miRNA Expression in Fibroblastic Foci within Idiopathic Pulmonary Fibrosis Lungs Reveals Novel Disease-Relevant Pathways.

miRNAs are 22 nucleotides long and belong to a class of noncoding RNAs that plays an important role in regulating gene expression at a post-transcriptional level. Studies show aberrant levels of miRNAs to be associated with profibrotic processes in idiopathic pulmonary fibrosis (IPF). However, most of these studies used whole IPF tissue or in vitro monocultures in which fibrosis was artificially induced. The current study used laser microdissection to collect fibroblastic foci (FF), the key pathologic lesion in IPF, isolated miRNAs, and compared their expression levels with those found in whole IPF lung tissue and/or in vitro cultured fibroblast from IPF or normal lungs. Sequencing libraries were generated, and data generated were bioinformatically analyzed. A total of 18 miRNAs were significantly overexpressed in FF tissue when compared with whole IPF tissue. Of those, 15 were unique to FF. Comparison of FF with cultured IPF fibroblasts also revealed differences in miRNA composition that impacted several signaling pathways. The miRNA composition of FF is both overlapping and distinct from that of whole IPF tissue or cultured IPF fibroblasts and highlights the importance of characterizing FF biology as a phenotypically and functionally discrete tissue microenvironment.

c-Rel-dependent Chk2 signaling regulates the DNA damage response limiting hepatocarcinogenesis.

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death. The NF-κB transcription factor family subunit c-Rel is typically protumorigenic; however, it has recently been reported as a tumor suppressor. Here, we investigated the role of c-Rel in HCC. APPROACH AND RESULTS: Histological and transcriptional studies confirmed expression of c-Rel in human patients with HCC, but low c-Rel expression correlated with increased tumor cell proliferation and mutational burden and was associated with advanced disease. In vivo , global ( Rel-/- ) and epithelial specific ( RelAlb ) c-Rel knockout mice develop more tumors, with a higher proliferative rate and increased DNA damage, than wild-type (WT) controls 30 weeks after N-diethylnitrosamine injury. However, tumor burden was comparable when c-Rel was deleted in hepatocytes once tumors were established, suggesting c-Rel signaling is important for preventing HCC initiation after genotoxic injury, rather than for HCC progression. In vitro , Rel-/- hepatocytes were more susceptible to genotoxic injury than WT controls. ATM-CHK2 DNA damage response pathway proteins were suppressed in Rel-/- hepatocytes following genotoxic injury, suggesting that c-Rel is required for effective DNA repair. To determine if c-Rel inhibition sensitizes cancer cells to chemotherapy, by preventing repair of chemotherapy-induced DNA damage, thus increasing tumor cell death, we administered single or combination doxorubicin and IT-603 (c-Rel inhibitor) therapy in an orthotopic HCC model. Indeed, combination therapy was more efficacious than doxorubicin alone. CONCLUSION: Hepatocyte c-Rel signaling limits genotoxic injury and subsequent HCC burden. Inhibiting c-Rel as an adjuvant therapy increased the effectiveness of DNA damaging agents and reduced HCC growth.

Impact of risk scores in outcome of patients with myeloid neoplasms after allogeneic stem cell transplant / Impacto de las puntaciones del riesgo en los resultados de los pacientes con neoplasias mieloides tras el trasplante alogénico de células madre

Background:The main causes of failure of allogeneic hematopoietic stem cell transplantation (allo-transplant) in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are relapse and transplant-related mortality. Different scores have been designed to predict the prognosis of these patients. The objective of this study was to assess which score or combination has better outcome predictive capacity.Methods:Retrospective analysis of patients with AML and MDS who received a first peripheral blood allo-transplant in a single center, between December 2001 and October 2019. Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), European Group for Blood and Marrow Transplantation (EBMT) and Disease Risk Index (DRI) scores were calculated. For each score and for the HCT-CI/DRI and HCT-CI/EBMT combinations, overall survival (OS), cumulative incidence of relapse (CIR), non-relapse-related mortality (NRM), and graft versus host disease-free relapse-free survival (GRFS) were analyzed.Results:175 patients were evaluated. With a median (range) follow-up of 3.96 (0.32–17.22) years, the 5-year probabilities (95% CI) of OS, CIR, NRM, and GRFS were 36% (28%–44%), 28% (21%–35%), 38% (30%–46%) and 24% (17%–31%), respectively. For OS, only the DRI score selected two groups with statistically significant differences (DRI 0–1: 41% vs. DRI ≥2: 24%; p=0.011). The combination of DRI 0–1 and HCT-CI 0–2 showed OS probabilities of 45% vs. 26% for those with DRI 0–1 and HCT-CI ≥3; p=0.041.Conclusions:In patients with AML and MDS submitted to allo-transplant, the combination of HCT-CI and DRI scores provided the best stratification for OS. (AU)

