Identification of miR-15b as a transformation-related factor in mantle cell lymphoma

An miRNA Signature Predicts Grading of Pancreatic Neuroendocrine Neoplasms

BACKGROUND/AIM

Grading pancreatic neuroendocrine neoplasms (PNENs) via mitotic rate and Ki-67 index score is complicated by interobserver variability. Differentially expressed miRNAs (DEMs) are useful for predicting tumour progression and may be useful for grading.

PATIENTS AND METHODS

Twelve PNENs were selected. Four patients had grade (G) 1 pancreatic neuroendocrine tumours (PNETs); 4 had G2 PNETs; and 4 had G3 PNENs (2 PNETs and 2 pancreatic neuroendocrine carcinomas). Samples were profiled using the miRNA NanoString Assay.

RESULTS

There were 6 statistically significant DEMs between different grades of PNENs. MiR1285-5p was the sole miRNA differentially expressed (p=0.03) between G1 and G2 PNETs. Six statistically significant DEMs (miR135a-5p, miR200a-3p, miR3151-5p, miR-345-5p, miR548d-5p and miR9-5p) (p<0.05) were identified between G1 PNETs and G3 PNENs. Finally, 5 DEMs (miR155-5p, miR15b-5p, miR222-3p, miR548d-5p and miR9-5p) (p<0.05) were identified between G2 PNETs and G3 PNENs.

CONCLUSION

The identified miRNA candidates are concordant with their patterns of dysregulation in other tumour types. The reliability of these DEMs as discriminators of PNEN grades support further investigations using larger patient populations.

Clinical impact of bile-derived exosomal microRNAs as novel diagnostic and prognostic biomarkers for biliary tract cancers

Sampling of bile juice during endoscopic retrograde cholangiopancreatography (ERCP) has potential benefit of being amenable to the identification of novel biomarkers in liquid biopsy. This study reports the results of a global investigation of exosomal microRNAs (miRNAs) in bile to identify potential biomarkers for biliary tract cancers (BTCs). Eighty-eight bile samples collected during ERCP (45 BTC and 43 noncancer control samples) were enrolled in this study. Eleven BTC samples and nine control samples were assigned as the discovery set. Exosomes in bile and serum samples were collected using a glass membrane column with size-controlled macroporous glass (MPG), and exosomal miRNA expression profiles were evaluated using comprehensive miRNA microarray analysis (3D-Gene). For validation, exosomal miRNA in the bile samples of 34 BTCs and 34 controls were comprehensively evaluated using 3D-Gene. In the discovery set, eight exosomal miRNAs in bile were identified as significant aberrant expression markers, while no miRNA with aberrant expression in serum was identified. In a comparison of the discovery and validation sets, miR-451a and miR-3619-3p were identified as reproducible upregulated markers, and the combination of the two bile miRNAs showed an excellent area under the curve (0.819) value for diagnosing BTCs. In addition, high miR-3619-3p expression in bile reflects poorer prognosis of BTCs (hazard ratio = 2.89). The MPG-extracted exosomal miRNAs in bile aspirated during ERCP provide a convenient new approach for diagnosing biliary diseases. Bile-derived miRNA analysis with miR-451a and miR-3619-3p represents a potentially valuable diagnostic strategy for identifying BTCs as well as a predictive indicator of BTC prognosis.

TRPM2-AS promotes the malignancy of osteosarcoma cells by targeting miR-15b-5p/PPM1D axis

Osteosarcoma (OS) is a malignant tumor with a low survival rate and a high incidence rate worldwide. Although research has reported the involvement of long non-coding RNAs (lncRNAs) in the pathogenesis of OS cells, the role of TRPM2-AS, miR-15b-5p, and PPM1D in OS progression remains unclear. This study aimed to examine the interaction of the TRPM2-AS/miR-15b-5p/PPM1D axis in OS cells to gain new insights into the molecular mechanism and pathogenesis of OS. After performing in vitro functional assays, we discovered that TRPM2-AS was overexpressed in OS cells. TRPM2-AS silencing impaired OS cell viability, proliferation, and migration, while it induced apoptosis in OS cells in vitro. Our experimental analysis also revealed that PPM1D is a direct target of miR-15b-5p. TRPM2-AS silencing was found to reverse the tumorigenic effect of the miR-15b-5p inhibitor, while the miR-15b-5p inhibitor restored the inhibition of OS caused by silencing PPM1D. Moreover, our findings revealed that miR-15b-5p exerted its tumor-suppressive role by directly targeting PPM1D. In conclusion, this study suggests that TRPM2-AS could promote OS cell malignancy by sponging miR-15b-5p/PPM1D axis.

