. A universal hallmark of paramutation is that paramutant alleles become paramutagenic following exposure to another paramutagenic allele in trans , which—by targeting the wild-type Kit mRNA—are sufficient to recapitulate the offspring phenotype when microinjected into wild-type fertilized oocytes  Regulatory sequences can function ectopically ; (2) Paramutation-like phenotypes are heritable and stable through generations independently from the presence of the paramutagenic allele; and (3) Paramutation-like phenomena can be artificially induced supporting its sequence-driven nature.Although paramutations—defined as RNA-based trans-homologous epigenetic modulation of gene expression—are unlikely to globally explain indirect genetic effects in mammals, the concept of trans-acting mechanisms which, triggered by mutated alleles, can induce trans-acting stable and heritable epigenetic reprogramming at other alleles of the same or—most likely—different loci and multigenerational phenotype transfer, is indeed interesting and worth deeper investigation.The examples of indirect genetic effects presented in this review already constitute a compelling catalog, as they encompass various complex phenotypes and diverse genetic triggers. The next and critical questions to address will be how common these indirect genetic effects are in mammals, which complex phenotypes they can trigger/stabilize and—most importantly—whether they can reveal at least part of the missing heritability highlighted by genome-wide association studies.The main goal of this review was to convey the message that indirect genetic effects—broadly defined as genetically determined , genotype-independent (as their manifestation is independent from the carried genotype) control of phenotypic variation across generations—may be more common and relevant than actually thought for the pathophysiology and the heritability of complex traits in mammals. Further and deeper study of indirect genetic effects might therefore constitute a strategy to identify at least part of the missing heritability associated with GWAS signals and might help shedding light on complex disease biology and individual disease susceptibility in humans.A first and necessary step towards unraveling the real potential of indirect genetic effects for human health is to understand how common they really are in mammals, and to identify associated genes and/or gene families and functions. This need calls for the importance for the scientific community to have access to unbiased, comprehensive, systemic and highly controlled datasets. One example of those datasets is the one provided by the efforts of the International Mouse Phenotyping Consortium (IMPC). The IMPC is an international establishment, which aims to generate and systemically phenotype—with tests encompassing a wide range of system areas, including neurological, behavioral, metabolism, cardiovascular, pulmonary, reproductive, sensory and musculoskeletal functions—mouse mutants for every gene in the mouse genome. A combined effort of more than 20 institutions worldwide provides access for the scientific community to comprehensive and standardized mouse phenotypic data for the purpose of identifying human-relevant disease causing genes  will add a new dimension to gene function (gene-dependent/genotype-independent), shed light on parental contribution to offspring phenotypic trajectories and hopefully boost discoveries on human genetics and the relevance of human genetic variation for individual susceptibility to complex diseases, such as diabetes, obesity and cancer.


Ultrasound can penetrate deep into tissues and interact with human tissue via thermal and mechanical mechanisms. The ability to focus an ultrasound beam and its energy onto millimeter-size targets was a significant milestone in the development of therapeutic applications of focused ultrasound. Focused ultrasound can be used as a non-invasive thermal ablation technique for tumor treatment and is being developed as an option to standard oncologic therapies. High-intensity focused ultrasound has now been used for clinical treatment of a variety of solid malignant tumors, including those in the pancreas, liver, kidney, bone, prostate, and breast, as well as uterine fibroids and soft-tissue sarcomas. Magnetic resonance imaging and Ultrasound imaging can be combined with high intensity focused ultrasound to provide real-time imaging during ablation. Magnetic resonance guided focused ultrasound represents a novel non-invasive method of treatment that may play an important role as an alternative to open neurosurgical procedures for treatment of a number of brain disorders. This paper briefly reviews the underlying principles of HIFU and presents current applications, outcomes, and complications after treatment. Recent applications of Focused ultrasound for tumor treatment, drug delivery, vessel occlusion, histotripsy, movement disorders, and vascular, oncologic, and psychiatric applications are reviewed, along with clinical challenges and potential future clinical applications of HIFU. In clinical practice, a variety of different energies have been used for thermal ablation of tissues, including radiofrequency currents, microwaves, laser, thermal conductor sources, and ultrasound. Ultrasound provides several important benefits, such as enabling deeper tissue treatment, improved focus on the target tissue through its small wavelengths, and precise control over the shape and location of energy deposition . Using uOver the past two decades, continued advances in imaging, physics, and engineering have enabled precise focusing of ultrasound on deeper targets in the body. High intensity focused ultrasound (HIFU) is one of the more active research areas among non-ionizing ablation methods; such as lasers and microwaves. HIFU treatment is usually guided, assessed, and monitored by either magnetic resonance imaging (MRI) or ultrasound imaging . RecentlThe key to HIFU treatment is that the energy delivered is sufficient to increase the tissue temperature to a cytotoxic level very quickly so that the tissue vasculature does not affect the extent of cell killing. Heat coagulation by HIFU is desired for cell reaction with chronic inflammation, and histological signs of fat necrosis in the surrounding normal fatty tissue . Large bThis review aims to provide an introduction to the physical principles of HIFU, including its heating and mechanical (cavitation) effects in the body, along with a brief overview of the current clinical therapeutic aspects of HIFU.HIFU beam can pass through overlying skin and tissues without harm, and focus on a localized area with an upper size limit of approximately 3–4 cm in diameter for tumors. The basic principles underlying the tissue damage from HIFU are tissue coagulative thermal necrosis due to the absorption of ultrasound energy during tissue transmission  and ultrasound-induced cavitation damage . The heaAnother mechanism involved in HIFU ablation is mechanical effect. This mechanical effect, including cavitation, only occurs with high intensity acoustic pulses . CavitatOverall, HIFU equipment consists of two main components. The first is a piezoelectric ultrasound transducer that is used to deliver the therapeutic ultrasound beam. The most popular type of transducer used is a concave focusing transducer with a fixed aperture and focal length a. Other The second major component of HIFU is the imaging modality used for guidance. Real-time imaging during therapeutic procedure is essential to ensure the safety and efficiency of the treatment. The imaging modalities that have been used for monitoring treatment are sonography and Magnetic Resonance Imaging (MRI). MRI with its high anatomical resolution and sensitivity for tumor detection offers accurate planning of the tissue to be targeted and treated. In addition, MR thermometry enables calculation of the thermal dose and a superimposed representation of the anatomical image of the area where the temperature reaches cytotoxic levels. It provides closed-loop control of energy deposition with a temperature accuracy of 1 °C, spatial resolution of 1 mm, and temporal resolution of 1 s during HIFU treatment . Within Compared to MRgFUS, ultrasound imaging is more convenient and mechanically compatible, and provides the same form of energy for image guidance as used for therapy. It provides the benefit of verifying the acoustic window with sonography in real time, which means that if the target region is not visualized by ultrasound imaging before and during HIFU therapy, then it is unlikely that HIFU therapy will be effective in that specific region. The ablated target region is not visualized on standard B-mode images unless the gas bubbles produced within the focal zone appear as hyperechoic spots in the image . USgFUS There are three different ways to apply HIFU to the human body based on the accessibility of the targeted organ to ultrasound. When the organ is readily accessible, such as the kidney, HIFU is applied through an acoustic window on the skin by external or extracorporeal transducers a. In othTransrectal and interstitial transducers usually operate at higher frequencies and lower power so they can be applied from smaller distances to the target area. The devices developed for transrectal use have combined therapy and imaging transducers incorporated into the head of the transducer probe with a fixed but adjustable focal point that can be mechanically moved to treat a larger tissue volume b. ProstaDepending on the geometric size and acoustic parameters of the transducers applied in a HIFU system, the beam size of a −6 dB HIFU system at its focal region is