Although intravesical botulinum toxin type A (BoNT-A) injection for functional bladder disorders is effective, the injection-related problems—such as bladder pain and urinary tract infection—make the procedure invasive and inconvenient. Several vehicles have recently been developed to deliver BoNT-A without injection, thereby making the treatment less or non-invasive. Laboratory evidence revealed that liposome can carry BoNT-A across the uroepithelium and act on sub-urothelial nerve endings. A randomized placebo controlled study revealed that intravesical administration of liposome-encapsulated BoNT-A and TC-3 hydrogel embedded BoNT-A can improve urinary frequency, urgency, and reduce incontinence in patients with overactive bladders. A single-arm prospective study also revealed that intravesical administration of TC-3 hydrogel embedded BoNT-A can relieve bladder pain in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). We recently administered suprapubic energy shock wave (ESW) after BoNT-A intravesical administration in six patients with IC/BPS. Although pain reduction and symptom improvement were not significant, immunochemical staining showed cleaved synaptosome-associated protein 25 in the bladder after the procedure. This suggests that ESW can promote passage of BoNT-A across the uroepithelium. In conclusion, using vehicles to intra-vesically deliver BoNT-A for functional bladder disorders is promising. Further studies are necessary to confirm the efficacy and explore novel applications. In summAll patients tolerated the procedure well without any complications; however, the therapeutic effect was not significant. Reduction of pain on the visual analog scale, and symptoms score in Interstitial Cystitis Symptom Index and Problem Index, were not significantly improved in this pilot study with six patients . Two of We summarized current clinical evidence of non-invasive intravesical BoNT-A delivery for patients with functional bladder disorders in the Using vehicles to intra-vesically deliver BoNT-A for functional bladder disorders is promising. Further studies are necessary to confirm the efficacy and explore novel applications.


This study aimed to identify new characteristics of elderly onset large-vessel vasculitis (EOLVV) by focusing on human leucocyte antigen (HLA) genotype, polymyalgia rheumatica (PMR), and affected vascular lesions observed on positron emission tomography/computed tomography (PET/CT) imaging.We retrospectively studied 65 consecutive Japanese patients with large-vessel vasculitis (LVV) who had extracranial vasculitis lesions and underwent PET/CT imaging. PET/CT images were assessed using the semi-quantitative PET visual score of each affected vessel, and the PET vascular activity score (PETVAS) and number of affected vessels were calculated. Subjects were subsequently grouped based on age at onset, superficial temporal artery (STA) involvement, and presence of PMR and compared each group according to HLA genotype. Unsupervised hierarchical cluster analysis was used to identify the patients with similar characteristics in terms of affected vascular lesions detected through PET/CT imaging. The clinical characteristics and PET/CT findings of the population newly identified in this study were examined.Twenty-seven patients with EOLVV did not meet the American College of Rheumatology 1990 criteria for giant cell arteritis (GCA) and Takayasu arteritis and were considered as unclassified EOLVV (UEOLVV). The unsupervised hierarchical cluster analysis revealed that UEOLVV with PMR and large-vessel GCA (LV-GCA) formed a cluster of LVV with GCA features  when restricted to patients who were HLA-B52-positive. Patients who were HLA-B52-positive with LVV and GCA features had similar clinical characteristics and patterns of affected vessels and presented with diffuse LVV lesions. HLA-B52-positive patients who had LVV with GCA features also presented with higher PETVAS, more affected vessels, and lower rates of biologics usage and relapse compared to HLA-B52-positive patients with TAK.Patients who had UEOLVV with PMR had similar characteristics to patients with LV-GCA. Patients who were HLA-B52-positive and had LVV with GCA features presented with diffuse vascular lesions and may comprise a core population of Japanese patients with EOLVV. The findings of HLA-B52 positivity and diffusely affected vessels in patients with EOLVV can be considered as suspicious findings of LV-GCA.The online version contains supplementary material available at 10.1186/s13075-021-02618-4. Large-vessel vasculitis (LVV) can be generally categorized into giant cell arteritis (GCA) and Takayasu arteritis (TAK) based on the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides , 4. FurtThe human leucocyte antigen (HLA) genotype, the presence or absence of polymyalgia rheumatica (PMR), and the distribution of affected vascular lesions are all important in distinguishing between both diseases. HLA-B52 and HLA-DR4 are known characteristic alleles that are associated with TAK and GCA beyond ethnicity, respectively , 10. EthImaging is important for diagnosing and evaluating LVV considering the difficulty of diagnostic biopsies in numerous large vascular lesions, as well as the similar histopathological findings of TAK and GCA . RecentlThe present study therefore aimed to determine PET/CT findings that can be used to distinguish LV-GCA from TAK and identify new characteristics of LV-GCA related to the HLA genotype, presence of PMR, and affected vascular lesions detected through PET/CT imaging.A retrospective study was conducted at Kyushu University Hospital and Kurashiki Central Hospital. After differentiating diseases that can cause large-vessel inflammation, such as IgG4-related aortitis, inflammatory aortic aneurysm, infectious aortic aneurysm, syphilitic aortitis, and vascular involvement in Behcet’s disease, a total of 72 consecutive Japanese patients diagnosed with LVV who underwent PET/CT imaging at our department between April 2004 and February 2020 were enrolled herein. After excluding seven patients with isolated cranial GCA, 65 patients with extracranial LVV lesions were ultimately analyzed. LVV with extracranial lesions can be diagnosed based on any of the following criteria: inflammatory findings on PET/CT, vascular wall thickening and damage on CT and magnetic resonance imaging, or postoperative pathological diagnosis. TAK and GCA were classified using the American College of Rheumatology (ACR) 1990 classification criteria , 7. GCA After retrospectively reviewing patient data, the following information were collected from medical records: age, sex, symptoms, clinical characteristics, laboratory findings, imaging, histological results, medications, and outcomes. Laboratory data, including platelet count, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR), were collected upon PET/CT imaging in patients with newly diagnosed and untreated LVV. HLA genotypes and anti-phospholipid antibody (aPL) during the clinical course were also determined. The genotyping of HLA-B and HLA-DR allele groups was determined by polymerase chain reaction-reverse sequence specific oligonucleotide method using the Luminex assay system and HLA typing kits. aPL positivity was confirmed based on any positivity for lupus anticoagulants , IgG anti-cardiolipin antibodies (measured using enzyme-linked immunosorbent assay), or IgG anti-cardiolipin-β2 glycoprotein 1 complex antibodies (measured using enzyme-linked immunosorbent assay).As outcomes, additional biologics usage and disease relapse from their onset to February 2020  were investigated. Disease relapse was defined based on Kerr’s definition for TAK or recurrence of symptoms attributed to active GCA as previously reported , 23.18F-fluorodeoxyglucose (FDG) PET/CT images were obtained using an integrated PET/CT scanner Discovery STE  and Biograph mCT. Prior to FDG administration, patients fasted for at least 4 h, after which scans were conducted from the middle of the thigh to the top of the skull 60 min after FDG administration.This study compared PET/CT findings in patients with newly diagnosed and untreated LVV to properly evaluate inflammatory findings without treatment effects. One or two nuclear medicine specialists interpreted the PET/CT images and documented the presence of vasculitis lesions. Two experienced rheumatologists then blindly reviewed the patients’ PET/CT scan and visually determined a semi-quantitative PET visual score on each arterial territory using a pseudo-color spectrum scale  , 24, 25.P values < 0.05 indicating statistical significance.Data were reported as mean and standard deviation, median and interquartile range, or number and percentage. Comparisons between two groups were performed using the Wilcoxon rank sum test for continuous variables and either the chi-square test or Fisher’s exact test for categorical variables. Multiple group comparisons were performed using the Steel–Dwass test. Unsupervised hierarchical cluster analysis with Ward's method was performed using the PET visual score of each of the 15 specific extracranial arterial territories. All analyses were performed using JMP statistical software , with A total of 65 patients who had LVV with extracranial LVV lesions were divided into two groups according to age, with a cutoff of 50 years: 25 patients with young-onset LVV diagnosed as TAK and 40 patients with EOLVV. Among the 40 patients with EOLVV, 13 were diagnosed with LV-GCA, whereas the remaining 27 were categorized as UEOLVV , most of whom had HLA-B52, exhibited a significantly increased number of extracranial vascular lesions of LVV compared to those with TAK. The aforementioned findings suggest that HLA-B52-positive LVV with GCA features, which is characteristic to diffuse vasculitis, comprises a core population of patients with EOLVV.The current study showed that the population of UEOLVV with PMR was very similar to that of LV-GCA  and distinct from that of UEOLVV without PMR. Patients who had UEOLVV with PMR exhibited similar clinical findings to those with LV-GCA, especially regarding jaw claudication and axillary artery involvement, which are characteristic features of GCA , 20. AddThe present study also demonstrated that patients who had LVV with GCA features demonstrated a higher prevalence of HLA-B52, a disease susceptibility allele of TAK, compared to patients who had UEOLVV without PMR. The findings indicate that HLA-B52 is not a specific finding in patients with TAK and is associated with a population of EOLVV. Among HLA-B52-positive patients, those who had LVV with GCA features exhibited different clinical characteristics, clinical courses, and PET/CT findings compared to those with TAK, indicating that the two diseases are still distinct populations even after limiting our analysis to those with HLA-B52. These findings suggest that the role of HLA-B52 in LVV with GCA features may be different from its role as a disease susceptibility allele in TAK.HLA-B52-positive patients who had LVV with GCA features uniformly exhibited the most extensively affected vessels based on the number of affected vessels detected on PET/CT. The results of this study suggest that HLA-B52-positive patients with PMR or cranial GCA, which have traditionally been considered overlapping pathologies , are likThis study showed that patients who were HLA-B52-positive and had LVV with GCA features exhibited lower rates of biologics usage and relapse compared to patients who were HLA-B52-positive with TAK, who were more also likely to be refractory to treatment or experience relapse compared to the HLA-B52-negative ones. This was consistent with previous reports , whereasThe present study showed that among patients with UEOLVV, those with PMR exhibited more diffuse vascular lesions compared to those without PMR, which is remarkable in HLA-B52 carriers. PET/CT can possibly be used to identify the potential presence of LVV lesions . ReportsThe current study has some limitations worth noting. First, this study had a small sample size and was limited to Japanese patients. Thus, our results need to be verified in a multiracial study with a larger sample size. Second, this was a retrospective study, with lacking HLA measurements and a potential for hindsight bias. The treatment course was also studied backward, and treatment selection was left to the discretion of each attending physician. As such, further prospective studies are needed. Third, the mechanism by which HLA-B52 is involved in the pathogenesis of diffuse LVV with GCA features also needs to be investigated in the future. Lastly, long-term outcomes, such as vascular damage were not assessed. Further studies on the distribution of vasculitis and vascular damage may help predict future vascular damage in LVV.The current study showed that patients who had EOLVV without STA involvement but with PMR demonstrated similar patient backgrounds and vessel distributions (observed via PET/CT) to patients with LV-GCA who satisfied the 1990 ACR classification criteria. Moreover, HLA-B52-positive patients who had EOLVV with PMR and/or STA involvement presented with diffuse vascular lesions and may comprise a core population for LV-GCA in among Japanese individuals. Thus, the findings of HLA-B52-positivity and diffusely affected vessels, as well as those of PMR, in patients with EOLVV can be considered as suspicious findings of LV-GCA.Additional file 1.


