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Background: Castleman's disease is a rare and benign lymphoproliferative disorder which can be unicentric (UCD) or multicentric (MCD). UCD usually involves a single lymph node or less frequently a group of lymph nodes. The most common sites of nodal UCD presentation are the mediastinum, neck, abdomen and retroperitoneum. Rarely extranodal involvement has been reported. The intramuscular location is very unusual with only about 10 cases described in medical literature so far., Case Report: We present a case of atypical localization of Castleman's disease occurring in the right gluteal area in a 40-years-old female patient. The patient was asymptomatic and clinical examination was unremarkable except for a right gluteal palpable mass. The CT scanner-guided needle core biopsy was inconclusive. A surgical excision was then performed that revealed a hyaline-vascular type of Castleman's disease. The patient has an uneventful post-operative course., Conclusion: The present case is instructive in the work-up of primary soft tissue tumors, for which Castleman's disease is extremely rare and not considered in the differential diagnosis of clinicians. Pathologists must be aware of its existence so that it can be evoked in the presence of a lymphoid population on histological examination., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Background and Aims: Confocal endomicroscopy is a technique allowing the in vivo assessment of the superficial layers of the mucosa. Preliminary studies have already suggested its added value in the assessment of endoscopic remission in inflammatory bowel disease. However, most of these studies were performed on patients still having incomplete mucosal healing. Our aim was to disclose persisting endomicroscopic anomalies in patients with full endoscopic remission and to compare them between vedolizumab- and anti-tumor necrosis factor-treated patients., Methods: We screened patients with Crohn's disease (CD) or ulcerative colitis (UC) treated for more than 6 months with biologic therapy, and being in steroid-free clinical and biological remission. White light endoscopy and probe-based confocal laser endomicroscopy (pCLE) analysis were performed in the ileum, right colon, transverse colon, left colon, and rectum. Full endoscopic remission was defined by a Mayo endoscopic score of 0 in UC and no remaining ulcer or erosion in CD. Patients were prospectively followed up and clinical relapses were recorded., Results: Seventy-two CD and UC patients treated by biologic therapy and in clinical and biological remission were screened. A total of 37 were also in full endoscopic remission and were included in our study; 183 intestinal segments were analyzed. We found residual pCLE anomalies in most of the patients. These anomalies were not significantly associated with any demographic or clinical characteristic including the treatment received, nor were they associated with histological parameters, levels of C-reactive protein or fecal calprotectin. Among the 37 patients, 7 (18.9%) relapsed over a median follow-up of 33.7 months. The risk of relapse was not associated with any clinical, biological, histologic, or pCLE feature at baseline., Conclusion: Despite endoscopic, biological, and even histological remission, we found a high prevalence of endomicroscopic abnormalities, which were not different between anti-tumor necrosis factor- and vedolizumab-treated patients. The clinical significance of these anomalies remains to be clarified., (© The Author(s) 2023. Published by Oxford University Press on behalf of Crohn’s & Colitis Foundation. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The data on constrictive pericarditis following heart transplantation are scarce. Herein, the authors present 2 patients who developed a constrictive pericarditis 19, and 55 months after heart transplantation. They underwent several diagnostic procedures and successfully recovered after a radical pericardiectomy. In addition, the authors review the literature and report the incidence, aetiology, diagnostic features, and management of this rare and challenging condition.