typically 1–3 mm in width and approximately 10 mm in length . HoweverOverall, the therapeutic ultrasound frequency depends on the application-specific treatment depth and the desired rate of heating required for treatment. Higher frequencies have lower penetration depths while lower frequencies have higher penetration depths. Frequencies as low as 0.5 MHz have been used for deep treatments  or high absorption situations and as high as 8 MHz for superficial treatments (including prostate applications) . FrequenMany benefits justify further exploration of HIFU for additional future clinical applications: HIFU ablation results in reduced toxicity compared with other ablation techniques; it is non-invasive and causes minimal pain; it is a low-cost procedure compared with surgery; less anesthesia involvement and suitable for patients at high surgical risk; it leaves no scars on the patient; lower infection risk; recovery is faster compared with traditional surgery techniques; any bleeding that occurs during the procedure can generally be stopped by ultrasound; it has excellent repeatability as there is no dose limit;, there is no exposure to ionizing radiation due to being guided by MRI or diagnostic ultrasound as opposed to X-ray imaging, precise energy delivery to a targeted point in soft tissue without affecting the skin integrity; system maintenance costs are low; it causes very limited side effects to normal surrounding tissues ; patientIn terms of limitations, HIFU treatment is sensitive to patient movement, and near-field heating, and the treatment time can be as long as several hours. When an extracorporeal device is used to distribute the incident energy over a large skin area, the device has a wide aperture and long focal length to decrease the acoustic intensity at the wave site to avoid skin burn. However, severe full skin burns following extracorporeal shock wave lithotripsy (ESWL) for renal calculi  or seconHIFU has been used to treat a variety of solid malignant and benign tumors. HIFU has the advantage of being completely non-invasive, extracorporeal, and non-ionizing modality compared to conventional cancer treatment methods such as chemotherapy, radiotherapy, and open surgery. It is also considered as the only non-invasive technique for both primary solid tumors and metastatic disease treatment. Non tumorous conditions such as prostate hypertrophy have also been treated using HIFU technique. Here we discuss the most frequently used clinical applications of HIFU.Hepatocellular carcinoma (HHC), is one of the most common and often one of the most difficult to treat liver cancer, especially when multicentric. This can make the outcome of surgical resection poor, with high risk of tumor recurrence . ExtracoHIFU can be an effective nonsurgical technique for breast cancer treatment particularly for high-surgical-risk patients and breast-conservation therapy. This is because of its local tumor necrosis effect, lessened requirement for anesthesia , shorterProstate cancer treatment trials using trans-rectal HIFU has shown promise over the past decade in more than 100 sites across the world . Different studies have reported significant drop in prostate-specific antigen (PSA) (to ≤0.2 ng/mL) and promising survival rate in patients ,40,41,42HIFU has been shown to be a safe technique with minimal side effects; however, some uncommonly encountered complications have been reported including urinary retention, infection, incontinence, urethral stenosis, impotence, rectal fistulas, and chronic pain , which hWhen renal tumors are small in size, non-invasive HIFU ablation therapy is an attractive alternative method compared to total or partial nephrectomy. The few clinical studies that have examined HIFU for ablation of kidney cancer tumors have reported promising outcomes of histology-proven irreversible and homogenous damage of treated areas , tumor nEsophagus cancer is often identified as a small localized intraluminal squamous-cell carcinoma. Common treatment methods involve surgery and chemotherapy with or without radiation therapy. These methods have overall poor outcomes; with 5-year survival rates of 13–18% . ClinicaPancreatic cancer is typically detected late with 5-year survival rates of <5%. While surgery is only a possible option for 20% of patients, HIFU is emerging as a potential treatment technique. HIFU has been increasingly used either alone, in combination with chemotherapy (gemcitabine), or as additional therapy after failure of chemo/radio therapy ,57. ResuReports on side effects and complications of the HIFU treatment have been variable. While some studies have reported no complications , others Glioblastoma is the most common malignant tumor of the central nervous system. It is commonly treated with surgical resection and chemo/radiation therapy. Main challenges in management of brain tumor is the diffuse spread of the tumor throughout the brain and inability of chemotherapy regimen to cross blood brain barrier (BBB) . HIFU, dReports of HIFU used to treat bone include applications for destruction of tumor microvessels and thrombosis to prevent haematogenous tumor cells dissemination , pain paCommercially used HIFU systems in the reported studies are ExAblate 2000   and ModeUterine fibroids or uterine leiomyomata are benign smooth muscle tumors of the uterus, fallopian tubes, broad ligament, or cervix, affecting about 25% of women . HIFU is3 volume, in less than 15 min has also been demonstrated on excised tumors using an inserted interstitial ultrasound ablator [Commercially available systems used in these studies are ExAblate 2000 , a Haifu JM therapeutic system , HIFUNIT 9000 , and a custom made mobile HIFU unit . HIFU treatment of large fibroids; ~4 cm in dameter, >45 cm ablator . The HIF ablator . Althoug ablator . Overall ablator .Fibroadenomata (FAD) are benign breast lesions typically removed surgically. In addition to conventional surgical removal of the lump or vacuum-assisted mammotomy, other techniques such as HIFU, cryo- or laser ablation have also been used. A comprehensive review of these techniques by Peek et al. indicated that all these ablative techniques are minimally invasive and promising for FAD treatment .The ability to focus and target the US beam through the intact skull to areas as small as a couple of millimetres has been a considerable milestone in enabling precise, local ablation of intracranial brain tissue to overcome certain brain disorders . HIFU haEssential tremor (ET) is a movement disorder affects the upper extremities and dominant arm. When severe it is often managed by surgical disruption of the ventral intermediate nucleus of the thalamus; achieved by insertion of the invasive probe and radio frequency (RF) thalamotomy at 75–80 °C or by deep stimulation of the brain that may cause infection and/or hemorrhage . Recent Parkinson disease is characterized by progressive degeneration of motor neurons. Disruption of key motor nuclei can lead to significant improvement in motor symptoms . HIFU caCentral- and peripheral-type pain syndromes are challenging conditions to treat especially when common pharmacological medications are ineffective. Destructive procedures can be used to ablate the sensory or affective components; brain and spinal cord in central- and nerves or nerve bundles in periphery-type chronic pain cases . HIFU haHIFU treatment of benign prostate conditions presents different problems compared to malignant prostate cancer, since prostate cancer is generally a multi-focal disease. Whole gland HIFU ablation has been more successful in benign tumors . ProstatThyroid nodules have been treated using a variety of different techniques, with surgery still the most common and effective approach. This involves risks and complications of hypocalcemia, transient or permanent recurrent laryngeal nerve palsy, bleeding, postoperative infections . RecentlThe main HIFU device used to deliver medication into human brain for a wide variety of brain diseases and also for scalpel-free surgery of brain tumour is the ExAblate Neuro , which consists of a spherical, phased array, multi-element (1000 transducers) helmet that is computer controlled for wave front distortion compensation . PatientDiagnostic imaging systems have been used along with HIFU devices to provide improved safety, therapy navigation, and provide assessment of vascularity or ablation quality during or after treatments. The main reported imaging methods are ultrasound guided FUS (USgFUS) ,62,104 8HIFU is emerging as a potential technique for occluding blood vessels in different diseases or conditions such as in arteriovenous malformations to control hemorrhage or in shrinking a solid tumor by blocking/interrupting its blood supply . FurtherThe mechanical disruption ability of HIFU, mediated by cavitation, makes it an attractive technique to locally open the blood brain barrier (BBB); Cavitation bubble-induced BBB disruption can be performed either by very high HIFU exposure, which may cause blood vessel rupture or occlusion , or moreIntracerebral hemorrhage is currently treated with thrombolytics and surgery. HIFU offers the capability to liquefy blood for facilitated aspiration, which can help decrease clot burden and mass effect to avoid craniotomy . Blood cAbscesses especially when caused by methicillin-resistant Staphylococcus aureus (MRSA) bacteria may be difficult to treat. A recent feasibility study applied HIFU, at two focal temperatures of 52 and 64 °C, on targeted MRSA-induced abscesses in mice. Post HIFU ablation of 64 °C, significant reduction in bacterial load and abscess external size was observed at day 4 and 10, respectively . No sideIntegrating focused