The lesion of the sternum showed a lobular appearance, a shell-like periosteal reaction, and matrix calcifications  and exhibited high T2-weighted signal intensity (F) and septonodular contrast enhancement (G) on magnetic resonance imaging. Given this morphological appearance, metastasis seemed unlikely and the subsequent biopsy and surgery confirmed the diagnosis of a grade 3 chondrosarcoma. Immunohistochemistry showed that PSMA was mainly expressed in small intralesional blood vessels/capillaries . This is in line with previous reports demonstrating high PSMA-expression in vascular regions [PET imaging targeting the prostate membrane-specific antigen (PSMA) has demonstrated high potential in localizing disease in prostate cancer. In addition to prostate cancer, both benign and malignant lesions have been reported to highly express PSMA . Here regions , 5.In summary, this case illustrates the potential pitfalls in PSMA-ligand PET-imaging given that PSMA-expression is also present in non-prostate cancer lesions and highlights the necessity of thorough analysis of the accompanying cross-sectional imaging modality.


The aim of this study is to investigate post-COVID-19 antibody titers in patients who received convalescent plasma (CP) in addition to standard-of-care treatment.Hospitalized COVID-19 patients who received CP in addition to standard care were retrospectively investigated. Patients who received CP with a recorded total COVID-19 antibody test result after treatment were included. From among hospitalized COVID-19 patients who received only standard care with a recorded total COVID-19 antibody test result, a control group matched for age, gender, and comorbidities was formed. Total COVID-19 antibody index levels were compared.Thirty-three CP recipients were enrolled in the study. The control group consisted of 34 age-, gender-, and comorbidity-matched standard-care patients. Median total COVID-19 antibody index levels were significantly reduced in the CP group.Although CP therapy may have benefits for disease outcome, its potential ability to hamper long-term immunity may be a problem. Convalescent plasma (CP) therapy is the transfusion of plasma containing polyclonal antiviral antibodies, obtained from recently ill donors who have fully recovered with sufficient antibody responses. Potential mechanisms of action for CP are virus neutralization, antibody-dependent virolysis, antibody-dependent antigen presentation, antibody-dependent cellular toxicity, and complement activation . EnhanceEndogenous antibodies produced by the host in COVID-19 have protective effects against reinfection. Although early administration of CP seems to have beneficial effects on outcomes in COVID-19, it is unclear whether CP therapy alters the endogenous antibody production and hampers long-term humoral immunity against the virus. In this study, we aim to investigate post-COVID antibody titers in patients who received CP in addition to standard-of-care (SOC) treatment and compare them to those of patients who received only SOC treatment.This study was conducted as a single-center, retrospective, case-control study. Ethical approval of the study was obtained from the Ethics Committee of Ankara City Hospital.Hospitalized COVID-19 patients who received CP therapy in addition to the SOC approach from Ankara City Hospital’s Internal Medicine Inpatient Clinic between August 15 and December 31, 2020, were retrospectively investigated. The COVID-19 diagnosis was confirmed with the presence of a recorded positive SARS-CoV-2 real-time reverse transcription polymerase chain reaction (RT-PCR) test from a nasopharyngeal swab for every patient. Among patients with positive PCR results, subjects who received a total of at least 400 mL of CP obtained from donors  with recorded test results for total COVID-19 antibody against the S1 antigen  after PCR positivity were included in the study. Index values of COVID-19 total Ig over 1 are accepted as positive for this kit. Our center reported all values over 10 as >10; therefore, patients with Ig levels of >10 were recorded as having levels of 10. Data regarding demographics and comorbidities were recorded for all CP recipients. From among hospitalized COVID-19 patients who received only SOC treatment during the same period of time with recorded total COVID-19 antibody test results, an age-, gender-, and comorbidity-matched control group was formed.The SOC approach comprised oxygen support, hydroxychloroquine, favipiravir, low-molecular-weight heparin, anticoagulants, and additional anti-inflammatory treatment when indicated in accordance with the COVID-19 guidelines of the Turkish Ministry of Health . LikewisTotal COVID-19 antibody index levels and days from symptom onset at the time of COVID-19 antibody work-up were recorded for both groups.Statistical analyses were performed using SPSS 22 . The normality of variables was investigated by Shapiro-Wilk test. Continuous variables were presented as median and interquartile range (IQR). Categorical variables were presented as number and percentage. The Mann-Whitney U test was used for comparison of continuous variables according to normality. For comparisons of categorical variables, the chi-square test was used. Values of p<0.05 were considered statistically significant.Of 67 recipients of CP in addition to SOC treatment, 33 patients with total COVID-19 antibody test results were enrolled in this study. The control group consisted of 34 age-, gender-, and comorbidity-matched SOC patients with total COVID-19 antibody test results. Demographics, comorbid diseases, duration of symptoms at the time of COVID-19 antibody work-up, and total COVID-19 antibody titers are presented in Our results demonstrate a significantly reduced total COVID-19 antibody response in CP recipients.CP is obtained from recovered COVID-19 patients who have developed humoral immunity, containing neutralizing antibodies (NAbs) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) capable of pathogen clearance from peripheral circulation and pulmonary tissues . NAbs paCP therapy may enhance viral clearance and provide better disease outcomes, particularly when administered in early stages of infection ,20. HoweThe small sample size and retrospective nature of this study were the major limitations. Disease severity at admission or onset of CP treatment was not evaluated. Furthermore, there may have been undetected variations in Ig levels of CP solutions since Ig levels were not measured. Finally, our center reported COVID-19 total Ig values over 10 as >10; therefore, patients with higher Ig levels were not evaluated precisely, which would have further reflected the altering effects of CP on endogenous Ig production. Nevertheless, to our best knowledge, this is the first study to evaluate effects of CP therapy on endogenous antibody production in COVID-19.In conclusion, although CP therapy may have benefits for disease outcomes, its potential to hamper long-term immunity and increase the risk of reinfection may be a problem, since the pandemic is still far from being under control globally.