Background: The advancing evolution toward a Th2 immune environment confers a progressive immunosuppression in patients with longstanding cutaneous T-cell lymphoma (CTCL). The conjunction of the disease-related immunosuppression as well as the immunosuppressive character of some CTCL treatments increase the risk of infectious and neoplastic diseases, sometimes with fatal outcomes., Objectives: The aim of the study was to prospectively study the causes of death in a cohort of CTCL patients, in a tertiary university skin cancer center., Methods: All CTCL patients who died between 2008 and 2020 were included. The cause of the death was classified as directly or indirectly related or unrelated to CTCL., Results: Over the study period, 31 (13F/18m) patients with CTCL died (mean age: 75.2 years), mean delay between diagnosis and death: 3.2 years (min: 1, max: 12 years), 58.1% of death causes were classified as indirect (infection), 12.9% directly related (blastic transformation), 22.5% unrelated, and 6.5% of unknown cause. 51.6% of mycosis fungoides (MF) patients who died had early-stage disease (1A-2A) or were on remission. 45.2% of dead patients had advanced-stage MF (2B-4B). Mean CRP level is increased in patients who died from infection whereas LDH level increased in patients with blastosis. A tertiary center is expected to manage of a higher proportion of CTCL patients with advanced-stage disease., Conclusions: As infection represented more than 50% of the causes of death in CTCL patients, particular attention should be given to preventive measures such as anti-infective vaccination. Regular surveillance of CRP and LDH levels could be helpful for follow-up of MF patients, respectively, with regards to infection and blastosis., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Background: : Hereditary leiomyomatosis (HL) is an autosomal dominant condition due to a variety of fumarate hydratase (FH) mutations in which individuals tend to develop cutaneous leiomyomas, multiple uterine leiomyomas and are at risk for developing aggressive papillary renal cell carcinoma., Case Presentation: : A 26-year-old man with a past history of acute lymphoblastic leukemia (T-ALL) presented with numerous painful light brown papules and nodules spread all over his body except for the head, appearing since infancy. Similar lesions were present in his mother's family. A cutaneous biopsy revealed a cutaneous leiomyoma. His mother died from metastatic uterine neoplasia and his sister suffered from leiomyoma of the uterus. No renal cancer was reported in his family. A heterozygous pathogenic variant was detected in the FH gene., Conclusion: : To our knowledge, this is the first case possibly linking HL and T-ALL through FH deficiency.

Introduction: Mycosis fungoides (MF) is the most frequent subtype of primary cutaneous T cell lymphomas (pCTCL). The diagnosis may be particularly difficult in the early stages as well as in atypical and rare clinical presentations. Furthermore, MF may simulate a large variety of common dermatologic disorders and patterns, both histopathologically and clinically., Methods: A literature search was performed to provide a comprehensive update on the rare and atypical MF manifestations as well as the dermatoses and dermatological patterns that could be imitated by MF., Results: A total of 114 publications were found describing a series of different dermatoses and dermatological patterns mimicked by MF, as well as some particular localizations of MF lesions and dermatoses that occur in preexisting MF lesions., Conclusions: The number of dermatoses that can be imitated by MF is ever-increasing. Patients with common dermatologic conditions that prove to be treatment refractory should be biopsied without delay, and sequentially as necessary, to prevent delay in diagnosis and progression of disease. Clinicopathologic correlation is the best way of diagnosis., (© 2021. The Author(s).)

A drug-induced sarcoidosis-like reaction is a systemic granulomatous reaction indistinguishable from sarcoidosis and occurring in temporal relationship with a drug initiation. In this article, we report a patient who developed lung and liver granulomatous lesions following tocilizumab initiation for a giant cell arteritis. Infectious, toxic, neoplastic and inflammatory differential diagnoses were ruled out and lesions regressed after treatment cessation, leading to the diagnosis of tocilizumab induced sarcoidosis-like reaction. We review the 6 cases reported so far and emphasize the value of a prompt diagnosis. Finally, we discuss the potential pathophysiological mechanisms underlying this rare reaction, which could help to better understand the pathophysiology of sarcoidosis., (© 2021 British Pharmacological Society.)

The management of melanoma is a typical example of a pluridisciplinary approach, in order to provide the patient with a rapid and adequate treatment plan after the initial diagnosis. Both in the domains of dermatology, pathology and oncology, enormous progress has been made. Recent advances permit a rapid access to diagnostic techniques using teledermoscopy, an improved diagnostic accuracy using dermoscopy, pre-interventional high-frequency ultrasound and optical coherence tomography, a determination of risk factors using immunohistochemistry and genetic analyses on the pathology samples. Furthermore, the development of immunotherapies, in particular the anti-PD1 antibodies, and the directed therapies, therapies permitting an increased number of patients to experience an increased survival with an acceptable tolerance profile in the event of metastatic lesions. This article describes the patient's care pathway, from the initial diagnosis, staging, to an eventual treatment and follow-up.