ultrasound with different existing therapeutic technologies can improve clinical outcomes. Enhanced skin permeabilization using this technique may replace multiple needle use for medicines such as heparin and insulin or enable diffusion of large molecules (>500 Da) through stratum corneum ,115. FocBoth thermal and non-thermal (cavitation) effects play a very important role in all therapeutic applications of ultrasound. The side effects of these two mechanisms of action can be injurious biologically and are therefore avoided in diagnostic applications of ultrasound but can be beneficial in therapeutic applications. The ability to focus the ultrasound beam to a small area a couple of millimeters in size enhances both the thermal and non-thermal effects of ultrasound and results in ablation and necrosis of cells at the applied focal point. This makes ultrasound an excellent non-invasive therapeutic ablation technique for deep-seated targets within the body. HIFU therapy provides a less invasive approach to cancer therapy that minimizes discomfort to the patient and length of hospital stay. Initial studies have demonstrated HIFU to be generally safe and clinically effective and to have high potential clinical acceptance. However, HIFU is still in its infancy and further studies are necessary  regarding the long-term medical benefits, technical considerations, and treatment delivery before transition to more widespread use. The range of HIFU applications may expand in the future with improved imaging. MRgFUS is one of the most successful imaging guide approaches. However, there is a need for additional studies with longer-term follow-up.


We report on a multi-season study of smallholder food producers' experiences with Rwanda’s Crop Intensification Program (CIP) and related policies that aim to commercialize subsistence agriculture while implementing CSA. . We suggest that there are fundamental limits to the climate resilience afforded by CSA and development efforts rooted in Green Revolution thinking. Our findings illustrate that such efforts foreground technology and management adjustments in ways that have reduced smallholder resilience by inhibiting sovereignty over land use, decreasing livelihood flexibility, and constricting resource access. We put forth that rural development policies could better promote climate-resilient livelihoods through: 1) adaptive governance that enables smallholder land use decision-making; 2) support for smallholder food producers’ existing agro-ecological strategies of intensification; 3) participatory approaches to visualize and correct for inequalities in local processes of social-ecological resilence Such considerations are paramount for meeting the United Nations Sustainable Development Goals and building climate-resilient food systems.Under the banner of a "New Green Revolution for Africa," agricultural intensification programs aim to make smallholder agriculture more productive as well as "climate smart". As with Green Revolutions in Asia and Mexico, agricultural innovations  are promoted as essential catalysts of agriculture-led economic growth. Intensification programs are now frequently linked to Climate Smart Agriculture (CSA), which attempts to build resilience and reduce greenhouse gas emissions while increasing crop yields. This article considers  Adoption of these technologies was sparse in sub-Saharan Africa (SSA), largely due to structural adjustment and fiscal austerity measures that weakened state agricultural initiatives . Since the mid-2000s, a resurgence of agricultural intensification programs has swept across SSA . With suwho and what is resilient in Africa's Green Revolution.Central to the narratives legitimizing SSA's Green Revolution is a need to build climate resilience , with intensification pitched as essential to ensuring adequate food production despite projected climatic shocks and population increases in SSA ;. These Questions of "for whom"  resilienThe perceived vulnerability of smallholder agriculture to climate shocks has become central to the discourse validating the present Green Revolution land use policies in SSA  and CSA what and who is resilient . Smallholders in SSA pursue a range of livelihood activities along the spectrum of subsistence to commercial, often blending these strategies . Capacit2.2Many maintain that agricultural intensification is essential to economic growth and poverty reduction in SSA . In bidsIndeed, contemporary intensification programs, while often rebranded as sustainable intensification, appear to recreate many of these uneven effects on food security, poverty alleviation, nutrition, and the environment . In SSA,2.3Rwandan food producers have for generations optimized land use systems by intensively cultivating diverse crops across soil moisture regimes that are a function of space (different hill locations) and time (two rainy seasons and two dry seasons each year) . Over thThe Government of Rwanda (GOR) has for years promoted input-led agricultural intensification with aims to commercialize smallholder production systems according to the priorities of the state and international development organizations . These gimihigo), households submit written agreements that they will cultivate selected crops several months before the growing season begins. Those failing to meet contracts or found to plant non-approved crops can be publicly disgraced and penalized . An indirect result of the CIP is thus that subsistence croping strategies and key food security crops are functionally illegal in certain areas. The imposition of the CIP is, in this way, reminiscent of colonial-era polices as documented in Rwanda , and expanded agriculture extension services . Smallhon Rwanda  and in En Rwanda .Although the CIP is guided by quintessential Green Revolution goals and technologies, two features make Rwanda's efforts of agricultural modernization emblematic of SSA's new Green Revolution. First, non-state and private-sector partners are responsible for the transfer of agricultural intensification technologies  to smallholders. In much of Rwanda, 'improved seeds' of government-selected crops and chemical fertilizer are delivered on credit by the One Acre Fund as part of a "bundle of services" that also includes agricultural training. Many of the terraces and irrigation infrastructure were built through the Land Husbandry, Water Harvesting, and Hillside Irrigation (LWH) project, a joint effort of the World Bank and the Rwandan Government. Secondly, climate change is invoked by each of these actors, with claims of making agriculture "climate smart." The LWH project, a 135 million USD operation that ran from 2010 to 2018, is described as having drawn on "expertise in climate-smart agriculture since 2010." The project intended "to address the critical agenda of hillside intensification through improved land husbandry" with the goal of "increasing productivity and livelihoods and reducing climate vulnerability" . While iNationally, the CIP has been hailed as a success for increasing crop yields and decreasing rural poverty . This in turn has earned Rwanda accolades and continued donor investment in the Green Revolution policies of the CIP . Likewis33.1umudugudu  in Nyamagabe district. Located in southwest Rwanda, Nyamagabe (formerly Gikongoro) has historically been among Rwanda’s poorest regions. As elsewhere in Rwanda, a feudal system structured land use in the pre-colonial era—with Tutsi owning land and grazing cattle and Hutu practicing agriculture on rented land—and persisted through the colonial period. As much of the land was reserved for pasture, agriculture intensified and colonial land use policies sought to avoid land degradation through building terraces and erosion ditches  indicates that poverty has reduced dramatically over the past five years. Rwanda’s National Adaptation Plan of Action  categorizes Nyamagabe as a region with high occurrence of both drought and heavy rain. Smallholder agriculture is the principal livelihood for nearly all households in the region, with rain-fed production tied to two annual growing seasons . Some households diversify livelihoods with non-farm employment  and by selling commercial crops in addition to subsistence. The CIP has been active in the study communities since 2010 and has been adopted by 90 percent of households.3.2Qualitative and quantitative methods were conducted at farm-plot, intra-household, household, and institutional levels. A household survey on resource access, livelihoods, decision-making, and climate risk management was conducted by a team of five research assistants with all available households in the four communities n = 428. A parcel-level survey was conducted with the 402 households with operational holdings n = 3017 agricultural parcels, examining biophysical aspects of fields as well as inputs, crop yields, and impacts of climate shocks. Each survey was pilot tested with more than 25 respondents. Surveys were conducted by four teams of two research assistants. Research assistants were experienced in conducting social surveys and underwent two days of training for this project. Crop yields were reported by respondents based on local methods of measuring, which were converted to kilograms. Semi-structured interviews were conducted by the first author and two research assistants with 36 male and 36 female respondents selected randomly. The average interview time was 1 h 20 min. Field notes were taken and the three interviewers met immediately after to verify accuracy. Interviews were also conducted with key informants and local and regional administrators .