Allogeneic hematopoietic stem cell transplantation  is a curative treatment for hematologic malignancies. Acute and chronic graft-versus-host disease (GvHD) are the major immune-mediated complications after alloHSCT. However, there is controversy whether neurologic complications after alloHSCT might represent manifestations of GvHD. We report three patients who acquired distinct, severe immune-mediated peripheral or central nervous system diseases after alloHSCT without other, concomitant GvHD manifestations. One patient had been diagnosed with B-cell chronic lymphocytic leukemia and two patients with high risk myelodysplastic syndrome. Patient #1 presented as LGI1- and GAD-IgG positive immune-mediated encephalitis, patient #2 was diagnosed with MOG-IgG positive encephalomyelitis, and patient #3 had chronic inflammatory polyneuropathy associated with SSA(Ro)-IgG positive Sjögren’s syndrome. 100% donor chimerism was detectable in the peripheral blood in all three. The specific antibodies were undetectable in donors’ and patients’ blood before alloHSCT suggesting that the antibodies had arisen from the transplanted donor immune system. Early intensive immunotherapy led to improvement of clinical symptoms and stability of the neurological disease, however, at the cost of losing the graft-versus-malignancy effect in one patient. In conclusion, we provide evidence of isolated, severe allo-immune diseases of the peripheral and central nervous system as complications of alloHSCT (“neuro-GvHD”). Interdisciplinary surveillance and thorough diagnostic work-up are needed for early diagnosis and treatment of neuro-immunologic complications after alloHSCT to improve the otherwise poor outcome. A recently published systematic review with meta-analysis evaluating 57,972 patients from different study designs revealed a relevant incidence of neurologic complications after alloHSCT2. The most important triggers and risk factors for neurologic complications after alloHSCT are drug-, radiation- and metabolic-related toxicity, infections , cerebrovascular and immune-mediated events3. Acute and chronic graft-versus-host diseases (GvHD) are the major immune-mediated complications after alloHSCT. Other immune-mediated complications, such as thyroiditis, rheumatoid arthritis or systemic lupus erythematosus (SLE) can occur4. Immune-mediated neurologic complications after alloHSCT are rare and often associated with poor outcomes. In a retrospective study with 3305 patients, only twelve (0.4%) developed an immune-mediated neuropathy following alloHSCT5. Another large retrospective study with 1484 patients after alloHSCT detected 3 patients (0.2%) with acute demyelinating encephalomyelitis and three further patients (0.2%) acquiring an acute inflammatory neuropathy6. These low incidence rates are supported by the aforementioned meta-analysis with a pooled incidence of immune-mediated neurologic complications including GvHD of 0.6%2. While GvHD is caused by the transplanted allo-immune system, the mechanisms of other immune-mediated complications including those affecting the nervous system are controversial and may involve both allo- and auto-immune responses. For example, myasthenia gravis is a well characterized antibody-related neurological complication after alloHSCT that usually occurs in context of GvHD8. Early diagnosis and treatment of neuro-immunological complications after alloHSCT may be very challenging because symptoms overlap with typical post HSCT complications such as toxicity-related polyneuropathy or fatigue.Allogeneic hematopoietic stem cell transplantation  provides a curative option for many life-threatening diseases, especially hematologic malignancies. Neurologic complications have been shown to significantly increase the morbidity and mortality after alloHSCTHere, we report three allotransplanted patients with distinct antibody-associated neurologic diseases having occurred in the absence of clinical signs of concomitant GvHD.AlloHSCT was performed at the Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, and neurologic complications were treated at the Department of Neurology, both at Hannover Medical School, Germany. The study was approved by the ethics committee of the Hannover Medical School, Germany (no. 1322-2012). All research was performed in accordance with the Declaration of Helsinki. All patients gave written informed consent for publication.9.CSF was obtained via lumbar puncture and immediately analyzed in the Neurochemistry Laboratory of the Department of Neurology as reported previously10.For monospecific testing on the presence of human IgG antibodies to neuronal or glial cells antigens, recombinant cell-based assays were used . Biochips with a mosaic of HEK293 cells transfected with several neuronal surface antigens, i.e. leucine-rich glioma-inactivated protein 1 (LGI1) and myelin oligodendrocyte glycoprotein (MOG), were co-incubated with diluted patients’ sera, followed by fluorescent secondary anti-human antibodies and assessment using fluorescence microscopy. Anti-glutamic acid decarboxylase (GAD) autoantibodies were detected using immunoblots with recombinant antigens  for screening test and followed by indirect immunohistochemistry using commercially available cerebellum primate slides  for verification test in accordance with the manufacturer´s instructions. Antibody titration was carried out by indirect immunofluorescence (LGI1- and MOG-IgG) or indirect immunohistochemistry (GAD-IgG) through increasing dilution of the patient sample. The starting dilution was 1:10 (LGI1- and MOG-IgG) or 1:100 (GAD-IgG) for serum and undiluted for CSF. The samples were rated by two independent investigators who were blinded for the clinical data. Extractable nuclear antigens, like anti-SSA(Ro)-antibodies, were detected by ELISA12.In accordance with the recommendations of the International Federation of Clinical Neurophysiology each standardized electrodiagnostic examination included at least one median, ulnar, peroneal, tibial, and sural nerve conduction using superficial stimulators and recording electrodesPatients with suspected central nervous system (CNS) involvement underwent a multisequence brain (patient #1 and #2) and/or spinal (patient #2) MRI protocol obtained on a 3 T or 1.5 T whole body MR system. The brain MRI protocol included a 3D fluid-attenuated inversion recovery (FLAIR) with multiplanar reconstructions, axial T2-weigthed, axial diffusion-weighted imaging (DWI), susceptibility-weighted images (SWI), and contrast-enhanced T1-weighted images. The spinal cord protocol included sagittal short tau inversion recovery, T2-weighted and contrast-enhanced T1-weighted images, as well as axial T2-weighted images. All images were evaluated by an experienced neuroradiologist with special expertise in the field of inflammatory diseases of the CNS.+ and CD8+ T cells with short tandem repeat polymerase chain-reaction as previously described13. CD4+ and CD8+ T cells were isolated by magnetic separation using the MicroBeads Kit and MACS Column  according to the instructions of the manufacturer. The purity of the positive selected cell fraction was determined by FACS analysis, ranging between 91 and 97%. Genomic DNA was isolated using the QIAamp DNA Micro kit .Chimerism analysis was performed on full blood and on isolated CD4The study was approved by the ethics committee of the Hannover Medical School, Germany (no. 1322-2012). All research was performed in accordance with the Declaration of Helsinki.All patients gave their consent to participate and written informed consent for publication.A 54-year-old male patient developed myoclonic jerks in the left shoulder 4 years after alloHSCT for B-cell chronic lymphocytic leukemia  followed by five cycles of immunoadsorption, tapered oral steroids, and rituximab every six months. Motoric complaints remitted completely, the visual acuity recovered successively, and no new neurologic deterioration occurred during 31 months of follow-up under regularly administered rituximab treatment. However, after the fifth course of rituximab, full donor chimerism was suddenly and completely lost, and the patient was again diagnosed with myelodysplastic/myeloproliferative syndrome, albeit in an earlier stage. The regular neurological treatment was therefore changed to high-dose immunoglobulins.A 65-year-old female patient was referred to our neurological department due to progressive left-sided choreatiform movement disorder, hemiparesis on the right, and visual loss on both eyes starting one month earlier. Onset of neurological symptoms was on day 201 after alloHSCT for high risk myelodysplastic/myeloproliferative syndrome. Post-transplant complications had included mild and transient acute GvHD of the skin at four months and delayed engraftment failure which was successfully treated by a T-cell-depleted stem cell boost five months after alloHSCT , CD19ls Table .Table 2DWe report three allotransplanted patients with severe, distinct antibody-associated neurologic diseases starting on days 201, 343 and 1485 after alloHSCT. Due to the stigmatizing movement disturbances and the associated high psychological strain, the diagnosis of neuro-immunologic diseases in patients #1 and #2 was barely delayed. With a less obvious symptom constellation (increasing paresis and numbness in patient #3), early diagnosis can be hampered or mimicked by the large variety of complications associated with alloHSCT, such as infections or drug-induced toxicities. The three patient examples outlined are the only isolated neuro-immunological complications we have encountered in all of our 1516 consecutive alloHSCT patients since 1995, amounting to an incidence of 0.2%. The rarity of neuro-immunological complications after alloHSCT underscore the need for prospective neurological surveillance of all transplanted patients with early interdisciplinary case discussion and detailed clinical and paraclinical assessment to avoid misdiagnosis and prevent long-term sequelae. This might also help to identify new risk factors for the complex field of neurologic complications after alloHSCT in order to prevent or counteract them.All neuro-immunologic diseases were antibody-associated, and intensive immunotherapy including steroids, antibody-eliminating immunoadsorption, intravenous immunoglobulins and/or B cell depletion by rituximab led to improvement and disease stability in all three patients. Nevertheless, the pathophysiological mechanisms of the outlined neuro-immunologic diseases remain a matter of debate.Considering the follow-up of 29–33 months without recurrence of malignancy after onset of immune-mediated neurologic disease, there is no evidence of paraneoplastic phenomena so far. Moreover, the detected antibodies are not known in a paraneoplastic context.In patient #3, a toxic drug-induced neuropathy could be suspected due to the temporal correlation with the occurrence of the first neuropathic complaints; however, the rapidly progressive course after termination of the neurotoxic medication, the association with the diagnosis of Sjögren's syndrome and the stabilizing effect of immunoglobulins with transient worsening after an intravenous immunoglobulin-therapy pause, after which the clinical condition could only be stabilized by resuming intravenous immunoglobulin treatment, suggest an inflammatory genesis.17.The delayed neuro-immune complication in patients #1 (4 years) and #3 (1 year) might be due to thymic damage with altered central tolerance mechanisms−/− constellation, i.e. with negative CMV serology in both recipient and donor, which only accounts for around 7% of all alloHSCT18. As previously shown, T cells regenerate with considerable delay after alloHSCT in the absence of CMV-specific cytotoxic T cells19. The disease association with antibodies and the treatment response to B cell-depleting therapies in our patients suggests a B cell driven pathology. It may be speculated whether a predisposition of low T cell levels may favor an excessive pathological activation of B cells with the development of antibody-mediated disease.Interestingly, all three patients were transplanted in a CMV21. Autoimmune encephalitides associated with antibodies against neuronal cell-surface proteins are relatively novel clinical entities. Since 2007, new antibodies are identified every year22. It may be hypothesized that some devastating encephalopathies in patients after alloHSCT without evidence of an infectious agent might be caused by currently unknown antibody-mediated diseases. Therefore, in cases of unexplained encephalopathies, a comprehensive antibody testing should be performed in an experienced laboratory whenever possible, as lack of or delayed immunotherapy may lead to severe sequelae or even death23.To our knowledge, only two other antibody associated cases with encephalitis after HSCT have been described in the literature to dateAll three patients described in this report had previously suffered from transient acute GvHD and accordingly showed complete donor chimerism Table . However24, which were altogether lacking in our three patients. CNS manifestations are omitted in these consensus criteria, but a number of cases combined with typical GvHD have been reported by others28. Furthermore, several reports of CNS manifestation without signs of systemic GvHD indicate a possible independent immune-mediated side effect after alloHSCT30, similar to our patients. Thus we are convinced, that the reported complications in our three patients represent isolated, allo-immune neurological disease (“neuro-GvHD”)27. In contrast, the possibility of an auto-immune-mediated disease driven by a small number of residual recipient plasma cells seems very unlikely. As previously published, a small percentage of plasma cells originating from the recipient can persist in the host organism and full plasma cell chimerism may not be reached in half of the patients after 1 year31. Nevertheless, none of our patients had shown the disease-related antibodies in the serum prior to alloHSCT, proposing that the complications were not caused by persisting recipient derived plasma cells surviving the conditioning before alloHSCT. Furthermore, disease-related antibodies were detectable in none of the donor sera before alloHSCT suggesting that the disorders were not caused by pre-existing antibodies transplanted from the donors. Only 1 of 3 patients had 5% residual recipient-derived B cells, while the 2 others displayed full chimerism in the B cell compartment (see Table According to the consensus criteria of the National Institute of Health 2014, the diagnosis of any neurological manifestation of chronic GvHD requires the simultaneous existence of at least one typical diagnostic manifestation of chronic GvHD or at least one characteristic manifestation with a suitable additional test result32, therapies against neuro-GvHD.Finally, the tilt and complete drop of full donor chimerism observed in patient #2 after rituximab suggests that the MOG-IgG associated encephalomyelitis had been due to a graft-versus-host mechanism which was lost during treatment—unfortunately together with its graft-versus-malignancy effect. This may also serve as a caveat and underscore the need to develop more specific, e.g. kinase inhibitor-basedIn conclusion, early, intermediate, and late onset of antibody-mediated severe immune-mediated diseases of the peripheral and central nervous system can occur after alloHSCT, which may represent neuro-GvHD with or without concomitant other GvHD manifestations. Beneficial long-term outcome based on early and intensive immunomodulatory therapy can be achieved in otherwise serious neurological autoimmune diseases that usually cause severe disability within a short period of time. Thus, a systematic, prospective approach with intense interdisciplinary exchange during follow-up of alloHSCT patients is needed to ensure early diagnosis of neurological complications. The scarce knowledge of the underlying pathophysiology on immune-mediated diseases after alloHSCT underlines the need for further clinical and experimental research in this field.Supplementary Video 1.Supplementary Information.