The anatomo-pathological diagnosis of tumors is based on many criteria related mainly to image analysis. Currently, in most pathology laboratories, tissues or cells are placed on glass slides and directly analyzed with an optical microscope. Because of technological evolutions, it is currently possible to digitize slides (digital pathology). The digitization of whole slides has allowed the development of computer programs of artificial intelligence (AI) for image analysis. Applied to tumour pathology, this technology allows the detection, diagnosis or evaluation of the prognosis of neoplastic lesions. There are many challenges associated with the use of AI in routine pathology. These are mainly related to the amount of data to be analyzed and to the development of reliable algorithms. Nevertheless, this technology is promising and could become a valuable aid in the field of precision medicine for which the amount of data related to a patient is constantly increasing.

The hematopoietic system is highly sensitive to perturbations in the translational machinery, of which an emerging level of regulation lies in the epitranscriptomic modification of transfer RNAs (tRNAs). Here, we interrogate the role of tRNA anticodon modifications in hematopoiesis by using mouse models of conditional inactivation of Elp3, the catalytic subunit of Elongator that modifies wobble uridine in specific tRNAs. Loss of Elp3 causes bone marrow failure by inducing death in committing progenitors and compromises the grafting activity of hematopoietic stem cells. Mechanistically, Elp3 deficiency activates a p53-dependent checkpoint in what resembles a misguided amino acid deprivation response that is accompanied by Atf4 overactivation and increased protein synthesis. While deletion of p53 rescues hematopoiesis, loss of Elp3 prompts the development of p53-mutated leukemia/lymphoma, and inactivation of p53 and Elongator cooperatively promotes tumorigenesis. Specific tRNA-modifying enzymes thus condition differentiation and antitumor fate decisions in hematopoietic stem cells and progenitors., Competing Interests: Disclosures: The authors declare no competing interests exist., (© 2021 Rosu et al.)

The oncogenic events involved in breast implant-associated anaplastic large cell lymphoma (BI-ALCL) remain elusive. To clarify this point, we have characterized the genomic landscape of 34 BI-ALCLs (15 tumor and 19 in situ subtypes) collected from 54 BI-ALCL patients diagnosed through the French Lymphopath network. Whole-exome sequencing (n = 22, with paired tumor/germline DNA) and/or targeted deep sequencing (n = 24) showed recurrent mutations of epigenetic modifiers in 74% of cases, involving notably KMT2C (26%), KMT2D (9%), CHD2 (15%), and CREBBP (15%). KMT2D and KMT2C mutations correlated with a loss of H3K4 mono- and trimethylation by immunohistochemistry. Twenty cases (59%) showed mutations in ≥1 member of the JAK/STAT pathway, including STAT3 (38%), JAK1 (18%), and STAT5B (3%), and in negative regulators, including SOCS3 (6%), SOCS1 (3%), and PTPN1 (3%). These mutations were more frequent in tumor-type samples than in situ samples (P = .038). All BI-ALCLs expressed pSTAT3, regardless of the mutational status of genes in the JAK/STAT pathway. Mutations in the EOMES gene (12%) involved in lymphocyte development, PI3K-AKT/mTOR (6%), and loss-of-function mutations in TP53 (12%) were also identified. Copy-number aberration (CNA) analysis identified recurrent alterations, including gains on chromosomes 2, 9p, 12p, and 21 and losses on 4q, 8p, 15, 16, and 20. Regions of CNA encompassed genes involved in the JAK/STAT pathway and epigenetic regulators. Our results show that the BI-ALCL genomic landscape is characterized by not only JAK/STAT activating mutations but also loss-of-function alterations of epigenetic modifiers., (© 2020 by The American Society of Hematology.)

In colorectal cancer staging, pathologic lymph node analysis is a crucial information for the clinician and must be performed with a maximal level of accuracy. Therefore, the surgical sample analysis needs harvesting of as many lymph nodes as possible from the mesentery. In this study, we analysed the influence of a series of clinical and pathological factors which could influence lymph node harvesting. A total of 239 patients were included in our study. The factors with a statistically significant influence on lymph node collection (pinferior to0.05) were the age, gender of the patient, size of the primitive neoplasm, size of the surgical specimen, expertise of the surgeon and the pathology department. The presence of a radiochimiotherapy did not have any influence on the lymph node collection. This study highlights the importance of lymph node harvesting in colorectal surgical specimens of colo-rectal cancers.