•Agricultural laborer households •Resource-poor agricultural households •Diversified agriculture + NFE households (many combine cultivation with nonfarm employment (NFE) work or business, average 0.67 ha land, most own one cow, modest income)•Commercial agriculture + business households Data collection spanned from June 2014 to December 2016, a period coinciding with severe rainfall aberrations and shocks across the country . Our ana44.1Immediately before and during the 2014–2016 study period, numerous extreme weather events occurred in Rwanda. In the March-May growing season of 2013, rainfall was far below average  and in 2When asked about the optimal food production strategies to counter uncertain rainfall and extreme climate events, respondents pointed to the importance of diverse agricultural systems. As To quantify views on climate-resilient crops, survey respondents were asked to list the three best and three worst crops to grow under drought and heavy rain scenarios. As shown in 4.2Various aspects of Rwanda's land use policies, although folded into CSA programs by LWH, the One Acre Fund, and Rwanda's Government, have undermined these strategies for the mitigation of climate risk in food production. As other studies have pointed out, the intercropping of multiple crop species and varieties is seen by many as a valuable risk mitigation mechanism . Yet thi‘Yes, they have changed completely… in past years we mixed crops so even if a disaster comes there was little problem, but now we have to plant only one crop…if a disaster comes it is all destroyed.’ By locking producers into crop rotations based on regional and national targets, the overall climate resilience of communities is thus reduced. This occurred throughout Rwanda, particularly with maize, which requires rainfall in the second and third month of growth , which are seen by study participants to further exacerbate the risk of financial loss in the event of climatic shocks. Respondents frequently spoke about the decreased resilience to climatic shocks that has resulted from the prohibition of food-producing polycultures. For example: f growth . Maize i‘I will not change because I cannot change. Local leaders told us to grow these crops, even though some years drought occurs and other years there is heavy rain.’The effects of the CIP were widely felt in the study community, as 90 percent of surveyed households altered land use in accordance with the program in 2015. Study participants indicated that they had little choice in whether to abide by these policies (74 percent claimed that their involvement was not voluntary). Moreover, 75 percent of all households (including those not consolidating land) said that the government makes cropping decisions for them. This loss of autonomy presents another challenge in that crops selected by the authorities  are seen to fare the worst in drought and heavy rain scenarios (as discussed in section These preferences for diverse farming systems and low-risk crops are consistent with crop yield data collected at farm-plot level across three growing seasons. We compared the incidence of yield-reducing climatic shocks on the range of crops planted on various field types (fields planted because of the crop intensification program and those planted without influence of the program). While on CIP fields one of the government-selected crops was grown, a key feature of non-CIP fields was that traditional (prohibited) crops were more likely to be grown . Concerning these two field types and climate shocks, statistical analyses reveal that in fields planted under the government’s crop intensification mandate (CIP fields) there is significantly higher occurrence of yield reduction than non-CIP fields. As shown in This differential was especially pronounced in Season 2014B (March to June 2014), when CIP fields exhibit a threefold higher incidence of yield-reduction from climatic shocks in comparison to non-CIP fields. This is likely due to the occurrence of drought during that season, which had a large negative impact in fields planted with maize or wheat under CIP specifications, as these are crops that households less commonly choose to plant on their own. By contrast, Seasons 2 and 3 of the study were marked by late onset of rain and then periods of heavy rain, which respondents pointed out had a particularly negative impact on bean and peas, crops that households do grow traditionally, outside of government cropping mandates. The fact that Season 3 has the highest occurrence of climatic shocks likely owes to a combination of late start to rain (which had a major impact on wheat) followed by heavy rains (which impacted bean and peas).4.3umudugudu. In the community where the CIP is least enforced, median household losses from drought were only 40 percent, compared to losses of more than 50 percent in the other three communities. The overall impacts of the CIP on household coping capacity is further evident in that 30.1 percent of all households reported lower ability to mitigate the 2014 drought compared to previous droughts. Moreover, this change in drought coping capacity varies significantly by household livelihood group. Among households with the lowest resources, who generally have little land and rely on laboring in others’ fields for income, 39.6 percent said their ability to cope with the drought had decreased, compared with only 25 percent of the wealthiest households . Yet this varies across the four study useholds . On the A second aspect of households’ differential vulnerability to climatic shocks lies in the intersections of climate and access to crucial agricultural resources . Qualitative analysis of interviews reveals dynamics between climate risks and willingness to invest in fields. Respondents frequently noted that while maize, bean, and wheat can produce substantial yields, that is only feasible when climatic conditions are ideal and adequate manure and chemical fertilizer are applied. Households with limited access to resources experience these intersecting challenges to a much greater degree than do those with enough resources to buffer losses from unpredictable climate. Quantitative data further illustrate the complexities of how this differential vulnerability to intersecting losses from low fertility and climate shocks is experienced. For example, during the drought of 2014 the disparity between advantaged and disadvantaged households experiencing intersecting challenges of soil fertility and climate in non-CIP fields was only 9.4 percent, while for CIP fields the gap jumped to 27.1 percent. In other words, while drought can affect all fields, these exogenous climatic shocks can interact with endogenous challenges of differential resource access—which are rooted in structural inequalities. This illustrates how Rwanda’s CIP, in combination with uneven access to productive resources, has shaped household vulnerability to climatic shocks. The result is a situation where the disparity among households in terms of vulnerability to climatic shocks has become aggravated by the CIP.The exacerbating of differential resilience to climatic shocks is further evident in the emerging disparities among socioeconomic groups in terms of changes in agricultural production in recent years. 5The above results shed light on who and what is resilient in SSA’s ongoing Green Revolution and in CSA projects that are now frequently linked to programs of intensification. Efforts in Rwanda to standardize the production of key export crops at scale through constructing terraces and irrigation infrastructure, consolidating land, and encouraging the adoption of hybrid seeds and fertilizer have intersected with structural inequalities to introduce substantial climatic risks despite claims that such programs are "climate smart." The form of resilience afforded in these Green Revolution projects hedges on balancing production out over time and space. There is an assumption that even if some fields or communities are unproductive in some years, overall productivity gains in other regions and in other years will offset these losses. Yet, only the wealthiest of study participants, who have substantial land and alternative cash flows, proved resilient to the series of droughts, unpredictable starts to growing seasons, and bouts of torrential rain that occurred between 2013 and 2016. The most marginalized groups, including those with little land and female-headed households, experienced decreased ability to cope with climatic shocks. This form of resilience has fundamental limits in terms of social equity. Rwanda's agricultural development program ensures that national-level food security and economic growth are prioritized over local or intra-household livelihoods.What appears most resilient in SSA's new  Green Revolution is the vision of agricultural development itself: market-led rural transformation through increasing crop yields at the national level. In Rwanda, this Green Revolution model is upheld by the development initiatives of the World Bank and the One Acre Fund, which align closely with the government's ambitions for rural transformation through technoligical and managerial changes. As the Project Completion Report for LWH describes it, the key "factors driving the success of the project" were that the "Government and the Bank were dedicated to a sector-wide rural development and other donors were willing to support LWH's program without variance in project implementation features"  Borlaug Fellowship for Global Food Security. Analysis and writing were supported by the Wellcome Trust, Our Planet Our Health , award number 205212/Z/16/Z.This fieldwork on which this article is based was funded by the The authors have no conflicts of interest to disclose.