Exosomes are small membrane vesicles of endocytic origin containing cytokines, RNAs, growth factors, proteins, lipids, and metabolites. They have been identified as fundamental intercellular communication controllers in several diseases and an enormous volume of data confirmed that exosomes could either sustain or inhibit tumor onset and diffusion in diverse solid and hematological malignancies by paracrine signaling. Thus, exosomes might constitute a promising cell-free tumor treatment alternative. This review focuses on the effects of exosomes in the treatment of tumors, by discussing the most recent and promising data from in vitro and experimental in vivo studies and the few existing clinical trials. Exosomes are extremely promising as transporters of drugs, antagomir, genes, and other therapeutic substances that can be integrated into their core via different procedures. Moreover, exosomes can augment or inhibit non-coding RNAs, change the metabolism of cancer cells, and modify the function of immunologic effectors thus modifying the tumor microenvironment transforming it from pro-tumor to antitumor milieu. Here, we report the development of currently realized exosome modifiers that offer indications for the forthcoming elaboration of other more effective methods capable of enhancing the activity of the exosomes. Biological cell-to-cell interactions take place to preserve the homeostasis of the organisms. Extracellular vesicle (EV)-intermediated cell communication has particular importance in this field as these elements’ capacity to carry and deliver a diversity of substances from the generating cell to recipient cells .Exosomes are nanometer-sized EVs generated by the internal budding of the membrane of endosomal multivesicular bodies. Exosomes were previously considered ‘trash bags’ for cellular elements to reject discarded proteins. Instead, in the last few years, they have appeared as a fundamental method for controlling a large variety of cellular activities, such as growth, programmed cell death, and angiogenetic dynamics. Moreover, exosomes have been reported to play a central role in regulating innate and adaptive immune responses, contributing to antigen presentation in connection with major histocompatibility complex (MHC) molecules ,3.Several experimental findings recently confirmed exosome participation in different diseases such as autoimmune pathologies, neurodegenerative diseases such as Alzheimer’s and Parkinson’s, infective diseases such as tuberculosis and HIV, and cardiovascular disorders .Exosomes are involved in cancer development and diffusion and could be essential in provoking the phenomenon of chemoresistance. Evidence suggested that cell-derived EVs could mimic their parental cells, possessing the same pro-tumor and anti-tumor effects, and inherent tumor tropism. Therefore, cell-derived EVs can be a cell-free cancer treatment alternative .For this motive, numerous efforts have been performed to intervene on neoplasms modifying exosome functions, exploiting exosomes that have a cell-specific tropism, determined by the elements present on their external face, directing them to precise cells or tissues . It has The use of exosomes and their modulation for the treatment of solid neoplasms and hematological tumors is the subject of this review, which examines both in vitro and in vivo experiments and the still few clinical studies that have employed exosomes in the treatment of oncological diseases.Breast cancer (BC) is the most frequent form of tumor detected in the female sex, with 2.1 million cases every year. It is responsible for the most significant amount of cancer-correlated death in women, with an overall 15% death provoked by tumor annually .It has been reported that an augmented concentration of exosomes happens in the BC cells ,13. ExosBC cell-originated exosomes enclose several different cancer-exclusive nucleic acids and proteins, which are transferred and integrated by adjacent cells, such as mesenchymal stem cells (MSC). Consequently, MSC can be re-conditioned by alteration of altering their physiological trophic capacities into pro-tumoral functions. On the other hand, absorption of MSC-derived exosomes by tumor cells can modify the function of tumor cells, comprising BC cells. Thus, MSC-derived exosomes can transmit the input to block or to promote cancer proliferation, and the reciprocal transmission of exosomes between MSC and tumor cells modifies tumor cell behavior .Different approaches have been implemented to perform exosome-based treatment in BC subjects. The knowledge of exosome genesis has allowed to generate exosomes from other cell lines labeled with monoclonal antibodies to target BC cells . For insSimilarly, miRNA-106a-5p is augmented in triple-negative breast cancer (TNBC) cells and is positively associated with the cancer grade, suggesting a bad outcome for TNBC patients. MSCs can transfer miRNA-106a-5p into TNBC cells via exosomes. Several experiments demonstrated that exosomal(exo)-miRNA-106a-5p produced by MSCs facilitates cancer diffusion in TNBC cells. However, administration of lncRNA HAND2-AS1 under-expressed in TNBC cells can reduce the production of exo-miRNA-106a-5p from MSCs, suppressing TNBC development .In a different experiment, miRNA-126, which efficiently controls the activation of oncogenic genes and inhibits the signaling of PTEN/PI3K/AKT, has prevented the diffusion of BC .In addition to MSCs, macrophages have a role in the exosome-based treatment of BC. M2 macrophages are the most numerous cell types in the BC milieu and have a relevant effect on cancer diffusion. A study demonstrated that exosomes effectively transport miRNA-130 into macrophages, followed by an increase in M1 molecules and chemokines, such as TNF-α, IL-1β, Nos2, CD86, and Irf5 and a reduction in M2 mediators such as TGF-β, IL-10, CD206, Arginase, and Ym1. Moreover, the therapy with miRNA-loaded exosomes favors the phagocytosis capacity of macrophages. Resetting macrophages from M2 to M1 has been shown to decrease the growth and diffusion of 4T1 breast cancer cells .Using exosomes as transporters of molecules with therapeutic effects has been a further attempt for the therapy of BC. Biomimetic exosomes are generated by natural materials such as cell membranes from tumor cells, or other cells such as platelets, red blood cells, white blood cells, platelets, and might be used for anticancer drug delivery. These exosomes have long-lasting persistence, target-homing capacity, and biocompatibility . ExosomeSimilarly, a macrophage-originated exosomes-coated poly(lactic-co-glycolic acid) nanoplatform for treating TNBC employing doxorubicin was made . In thisFurthermore, the exosomes can be labeled with specific antibodies, thus obtaining a drug-antibody conjugate which determines a greater specificity and efficacy of the drugs. Trastuzumab emtansine (T-DM1) is an antibody–drug conjugate that carries a cytotoxic drug (DM1) to HER2-positive cancer. The transport of DM1(T-DM1)-originated trastuzumab-labeled exosomes to BC cells exhibited increased toxicity against cancer cells. It has been speculated that this effect is due to a stimulation of caspase-mediated programmed cell death in BC cells .Exosomes can also be charged with a series of different molecules such as carboplatin, aquaporin, and aspirin. Experiments were made with MSC-originated exosomes treated to obtain MSCCXCR4 + TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) transduced with CXCR4, the most frequently observed chemokine receptor in tumor cells. It turned out that exosomes-CXCR4 + TRAIL had a synergistic effect with carboplatin in a SCID mouse model MDA-MB-231Br, setting the stage for a new approach for the therapy of BC brain metastases .Non-cytotoxic molecules can also be employed to modify exosomes. Recent findings suggest that aspirin could increase BC subjects’ survival by 20% and significantly improve therapy outcomes through a COX-1-dependent effect and rapid alteration of epidermal growth factor and EGF receptor internalization . The antγ and IL-17, and the slightest concentrations of HIF-1 alpha, MMP-2, MMp-9, IL-4, FoxP3, and VEGF the IT+IP+TEX-treated group phenoxazine-5-one which results in decreased BC proliferation in vitro as well as in vivo phenoxazine-5-one, resulting in decreased BC proliferation in vitro as well as in vivo [An interesting cancer treatment procedure was proposed by Wang et al. employing gene-delivered enzyme prodrug therapy (GDEPT) in HER2 in vivo .Studies on BC-derived exosomes aiming at cell-to-cell communication in tumor advancement, diagnosis, and therapeutic technologies may assist in further obtaining exosome-based cellular control systems for BC treatment by eliminating and/or inactivating cancer-correlated exosomes, which augment tumor progression or employing exosome-based intracellular transport of functional molecules. A critical role will be played by analyzing exosomal miRNAs expression profiles and amounts closely correlated to BC extent, type, and prognosis. Deep comprehension of such relationships and the systematization of experimental results will give a new BC identification and management approach.Drug resistance, the main obstacle to BC therapy being correlated to a lousy outcome , is moduFurthermore, macrophage-originated exosomes armed with PTX, and doxorubicin can be employed to overwhelm the multidrug resistance in BC . The senLung cancer (LC) is the leading cause of tumor-related death worldwide, and non-small-cell lung cancer (NSCLC) stands for about 85% of all cases of LC .As in the case of BC, numerous experiments on the therapeutical use of exosomes have been performed for the LC. For instance, the inhibitory effect of miRNAs transported by exosomes was evaluated. Human cell-originated exosomes containing miRNA-497 efficiently inhibited cell proliferation and the production of genes such as VEGF, cyclin E1, yes-associated protein 1, and hepatoma-derived growth factor in A549 cells of NSCLC . RemarkaA similar effect with an antineoplastic action can target lymphatic vessels, which are essential constituents of both cancer and lung microenvironments. Once cancer has taken roots, nearby lymphatic endothelial cells (LECs) are stimulated and generate novel vessels under the effect of specific signals sent by cancer cells or the milieu. In a study, Yang et al. demonstrated that glypican-5 (GPC5), a component of heparan sulfate proteoglycans, augments the expression of CTDSP1 (miR-26b host gene) through the AhR-ARNT system, and such an increase causes a reduction in lung tumor cell proliferation. Furthermore, exosomes originating from GPC5-overexpressing lung cancer cells (GPC5-OE-originated exosomes) had an inhibitory action on LECs, reducing their generation and diffusion. The mechanism