Mesenchymal stromal cells (MSCs) exhibit anti-inflammatory and immune-regulatory properties, and preclinical studies suggest a potential benefit in solid organ transplantation. We report on the 1-year follow-up of an open-label phase I-II trial of a single infusion of third-party MSC post-kidney transplantation, in addition to standard immunosuppression. Ten kidney transplant recipients from deceased donors received third-party bone marrow MSCs (∼2 × 10 6 /kg) on day 3 ± 2 post-transplant and were compared to 10 concurrent controls. No adverse effects were noted at MSC injection. One participant with a history of cardiac disease had a non-ST-elevation myocardial infarction approximately 3 hours after MSC infusion. Incidences of opportunistic infections and acute rejection were similar. At day 7 post-transplant, estimated glomerular filtration rate (eGFR) in MSC-treated recipients reached 48.6 ml/min/1.73m 2 , compared to 32.5 ml/min/1.73m 2 in controls and 29.3 ml/min/1.73m 2 in our overall cohort of kidney transplant recipients. No difference in eGFR was found at 1 year. MSC-treated recipients showed increased frequencies of regulatory T cells at day 30, with no significant change in B cell frequencies compared to concurrent controls. Four MSC-treated participants developed antibodies against MSC or shared kidney-MSC HLA, with only 1 with MFI >1500. A single infusion of third-party MSC following kidney transplantation appears to be safe, with one cardiac event of unclear relationship to the intervention. MSC therapy is associated with increased regulatory T cell proportion and with improved early allograft function. Long-term effects, including potential immunization against MSC, remain to be studied., (Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Acute graft-versus-host disease (aGVHD) is a severe complication of allogeneic hematopoietic stem cell transplantation. The role of Th17 cells in its pathophysiology remains a matter of debate. In this study, we assessed whether enrichment of human peripheral blood mononuclear cells (PBMCs) with in vitro Th17-polarized CD4 + T cells would exacerbate xenogeneic GVHD (xGVHD) into NOD-scid IL-2Rγ null (NSG) mice. Naive human CD4 + T cells were stimulated under Th17-skewing conditions for 8 to 10 days and then coinjected in NSG mice with fresh PBMCs from the same donor. We observed that Th17-polarized cells engrafted and migrated toward xGVHD target organs. They also acquired a double-expressing IL-17A + IFNγ + profile in vivo. Importantly, cotransfer of Th17-polarized cells (1 × 10 6 ) with PBMCs (1 × 10 6 ) exacerbated xGVHD compared with transplantation of PBMCs alone (2 × 10 6 ). Furthermore, PBMC cotransfer with Th17-polarized cells was more potent for xGVHD induction than cotransfer with naive CD4 + T cells stimulated in nonpolarizing conditions (Th0 cells, 1 × 10 6  + 1 × 10 6 PBMCs) or with Th1-polarized cells (1 × 10 6  + 1 × 10 6 PBMCs). In summary, our results suggest that human Th17-polarized cells can cooperate with PBMCs and be pathogenic in the NSG xGVHD model., (Copyright © 2018. Published by Elsevier Inc.)

Despite the increasing use of humanized mouse models to study new approaches of graft-versus-host disease (GVHD) prevention, the pathogenesis of xenogeneic GVHD (xGVHD) in these models remains misunderstood. The aim of this study is to describe this pathogenesis in NOD/LtSz-Prkdc scid IL2rγ tm1Wjl (NSG) mice infused with human PBMCs and to assess the impact of the expression of HLA-A0201 by NSG mice cells (NSG-HLA-A2/HHD mice) on xGVHD and graft-versus-leukemia (GvL) effects, by taking advantage of next-generation technologies. We found that T cells recovered from NSG mice after transplantation had upregulated expression of genes involved in cell proliferation, as well as in TCR, co-stimulatory, IL-2/STAT5, mTOR and Aurora kinase A pathways. T cells had mainly an effector memory or an effector phenotype and exhibited a Th1/Tc1-skewed differentiation. TCRβ repertoire diversity was markedly lower both in the spleen and lungs (a xGVHD target organ) than at infusion. There was no correlation between the frequencies of specific clonotypes at baseline and in transplanted mice. Finally, expression of HLA-A0201 by NSG mice led to more severe xGVHD and enhanced GvL effects toward HLA-A2 + leukemic cells. Altogether our data demonstrate that the pathogenesis of xGVHD shares important features with human GVHD and that NSG-HLA-A2/HHD mice could serve as better model to study GVHD and GvL effects.

