Ashis Mondal

Gender-specific differential expression of exosomal miRNA in synovial fluid of patients with osteoarthritis

The pathogenesis of osteoarthritis (OA) is poorly understood, and therapeutic approaches are limited to preventing progression of the disease. Recent studies have shown that exosomes play a vital role in cell-to-cell communication, and pathogenesis of many age-related diseases. Molecular profiling of synovial fluid derived exosomal miRNAs may increase our understanding of OA progression and may lead to the discovery of novel biomarkers and therapeutic targets. In this article we report the first characterization of exosomes miRNAs from human synovial fluid. The synovial fluid exosomes share similar characteristics (size, surface marker, miRNA content) with previously described exosomes in other body fluids. MiRNA microarray analysis showed OA specific exosomal miRNA of male and female OA. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identified gender-specific target genes/signaling pathways. These pathway analyses showed that female OA specific miRNAs are estrogen responsive and target TLR (toll-like receptor) signaling pathways. Furthermore, articular chondrocytes treated with OA derived extracellular vesicles had decreased expression of anabolic genes and elevated expression of catabolic and inflammatory genes. In conclusion, synovial fluid exosomal miRNA content is altered in patients with OA and these changes are gender specific.

A novel immunohistochemical score to predict early mortality in acute myeloid leukemia patients based on indoleamine 2,3 dioxygenase expression

Indoleamine 2,3 dioxygenase-1 (IDO-1) is an enzyme in the kynurenine pathway which augments tumor-induced immune tolerance. Previous studies in childhood acute myeloid leukemia (AML) have shown a negative correlation of IDO-1 mRNA expression with outcomes. The aim of our study was to develop a practical and objective immunohistochemical technique to quantify IDO-1 expression on diagnostic bone marrow biopsies of AML patients in order to facilitate its use in routine clinical practice. IDO-1 mRNA was extracted from diagnostic bone marrow specimens from 29 AML patients. IDO-1 protein expression was assessed in 40 cases via immunohistochemistry and quantified by a novel ‘composite IDO-1 score’. In a univariate analysis, higher age (p = 0.0018), male gender (p = 0.019), high risk cytogenetics (p = 0.002), higher IDO-1 mRNA (p = 0.005), higher composite IDO-1 score (p < 0.0001) and not undergoing allogeneic stem cell transplant (SCT, p = 0.0005) predicted poor overall survival. In a multivariate model that included the aforementioned variables, higher composite IDO-1 score (p = 0.007) and not undergoing allogeneic SCT (p = 0.007) was found to significantly predict poor outcomes. Further, patients who failed induction had higher composite IDO-1 score (p = 0.01). In conclusion, ‘composite IDO-1 score’ is a prognostic tool that can help identify a certain subset of AML patients with ‘early mortality’. This unique subset of patients can potentially benefit from specific IDO-1 inhibitor therapy, currently in clinical trials.

Modulation of miRNAs by Vitamin C in Human Bone Marrow Stromal Cells

MicroRNAs (miRNAs) are small (18–25 nucleotides), noncoding RNAs that have been identified as potential regulators of bone marrow stromal cell (BMSC) proliferation, differentiation, and musculoskeletal development. Vitamin C is known to play a vital role in such types of biological processes through various different mechanisms by altering mRNA expression. We hypothesized that vitamin C mediates these biological processes partially through miRNA regulation. We performed global miRNA expression analysis on human BMSCs following vitamin C treatment using microarrays containing human precursor and mature miRNA probes. Bioinformatics analyses were performed on differentially expressed miRNAs to identify novel target genes and signaling pathways. Our bioinformatics analysis suggested that the miRNAs may regulate multiple stem cell-specific signaling pathways such as cell adhesion molecules (CAMs), fatty acid biosynthesis and hormone signaling pathways. Furthermore, our analysis predicted novel stem cell proliferation and differentiation gene targets. The findings of the present study demonstrate that vitamin C can have positive effects on BMSCs in part by regulating miRNA expression.