For patients requiring open-heart surgery, this raises concern that the use of cardiopulmonary bypass (CPB) may cause a transient immunosuppression with potential to promote the spread and growth of coexisting cancer cells. Further research is needed to know whether the transient immunosuppression associated with CPB can promote the spread and growth of pre-existing cancer cells, emphasizing that lung cancer and skin melanoma have had the most extensive association studies. In conclusion, adverse effects of CPB on cancer prognosis are expected, but have not been confirmed. We read with great interest the article: "Cardiopulmonary Bypass and Cancer Dissemination: A Logical But Unlikely Association" by Braile DM and Évora PRB. In this context, we present a letter to the editor on the potential role of minimally invasive extracorporeal circulation technologies (MiECT) in oncologic cardiac surgery. MiECT include a number of interventions aimed to reduce the clinical impact of CPB and to consequently contain postoperative morbidity and mortality. In the past, different kinds of CPB circuits were defined as "minimally invasive CPB", creating a confused scenario. Recently, the definition of a minimally invasive extracorporeal circulation (MiECC) system was standardized.Several series indicated that surgical stress suppresses the immune system and that the use of CPB, cardiac arrest, and ischemia contributes to this. The most significant contributors to immune suppression are still yet to be determined. It seems that the survival of cancer patients who undergo cardiac surgery is more closely related to the progression of the tumor than the surgical procedure. Reviewing the literature, we believe that in patients with cancer disease candidates for life-saving cardiac surgery procedures, MiECC technique could offer new perspectives in survival compared to conventional CPB. Further studies are needed to strengthen this perspective, between minimally invasive approach and immune preservation.A MiECC system must include: (I) a closed CPB circuit; (II) biologically inert blood contact surfaces; (III) reduced priming volume; (IV) a centrifugal pump; (V) a membrane oxygenator; (VI) a heat exchanger; (VII) a cardioplegia system; (VIII) a venous bubble trap/venous air removing device; and (IX) a shed blood management system. Thus, this multidisciplinary perioperative strategy for attaining "more physiologic" cardiac surgery literally advances MiECC from a circuit to therapy: the circuit is the base, the peripherals  upgrade this to a system, while a multidisciplinary strategy encompasses all and renders MiECC use a holistic approach to cardiac surgery. Such strategy encounters the surgeon's and anaesthesiologist's particular techniques, with implementation of goal-directed perfusion from the perfusionist's perspective and point-of-care heparin/protamine and coagulation management from the anaesthesiologist's perspective. The ultimate goal of such policy when using MiECC is to operate on oncologic and fragile patients and to perform complex procedures as comfortable, in terms of haemodynamic and metabolic integrity, as operating on a low-risk case. This is because a "more physiologic" intraoperative perfusion is of paramount importance in this particular setting for optimizing outcome


Varicoceles are so common in infertile men they are believed to be a leading cause of male infertility . Up to 4Despite this, clinical examinations are seldom performed on men attending for infertility investigations, and hence neither detection of a varicocele nor its treatment is routinely included in the male workup. Although there is strong evidence that varicocele repair improves semen parameters , there In a recent study, Jeremias et al. have sought to identify the impact of varicocele on a more critical sperm health marker than a semen analysis; its DNA . Sperm DTo the best of our knowledge, this is the first study detailing the type of DNA damage in men with clinically significant varicoceles. It provides direct evidence that in men with varicocele DNA damage is oxidatively induced. Equally important, it shows that clinical varicocele causes both single-strand DNA breaks and double-strand DNA breaks; the latter being more severe and difficult to repair by oocyte repair mechanisms. Another novel aspect of their work relates to the inclusion of normozoospermic men -those who have conventional semen parameters within normal ranges. Again, to our knowledge, this is the first study to report that normozoospermic men with clinically significant varicoceles can cause sperm DNA damage even though conventional semen parameters do not show evident abnormalities.Jeremias and co-workers’ study has an important clinical impact as a plethora of studies over the past decade have reported associations between sperm DNA damage inducers, such as ageing and smoking, and an increased risk of childhood cancers and neurological defects in offspring –12. It aIn contrast, several recent reviews have supported the role of varicocele repair in improving male fertility specifically by its improvement to sperm DNA quality –18. AddiA further impediment to providing a full male investigation is the lack of uro-andrologists on fertility clinic teams. This is commonly the case in the UK, although less common in the USA and Brazil. Most UK fertility clinics are staffed by obstetricians, so they are female focussed. Traditionally, these clinicians have little training in the causes of male infertility and hence in the male partner. This required urgent redress as a matter of best clinical practice.A final consideration for the inclusion of varicocele in the male fertility workup is cost-effectiveness. Cost-benefit analyses were reviewed by Yan and co-workers in 2019, concluding that surgical repair of the varicocele is the most cost-effective primary treatment compared to any form of ART .For all these reasons, we ask readers: ‘Is it time to review our traditional male workups based on the latest scientific and economic evidence and provide men with an optimal fertility pathway?