Mature T cell cancers are typically aggressive, treatment resistant and associated with poor prognosis. Clinical application of immunotherapeutic approaches has been limited by a lack of target antigens that discriminate malignant from healthy (normal) T cells. Unlike B cell depletion, pan-T cell aplasia is prohibitively toxic. We report a new targeting strategy based on the mutually exclusive expression of T cell receptor β-chain constant domains 1 and 2 (TRBC1 and TRBC2). We identify an antibody with unique TRBC1 specificity and use it to demonstrate that normal and virus-specific T cell populations contain both TRBC1 + and TRBC2 + compartments, whereas malignancies are restricted to only one. As proof of concept for anti-TRBC immunotherapy, we developed anti-TRBC1 chimeric antigen receptor (CAR) T cells, which recognized and killed normal and malignant TRBC1 + , but not TRBC2 + , T cells in vitro and in a disseminated mouse model of leukemia. Unlike nonselective approaches targeting the entire T cell population, TRBC-targeted immunotherapy could eradicate a T cell malignancy while preserving sufficient normal T cells to maintain cellular immunity.

Inflammatory bowel diseases are chronic diseases whose long-term evolution depends on the depth of remission. Their clinical and endoscopic evaluation is imperfect. The development of confocal endomicroscopy allows microscopic images to be obtained in vivo. These microscopic data are correlated with the activity of the disease. They predict a possible relapse of the disease and also predict the response to treatment with a biological agent, which allows to modify the therapy before the relapse or to make a rational choice between the different biological agents before introducing a new treatment., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Background & Aims: Mesenchymal stromal cell (MSC) infusion could be a means to establish tolerance in solid organ recipients. The aim of this prospective, controlled, phase I study was to evaluate the feasibility, safety and tolerability of a single infusion of MSCs in liver transplant recipients., Methods: Ten liver transplant recipients under standard immunosuppression received 1.5-3×10 6 /kg third-party unrelated MSCs on postoperative day 3±2, and were prospectively compared to a control group of ten liver transplant recipients. As primary endpoints, MSC infusion toxicity was evaluated, and infectious and cancerous complications were prospectively recorded until month 12 in both groups. As secondary endpoints, rejection rate, month-6 graft biopsies, and peripheral blood lymphocyte phenotyping were compared. Progressive immunosuppression weaning was attempted from month 6 to 12 in MSC recipients., Results: No variation in vital parameters or cytokine release syndrome could be detected during and after MSC infusion. No patient developed impairment of organ functions (including liver graft function) following MSC infusion. No increased rate of opportunistic infection or de novo cancer was detected. As secondary endpoints, there was no difference in overall rates of rejection or graft survival. Month-6 biopsies did not demonstrate a difference between groups in the evaluation of rejection according to the Banff criteria, in the fibrosis score or in immunohistochemistry (including Tregs). No difference in peripheral blood lymphocyte typing could be detected. The immunosuppression weaning in MSC recipients was not successful., Conclusions: No side effect of MSC infusion at day 3 after liver transplant could be detected, but this infusion did not promote tolerance. This study opens the way for further MSC or Treg-based trials in liver transplant recipients., Lay Summary: Therapy with mesenchymal stromal cells (MSCs) has been proposed as a means to improve results of solid organ transplantation. One of the potential MSC role could be to induce tolerance after liver transplantation, i.e. allowing the cessation of several medications with severe side effects. This study is the first-in-man use of MSC therapy in ten liver transplant recipients. This study did not show toxicity after a single MSC infusion but it was not sufficient to allow withdrawal of immunosuppression., Clinical Trial Registration Number: Eudract: # 2011-001822-81, ClinicalTrials.gov: # NCT 01429038., (Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Background: Despite recent advances in colorectal cancer (CRC) diagnosis and population screening programs, the identification of patients with preneoplastic lesions or with early CRC stages remains challenging and is important for reducing CRC incidence and increasing patient's survival., Methods: We analysed 76 colorectal tissue samples originated from early CRC stages, normal or inflamed mucosa by label - free proteomics . The characterisation of three selected biomarker candidates was performed by immunohistochemistry on an independent set of precancerous and cancerous lesions harbouring increasing CRC stages., Results: Out of 5258 proteins identified, we obtained 561 proteins with a significant differential distribution among groups of patients and controls. KNG1, OLFM4 and Sec24C distributions were validated in tissues and showed different expression levels especially in the two early CRC stages compared to normal and preneoplastic tissues., Conclusion: We highlighted three proteins that require further investigations to better characterise their role in early CRC carcinogenesis and their potential as early CRC markers.