miRNA in Pathophysiology of Peripartum Cardiomyopathy (PPCM): A Systemic Review

Peripartum cardiomyopathy (PPCM) was recognized as a clinical entity in the early 1930s; however, the exact mechanism of the disease’s progression remains unknown. The highest incidence of PPCM is in African Americans, and the disease is associated with poor outcomes in elderly and multiparous women. The varying characteristics of patients suggest that genetic susceptibility of the disease could exist. PPCM can be associated with life threatening complications including cardiogenic shock, fatal arrhythmias, and thromboembolic events which can lead to death. Pregnant or lactating PPCM patients can further complicate how clinicians manage them. One recent hypothesis is that 16-kDa N-terminal prolactin fragment (16K PRL) plays a vital role in PPCM by inducing microRNA146a (miRNA146a) which reduces angiogenesis through downregulation of NRAS. miRNAs are small RNAs that were previously described as noncoding RNA that controls the posttranscriptional activity of mRNA. Recent animal studies have identified miRNA146a as a causative factor in PPCM; this discovery is promising and could have clinical implications in future. With growing evidence of miRNA’s involvement in disease, miRNA can add to our current understanding of pathology and could be a potential tool for diagnosis, prognosis, and therapy in PPCM.

Utility and impact of early t(15;17) identification by Fluorescence In Situ Hybridization (FISH) in clinical decision making for patients in Acute Promyelocytic Leukemia (APL)

Acute Promyelocytic Leukemia (APL) is a curable malignancy with studies showing above 90% survival. However, population‐based studies looking at survival suggest that approximately 30% of patients with APL die during induction. Early demonstration of t(15;17) will lead to accurate decision making regarding treatment. The aim of this project was to validate earlier time frames for the Abbott Molecular Vysis LSI promyelocytic leukemia (PML)/ retinoic acid receptor alpha (RARA) fluorescence in situ hybridization (FISH) probe (ASR 6–16 h).

TIMP-1 downregulation modulates miR-125a-5p expression and triggers the apoptotic pathway

Matrix metalloproteinases and their natural inhibitors (TIMPs) are important elements in a wide range of oncology settings. Elevated levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) have often been associated with increased tumorigenesis. This has been demonstrated in a number of clinical and experimental models which include breast, gastric, colorectal and non-small cell lung carcinoma (NSCLC). Our earlier studies have identified increased angiogenic activity and aggressive tumor kinetics in TIMP-1 overexpressing H2009 lung adenocarcinoma cells. TIMP-1 overexpression has also been implicated in antiapoptotic responses, inducing a significant upregulation of Bcl-2. These TIMP-1 functions have been shown to be MMP-independent and provide insight into its pleiotropic activities. The current study examines microRNA (miRNA) interactions with this molecule. We have sought to define the relationship between TIMP-1 and miRNA by knocking down TIMP-1 in high TIMP-1 expressing lung adenocarcinoma cell lines. TIMP-1 knockdown resulted in increased expression of miR-125a-5p with a concomitant increase in apoptosis and attenuation of the tumorigenic features of these cells. We have identified TIMP-1 as a bona fide target of miR-125a-5p, and their interaction resulted in an increase in p53 expression. We further corroborated our in vitro data with patient samples, which exhibited an inverse correlation between TIMP-1 and miR-125a-5p expression. Our study lends support to the notion that elevated TIMP-1 levels, which are frequently associated with poor prognosis, cause aberrant modulation of miRNAs.

Delineating Pro-Angiogenic Myeloid Cells in Cancer Therapy

Recent evidence suggests that myeloid cells are critical in cancer development and therapy resistance processes. Pharmacological targeting of tumor-associated myeloid cells is an emerging approach among upcoming immune therapies. Surprisingly, myeloid cells are heterogeneous, including a subset of the myeloid cell displaying angiogenic properties in solid tumors. There is an urgent need to delineate angiogenic myeloid cell populations in order to facilitate specific targeting of protumor myeloid cells among heterogeneous pool. This review article is intended to compile all the relevant information in the literature for improved understanding of angiogenic myeloid cells and their role in tumor refractoriness to cancer therapy.

Modulation in the microRNA repertoire is responsible for the stage-specific effects of Akt suppression on murine neuroendocrine prostate cancer

Recent studies indicate a stage-specific, differential role for the oncogene Akt on various cancers. In prostate cancer (PCa), suppression of Akt activity in the advanced stages promoted transforming growth factor-β (TGFβ) pathway-mediated epithelial-to-mesenchymal transition (EMT) and metastasis to the lungs. In the current study, we performed Affymetrix analysis to compare the expression profile of microRNAs in the mouse prostate tissues collected at the prostatic inter-epithelial neoplasia (PIN) stage from Transgenic adenocarcinoma of the mouse (TRAMP)/Akt1+/+ versus TRAMP/Akt1–/– mice, and at the advanced stage from TRAMP/Akt1+/+ mice treated with triciribine (Akt inhibitor) versus DMSO-treated control. Our analysis demonstrates that in the early stage, Akt1 in the TRAMP prostate tumors express a set of miRNAs responsible for regulating cancer cell survival, proliferation, and tumor growth, whereas, in the advanced stages, a different set of miRNAs that promote EMT and cancer metastasis is expressed. Our study has identified novel Akt-regulated signature microRNAs in the early and advanced PCa and demonstrates their differential effects on PCa growth and metastasis.