Non-Coding RNAs in Normal B-Cell Development and in Mantle Cell Lymphoma: From Molecular Mechanism to Biomarker and Therapeutic Agent Potential

B-lymphocytes are essential for an efficient immune response against a variety of pathogens. A large fraction of hematologic malignancies are of B-cell origin, suggesting that the development and activation of B cells must be tightly regulated. In recent years, differentially expressed non-coding RNAs have been identified in mantle cell lymphoma (MCL) tumor samples as opposed to their naive, normal B-cell compartment. These aberrantly expressed molecules, specifically microRNAs (miRNAs), circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs), have a role in cellular growth and survival pathways in various biological models. Here, we provide an overview of current knowledge on the role of non-coding RNAs and their relevant targets in B-cell development, activation and malignant transformation, summarizing the current understanding of the role of aberrant expression of non-coding RNAs in MCL pathobiology with perspectives for clinical use.

Identification of miRNA-34a and miRNA-155 as prognostic markers for mantle cell lymphoma

Objective

MicroRNAs (miRNAs) with functional relevance have not been previously identified in mantle cell lymphoma (MCL). Here, we aimed to evaluate the relationships between miR-34a and miR-155-5p and MCL clinicopathology and prognosis.

Methods

Seventy-five paraffin-embedded tissue samples from patients with MCL who completed at least four cycles of chemotherapy from January 2006 to October 2016, and 27 samples from control patients with reactive lymphoid hyperplasia (RLH), were collected. MiRNA expression levels were measured by qRT-PCR.

Results

The miR-155-5p levels were significantly higher in patients with MCL than in the controls. The Eastern Cooperative Oncology Group (ECOG) ≥ 2 and Sex-Determining Region Y-Box transcription factor 11 (SOX11) < median value (M) groups presented lower miR-34a expression than the ECOG < 2 and SOX11 ≥ M groups, respectively. MiR-155-5p expression differed between low, intermediate, and high MCL International Prognostic Index risk groups. The AUCs of miR-34a and miR-155-5p were 0.5819 and 0.7784, respectively. The median survival times of the miR-34a ≤ 0.2150 and miR-155-5p > 2.11 groups were shorter than those of the miR-34a > 0.2150 and miR-155-5p ≤ 2.11 groups, respectively.

Conclusions

Low miR-34a and elevated miR-155-5p levels may be correlated with poor prognosis in MCL.

Genomic profiles and clinical outcomes of de novo blastoid/pleomorphic MCL are distinct from those of transformed MCL

Blastoid and pleomorphic mantle cell lymphomas (MCLs) are variants of aggressive histology MCL (AH-MCL). AH-MCL can arise de novo (AH-DN) or transform from prior classic variant MCL (AH-t). This study is the first integrated analysis of clinical and genomic characteristics of AH-MCL. Patient characteristics were collected from diagnosis (AH-DN) and at transformation (AH-t). Survival after initial diagnosis (AH-DN) and after transformation (AH-t) was calculated. Regression tree analysis was performed to evaluate prognostic variables and in univariate and multivariate analyses for survival. Whole-exome sequencing was performed in evaluable biopsy specimens. We identified 183 patients with AH-MCL (108 were AH-DN, and 75 were AH-t; 152 were blastoid, and 31 were pleomorphic). Median survival was 33 months (48 and 14 months for AH-DN and AH-t, respectively; P = .001). Factors associated with inferior survival were age (≥72 years), AH-t category, Ki-67 ≥50% and poor performance status. AH-t had a significantly higher degree of aneuploidy compared with AH-DN. Transformed MCL patients exhibited KMT2B mutations. AH-MCL patients with Ki-67 ≥50% had exclusive mutations in CCND1, NOTCH1, TP53, SPEN, SMARCA4, RANBP2, KMT2C, NOTCH2, NOTCH3, and NSD2 compared with low Ki-67 (<50%). AH-t patients have poor outcomes and distinct genomic profile. This is the first study to report that AH-MCL patients with high Ki-67 (≥50%) exhibit a distinct mutation profile and very poor survival.