The dissemination of tumor cells to local and distant sites presents a significant challenge in the clinical management of many solid tumors. These cells may remain dormant for months or years before overt metastases are re-awakened. The components of the extracellular matrix, their posttranslational modifications and their associated factors provide mechanical, physical and chemical cues to these disseminated tumor cells. These cues regulate the proliferative and survival capacity of these cells and lay the foundation for their engraftment and colonization. Crosstalk between tumor cells, stromal and immune cells within primary and secondary sites is fundamental to extracellular matrix remodeling that feeds back to regulate tumor cell dormancy and outgrowth. This review will examine the role of the extracellular matrix and its associated factors in establishing a fertile soil from which individual tumor cells and micrometastases establish primary and secondary tumors. We will focus on the role of the lung extracellular matrix in providing the architectural support for local metastases in lung cancer, and distant metastases in many solid tumors. This review will define how the matrix and matrix associated components are collectively regulated by lung epithelial cells, fibroblasts and resident immune cells to orchestrate tumor dormancy and outgrowth in the lung. Recent advances in targeting these lung-resident tumor cell subpopulations to prevent metastatic disease will be discussed. The development of novel matrix-targeted strategies have the potential to significantly reduce the burden of metastatic disease in lung and other solid tumors and significantly improve patient outcome in these diseases. Lung cancer remains the leading cause of cancer death worldwide . Non-smaEffective management of NSCLC is hampered by the late presentation of the disease, when metastatic foci are typically already established. The major sites of non-small cell lung cancer metastasis are the brain 12–47%), bone 16–39%), liver (7–22%), intrapulmonary , pleura 10–13%), thoracic lymph node (29%) and adrenal gland 6–15%) 7%, bone , 9. Whil%, liver % 7%, bon–13%, thoin situ. Conversely, the latter occurs via a conventional metastatic process whereby cells disseminate away from the primary tumor to colonize a niche within the lung that is anatomically distinct from the primary tumor site.Aided by improved detection modalities , 12, lunEmerging evidence from DNA sequencing studies mapping the clonal evolution of lung tumors is providing unprecedented insight into the dynamics of lung tumor outgrowth, as well as distinguishing between tumors arising from intrapulmonary metastases or from independent transformation events. Correlations between multiregional tumor sequencing and smoking-associated behavior suggest that driver gene mutations occur several decades prior to cancer diagnosis  and therThe mechanisms that drive the dormancy and reawakening of lung cancer cells both within the lung and in other secondary organs remain to be precisely defined, however, there is a clear tissue tropism to the induction, maintenance and re-awakening of tumor cell dormancy that occurs in a cancer type-dependent manner , 26. TheThe accredited model of tumor dynamics is that disseminated cancer cells interact with both local and distal stromal and immunological cells through systemic and local signaling to establish niches that support the engraftment and survival of cancer cells. The seed and soil hypothesis states that for successful metastasis to occur, disseminated tumor cells must be compatible with the secondary niches that they go on to colonize. Disseminated tumor cells may be maintained in these metastatic niches in a dormant or quiescent state, and cells that are compatible with their new environment may later re-enter the cell cycle and start proliferating to form metastatic foci in response to intrinsic and microenvironmental cues . The extThe extracellular matrix of the lung incorporates a diverse group of core matrisomal proteins that form the structural basis of the tissue, together with the enzymes responsible for remodeling and processing these molecules, as well as the soluble factors that are associated with this matrix  Figure . TogetheWhile mechanisms of dormancy appear strongly cell-type and context dependent, these pathways largely converge on mitogenic and stress response signaling pathways. In particular, the TGFβ/BMP, FAK, Src, uPA, EGFR, and integrin signaling pathways are integrated with LKB1/AMPK, PI3K and metabolic signaling to modulate ERK/p38, JNK, cyclin and downstream cell cycle regulators to control the entry and exit of cells from the cell cycle , 31, 32 The extracellular matrix composition of the central lung is dominated by fibrillar collagens (primarily collagen types I and II), while the interstitial ECM of the alveoli in the distal lung is a relaxed network of mainly type I and II collagens and elastin . CompareCollagens are a significant component of the lung ECM and altered collagen composition and structure are known to regulate cancer cell dormancy. Primary lung tumors of both the adenocarcinoma and squamous carcinoma subtypes have increased fibrillar collagen deposition and an altered collagen architecture that is consistent with a fibrotic response  Figure . In breaWhilst changes in the composition and architecture are the major collagen alterations in lung tumors, mutations in collagen type V alpha 2 chain (COL5A2) and collagen type II alpha I chain (COL2A1) genes have also been detected in subclonal secondary lung tumors following genomic doubling events in both adenocarcinoma and squamous carcinoma . While sThe collagen composition of tissues is partly determined by the activity of proteases that process nascent collagen molecules for assembly into the 3D environment. Bone Morphogenetic Protein 1 (BMP1) and members of the A Disintegrin and Metalloproteinase with Thrombospondin motifs (ADAMTS) family, which are differentially expressed in NSCLC tumors, are required to cleave the N- and C-termini of the pro-collagen peptide to enable collagen fibrillogenesis and deposition . It is nCollagens, as well as laminin, fibronectin, thrombospondin, osteopontin and other core matrisomal proteins mediate their effects on dormancy by acting as ligands for integrin receptors to activate intracellular proliferation pathways. Integrin receptors are heterodimers of α and β chains that bind to a variety of extracellular matrix molecules, and are the main cellular receptor for collagens. Integrin receptors are capable of bidirectional signaling across the plasma membrane. Intracellular signals regulate the conformation and ligand affinity of the extracellular domain while also mediating intracellular cytoskeletal signaling . For exaThis extensive crosstalk between signaling pathways downstream of integrin receptors generates a network of diverse intracellular signaling pathways that are finely tuned to respond to heterogeneity within the extracellular matrix environment. Specific pairs of α- and β-integrin receptors have different affinities for extracellular matrix components, and enact different downstream signaling events. This creates a signaling program that can be fine tuned to interpret and respond to the subtle shifts in the extracellular environment . The colGlycoproteins are proteins that are covalently modified with carbohydrate groups. They have diverse functions within the primary tumor, pre-metastatic and metastatic niches including the regulation of dormancy and outgrowth. Below we will discuss the role of some of the most well studied glycoproteins involved in primary and secondary lung tumors.Laminin is a heterotrimeric glycoprotein that acts as an important component of the basement membrane in the lung as well as in other tissues . BasemenThe laminin-111 isoform in the lung basement membrane is known to regulate the dormancy of breast cancer cells colonizing the lung . AlbrengThe glycoprotein fibronectin directly interacts with multiple extracellular matrix proteins as well as integrin receptors α3, α5, αV, α8, β1, and β3, which together regulate the structure of fibronectin fibrils, cell-ECM engagement and activate pro-proliferative intracellular signaling programs. Under cellular contraction, tensile forces applied to fibronectin reveal cryptic sites that bind to other fibronectin fibers, inducing fibronectin fibril formation that further stretches the fibers . These sFibronectin expression is increased in primary lung tumor sites and at pre-metastatic sites of breast cancer metastasis to the lung , 66, 67.In addition to its direct stimulation of integrin signaling, fibronectin can indirectly influence growth factor signaling and cell proliferation by interacting with Bone Morphogenetic Protein-1 (BMP-1), Hepatocyte Growth Factor (HGF), Fibroblast Growth Factor 2 (FGF-2), Platelet-derived Growth Factor (PDGF) and latent TGFβ, although this is yet to be demonstrated specifically in NSCLC tumors . It is bTenascin-C is a large multi-domain glycoprotein that undergoes extensive post-transcriptional and post-translational regulation. It is highly expressed in lung development during branching morphogenesis and alveolarization. However, in adult lungs it is only transiently