Background: Triple-negative breast cancers (TNBC) are heterogeneous cancers with poor prognosis. We aimed to determine the clinical relevance of membrane type-4 matrix metalloproteinase (MT4-MMP), a membrane type matrix metalloproteinase that interacts with epidermal growth factor receptor (EGFR) overexpressed in >50% of TNBC., Methods: We conducted a retrospective immunohistochemical analysis on human TNBC samples (n=81) and validated our findings in in vitro and in vivo assays., Results: Membrane type-4 matrix metalloproteinase and EGFR are produced in 72.5% of TNBC samples, whereas those proteins are faintly produced by healthy tissues. Unexpectedly, tumour relapse after chemotherapy was reduced in samples highly positive for MT4-MMP. Mechanistically, this is ascribed to a higher sensitivity of MT4-MMP-producing cells to alkylating or intercalating chemotherapeutic agents, as assessed in vitro. In sharp contrast, MT4-MMP expression did not affect tumour cell sensitivity to paclitaxel that interferes with protease trafficking. Importantly, MT4-MMP expression sensitised cancer cells to erlotinib, a tyrosine kinase EGFR inhibitor. In a pre-clinical model, the growth of MT4-MMP overexpressing xenografts, but not of control ones, was reduced by epirubicin or erlotinib. The combination of suboptimal drug doses blocked drastically the growth of MT4-MMP-producing tumours., Conclusions: We demonstrate that MT4-MMP defines a sub-population of TNBC sensitive to a combination of DNA-targeting chemotherapeutic agents and anti-EGFR drugs.

Background: Sclerodermatous chronic Graft-versus-Host Disease (scl-cGVHD) is one of the most severe form of cGVHD. The Platelet-derived Grotwth Factor (PDGF) and the Transforming Growth Factor-β (TGF-β) play a significant role in the fibrosing process occurring in scl-cGVHD. This prompted us to assess the impact of the PDGF-r and c-Abl tyrosine kinase inhibitor imatinib on scl-cGVHD., Methods: To assess the impact of imatinib on T cell subset proliferation in vivo, Balb/cJ recipient mice were lethally (7 Gy) irradiated and then injected with 10x106 bone marrow cells from B10.D2 mice on day 0. Fourteen days later, 70x106 carboxyfluorescein succinimidyl ester (CFSE)-labeled splenocytes from B10.D2 mice were infused and imatinib or sterile water was administered for 5 days. To induce severe scl-cGVHD, Balb/cJ mice were injected i.v. with 10.106 bone marrow cells and 70.106 splenocytes from B10.D2 donor mice after 7 Gy irradiation. Mice were then given sterile water or imatinib from day +7 after transplantation to the end of the experiment (day +52)., Results: Imatinib decreased the proliferation of total T cells (P = 0.02), CD8+ T cells (P = 0.01), and of regulatory T cells (Tregs) (P = 0.02) in the spleen. In the severe scl-cGVHD model, imatinib-treated mice had significantly lower levels of PDGF-r phosphorylation than control mice on day 29 after transplantation (P = 0.008). However, scl-cGVHD scores were similar between vehicle- and imatinib-treated mice during the whole experiment, while there was a suggestion for less weight loss in imatinib-treated mice that reached statistical significance at day +52 following transplantation (P = 0.02)., Conclusions: Imatinib had a limited impact in murine scl-cGVHD despite significant inhibition of PDGF-r., Competing Interests: The authors have declared that no competing interests exist.