Non-coding RNAs (miRNAs and lncRNAs) and their roles in lymphogenesis in all types of lymphomas and lymphoid malignancies

Contemporary developments in molecular biology have been combined with discoveries on the analysis of the role of all non-coding RNAs (ncRNAs) in human diseases, particularly in cancer, by examining their roles in cells. Currently, included among these common types of cancer, are all the lymphomas and lymphoid malignancies, which represent a diverse group of neoplasms and malignant disorders. Initial data suggest that non-coding RNAs, particularly long ncRNAs (lncRNAs), play key roles in oncogenesis and that lncRNA-mediated biology is an important key pathway to cancer progression. Other non-coding RNAs, termed microRNAs (miRNAs or miRs), are very promising cancer molecular biomarkers. They can be detected in tissues, cell lines, biopsy material and all biological fluids, such as blood. With the number of well-characterized cancer-related lncRNAs and miRNAs increasing, the study of the roles of non-coding RNAs in cancer is bringing forth new hypotheses of the biology of cancerous cells. For the first time, to the best of our knowledge, the present review provides an up-to-date summary of the recent literature referring to all diagnosed ncRNAs that mediate the pathogenesis of all types of lymphomas and lymphoid malignancies.

Diagnosis and treatment of lymphomas in the era of epigenetics

Lymphomas represent a heterogeneous group of cancers characterized by clonal lymphoproliferation. Over the past decades, frequent epigenetic dysregulations have been identified in hematologic malignancies including lymphomas. Many of these impairments occur in genes with established roles and well-known functions in the regulation and maintenance of the epigenome. In hematopoietic cells, these dysfunctions can result in abnormal DNA methylation, erroneous chromatin state and/or altered miRNA expression, affecting many different cellular functions. Nowadays, it is evident that epigenetic dysregulations in lymphoid neoplasms are mainly caused by genetic alterations in genes encoding for enzymes responsible for histone or chromatin modifications. We summarize herein the recent epigenetic modifiers findings in lymphomas. We focus also on the most commonly mutated epigenetic regulators and emphasize on actual epigenetic therapies.

miR-100 inhibits cell proliferation in mantle cell lymphoma by targeting mTOR

Background

miR-100 is reported to be associated with cell proliferation and apoptosis. However, the function of miR-100 in mantle cell lymphoma (MCL) is unknown. The purpose of this study is to analyze the abnormal expression of miR-100 and mTOR in MCL together with their potential biological function and pathogenesis.

Method

Eighteen MCL tissue samples and 3 cell lines (Jeko-1, Mino, Granta-519) were investigated in this research study, while eighteen samples of proliferative lymphadenitis from patients and peripheral lymphocyte cells from healthy volunteers served as controls. The expression and alteration of miR-100 and mTOR mRNA were detected by RT-PCR. The expression and alteration of mTOR protein were explored by Western blot. LV-miR-100-up and LV-mTOR-RNAi were constructed and transfected by lentivirus transfection. Cell proliferation, cell apoptosis and the cell cycle were detected using CCK-8 and flow cytometry. Bioinformatics prediction software was used to predict the miR-100 target gene of mTOR. A double luciferase experiment was used to verify miR-100 targeting at the mTOR-3′-UTR. The interaction between miR-100 and mTOR was further studied using recovery experiments. GraphPad Prism 7 software (version 7.2) was used for statistical analysis, and a P value < 0.05 was considered statistically significant.