of action of miRNA-26b in LEC is related to the inhibition of the protein tyrosine kinase 2 (PTK2) 3′-UTR .Similarly, let-7a-5p delivered from macrophages to lung tumor cells inhibits lung cancer cell proliferation acting, via PI3Kg signaling system, on Bcl-2-like protein-1 (BCL2L1), a potent inhibitor of apoptosis. This finding was demonstrated in vitro on A549 lung cancer cells, and it has been observed that altered production of let-7a-5p modifies the survival of lung cancer patients. Moreover, altered expression of BCL2L1 considerably changes the generation of lung tumor markers such as vimentin, MYC, and EGFR .Xue et al. demonstrated that the combination of miRNA-34a and K-ras siRNA enclosed in lipid polymers positively affects a lung adenocarcinoma model .Moreover, the exosomes can be charged with drugs used to treat lung cancer. Antitumor effectiveness of airway-delivered exosomes armed with paclitaxel was reported in a model of murine Lewis lung carcinoma pulmonary metastases . Moreove+ cells and reduced the amounts of T-regulatory cells, macrophages, and tumor-infiltrating PD1+ T-cells [A further strategy of cancer treatment can be performed by promoting the anticancer immune response. Cortez et al. reported that exosomal transfer of miRNA-34a mimics (MRX34) into a lung adenocarcinoma experimental animal model increased the number of cancer-infiltrating CD8 T-cells .Always in this area, dendritic cells (DC) vaccine-based immune treatment has been applied as a therapeutic approach for tumor therapy. However, the anticancer action of DC vaccines performed on tumor cell lysates (TCLs) has given unsatisfactory results due to cancer antigens’ modest immunogenicity. Tumor-associated exosomes (TAEs) have been studied as an encouraging opportunity for DC vaccines. In a study, authors isolated TAEs from the supernatant of cancer cell culture medium and compared the action of TAEs with TCLs on DCs. The results proved that TAEs were more efficient than TCLs in stimulating DC, causing a more robust tumor-specific cytotoxic T lymphocyte response.γ-maturated DCs. It was reported that such exosomes cause stronger T cell stimulation versus DC-originated exosomes from immature DCs. Thirty-two percent of patients showed stability of their tumor for over 4 months, while only one patient presented grade-3 hepatotoxicity [Furthermore, TAEs decreased the presence of PD-L1 of DCs, thus provoking a decrease in T regulator cells in vitro. Finally, DC-TAE significantly reduced cancer proliferation and augmented survival in vivo . Based otoxicity .Then et al. performed a study to evaluate the capacity of cryopreserved umbilical cord blood mononuclear cell-derived DCs (cryo CBMDCs) and their exosomes to modify allogeneic T cell growth and to study toxicity against A549 lung tumor cells . They prMoreover, unconventional substances with anticancer potential can be inserted into exosomes. Employing bovine milk as a fount of exosomes, Munagala et al.  showed tCurcumin is another substance studied in anticancer treatment as it induces DNA hypomethylation, which epigenetically regulates genome stability . CurcumiLung tumor-derived exosomes transferring molecular information from LC cells to cells close to them or at distant sites may activate the tumor microenvironment and accelerate tumor diffusion. Exosomes seem to intervene in the regulation of numerous processes that affect neoplastic lung cells, such as angiogenesis, apoptosis, and the immune response. Furthermore, exosomal miRNAs might be believed as noninvasive markers for precocious diagnosis of LC. Finally, several promising modalities in the treatment of LC with loading microRNAs, drugs, protein, and siRNAs inside specific antigen-targeted exosomes have been proposed.Various exosome-associated substances can reduce resistance to drugs used in lung cancer, such as cisplatin and erlotinib. For instance, by operating as tumor suppressors, exosome-associated miRNA373, miRNA146a-5p, and miRNA512 are strongly correlated with reduced chemoresistance to cisplatin ,73. CAFsPRPS2) is reported as an oncogene in different tumors. PRPS2 increases cisplatin resistance of NSCLC cells enabling exosome-mediated macrophage M2 polarization in NSCLC tissues [Moreover, phosphoribosyl pyrophosphate synthetase 2  is among the more frequent tumors affecting about one million people every year. Its mortality percentage ranks fourth among cancer-related deaths .Managing miRNAs originating from exosomes is a possible therapeutic approach to CC. The aberrant increase in macrophages in CC tissues participates in its diffusion, and exosomal miRNA-183-5p has been reported as an oncogene. Zhang et al. studied the influence of exosomal miRNA-183-5p enhanced by M2-polarized tumor-associated macrophages (TAM) on CC cells . M2-TAM-Moreover, it is interesting that cancer cells and normal cells possess different miRNAs originating from exosomes, with different consequences. A study evaluated miRNAs in exosomes derived from human CCC SW620 cells and human normal colon epithelial cells NCM460 . Two groOther molecules can modify the activity of the non-coding genetic material, varying their pro or antineoplastic activity. For instance, Sevoflurane, an inhaled anesthetic frequently employed in clinical practice, has a remarkable effect on CC cell proliferation . CirculaTreatment founded on 5-fluorouracil (5-Fu) is the conventional line for the therapy of CC, but chemoresistance to 5-Fu is the main reason for tumor advancement in CC subjects.β1, an inducer of the Smad pathway, could partially reduce this effect. Thus, the Exo-GDF15-Smad axis might be a new target to increase sensitivity to 5-FU in colon cancer [Exosomes from 5-Fu-resistant CC cells seem to stimulate angiogenesis, and exosomal growth/differentiation factor 15 (GDF15) is a potent activator of the angiogenetic dynamics by blocking the Smad pathway. Transforming growth factor (TGF)-n cancer .Hepatocellular carcinoma (HCC) constitutes about 75% to 85% of primary liver tumors. Current data report that approximately 840,000 people experience HCC every year moreover, and about 780,000 people die from this form of tumor every year [Several types of exosomes seem to have a tumorigenic effect on HCC. For instance, Sphingosine kinase 2 (Sphk2) is a relevant controller regulator in exosome genesis. Employing Sphk2 siRNA-loaded nanoparticles can decrease miRNA-21 presence into exosomes, participating in reducing the HCC pro-tumoral activity of exosomes .Other data propose that MSC-originated exosomes could block HCC development, which was correlated with transporting cancer-suppressed ncRNAs ,86. ContLou et al. described that miRNA-122-transfected adipose mesenchymal stem cells (AMSCs) could store miRNA-122 into exosomes, and miRNA-122-loaded exosomes make HCC cells more susceptible to chemotherapeutic drugs by reducing metalloprotease domain 10, insulin-like growth factor 1 receptor, and cyclin G1 . Liang eGRP78), a well-known molecular chaperone in mammalian cells, is correlated with sorafenib chemoresistance but employing exosomes containing siRNA against siRNA GRP78 could inhibit sorafenib resistance in HCC [Moreover, it is possible to employ siRNA-armed exosomes to treat HCC. For example, glucose-regulated protein 78 , an alkaloid found in the root of the plant of cells .miRNA-142 and miRNA-223 can also be transported from macrophages to liver cells by exosomes to reduce the proliferation of HCC cells . ExosomaRecent experiments show that AD-MSC-originated exosomes can stimulate anti-HCC NK T cell responses in rat N1S1 cells (an orthotopic HCC model) . This an+ T lymphocytes and augmented the concentrations of IFN-gamma and interleukin-2, with reduced CD25+/Foxp3+ regulatory T cells and reduced concentrations of interleukin-10 and transforming growth factor-beta in the cancer microenvironment. The absence of effectiveness in CD8+ T cell-depleted mice suggests that T cells participate in DEXAFP-mediated anticancer activity [Alpha-fetoprotein (AFP)—expressing DC-originated exosomes (DEXs) produced a powerful antigen-specific immune response and determined a decreased HCC proliferation and augmented survival of animals with carcinogen-caused HCC tumors that exhibited antigenic heterogeneousness . Moreoveactivity . Howeveractivity .Chemoresistance sometimes makes ineffective the treatment with Sorafenib of HCC patients with advanced disease . It has miRNA-744 was reduced in exosomes originating from resistant HCC cells, and these exosomes could be absorbed by non-resistant HCC cells. The reduced concentration of miRNA-744 causes an increase in paired box 2 that favors HCC cell growth and reduces the chemosensitivity of non-resistant HCC cells .TGFβ has also been associated with chemoresistance as it decreases the sensitivity of HCC cells to sorafenib or doxorubicin and modifies the delivery of both extracellular vesicles and specific long non-coding RNA (lncRNA) within these vesicles. LincRNA-ROR (linc-ROR), a stress-responsive lncRNA, was highly increased in HCC cells. Incubation with HCC-originated EVs augments linc-ROR expression and decreases chemotherapy-caused cell death via the repression of p53 . These rLou et al. evaluated if MSC-originated exosomes could operate as transporters of miRNA-199a-3p to augment HCC chemosensitivity. In this study, miRNA-199a lentivirus infection and puromycin selection generated miRNA-199a-modified AMSCs (AMSC-199a). AMSC-Exo-199a appreciably reduced chemoresistance of HCC cells to doxorubicin in vitro by altering the mTOR signaling pathway. Moreover, its effect was significantly augmented by i.v. administration in vivo .HCC cells treated with exosomes and cisplatin display augmented sensitivity to cytotoxic T lymphocytes (CTLs), with prolonged survival of animals. Likely, after immunization with exosomes, FasL increases spleen lymphocytes’ binding to the Fas on target cells, inducing HCC cells apoptosis. This data suggest that exosomes can synergize with chemotherapy and remarkably augment their antitumoral effects.On the other hand, as reported above, exosomes can also augment chemoresistance in HCC. Exosomes from two aggressive HCC cell lines were able to provoke sorafenib resistance in vitro by stimulating the hepatocyte growth factor/c-Met/Akt pathway and reducing sorafenib-caused programmed cell death .Finally, Rab27B expression in 5Fu-resistant Bel7402 (Bel/5Fu) cells augments remarkably analogized drug-sensitive Bel7402 cells, and Bel/5Fu cells produced more exosomes under 5Fu stimulation. Moreover, exosomes produced by Bel/5Fu cells suggestively decrease after knocking down Rab27B, and the cellular levels of 5Fu augment, increasing its therapeutic action. The dispensation of drug efflux pump inhibitors and knockdown of Rab27B further extend the positive actions of 