Prognostic value of complete remission with superior platelet counts in acute myeloid leukemia.

BACKGROUND Complete remission (CR) in acute myeloid leukemia (AML) is defined as having ≤5% leukemic blast cells in the bone marrow and return of normal hematopoiesis after the first induction cycle. There is a subset of patients, however, who achieve reduction of leukemic blast cells with a subnormal platelet count, designated as CR with incomplete platelet recovery (platelet count, ≤100,000/mcL; normal, 150,000-450,000/mcL), which is associated with inferior outcomes when compared with CR. Furthermore, there is another subset of patients with CR but superior platelet counts (≥400,000/mcL) whose prognostic significance is unclear. OBJECTIVE To establish whether CR with superior platelet counts is associated with better outcomes and can be used as a separate entity for prognostication. METHODS A retrospective chart review of 104 cases of AML was conducted. The highest platelet count during days 25-35 from initiation of induction chemotherapy (designated as day 30 platelet count) was documented. A multivariate analysis for other factors such as age, sex, risk categories, day 14+ plasma cell count (average plasma cell percentage at days 14-21), infections, allogeneic bone marrow transplant, and remission status was done. RESULTS Day 30 platelet count was found to be an independent predictor of survival in AML. On the multivariate analysis, the subgroup with superior platelet counts (≥400,000/mcL) was found to be associated with better outcomes. LIMITATIONS Results need to be validated in a larger cohort. CONCLUSIONS CR with superior platelet recovery (≥400,000/mcL) is a unique subcategory in itself and has prognostic significance. This may help better assess response to chemotherapeutic agents and aid in further decision-making regarding treatment.

Abstract 3961: Utility of mir-21 detection by rapid chromogenic in-situ hybridization in the diagnosis of well and moderately differentiated hepatocellular carcinoma

Background: An estimated 80-90% of all hepatocellular carcinomas (HCC) arise from cirrhotic liver in chronic hepatitis B or C infection. Identifying well-differentiated HCC arising in the background of cirrhosis is a challenging task relying solely on morphology of core biopsies. In addition, presence of dysplasia (micro/macro) in cirrhotic nodules makes the task more difficult. In HCC, microRNAs (miRNAs) have an aberrant expression profile with possible applications in diagnosis, especially for early, symptomatic disease. Sub-cellular and tissue localization of miRNAs may help us understand their biological roles and contribution to disease along with aiding diagnosis. Design: The aim of this study was to evaluate the utility of mir-21 detection by rapid chromogenic in-situ hybridization (CISH) as a diagnostic tool in the setting of well and moderately differentiated HCCs. Archival blocks and slides were retrieved and reviewed after obtaining IRB approval (table 1). Manufacturers guidelines were followed for CISH (NAR-1, FAM-labeled Has-miR-21 probe) on a total of 202 cases. Nuclear mir-21 CISH stain was graded as: negative (-), weak (1+), moderate (2+) or strong (3+) and distribution was graded as: focal ( 50%). Results: Neoplastic cells in HCC showed a strong (2-3) multifocal to diffuse nuclear staining for mir-21 in 100% of the cases of whole tissue slides and 91% of HCC cases in tissue microarray slides when compared to the staining pattern seen in normal liver cells (0%). As expected, 85% of cases with liver metastases from colonic and gallbladder adenocarcinoma showed strong nuclear staining for mir-21. Conclusion: Rapid CISH technique can clearly identify increased nuclear expression of mir-21 and aid in diagnosis of well and moderately differentiated HCC. Citation Format: Ravindra Kolhe, Amyn Rojiani, Ashis Mondal, Abhishek A. Mangaonkar. Utility of mir-21 detection by rapid chromogenic in-situ hybridization in the diagnosis of well and moderately differentiated hepatocellular carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3961. doi:10.1158/1538-7445.AM2015-3961