Results

We found that the expression of miR-100 mRNA in MCL tissues and cell lines was lower, while that of the mTOR protein was higher. There was a negative correlation between miR-100 and mTOR in both MCL tissues and cell lines. Promoting miR-100 and inhibiting mTOR could inhibit cell proliferation, induce cell apoptosis and block the cell cycle in the G1 phase. A double luciferase reporter assay showed that mTOR was one of the target genes of miR-100. The recovery experiment demonstrated that PV-mTOR-up partially set off the effect of LV-miR-100-up on decreasing mTOR expression, inhibiting proliferation, inducing apoptosis and blocking the cell cycle in G1 phase in both Jeko-1 and Mino cells.

Conclusions

Abnormal expression of miR-100 and mTOR was found in MCL, which included downregulation of miR-100 and upregulation of mTOR. The expression of mTOR is negatively correlated with miR-100. It may play an important role in MCL pathogenesis. miR-100 up-regulation can inhibit cell proliferation, promote cell apoptosis, and inhibit cell cycle in G1 phase by targeting the mTOR gene. miR-100 may potentially be an anti-mantle cell lymphoma gene.

Blastoid Mantle Cell Lymphoma

Blastoid and pleomorphic mantle cell lymphoma (MCL) are among the worst prognostic, aggressive histology, high-risk variants of MCL, and, in this article, they are presented as blastoid MCL. Blastoid MCL have not been systematically studied, probably due to their rarity. De novo blastoid MCLs have superior outcomes compared with transformed MCL. Compared with classic MCL, extranodal involvement (mainly skin, central nervous system), frequent relapses, and inferior responses to conventional chemoimmunotherapy, BTK inhibitors and venetoclax are frequent in blastoid MCL. KTE-X19 induces excellent response in blastoid MCL. Combinations with novel agents are actively investigated. This article presents a comprehensive review on blastoid MCL in 2020.

Protocols for the Analysis of microRNA Expression, Biogenesis, and Function in Immune Cells

MicroRNAs (miRNAs) are short (19- to 25-nucleotide) noncoding RNA molecules that target mRNAs to repress gene expression and that play important roles in regulating many fundamental biological functions including cell differentiation, development, growth, and metabolism. They are well conserved in eukaryotic cells and are considered essential ancient elements of gene regulation. miRNA genes are transcribed by RNA polymerase II to generate primary miRNAs (pri-miRNAs), which are cleaved by microprocessor complex in the nucleus to generate stem-loop structures known as pre-miRNAs. Pre-miRNAs are translocated to the cytoplasm and cleaved by Dicer to form the mature miRNAs, which mediate mRNA degradation through their loading to the RNA-induced silencing complex (RISC) and binding to complementary sequences within target mRNAs to repress their translation by mRNA degradation and/or translation inhibition. Because ∼1900 miRNA genes are reported in the human genome, many associated with disease, appropriate methods to study miRNA expression and regulation under physiological and pathological conditions have become increasingly important to the study of many aspects of human biology, including immune regulation. As with small interfering RNA (siRNA), the mechanism of miRNA-mediated targeting has been used to develop miRNA-based therapeutics. For a complete and systematic analysis, it is critical to utilize a variety of different tools to analyze the expression of pri-mRNAs, pre-miRNAs, and mature miRNAs and characterize their targets both in vitro and in vivo. Such studies will facilitate future novel drug design and development. This unit provides six basic protocols for miRNA analysis, covering next-generation sequencing, quantitative real-time PCR (qRT-PCR), and digoxigenin-based expression analysis of pri-mRNAs, pre-miRNAs, and mature miRNAs; mapping of pri-miRNA and their cleavage sites by rapid amplification of cDNA ends (RACE); electrophoretic mobility shift assays (EMSAs) or biotin-based nonradioactive detection of miRNA-protein complexes (miRNPs); and functional analysis of miRNAs using miRNA mimics and inhibitors. © 2019 by John Wiley & Sons, Inc.

An Uncommon Case of Double-Hit Mantle Cell Lymphoma That Demonstrates a Transformation Process

OBJECTIVES

Mantle cell lymphoma (MCL) is a mature B-cell lymphoma characterized by CCND1/IGH rearrangement. We reported a case of MCL harboring both CCND1/IGH and MYC/IGH rearrangements that also presented with an aggressive clinical course.

METHODS

Biopsy specimens were evaluated by morphological staining, immunohistochemistry, flow cytometry, conventional cytogenetics, fluorescence in situ hybridization (FISH), and next-generation sequencing (NGS).