5Fu .Malignant melanoma is the most severe skin cancer, and its frequency is continually increasing, and with metastatic diffusion, subjects have a negative outcome .Inserting active molecules into exosomes could be a valid approach to treat melanoma. Some experiments demonstrated that MSC-originated exosomes could reduce melanoma diffusion via increased apoptosis or a cell cycle arrest with an augmentation of caspase3 cleavage and a decrease in Akt phosphorylation. Other experiments suggest that exosomes interfere with angiogenetic processes reprogramming melanoma cells and reducing VEGF expression.In a well-designed study, mesenchymal stem cells presenting TRAIL/green fluorescent proteins  were geTripterygium wilfordii Hook F, were evaluated for the treatment of melanoma [In a different study, TRAIL-modified exosomes charging triptolide (TPL), the principal active and toxic component of melanoma . TRAIL/Tmelanoma .Numerous studies have used various engineered liposomes to treat melanoma ,111. Sim+ T cells and an improved antitumor immune response [However, the most innovative therapeutic attempt involves the activation of the Stimulator of Interferon Genes (STING) system associated with the innate immune response. Stimulation of the cytosolic DNA sensor STING in antigen-presenting cells (APC) causes a response to type I interferon. However, STING agonists (STINGa) have negative pharmacological characteristics, such as rapid clearance and inadequate transfer to the cytosol. McAndrews et al. used exosomes loaded with STING’s GMP-AMP cyclic agonist (iExoSTINGa) to specifically target the STING pathway in APCs with greater efficacy than STINGa alone in inhibiting B16F10 cancer proliferation. Furthermore, iExoSTINGa showed greater uptake of STINGa in dendritic cells than STINGa alone, with a significant increase in stimulated CD8response .Finally, tumor vaccination has been limited by the complex recognition of specific cancer antigens and their transport to APC. The exosome-founded cancer antigens-adjuvant co-transport technique employing genetically modified cancer cell-originated exosomes, including cancer antigens and immunostimulatory CpG DNA, was used in a murine melanoma B16BL6 . Murine Epithelial ovarian cancer (EOC) is the leading cause of gynecological-correlated deaths and the fifth reason for tumor mortality in women .Numerous studies have demonstrated the therapeutic efficacy of exosome-based therapy in ovarian cancer. For instance, macrophage-originated exosomes bearing TNF-like weak inducer of programmed cell deaths (TWEAK) reduce the motility and diffusion of EOC cells. Their action is due to the increased production of miRNA-7 with the reduction of EGFR/Akt/ERK1/2 pathway stimulation, proposing that exosomal miRNA-7 from TWEAK-activated macrophages may have encouraging therapeutic perspectives ,117.IRGD exosomes, generated through transfecting plasmid with cancer-targeting peptide IRGD to exosomes, were reported to interconnect with ovarian cancer cell NuTu-19 via membrane fusion specifically. IRGD exosomes armed with adriamycin (Dox) were administered to animals with ovarian tumors causing a reduction in the tumor volume . SimilarT. wilfordii Hook F., which has numerous anticancer, and immunomodulatory effects, the clinical use of which is limited due to severe side effects. It has been demonstrated that TP-enclosed exosomes stimulate programmed cell death, modify the cancer milieu by repressing M2 cancer-associated macrophages, and augment anticancer immunity. Unlike free TP, they remarkably increased the anti-tumor effects, with a reduction in side effects [As reported above, Triptolide (TP) is a molecule that has been isolated from the herbal medicine  effects .Interfering with miRNAs contained in exosomes has been demonstrated as a promising way to treat EOC. MiRNA-101 mimics are possible therapeutic tools for EOC therapy as it inhibits the production of brain-derived neurotrophic factor by acting on 30-UTR . DiffereSince omento fibroblasts are a source of exosomes ,123, KobFinally, exosome mimetics facilitate the transport of other active substances. Immune-derived exosome mimetics (IDEM) resulted in a productive attempt to treat ovarian cancer cells . IDEM weFinally, exosomes can transport substances implicated in antigen presentation, such as MHCI, HSP, and tumor-associated antigens, suggesting the possibility of an EOC immune treatment. For example, Andre et al. demonstrated that exosomes taken from malignant ascites represent a source of cancer antigens that could be transported to DCs, favoring the proliferation of cancer-specific cytotoxic T lymphocytes, provoking an anticancer response . A phaseThe fast dissemination of EOC causes several treatment challenges. Exosomes can stimulate cell angiogenesis, immunosuppression, division, and tissue invasion, crucial for EOC progression. Moreover, exosome protein signatures that are derived from EOC have been recognized. Clinically, these data may allow appropriate modifications in treatment before the onset of diffuse disease evolutions. Evaluation of the differential expression of metastatic genes derived from circulating exosomes might represent an easy screening tool for EOC detection and longitudinal monitoring of changes associated with metastatic spread. Finally, exosomes are also attractive candidates for drug delivery. At the same time, studies suggested that miRNA replacement therapy using exosomes derived from non-malignant cells may be a promising tool for EOC treatment.OC has one of the highest rates of chemoresistance-related relapse: over 50% of all OCs in 5 years. Exosomes have a relevant effect in inducing this phenomenon as exo-miRNAs can control the gene activation of target cells and can favor chemoresistance in OC cells.κB block decreased the production of miRNA-429 and restored the sensitivity of EOC cells. Resistant cells pretreated with an NF-κB inhibitor or miRNA-429 antagomir displayed sensitivity to drugs such as cisplatin and showed reduced cell growth [Li et al. demonstrated higher concentrations of miRNA-429 in multidrug-resistant SKOV3 cells and their exosomes (SKOV3-EXO) than insensitive A2780 cells and their exosomes . Exo-miRl growth .Similarly, serum exosomal concentrations of miRNA-214-3p were remarkably augmented in platinum-resistant EOC cells. Transfecting the miRNA-214-3p inhibitor in EOC cells, cell growth was reduced, whereas programmed cell death was augmented. This effect appears to be due to altered mitochondrial functions caused by disproportionate ROS generation .miRNA-1246 production was also remarkably significant in PTX-resistant OC exosomes than insensitive counterparts, and experimentation demonstrated that the Cav1 gene, which is the target of miRNA-1246, is implicated in exosomal transport . AugmentA different possibility to induce cisplatin resistance was identified by evaluating the genomic DNA methylation pattern. DNA methyltransferase 1 (DNMT1) is responsible for genome-wide methylation. DNMT1 transcripts were incredibly augmented in exosomes from ovarian cells, and in vivo employment of DNMT1-containing exosomes increased chemoresistance and xenograft progression and diminished overall survival. However, therapy with exosome inhibitor GW4869 reestablished sensitivity in resistant cells .Finally, hypoxia, an essential element favoring the diffusion and aggressivity of OC, increases chemoresistance . Rab proMoreover, exosomes from ascites of OC patients under hypoxia transported more powerful oncogenes. Hypoxic OC cells originated exosomes efficiently modify the fallopian tube epithelial cells to be pro-oncogenic in animal models. Finally, cisplatin efflux through exosomes was significantly augmented in OC cells under a hypoxic situation. Preventing exosome liberation by amiloride or STAT3 inhibitors caused a marked increase in programmed cell death, decreased colony formation, and cisplatin-treated OC growth .Pancreatic cancer (PC) is digestive cancer with the worst outcome. The 5-year overall survival is less than 5% .As in the case of the solid neoplasms previously described, it is also possible to transfer substances with therapeutic activity by exosomes in the case of PC. In a study, gemcitabine (GEM) was stored into autologous exosomes to generate ExoGEM to treat PC. Exosomes favored cellular absorption of GEM and determined augmented cytotoxic activity of GEM. In experimental animal models, exoGEM treatment reduced cell proliferation, with prolonged survival and insignificant injury to normal tissues. Furthermore, PC in animals treated with ExoGEM regressed without relapse . SimilarSeveral other reports proved exosomes’ capacity to transport and release different molecules that target cancer cells or genes implicated in PC onset and progression. For instance, it was reported that exosomes could transport Curcumin in PC cells with in vitro cytotoxicity . FurtherThe combined use of drugs such as GEM, all-trans retinoic acid (ATRA), and sunitinib  with vaccines including DCs stocked with PC-originated exosomes proficiently blocked the diffusion of metastases and augmented animals’ survival .Targeting macrophages is an encouraging method for PC treatment. Su et al. demonstrated that exosomes originating from Panc-1 cells induced a change in M1 macrophages to assume an M2 phenotype. However, this could be reversed by administering the M2 macrophages exosomes from Panc-1 cells that have been transfected with miRNA-155 and miRNA-125b2. In this case, the M2 cells reverted to an antitumor M1 phenotype .A therapeutic attempt was to use a biomimetic tactic based on membrane fusion. Deng et al. generated a platform by combining CLT (Celastrol)-armed PEGylated lipids with the DC2.4 cell membrane (M-LIP-CLT) applied for the treatment of Kras-mutant PC with exceptional anti-tumor efficacy . This hyCancer-originated re-assembled exosomes (R-Exo) were employed as a drug transporter and an immunostimulatory mediator. A chlorin e6 photosensitizer was stored into cancer-originated exosomes during exosomal re-assembly. Chlorin e6-loaded R-Exo (Ce6-R-Exo) can produce ROS in cancer cells proficiently under laser irradiation. Moreover, Ce6-R-Exo augmented the production of cytokines by immune cells, which suggests that these specific exosomes can be employed for immunotherapy .A different therapeutic attempt is to modify miRNAs enclosed in exosomes. Amongst these miRNAs, miRNA-124 was particularly interesting in PC patients. Some reports have demonstrated that miRNA-124 production diminishes in PC subjects, and K-Ras has been recognized as a direct target of miRNA-124. Moreover, enhancer of zeste 2 polycomb repressive complex 2 subunit is a histone methyltransferase that regulates the methylation of H3K27me3 in PC and has been reported to be a downstream