Background: Previous studies have demonstrated that regulatory T cells (Tregs) play a protective role in the pathogenesis of chronic graft-versus-host disease (cGVHD). Tregs constitutively express the gene of the transcription factor Foxp3 whose CNS2 region is heavily methylated in conventional CD4(+) T cells (CD4(+)Tconvs) but demethylated in Tregs., Methods: Here, we assessed the impact of azacytidine (AZA) on cGVHD in a well-established murine model of sclerodermic cGVHD (B10.D2 (H-2d) → BALB/cJ (H-2d))., Results: The administration of AZA every 48 h from day +10 to day +30 at the dose of 0.5 mg/kg or 2 mg/kg mitigated chronic GVHD. Further, AZA-treated mice exhibited higher blood and thymic Treg frequencies on day +35, as well as higher demethylation levels of the Foxp3 enhancer and the IL-2 promoter in splenocytes at day +52. Interestingly, Tregs from AZA-treated mice expressed more frequently the activation marker CD103 on day +52. AZA-treated mice had also lower counts of CD4(+)Tconvs and CD8(+) T cells from day +21 to day +35 after transplantation, as well as a lower proportion of CD4(+)Tconvs expressing the Ki67 antigen on day +21 demonstrating an anti-proliferating effect of the drug on T cells., Conclusions: Our results indicate that AZA prevented sclerodermic cGVHD in a well-established murine model of cGVHD. These data might serve as the basis for a pilot study of AZA administration for cGVHD prevention in patients at high risk for cGVHD.

Acquisition of an impaired functionality by plasmacytoid dendritic cells (pDCs) contributing to cancer progression has been documented in different types of cancers. In the present study, we postulate that molecules secreted by (pre)neoplastic epithelial cells of the genital tract (cervix/vulva) might attract pDCs but also modify their proper functionality, allowing these cells to initiate a tolerogenic response interfering with antitumor immunity. We demonstrated that pDCs are recruited during the cervical metaplasia-dysplasia-cancer sequence, through the action of their chemoattractant, chemerin. We showed that stimulated-pDCs exposed to cervical/vulvar tumor microenvironment display an altered phenotype. We also demonstrated that cervical/vulvar neoplastic keratinocytes inhibit the proper function of pDCs by decreasing their IFNα secretion in response to CpG oligonucleotides. In parallel, we observed that (pre)neoplastic areas of the cervix are infiltrated by FoxP3(+) Treg cells which colocalize with pDCs. Accordingly, pDCs cocultured with cervical/vulvar neoplastic keratinocytes have the capacity to induce a Treg cell differentiation from naïve CD4(+) T cells, which is in agreement with the development of a tolerogenic response. We identified HMGB1 as a soluble factor produced by neoplastic keratinocytes from the genital tract involved in pDCs functional alteration. Indeed, this molecule inhibited pDC maturation, decreased IFNα secretion following TLR9 stimulation and forced these cells to become tolerogenic. In contrast, inhibition of HMGB1 restored pDC phenotype. Our findings indicate that the use of inhibitory molecules notably directed against HMGB1 in cervical/vulvar (pre)neoplastic lesions might prevent alterations of pDCs functionality and represent an attractive therapeutic strategy to overcome immune tolerance in cancers., (© 2014 UICC.)

Regulatory T cells (Tregs) are essential to prevent autoimmunity, but excessive Treg function contributes to cancer progression by inhibiting antitumor immune responses. Tregs exert contact-dependent inhibition of immune cells through the production of active transforming growth factor-β1 (TGF-β1). On the Treg cell surface, TGF-β1 is in an inactive form bound to membrane protein GARP and then activated by an unknown mechanism. We demonstrate that GARP is involved in this activation mechanism. Two anti-GARP monoclonal antibodies were generated that block the production of active TGF-β1 by human Tregs. These antibodies recognize a conformational epitope that requires amino acids GARP137-139 within GARP/TGF-β1 complexes. A variety of antibodies recognizing other GARP epitopes did not block active TGF-β1 production by Tregs. In a model of xenogeneic graft-versus-host disease in NSG mice, the blocking antibodies inhibited the immunosuppressive activity of human Tregs. These antibodies may serve as therapeutic tools to boost immune responses to infection or cancer via a mechanism of action distinct from that of currently available immunomodulatory antibodies. Used alone or in combination with tumor vaccines or antibodies targeting the CTLA4 or PD1/PD-L1 pathways, blocking anti-GARP antibodies may improve the efficiency of cancer immunotherapy., (Copyright © 2015, American Association for the Advancement of Science.)