RESULTS

Morphological and immunohistochemical staining of gallbladder samples demonstrated blastoid variant MCL. However, in the bone marrow sample, FISH indicated rearrangements in CCND1/IGH and MYC/IGH. Flow cytometry identified two groups of malignant lymphocytes. We sorted these two groups of cells. NGS then revealed that both cell types carried CCND1/IGH rearrangements and TP53 mutations. Furthermore, the CD19+/CD10+ cells carried additional MYC/IGH rearrangement and NOTCH2 mutation.

CONCLUSIONS

The rearrangement of MYC and a mutation in NOTCH2 probably induced the transformation of MCL cells in this patient. This uncommon double-hit MCL case clearly demonstrates a transformation process.

Long Non-Coding RNAs Modulate Sjögren's Syndrome Associated Gene Expression and Are Involved in the Pathogenesis of the Disease

Primary Sjögren's syndrome (pSjS) is a chronic systemic autoimmune disorder, primarily affecting exocrine glands; its pathogenesis is still unclear. Long non-coding RNAs (lncRNAs) are thought to play a role in the pathogenesis of autoimmune diseases and a comprehensive analysis of lncRNAs expression in pSjS is still lacking. To this aim, the expression of more than 540,000 human transcripts, including those ascribed to more than 50,000 lncRNAs is profiled at the same time, in a cohort of 16 peripheral blood mononuclear cells PBMCs samples (eight pSjS and eight healthy subjects). A complex network analysis is carried out on the global set of molecular interactions among modulated genes and lncRNAs, leading to the identification of reliable lncRNA-miRNA-gene functional interactions. Taking this approach, a few lncRNAs are identified as targeting highly connected genes in the pSjS transcriptome, since they have a major impact on gene modulation in the disease. Such genes are involved in biological processes and molecular pathways crucial in the pathogenesis of pSjS, including immune response, B cell development and function, inflammation, apoptosis, type I and gamma interferon, epithelial cell adhesion and polarization. The identification of deregulated lncRNAs that modulate genes involved in the typical features of the disease provides insight in disease pathogenesis and opens avenues for the design of novel therapeutic strategies.

MicroRNAs as Biomarkers of B-cell Lymphoma

B-cell lymphomas represent a diverse group of neoplasms classified primarily by histopatholgy and are often challenging to accurately diagnose. Despite having been recognized less than 20 years ago, microRNAs (miRNAs) have emerged as one of the most promising class of cancer molecular biomarkers and are particularly attractive as they can be readily detected in formalin-fixed paraffin-embedded biopsy material and biological fluids such as blood. Many of the identified B-cell lymphoma miRNA biomarkers also play crucial regulatory roles in normal B-cell development. Below we consider the identity, function, and biomarker potential of miRNAs in B-cell lymphoma and most importantly the barriers that remain to be overcome if they are really to become part of routine clinical practice.

Abnormal microRNA expression in the course of hematological malignancies

Research on the carcinogenesis process is currently focused primarily on understanding its genetic basis and molecular abnormalities that may be predictive factors and therapeutic targets. It was clearly confirmed recently that microRNAs are involved in the mechanisms of leukocyte development, differentiation, and apoptosis, as well as in the pathogenesis of proliferative diseases of the hematopoietic system. Currently, research strategies allow determination of the deregulation of microRNA profiles in relation to other cytogenetic aberrations, as well as prognostic factors and primary end points. The problem of the possibility of their use as therapeutic targets is also increasingly discussed. In this article, we analyze literature data on abnormalities in microRNA expression in proliferative diseases of the hematopoietic system in the context of classic cytogenetic and molecular aberrations.

miR-15b-5p facilitates the tumorigenicity by targeting RECK and predicts tumour recurrence in prostate cancer