Antecedentes:Las principales causas de fallo del trasplante alogénico de células madre hematopoyéticas (alotrasplante) en pacientes con leucemia mieloide aguda (LMA) y síndromes mielodisplásicos (SMD) son las recaídas y la mortalidad debida al trasplante. Se han diseñado diferentes puntuaciones para predecir el pronóstico de dichos pacientes. El objetivo de este estudio fue evaluar qué puntuación o combinación tiene la mejor capacidad predictiva del resultado.Métodos:Análisis retrospectivo de pacientes con LMA y SMD que recibieron un primer alotrasplante de sangre periférica en un único centro, entre diciembre de 2001 y octubre de 2019. Se calcularon las puntuaciones del Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), del European Group for Blood and Marrow Transplantation (EBMT) y del Disease Risk Index (DRI). Para cada puntuación y para las combinaciones HCT-CI/DRI y HCT-CI/EBMT se analizaron la supervivencia global (SG), la incidencia acumulada de recaídas (CIR), la mortalidad no relativa a las recaídas (NRM) y la supervivencia libre de recaídas y libre de enfermedad de injerto versus huésped (GRFS).Resultados:Se evaluaron 175 pacientes. Con un seguimiento medio (rango) de 3,96 (0,32-17,22) años, las probabilidades a 5años (IC95%) de SG, CIR, NRM y GRFS fueron del 36% (28-44), del 28% (21-35), del 38% (30-46) y del 24% (17-31), respectivamente. Para la SG, solo la puntuación DRI seleccionó dos grupos con diferencias estadísticamente significativas (DRI 0-1: 41% vs. DRI≥2: 24%; p=0,011). La combinación de DRI 0-1 y HCT-CI 0-2 reflejó probabilidades de SG del 45% vs. 26% para los pacientes con DRI 0-1 y HCT-CI≥3 (p=0,041).Conclusiones:En los pacientes con LMA y SMD sometidos a alotrasplante la combinación de las puntuaciones HCT-CI y DRI proporcionó la mejor estratificación para la SG. (AU)

Impact of risk scores in outcome of patients with myeloid neoplasms after allogeneic stem cell transplant.

BACKGROUND: The main causes of failure of allogeneic hematopoietic stem cell transplantation (allo-transplant) in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are relapse and transplant-related mortality. Different scores have been designed to predict the prognosis of these patients. The objective of this study was to assess which score or combination has better outcome predictive capacity. METHODS: Retrospective analysis of patients with AML and MDS who received a first peripheral blood allo-transplant in a single center, between December 2001 and October 2019. Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), European Group for Blood and Marrow Transplantation (EBMT) and Disease Risk Index (DRI) scores were calculated. For each score and for the HCT-CI/DRI and HCT-CI/EBMT combinations, overall survival (OS), cumulative incidence of relapse (CIR), non-relapse-related mortality (NRM), and graft versus host disease-free relapse-free survival (GRFS) were analyzed. RESULTS: 175 patients were evaluated. With a median (range) follow-up of 3.96 (0.32-17.22) years, the 5-year probabilities (95% CI) of OS, CIR, NRM, and GRFS were 36% (28%-44%), 28% (21%-35%), 38% (30%-46%) and 24% (17%-31%), respectively. For OS, only the DRI score selected two groups with statistically significant differences (DRI 0-1: 41% vs. DRI ≥2: 24%; p=0.011). The combination of DRI 0-1 and HCT-CI 0-2 showed OS probabilities of 45% vs. 26% for those with DRI 0-1 and HCT-CI ≥3; p=0.041. CONCLUSIONS: In patients with AML and MDS submitted to allo-transplant, the combination of HCT-CI and DRI scores provided the best stratification for OS.