gene of K-Ras. A study evaluated the anticancer effects of miRNA-124 delivered by BM-MSC-derived exosomes. To assess the effects of miRNA-124 against PC, the miRNA-124-3p mimic and pcDNA3.1-EZH2 were transferred into AsPC-1 and PANC1 cells. The miRNA-124 mimic transfection remarkably augmented the intracellular miRNA-124 concentrations, while the transfection of pcDNA3.1-EZH2 significantly augmented the generation of EZH2. Augmented levels of miRNA-124 reduced cell survival and increased programmed cell death, while the increase in EZH2 inverted this effect. Moreover, augmented levels of miRNA-124 decreased the diffusion and EMT of PC cells .miRNA-34a inhibits several families of proteins, which are implicated in cell proliferation, and apoptosis. In addition to targeting Bcl-2, an apoptotic controller, miRNA-34a, reduces the production of Yin and Yang 1 (YY1) protein and Notch1/2 . ExosomemiRNA-126-3p also blocked PC proliferation and diffusion originating from BMSCs exosomes by reducing ADAM9 .However, other non-coding genetic material could be a proper therapeutic target besides miRNAs. Several data have demonstrated that circRNAs were abnormally present in PC cells and contributed to the onset and diffusion of PC . SCL/TALP21-activated kinase 4 (PAK4), a component of the PAK group of serine/threonine kinases which operate as mediators of numerous small GTPases, has oncogenic activity when augmented, stimulating cell growth and diffusion. PAK4 is overexpressed in PC cells, and increased PAK4 expression is parallel with the expanded production of c-Met and the p85α subunit of PI3K. Thus, PAK4 might be a therapeutic target in PC, as demonstrated by administering Exo-mediated RNAi . Intra-tOther experiments have confirmed the possibility of blocking the expression of specific genes to treat PC cells. Kamerkar et al. modified exosomes to transport siRNA or shRNA aiming KRAS in PC cells, which efficaciously blocked cancer proliferation in experimental animal models and augmented the overall survival , while MCancer-associated fibroblasts (CAFs) regulate chemoresistance by transporting exosomal miRNAs to tumor cells. It has been demonstrated that CAFs were intrinsically resistant to gemcitabine (GEM), and the exosomes originating from CAFs participated in the onset of GEM resistance. MiRNA-106b concentration was augmented in CAFs exosomes after GEM treatment, and pretreatment miRNA-106b inhibitor favored a reduction in chemoresistance of PC cells to GEM .We report in Leukemia-originated exosomes transport molecules that increase cellular growth and augment programmed cell death of leukemic cells.Acute myeloid leukemia (AML) is a hematologic neoplasm distinguished by a high degree of alteration of differentiation and by abnormal growth of myeloid progenitor cells.The possibility to use exosomes for leukemia treatment has been proved by several experiments . DibavarInterestingly, Peng et al. detected that miRNA-34c-5p, a miRNA controlling the senescence process, was remarkably decreased in AML stem cells compared to normal hematopoietic stem cells . This loThus, in-depth studies have examined the role of exosomes produced by AML blasts and how the bone marrow microenvironment changes in favor of leukemia progression and survival to identify the mechanisms of treatment failure. Findings demonstrated that malignant cells could modify the behavior of adjacent cells, and by secreting exosomes containing immune-inhibiting cytokines, AML cells render inoperative the immune system against leukemic cells, guaranteeing their survival. Thus, leukemia-derived exosomes support clonal cell growth while suppressing normal hematopoiesis; therefore, inhibiting the generation of these exosomes as well as their reprogramming seems to be an interesting approach in leukemia treatment.γ, lymphocyte function-associated antigen (LFA-1), DNAX accessory molecule-1 (DNAM1), and programmed cell death protein (PD-1) [Finally, exosome-based therapy has been used to stimulate an immune response against AML. Stimulated NK cells generate significant quantities of exosomes that contain important cytotoxic molecules, including IFN-n (PD-1) . Vaccinen (PD-1) . In thisn (PD-1) . Unexpecn (PD-1) . TherefoThe effect of exosomes inducing resistance to various chemotherapeutic drugs such as doxorubicin and etoposide is decisive. For instance, U937 cells augment their resistance against the PEGylated liposomal doxorubicin (PLD) via the exosome-related discharge of the PLD. Blocking exosome delivery could stop PLD emission and raise the susceptibility of U937 cells to the toxic actions of PLD. U937 cells were administered with PLD with or without the dispensation of the exosome discharge blocking agent, GW4869. Inhibitor administration augmented cell death. Remarkably, the administration of GW4896 and 0.5 μM PLD induced the equivalent cytotoxic action as that of the 1 μM PLD .In a further study, it has been reported that exosomes isolated from AMLs stimulate IL-8 production in HS-5 BMSCs, which causes etoposide resistance in AML cells. Blocking exosomes or IL-8 can revert the chemoresistance, with augmented etoposide-induced apoptosis of AML cells .Numerous evidence has proved that exosome-originated miRNA-181a affects central nervous system alteration in pediatric acute lymphoblastic leukemia (PALL), and the use of an miRNA-181a inhibitor may produce beneficial effects in PALL . BlockinAnti-leukemic immune responses can also be obtained for ALL by administration of leukemia-originated exosomes. The shRNA inhibition of TGF-β1 in ALL cell lines efficaciously decreased the TGF-β1 concentration in exosomes originated from leukemic cells (LEX). When LEXTGF-β1si were absorbed by DCs, they were able to stimulate DC activities by augmenting the presence of MHC class II molecules. Moreover, they caused the production of TNF alpha and IL-12p70 and augmented CD4+ T-cell growth and Th1 cytokine production. Finally, they induced a powerful T lymphocyte and NK cell cytotoxic response. In experimental animal models, administration of LEXTGF-β1si provoked an inhibition of leukemia cell proliferation and prolonged survival .Exosome-based immunotherapies are safe and effective. For instance, CAR-T cell treatment is burdened with numerous side effects, such as cytokine storms. Haque et al. generated exosomes presenting CD19 CAR to treat CD19-positive B-cell neoplasms. This approach decreased the risk of excessive cytokine discharge and was associated with cellular toxicity and augmented programmed cell death genes in CD19 leukemia B-cells without causing apoptosis in CD19-negative cells .Relapsed leukemia is generally due to the therapy failure due to chemoresistance. Vincristine and prednisone are drugs employed for the ALL therapy, as they cause programmed cell death in first-line leukemia. However, these drugs do not provoke apoptosis in relapsed leukemia. This is probably due to the inability to determine suppression of cellular and exosomal miR-181a expression. These findings propose a possible effect of an inhibitor on exosome-derived miRNA-181a in the treatment of relapsed ALL .Chronic myeloid leukemia (CML) is a malignancy distinguished by a reciprocal translocation between the long arms of chromosomes 9 (ch9) and 22 (ch22), which determines the production of the Philadelphia chromosome. Even though the insertion of tyrosine kinase inhibitors (TKIs) transformed treatment and prognosis in CML patients, the use of new therapeutic approaches could further improve the natural history of this disease.In a study, a venetoclax-armed immunoliposome (IL-VX) was designed and showed a more remarkable ability to induce CML programmed cell death than free venetoclax . AnotherSeveral other substances might be used to arm exosomes against CML cells. Curcumin has been reported to display antitumor activities in many tumors . The addIt was also reported that curcumin exosomes reduce Ras homolog gene family member B (RhoB) production and negatively control endothelial cells diffusion. Adding CML exosomes to HUVECs provokes an augment in VCAM1 and IL-8 concentrations, but curcumin-loaded exosomes inverted these results, reducing their angiogenic effects. This antiangiogenic property was verified with in vitro and in vivo studies. Quantitative analyses of peptides of curcumin exosomes demonstrated that curcumin addition modifies their molecular characteristics. Curcumin stimulates the discharge of exosomes depleted of pro-angiogenic factors and enriched in proteins with antiangiogenic functions. Among these factors, Myristoylated alanine-rich C-kinase substrate (MARCKS) seems to play an essential role since it was a target of the miRNA-21 mentioned above. Thus, curcumin reduces the exosome’s capacity to stimulate the angiogenic phenotype and regulate the endothelial barrier structure .β1, enhanced in LAMA84-originated exosomes. Raimondo et al. assessed the autocrine effects of exosomal-TGFbeta1 on leukemic cells employing a TGF-β1 receptor inhibitor or a neutralizing antibody. They demonstrated that the exosome augmented cell growth, and the generation of an antiapoptotic phenotype can be avoided by inhibiting the TGF-β1 system [Other pathways could also be involved in exosome-intermediated treatment, such as the transforming growth factor (TGF)-1 system .Finally, Zhang et al. reported that BM MSC-Exo could block the growth of CML cells in vitro through miRNA-15a and induce apoptosis. These results were not achieved in BALB/c nu/nu mice. BMMSC-Exo augmented CML occurrence and stimulated tumor diffusion in vivo. It was reported that the production of the antiapoptotic protein Bcl-2 increased, while the caspase3 generation reduced . FurtherImatinib resistance is the greatest obstacle for the therapy of CML, and recently there was the observation that exosomes can affect drug resistance. It was demonstrated that hUC-MSC-Exo alone had no action on cell survival or programmed cell death of K562 951 cells. However, hUC-MSC-Exo promoted IM-induced cell viability inhibition and apoptosis. Moreover, hUC-MSC-Exo enhanced the increased Bax expression and the decreased Bcl-2 expression that IM induced. Interestingly, the antitumoral actions of hUC-MSC-Exo on K562 cells could be blocked by treatment with caspase inhibitor Z-VAD-FMK .In a different study, authors reported that miRNA-328 remarkably was reduced during the onset of imatinib resistance . MiRNA-3Lymphomas are lymphoid malignancies that originate from lymph glands or extra-nodal lymphoid tissue .