MicroRNAs (miRNAs) have been reported to participate in many biological behaviours of multiple malignancies. Recent studies have shown that miR‐15b‐5p (miR‐15b) exhibits dual roles by accelerating or blocking tumour progression. However, the molecular mechanisms by which miR‐15b contributes to prostate cancer (PCa) are still elusive. Here, miR‐15b expression was found significantly up‐regulated in PCa in comparison with the normal samples and was positively correlated with age and Gleason score in patients with PCa. Notably, PCa patients with miR‐15b high expression displayed a higher recurrence rate than those with miR‐15b low expression (P = 0.0058). Knockdown of miR‐15b suppressed cell growth and invasiveness in 22RV1 and PC3 cells, while overexpression of miR‐15b reversed these effects. Then, we validated that RECK acted as a direct target of miR‐15b by dual‐luciferase assay and revealed the negative correlation of RECK with miR‐15b expression in PCa tissues. Ectopic expression of RECK reduced cell proliferation and invasive potential and partially abrogated the tumour‐promoting effects caused by miR‐15b overexpression. Additionally, miR‐15b knockdown inhibited tumour growth activity in a mouse PCa xenograft model. Taken together, our findings indicate that miR‐15b promotes the progression of PCa cells by targeting RECK and represents a potential marker for patients with PCa.

miR-15b represses BACE1 expression in sporadic Alzheimer's disease

Beta-site Amyloid precursor protein Cleaving Enzyme 1 (BACE1) is conceived as a potential target for therapies against Alzheimer disease (AD). MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression in a sequence-specific manner. Although miRNAs have been increasingly recognized as important modulators in sporadic AD. In order to confirm whether miR-15b correlates with the BACE1 upregulation in sporadic AD, we firstly evaluated the expression of miR-15b and BACE1 in sporadic AD brain tissues and analyzed the correlation of miR-15b with BACE1. Then we determined the regulation of miR-15b in SH-SY5Y cells on the BACE1 expression. And finally we determined the targeting to 3’ UTR of BACE1 by miR-15b by a luciferase reporter. Downregulation of miR-15b alleviated Aβ-induced viability inhibition and decreased apoptosis in SH-SY5Y cells. Our results demonstrated that miR-15b play an important role in the cellular AD phenotype and might be involved in the pathogenesis of AD.

Increased expression of miR-15b is associated with clinicopathological features and poor prognosis in cervical carcinoma

OBJECTIVE

The aims of this study were to explore the expression of microRNA-15b (miR-15b) in cervical carcinoma and to correlate its expression with clinicopathological characteristics and prognosis.

METHODS

Quantitative reverse transcriptase polymerase chain reaction analysis was conducted to quantify the expression level of miR-15b in 607 cervical tissues, including 185 cervical carcinoma tissues, 124 CIN I lesions, 148 CIN II-III lesions, and 150 normal cervical tissues. The 5-year overall cumulative survival rates for all patients with cervical carcinoma were calculated using Kaplan-Meier survival analysis, and multivariate survival analysis of these patients was completed using the stepwise Cox proportional hazards regression model.

RESULTS

The expression of miR-15b gradually increased from normal cervical tissues to CIN lesions and then to cervical carcinoma tissues (all P < 0.05), and it was strongly correlated with degree of differentiation, clinical stage, tumor diameter, and lymph-node metastases (all P < 0.05). When the median value of miR-15b expression was used as the cut-off point, patients with high miR-15b expression (above the median) had worse 5-year overall cumulative survival rates than those who exhibited low miR-15b expression (below the median; P < 0.05). Multivariate analysis using the Cox regression model identified miR-15b expression, clinical stage, tumor diameter, and lymph-node metastasis as independent risk factors for cervical carcinoma prognosis (all P < 0.05).

CONCLUSION

Our results indicate that elevated miRNA-15b expression is a typical feature in cervical carcinoma, which could be a useful clinical predictor for the early diagnosis and evaluation of cervical carcinoma prognosis.

Diagnostic and therapeutic update of mantle cell lymphoma (MCL): analysis of seven cases treated in a centre in one year

Mantle cell lymphoma (MCL) is an infrequent subtype of non-Hodgkin's lymphoma (NHL) and represents between 4-8% of adult lymphomas. Recently an increase in its incidence to 1-2 cases/100,000 inhabitants/year has been observed. The first line of treatment is based on chemoimmunotherapy and depends on age and the initial stage at diagnosis. There are no second line or successive treatments. There are currently several drugs available that provide acceptable results.