Obesity and Roux-en-Y gastric bypass drive changes in miR-31 and miR-215 expression in the human rectal mucosa.

BACKGROUND/OBJECTIVES: Obesity increases colorectal cancer (CRC) risk. However, the effects of weight loss on CRC risk are unclear. Epigenetic mechanisms involving microRNAs that lead to dysregulated gene expression may mediate the effects of obesity and weight loss on CRC risk. We examined the effects of obesity and weight loss following Roux-en-Y gastric bypass (RYGB) on microRNA expression in the human rectal mucosa. SUBJECTS/METHODS: We collected rectal mucosal biopsies from obese patients (n = 22) listed for RYGB and age- and sex-matched healthy non-obese Controls (n = 20), at baseline and six months post-surgery. We quantified microRNA expression in rectal mucosal biopsies using Next Generation Sequencing and bioinformatics analysis to investigate the likely functional consequences of these epigenetic changes. RESULTS: Compared with non-obese individuals, obese individuals showed differential expression of 112 microRNAs (p < 0.05). At six-months post-RYGB, when mean body mass had fallen by 27 kg, 60 microRNAs were differentially expressed, compared with baseline (p < 0.05). The expression of 36 microRNAs differed significantly between both i) obese and non-obese individuals and ii) obese individuals pre- and post-RYGB. Quantitative polymerase chain reaction (qPCR) demonstrated that expression of miR-31 and miR-215 was significantly (p < 0.05) higher, 143-fold and 15-fold respectively, in obese than in non-obese individuals. Weight loss, following RYGB, reduced expression of miR-31 and miR-215 to levels comparable with Controls. These differentially expressed microRNAs are implicated in pathways linked with inflammation, obesity and cancer. CONCLUSION: Our findings show, for the first time, that obesity is associated with dysregulated microRNA expression in the human rectal mucosa. Further, surgically-induced weight loss may normalise microRNA expression in this tissue.

RNA sequencing reveals changes in the microRNAome of transdifferentiating hepatic stellate cells that are conserved between human and rat.

MicroRNAs are small (~ 22nt long) noncoding RNAs (ncRNAs) that regulate gene expression at the post-transcriptional level. Over 2000 microRNAs have been described in humans and many are implicated in human pathologies including tissue fibrosis. Hepatic stellate cells (HSC) are the major cellular contributors to excess extracellular matrix deposition in the diseased liver and as such are important in the progression of liver fibrosis. We employed next generation sequencing to map alterations in the expression of microRNAs occurring across a detailed time course of culture-induced transdifferentiation of primary human HSC, this a key event in fibrogenesis. Furthermore, we compared profiling of human HSC microRNAs with that of rat HSC so as to identify those molecules that are conserved with respect to modulation of expression. Our analysis reveals that a total of 229 human microRNAs display altered expression as a consequence of HSC transdifferentiation and of these 104 were modulated early during the initiation phase. Typically modulated microRNAs were targeting kinases, transcription factors, chromatin factors, cell cycle regulators and growth factors. 162 microRNAs changed in expression during transdifferentiation of rat HSC, however only 17 underwent changes that were conserved in human HSC. Our study therefore identifies widespread changes in the expression of HSC microRNAs in fibrogenesis, but suggests a need for caution when translating data obtained from rodent HSC to events occurring in human cells.

Fibrogenic Activity of MECP2 Is Regulated by Phosphorylation in Hepatic Stellate Cells.