+/Gr–1+ cells, induces an increase in programmed cell death, and has anti-inflammatory activity [Several substances can be inserted into exosomes for therapeutic purposes against lymphoproliferative diseases. Curcumin stored in lymphoma cells-originated exosomes target CD11bactivity .Cephalotoxus fortunei with an anticancer activity that operates synergistically with different drugs in non-Hodgkin lymphoma (NHL) via NOXA and MCL-1-dependent systems [Omacetaxine, previously identified as homoharringtonine (HHT), is a natural alkaloid originating from  systems . HHT int systems . A study systems .Koch et al. reported that treating diffuse large B-cell lymphoma (DLBCL) cell lines with a non-steroidal anti-inflammatory drug such as indomethacin leads to reduced exosomes discharge and inhibited lymphoma development. Moreover, they proved that a reduced exosome discharge causes an augmented efficacy of drugs such as anthracyclines, both in vitro and in vivo . A diffeA further attempt was to cause programmed cell death of lymphoma cells employing TRAIL-mediated apoptosis. Numerous molecules affecting this system have been identified, comprising TRAIL receptor agonists and recombinant soluble TRAIL. However, no substantial antitumor effects could be demonstrated in tumor patients. A novel possibility to transfer and discharge TRAIL could be to insert it within exosomes produced by TRAIL-expressing cells. Rivoltini et al. reported the capacity of TRAIL-loaded exosomes to move molecules able to reduce cell proliferation and stimulate programmed cell death in lymphoma cells . IntratuThe inhibition of numerous genetic pathways induced by modifying the activity of the exosomes could constitute a practical therapeutic possibility. Lunavat et al. generated exosome-like nanoparticles containing siRNA and demonstrated that inhibiting c-Myc effectively stimulated poly (ADP-ribose)polymerase-dependent apoptotic systems in l820 lymphoma cells . MoreoveSynthetic lipid vesicles loaded with active Apo2 ligand/TRAIL were evaluated on lymphoma cell lines with relevant pro-apoptotic action of cancer cells without effects on normal cells both in vitro and in vivo, with little toxicity in vivo .However, the possibility to manipulate exosomes to restore anti-lymphoma immunity was also confirmed in numerous other models of lymphoma. An exosome-DC vaccine was constructed to reestablish immune surveillance in lymphoma. Unlike what was described when DLBCL-originated exosomes were incubated with T-cells and caused their inhibition by producing different immunosuppressive substances , DLBCL-dThe capacity of exosomes to bind to particular receptors on both lymphoma cells and microenvironment cells via membrane molecules renders them an attractive instrument to transport exogenous cytotoxic and inhibitory molecules for therapeutic intents. Engineered exosomes are potent tools to be utilized against B-cell tumors. As stated above, it is clear that one of the several vantages is the possibility to join this approach with other strategies, such as traditional chemotherapy and those intending at rebooting the host immune system. These approaches have the potential to reduce tumor growth and diffusion, thus decreasing any off-target side effects.Multiple myeloma (MM) is classified by the clonal growth of neoplastic plasma cells and the production of monoclonal immunoglobulin in the BM. MM is still judged as an incurable malignancy ,196.MM is a disease with a highly destructive action on the BM. The delivery and discharge of exosomes MM plasma cells considerably modify the BM milieu, stimulating plasma cell proliferation and the onset of lytic lesions. This changed microenvironment establishes a particular place, a niche, which is superlatively appropriate for maintaining its growing elements and establishing a reduced immune response and chemoresistance .Several reports have evaluated the possibility to modify exosome production to target MM plasma cells. In animal MM experimental models, sphingomyelinase inhibitor GW4869 inhibited exosome discharge, avoiding the onset of exosome-mediated lytic lesions and augmenting cortical bone volume. GW4869 also powerfully operated synergistically with bortezomib to provoke anti-myeloma effects, proposing that modifying exosome transport and delivery can influence MM growth and viability. However, ceramide C6 (C6-cer), an exogenous ceramide, augmented MM exosome production but blocked cell growth and caused programmed cell death .Different molecules could help modify the generation and activities of exosomes in MM. For example, a noteworthy molecule is a protein called heparanase, supplied through the production of exosomes. Heparanase, produced both by MM or host cells, reaches the BM milieu and controls the activities of adjacent cells by stimulating the production of exosomes. It modifies exosome contents inducing the production of cytokines correlated to the onset of MM or the generation of blood vessels, such as VEGF, syndecan-1, and hepatocyte growth factor ,200. RepSeveral agents can inhibit heparinase, such as modified heparin or heparin mimics, that are presently valued in clinical trials. Purushothaman et al. demonstrated that heparan sulfate exerts a relevant effect on exosome-cell communication, encapsulating fibronectin on exosomes and operating as a receptor for fibronectin. This effect can stimulate pERK and p38 pathways or MMP-9 and Dickkopf-1 involved in MM advancement . The mosThe effects of other inhibitors were also evaluated. However, although a decrease in exosomes absorption was demonstrated in BMSCs after administration of molecules such as inhibitors of membrane fusion, endocytosis, or macropinocytosis, these compounds negatively modified the survival of BMSCs. Dynasore and heparin did not alter BMSC survival, while substances such as amiloride and omeprazole remarkably reduced BMSC survival. Moreover, they seemed to act via the inhibition of STAT1, STAT3, and ERK1/2 phosphorylation in the presence of RPMI8226 or H929 exosomes .The study of exosome activity after treatment could open new, unexpected fields of knowledge in MM . Many drDifferent mechanisms, such as an extra activity of immune effectors, determined by a modification of the movement of the exosomes, justify the therapeutic action of other substances. A study suggested that small dosages of doxorubicin and melphalan cause cell senescence, augmenting IL15/IL15RA complex production in MM cells and their exosomes, stimulating NK cell function, and growth . Thus, c+/Th1, CD8+/CTL, and NK-mediated anti-MM immune response. Moreover, membrane-bound HSP70 operated both as a damage signal and an antigenic peptide chaperone that stimulated DCs, representing an essential adjuvant for exosome-based antitumor vaccine [Finally, MM-originated exosomes as a source of MM antigens for vaccines have also been studied. Xie et al. demonstrated that HSP70-modified MM cell-originated exosomes induced DCs development and triggered effectual CD4 vaccine .A modulation of exosome activity could also be useful in preventing or treating numerous complications of MM. More than 50% of MM subjects present a heart injury such as heart insufficiency or cardiomyopathy provoked by amyloidosis or anemia. In addition, some treatments used for MM can affect cardiac function through specific circRNAs . For insExosomes could modify the resistance to MM treatment. Fact et al. reported an alteration in the sphingolipid metabolism, increasing ceramides and acid sphingomyelinase (ASM) and decreasing sphingomyelin . MoreoveAs reported above, heparanase (HPSE) is augmented in MM cells and correlates to MM cell proliferation and bortezomib (BTZ) resistance. Rodrigues-Junior et al. assessed miRNAs and HPSE presence in MM lines (U266 and RPMI-8226) , and synIn conclusion, exosomes have been involved in MM-correlated processes comprising angiogenesis, osteolysis, immune suppression, and drug resistance. Pursuing exosome production and secretion could, therefore potentially inhibit these different processes.In recent years, a wide variety of drug transporting platforms, such as nanoparticles, have been implemented. Still, they present several inconveniencies, such as their xenobiotic origin, which can provoke unwanted immune reactions and unexpected toxicities . On the Exosomes have several features that make them appealing for tumor treatment. For instance, they can elude blood clearance by the immune system , while tIn the near future, a fruitful field of study could be constituted by the analysis of the role played by exosomes in long-distance cell–cell communication, maybe from one organ to another. Tunneling nanotubes (TNTs) are membrane-enclosed tubular connections between cells that carry a large number of cellular cargoes, such as exosomes, non-coding RNAs, and mitochondria, and they have been recognized as the principal participants in tumoral cell communication. TNTs have been reported in several cancers in in vitro, ex vivo, and in vivo models promoting the onset and progression of tumors. Cancer cells employ TNT-like channels to transport information between themselves or with the tumoral milieu. As a result, tumor cells accomplish novel capabilities, such as the augmented capacity of metastasis, angiogenic capacity, and chemoresistance, elevating tumor severity .However, despite all these favorable characteristics, some inadequacies slow their clinical employment as a delivery system. The main problem is the difficulty of a large-scale preparation: the generation of subject-originated exosomes is expensive, time consuming, and challenging. Moreover, the reproducibility represents a different difficulty, as experimental data suggest that three diverse formulations of exosomes from MSC only shared 20% of their proteome.An encouraging option for exosome-founded cancer treatments is manufacturing exosome mimetics, which could allow the synthesis of exosomes appropriate for clinical employment.A different source of exosomes could be plants. Plant exosomes show similar characteristics to those of mammalian exosomes. Plant exosomes have been defined as “exosome-like” as their appearance and size are comparable to mammalians. Numerous experiments have demonstrated that edible plant-originated exosomes can aggregate in mammalian cells, while plant microRNAs might operate as controllers of biological functions in mammals. In particular, plant-derived exosomes have antitumor activity, as in the case of Moringa oleifera seed exosomes  or CitruThe ability of exosomes to augment the radiation resistance of cancer cells opens exciting perspectives for their use in tumor treatment ,222. In In conclusion, exosomes are essential mediators and regulators of cellular communication. However, a complete full comprehension of the interchange between the cancer milieu and the exosome is necessary to apply them in clinical practice successfully. Identifying the exosomes’ contents is not enough to plan an exosome-associated cancer treatment but comprehending the communication patterns and forms of communication might be the key.