expressed in response to injury . Loss ofTenascin-C is also a ligand for β1-containing integrin receptors and is known to activate pro-proliferative integrin signaling. Together with its close association and interactions with fibronectin, its engagement with integrin receptors is a major mechanism by which this glycoprotein regulates tumor dynamics. Tenascin-C also contains EGF-like domains which can potentially directly activate EGFR signaling . While eHigh expression of Tenascin-C in breast cancer is associated with increased risk of lung metastases, suggesting that it affects more than proliferative signaling in cancer cells. Here Tenascin-C acts in an autocrine manner on disseminated cancer cells to support their self-renewal, survival and lung colonization characteristics. Tenascin-C-mediated breast cancer cell reprogramming inhibits JAK2-STAT5 signaling to enhance MSI1 expression and drive pro-metastatic NOTCH signaling  Figures. WhetherPeriostin is a secreted glycoprotein that has also been shown to induce awakening of dormant cancer cells within the lung. High expression of periostin, as well as the aberrant expression of alternatively spliced isoforms of this gene, are also associated with poor prognosis in primary lung cancer –88. In min vitro, it is not clear if thrombospondin-TGFβ interactions regulate dormancy in the lung and at secondary lung cancer sites in vivo.The glycoproteins of the thrombospondin family, primarily thrombospondin-1 and thrombospondin-2, are produced by immune, vascular and stromal cells within the lung and are known to inhibit the initiation of primary tumors and the outgrowth of secondary tumors in the lung , 91. OneStudies in breast cancer models of lung metastasis have identified that cancer cells with high AXL expression also highly express thrombospondin-2 and this drives TGFβ1-dependent lung colonization . Upon covia p53 activation in fibroblasts within the tumor environment, thereby increasing thrombospondin-1 levels in the local tumor microenvironment. The context dependency of thrombospondin-1’s involvement in lung cancer initiation, primary tumor progression and the establishment of secondary tumors remain to be clarified.The role of thrombospondin-1 in lung tumors, however, remains contentious. Serum and intratumoral levels show conflicting associations with patient outcome –97, whicOsteopontin is a secreted matrix–associated phosphoglycoprotein that is activated by MMP3/7 or thrombin protease , 101. HiProteoglycans have a central protein core from which covalently attached linear repeating glycosaminoglycan chains or sulfated polysaccharides extend outward. Proteoglycans are considered a subclass of glycoproteins that specifically contain unbranched and repeating O-linked carbohydrate molecules called glycosaminoglycans. The major glycosaminoglycan classes are hyaluronan, chondroitin, dermatan, heparin and keratan. Proteoglycans are commonly secreted by cells and are enriched in the basement membrane where they act as nucleating components for the fibrillogenesis of collagens and the assembly of elastin fibers , 109.Versican is a chondroitin sulfate proteoglycan that regulates the perialveolar tissue volume and contributes to alveolar maturation during lung development . Althougvia TLR2, TLR6 and CD14 signaling to induce TNFα and IL6 production that subsequently supports lung colonization , which directly binds hyaluronan , has alsStructural matrisomal proteins in the lung extracellular matrix directly interact with soluble growth factors and ECM degrading enzymes . SecreteMany proteins that associate with the core matrisome regulate dormancy and outgrowth in a tissue- and context-specific manner. The most prominent of these is TGFβ, which is physically tethered to the matrix and is released upon matrix remodeling. The lung has a uniquely high expression of the TGFβ superfamily member BMP4, which promotes the dormancy of disseminated tumor cells within this tissue . In breaThe canonical ligands regulating stemness also interact with the extracellular matrix and modulate the metastatic capacity and dormancy phenotypes of cancer cells at primary and secondary sites. Both lung cancer cells and disseminated cancer cells that colonize the lung are enriched for stemness characteristics . This stThe association of these signaling effectors with the core matrisome in the lung creates a dynamic functional network that directs the behavior of primary and disseminated cancer cells alike. An improved understanding of how the dynamics of these protein-protein interactions influence cancer cell dormancy and dissemination will generate a more complete picture of the role of the extracellular matrix as a functional, as well as a structural component of the tumor microenvironment. The dynamics of extracellular matrix synthesis and turnover, which regulates the release and sequestration of these matrisome-associated factors, is therefore a significant consideration in the functional dynamics of the tumor microenvironment.The extracellular matrix is a dynamic component of the tumor microenvironment that regulates the capacity of tumor cells to migrate away from the primary tumor and colonize local or distant sites to form overt metastases. The structure and composition of the extracellular matrix is remodeled by multiple enzymes, such as the lysyl oxidases, MMPs and ADAMTS families that mediate both the crosslinking and degradation of ECM components. The degradation products of these remodeling processes are far from passive byproducts. Many of these products of catabolic ECM remodeling have individual signaling roles that mediate crosstalk between cell types within the tissue environment or are released systemically to influence the function of multiple organ systems. Therefore the dynamic remodeling by these enzymes significantly contributes not only to the ECM composition within the local tissue environment but also to the functional responses of cells within both the local and systemic environments.Collagen architecture is largely built up by the crosslinking of collagen fibrils to form highly bundled collagen fibers. Collagen crosslinking is initiated by lysyl hydroxylases, which catalyze the intracellular hydroxylation of lysine residues. Lysyl hydroxylase 2 is highly expressed in adenocarcinoma, where it promotes NSCLC metastasis by increasing tumor stiffness to activate cancer cell invasion, PI3K signaling and modulates collagen remodeling –136. TheEnzymes of the lysyl oxidase family catalyze the oxidative deamination of hydroxy-lysine and lysine to reactive aldehydes once the collagen has been secreted into the extracellular compartment. These reactive aldehydes can then spontaneously crosslink neighboring fibers. This lysyl oxidase-mediated collagen cross-linking is essential to the formation of mature collagen fibrils and fibers that underpin the structural integrity of the collagen matrix. This highly crosslinked collagen is also more resistant to MMP–mediated degradation  and the In non-pulmonary cancers, the lysyl oxidase family profoundly promotes the dissemination of cancer cells from the primary site as well as the colonization of and outgrowth at distant sites, including the lung, through direct effects on collagen architecture and tissue biomechanics , 139–144The importance of lysyl oxidases in lung cancer dynamics is dependent on the histological subtype and genomic profile of the tumor. In particular, loss of LKB1, which occurs in 34% of adenocarcinoma and 19% of squamous carcinomas , inducesProteases play an important role in the degradation and turnover of all matrix components in the lung and at distant sites. In the lung, neutrophil-derived MMP9, cathepsin G and elastase cleave laminin-111  and throProteases within the lung environment also cleave ECM components to release growth factor ligands that regulate pro-proliferative intracellular signaling events. For example, BMP1 cleaves latency associated binding peptides thereby releasing TGFβ into the microenvironment to promote dormancy . ConversProteases that directly modify core matrisomal proteins also activate other ECM remodeling enzymes. For example, BMP1 which activates fibrillar pro-collagens by removing their N and C-termini, also cleaves the pro-LOX protein to release the mature active enzyme . This plThe network behavior of matrisomal proteins determines the biomechanical properties of lung tissue. Elevated fibrillar collagen content and higher levels of crosslinking between collagen fibrils in NSCLC tumors increases the mechanical stiffness of the tissue . Mechanoin vitro models, this mechanoresponsive fibroblast activation can persist for several weeks once the matrix stiffness is reduced, suggesting that transient stiffening of lung tissue in response to injury may also induce long lasting effects on cellular behavior that can potentiate tumorigenic processes , which binds to integrin receptors , 81, 82.via β1-integrin signaling in EGFR mutant lung adenocarcinoma . N. N193). The extracellular matrix features that characterize NSCLC patients at high risk of poor outcome outlined above have the potential to be utilized as clinical decision-making tools in determining the most effective therapy for a patient’s condition. In NSCLC, where there are currently no