BACKGROUND & AIMS: Methyl-CpG binding protein 2, MECP2, which binds to methylated regions of DNA to regulate transcription, is expressed by hepatic stellate cells (HSCs) and is required for development of liver fibrosis in mice. We investigated the effects of MECP2 deletion from HSCs on their transcriptome and of phosphorylation of MECP2 on HSC phenotype and liver fibrosis. METHODS: We isolated HSCs from Mecp2-/y mice and wild-type (control) mice. HSCs were activated in culture and used in array analyses of messenger RNAs and long noncoding RNAs. Kyoto Encyclopedia of Genes and Genomes pathway analyses identified pathways regulated by MECP2. We studied mice that expressed a mutated form of Mecp2 that encodes the S80A substitution, MECP2S80, causing loss of MECP2 phosphorylation at serine 80. Liver fibrosis was induced in these mice by administration of carbon tetrachloride, and liver tissues and HSCs were collected and analyzed. RESULTS: MECP2 deletion altered expression of 284 messenger RNAs and 244 long noncoding RNAs, including those that regulate DNA replication; are members of the minichromosome maintenance protein complex family; or encode CDC7, HAS2, DNA2 (a DNA helicase), or RPA2 (a protein that binds single-stranded DNA). We found that MECP2 regulates the DNA repair Fanconi anemia pathway in HSCs. Phosphorylation of MECP2S80 and its putative kinase, HAS2, were induced during transdifferentiation of HSCs. HSCs from MECP2S80 mice had reduced proliferation, and livers from these mice had reduced fibrosis after carbon tetrachloride administration. CONCLUSIONS: In studies of mice with disruption of Mecp2 or that expressed a form of MECP2 that is not phosphorylated at S80, we found phosphorylation of MECP2 to be required for HSC proliferation and induction of fibrosis. In HSCs, MECP2 regulates expression of genes required for DNA replication and repair. Strategies to inhibit MECP2 phosphorylation at S80 might be developed for treatment of liver fibrosis.

A novel simulator model and standardized assessment tools for fine needle aspiration cytology training.

OBJECTIVES: Fine needle aspiration (FNA) is an invaluable diagnostic procedure for evaluation of lesions; however, acquisition of diagnostic material is dependent on the skill of the practitioner. We report a novel patient simulator for teaching the FNA procedure and structured assessment tools for educators and learners. METHODS: We created a novel simulator model for FNA training, employed a standardized teaching module, and assessed procedure utility in medical students. Groups of students completed training using a commercial version of the model, and underwent structured evaluation using an Objective Structured Assessment of Technical Skills (OSATS) form, and the Debriefing Assessment for Simulation in Healthcare (DASH) tool. RESULTS: In the initial phase, 178 students rated the training workshop between valuable and essential (4.2 on a 5-point Likert scale). In the second phase, for students evaluated with the OSATS form, the mean overall score was 33 out of 50 (range 26-43). The areas of weakness for the participants were: (a) compression after the FNA procedure, (b) completion of the informed consent, and (c) correct explanation of the procedure to the patient. For the group of students that completed the DASH questionnaire, the results were: 6.2 (assessment by students) and 6.7 (assessment by instructor) out of a maximum of 7. CONCLUSION: A realistic simulation model, in combination with a standardized training program with formal assessment methods is a valuable tool to teach FNA. We here describe a process for teaching the FNA procedure to interested educators and learners.

A Proof-of-Concept for Epigenetic Therapy of Tissue Fibrosis: Inhibition of Liver Fibrosis Progression by 3-Deazaneplanocin A.

The progression of fibrosis in chronic liver disease is dependent upon hepatic stellate cells (HSCs) transdifferentiating to a myofibroblast-like phenotype. This pivotal process is controlled by enzymes that regulate histone methylation and chromatin structure, which may be targets for developing anti-fibrotics. There is limited pre-clinical experimental support for the potential to therapeutically manipulate epigenetic regulators in fibrosis. In order to learn if epigenetic treatment can halt the progression of pre-established liver fibrosis, we treated mice with the histone methyltransferase inhibitor 3-deazaneplanocin A (DZNep) in a naked form or by selectively targeting HSC-derived myofibroblasts via an antibody-liposome-DZNep targeting vehicle. We discovered that DZNep treatment inhibited multiple histone methylation modifications, indicative of a broader specificity than previously reported. This broad epigenetic repression was associated with the suppression of fibrosis progression as assessed both histologically and biochemically. The anti-fibrotic effect of DZNep was reproduced when the drug was selectively targeted to HSC-derived myofibroblasts. Therefore, the in vivo modulation of HSC histone methylation is sufficient to halt progression of fibrosis in the context of continuous liver damage. This discovery and our novel HSC-targeting vehicle, which avoids the unwanted effects of epigenetic drugs on parenchymal liver cells, represents an important proof-of-concept for epigenetic treatment of liver fibrosis.

First case of fulminant sepsis due to Wohlfahrtiimonas chitiniclastica.

We report the first case of fulminant sepsis due to Wohlfahrtiimonas chitiniclastica. This case is also the first one reported in South America. We emphasize the importance of recognizing bacteria that live in the larvae of a parasitic fly as the causative agent of severe infections in homeless patients.