The progression of genital human papillomavirus (HPV) infections into preneoplastic lesions suggests that infected/malignant cells are not adequately recognized by the immune system. In this study, we demonstrated that cervical/vulvar cancer cells secrete factor(s) that affect both the maturation and function of dendritic cells (DC) leading to a tolerogenic profile. Indeed, DC cocultured with cancer cell lines display both a partially mature phenotype after lipopolysaccharide (LPS) maturation and an altered secretory profile (IL-10 high and IL-12p70 low ). In addition, tumor-converted DC acquire the ability to alter T-cell proliferation and to induce FoxP3 + suppressive T cells from naive CD4 + T cells. Among the immunosuppressive factors implicated in DC alterations in genital (pre)neoplastic microenvironment, we identified receptor activator of nuclear factor kappa-B ligand (RANKL), a TNF family member, as a potential candidate. For the first time, we showed that RANKL expression strongly increases during cervical progression. We also confirmed that RANKL is directly secreted by cancer cells and this expression is not related to HPV viral oncoprotein induction. Interestingly, the addition of osteoprotegerin (OPG) in coculture experiments reduces significantly the inhibition of DC maturation, the release of a tolerogenic cytokine profile (IL-12 low IL-10 high ) and the induction of regulatory T (Treg) cells. Our findings suggest that the use of inhibitory molecules directed against RANKL in cervical/vulvar (pre)neoplastic lesions might prevent alterations of DC functionality and represent an attractive strategy to overcome immune tolerance in such cancers.

Unlabelled: This study aimed to correlate (18)F-FB-mini-PEG-E[c(RGDyK)](2) ((18)F-FPRGD2) uptake to integrin αvβ3 expression and angiogenesis in renal tumors., Methods: (18)F-FPRGD2 PET/CT was performed on 27 patients before surgical resection (median 4 d) of a renal mass. The (18)F-FPRGD2 uptake was compared with integrin αvβ3, CD31, CD105, and Ki-67 using immunohistochemistry; with placental growth factor and vascular endothelial growth factor receptors 1 and 2 using reverse transcription polymerase chain reaction; and with vascular endothelial growth factor A isoforms using enzyme-linked immunosorbent assay., Results: Overall, (18)F-FPRGD2 uptake significantly correlated (P < 0.0001) with integrin αvβ3 expression in renal masses. However, it correlated only with integrin αvβ3-positive vessels in the group of papillary carcinomas whereas it correlated with integrin αvβ3 expression by tumor cells in the clear cell carcinoma group., Conclusion: (18)F-FPRGD2 uptake reflects the expression of integrin αvβ3 in renal tumors but represents angiogenesis only when tumor cells do not express the integrin., (© 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Recent studies have identified a putative cell of origin for cervical intraepithelial neoplasia (CIN) and cervical cancer at the squamocolumnar junction (SCJ) and suggest that these cells may not regenerate after excision (loop electrosurgical excision procedure). Our study addressed the impact of SCJ excision on the temporal dynamics, histologic and viral (human papillomavirus, HPV) characteristics of recurrent CIN. One hundred and thirty-one consecutive patients treated by excision and attending follow-up visits were enrolled. We compared recurrent and initial CIN with attention to excision margins, timing of recurrence, CIN grade, HPV types, p16 immunophenotype and SCJ immunophenotype. During the follow-up period (up to 4 years), 16 (12.2%) recurrences were identified. Four (25%) were identified at the first follow-up visit, closely resembled the initial CIN 2/3 in grade and HPV type and were typically SCJ marker positive [SCJ(+)], suggesting nonexcised (residual) disease. Twelve (75%) manifested after the first postoperative visit and all were in the ectocervix or in mature metaplastic epithelium. All of the 12 delayed recurrences were classified as CIN 1 and were SCJ (-). In total, 9 out of 11 SCJ (-) recurrences (82%) followed regressed spontaneously. Taken together, these results show that new lesions developing from any HPV infection are delayed and occur within the ectocervix or metaplastic epithelium. This markedly lower risk of CIN 2/3 after successful SCJ excision suggests that the removal of the SCJ could be a critical variable in reducing the risk of subsequent CIN 2/3 and cervical cancer., (© 2014 UICC.)