clinicopathological features identifying early-stage patients at high risk of disease recurrence following surgery, there is a clear need to identify the distinguishing characteristics of this population. Transcriptional signatures associating matrisomal gene expression with lung cancer recurrence holds promise that such approaches may robustly identify early stage patients at high risk. This will become more important as early stage diagnoses continue to increase . ImproveThe substantial progress in understanding the extracellular matrix dynamics occurring during primary tumor development and metastatic colonization of many tumor types to date provides hope that this knowledge may improve clinical practice in the future. Although, our understanding of these processes in lung cancer is lagging behind that of other common cancers, such as breast cancer. Of critical importance in realizing this goal will be developing biomarkers of these processes that perform with satisfactory sensitivity and specificity. Moreover, it remains a challenge to develop tests that are capable of extending beyond robust performance on population level data to predict risk for an individual patient. Such readouts must also be readily appropriated to existing clinical management pipelines.This understanding could also establish a path to develop therapies targeting tumor cell dormancy in NSCLC. Dormant cells largely escape immune surveillance and are resistant to conventional and targeted chemotherapies . TherefoA deeper understanding of the role of the tumor microenvironment will also assist in determining which existing therapies are the most appropriate for the patient. It will also be important to determine whether surgical resection in early stage cancers is likely to increase the risk of activating already disseminated tumor cells and therefore worsening the patient prognosis . SimilarHowever, consideration must be given to the impact of such therapies on stromal cells within the tumor microenvironment. For example, cisplatin treatment induces AXL and GAS6 expression by cancer associated fibroblasts to promote the migration of AXL-expressing lung cancer cells . An incrRecent advances in our understanding of how the matrix is impacting tumor cell dormancy has also led to the development of novel therapeutic strategies aimed at maintaining dormancy or eradicating dormant cells.The recognition of common fibrotic mechanisms in idiopathic pulmonary fibrosis and lung cancer has led to interest in repurposing anti-fibrotic IPF therapies to the treatment of lung cancer. Many anti-fibrotic therapies have met limited success in clinical trials for their ability to inhibit metastatic colonization and promote dormancy maintenance. However, the VEGF, PDGF and FGF inhibitor Nintedanib, which is used in the treatment of idiopathic pulmonary fibrosis, has been approved in some jurisdictions as a second line therapy in combination with conventional chemotherapy  in NSCLC and renal cell carcinoma . By blocAdditionally, LOX-neutralizing antibodies that block collagen I deposition and cross-linking have shown utility in preclinical studies targeting metastasis of non-pulmonary tumors to the lung , 143. PrDirectly targeting the extracellular matrix components themselves has also shown promise. Antibodies against the pro-proliferative proteolytic fragment of laminin-111 suppressed the outgrowth of breast cancer metastases in the lungs in a preclinical model , althougOther experimental approaches are targeting key signaling processes downstream of matrix engagement. Suppression of MAPK signaling, or by targeting EGFR, MMP9, amphiregulin, FAK, SRC kinases, ROCK or PI3K, as well as by sustaining or inducing p38 and HOXD10 signaling have proven effective at inducing dormancy in breast and pancreatic cancer models , 204 andOther approaches are using matrix component epitopes to target drugs directly to the tumor site. For example, the collagen-binding properties of lumican have been exploited to target collagen-rich melanoma tumor environments with interleukins  and may While tremendous progress has been made in understanding the complex interplay between cancer cells, the extracellular matrix and the surrounding stromal cells in regulating the dynamics of primary and secondary tumors in many cancer types, the interrelated functions of these components in lung cancer are still being revealed. The complex interplay of ECM components and cell types within the healthy lung, coupled with the highly heterogeneous landscape of lung tumors themselves make this particularly challenging. Defining the phenotypic plasticity of these cell types in healthy and diseased tissue will be fundamental to determining how crosstalk between these cell types orchestrates the extracellular matrix composition of primary and secondary lung tumors. This is particularly the case for fibroblasts and epithelial cells, where lineage-tracing experiments will be invaluable in revealing the extent to which different cell types assume the myofibroblast phenotype in the tumor microenvironment or pre-metastatic niche. Furthermore, as a load-bearing organ, consideration should be given to the mechanical cues that regulate cell behavior within these lung compartments.in vitro and in vivo models that more accurately recapitulate the dynamic ECM remodeling in these tumors will be key to dissecting the contribution of individual cell types and matrix components to the broader network. In particular, robust models of the squamous NSCLC subtype and of metastatic processes in NSCLC more generally are currently lacking. Importantly, directly comparing these models and the genomic features associated with them will clarify the context-dependent cues that are currently preventing the development of an integrated model of these processes. It is not currently clear how quickly the ECM is remodeled within the healthy or diseased lung, how long the remodeled matrix persists in a given state, or the temporal hierarchy of how these ECM features evolve over time. An understanding of how early ECM remodeling occurs in the initiation of lung tumors, and whether this tumor-associated ECM remodeling persists following remission will be fundamental to understanding the temporal dynamics of lung tumor progression and relapse.The development of Our current understanding has identified the impact of ECM composition at the level of individual ECM components. However, the ECM acts a three-dimensional network of matrisomal proteins together with matrisome-associated factors and signaling effectors. An improved understanding of the role of the ECM in regulating dormancy and outgrowth will rely on clearly defining the protein-protein and protein-carbohydrate interactions that form these networks and how individual nodes manipulate the collective three-dimensional architecture of the ECM. High-resolution optical imaging and spatial proteomic technologies to map these interactions will be invaluable in defining these spatial relationships.Historically, the late presentation of NSCLC has obscured our understanding of early stage disease processes. Furthermore, there is currently no way to establish when tumor cell dissemination establishes intrapulmonary and distant dormant micrometastases to facilitate the direct study of the ECM in these events. However, improved early detection strategies are increasing the proportion of patients diagnosed with early stage disease, and thereby providing opportunities to gain insight into these early dynamics. The analysis of these early stage tumors using improved sequencing and proteomic technologies will also shed light on the true incidence and clonal evolution of the primary and metastatic tumors. Accurate determination of the incidence of intrapulmonary metastases and the contribution of ECM-driven processes to recurrence following surgery will be fundamental to improving patient outcome in early stage disease. Similarly, an understanding of how extracellular matrix remodeling in chronic lung diseases such as chronic obstructive pulmonary disorder and idiopathic pulmonary fibrosis affects the transformation of lung epithelia and the progression of established NSCLC tumors may partly explain why these conditions are associated with an elevated risk of developing these tumors. Inhibition or reversal of ECM remodeling in these fibrotic diseases may be a crucially important approach to prevent lung cancer initiation in these patients.Taken together, these developments in understanding the structural and functional role of the ECM in NSCLC progression will reveal novel potential therapeutic strategies that are able to identify patients at high risk of developing recurrent disease as well as the optimal therapeutic approaches based on both the cell-intrinsic and -extrinsic mechanisms operating within the tumor microenvironmental rather than focusing on cell-intrinsic somatic genomic alterations alone. Novel therapeutic approaches that sustain disseminated cells in a dormant state, or awaken and eradicate the residual disease, will see lung cancer become a manageable chronic illness and ultimately a curable condition.AP and TC contributed equally to the conception, writing, and reviewing of this manuscript. Both 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.