MicroRNA-92a-3p overexpression in peripheral blood mononuclear cells is an independent predictor of prolonged overall survival of patients with chronic lymphocytic leukemia

miRNA Biology in Chronic Lymphocytic Leukemia

microRNAs (miRNAs) are a class of small non-coding RNAs that play a crucial regulatory role in fundamental biological processes and have been implicated in various diseases, including cancer. The first evidence of the cancer-related function of miRNAs was discovered in chronic lymphocytic leukemia (CLL) in the early 2000s. Alterations in miRNA expression have since been shown to strongly influence the clinical course, prognosis, and response to treatment in patients with CLL. Therefore, the identification of specific miRNA alterations not only enhances our understanding of the molecular mechanisms underlying CLL but also holds promise for the development of novel diagnostic and therapeutic strategies. This review aims to provide a comprehensive summary of the current knowledge and recent insights into miRNA dysregulation in CLL, emphasizing its pivotal roles in disease progression, including the development of the lethal Richter syndrome, and to provide an update on the latest translational research in this field.

Deregulation of miR-1245b-5p and miR-92a-3p and their potential target gene, GATA3, in epithelial-mesenchymal transition pathway in breast cancer

BACKGROUND

MicroRNAs (miRNAs) are small molecules that have prominent roles in tumor development and metastasis and can be used for diagnostic and therapeutic purposes. This study evaluated the expression of miR-92a-3p and miR-1245b-5p and their potential target gene, GATA3 in patients with breast cancer (BC).

MATERIALS AND METHODS

In the search for BC-related microRNAs, miR-124b-5p and miR-92a-3p were selected using Medline through PubMed, miR2disease, miRcancer and miRTarBase. Moreover, target gene GATA3 and their possible interaction in the regulating epithelial-mesenchymal transition (EMT) and invasion was evaluated using in silico tools including miRTarBase, TargetScan, STRING-db, and Cytoscape. The expression level of miR-92a-3p, miR1245b-5p, and GATA3 were assessed on extracted RNAs of tumor and nontumor tissues from 36 patients with BC using qPCR. Additionally, clinical-pathologic characteristics, such as tumor grade, tumor stage, lymph node were taken into consideration and the diagnostic power of these miRNAs and GATA3 was evaluated using the ROC curve analysis.

RESULTS

In silico evaluation of miR-92a-3p and miR-1245b-5p supports their potential association with EMT and invasion signaling pathways in BC pathogenesis. Comparing tumor tissues to nontumor tissues, we found a significant downregulation of miR-1245b-5p and miR-92a-3p and upregulation of GATA3. Patients with BC who had decreased miR-92a-3p expression also had higher rates of advanced stage/grade and ER expression, whereas decreased miR-1245b-5p expression was only linked to ER expression and was not associated with lymph node metastasis. The AUC of miR-1245b-5p, miR-92a-3p, and GATA3 using ROC curve was determined 0.6449 (p = .0239), 0.5980 (p = .1526), and 0.7415 (p < .0001), respectively, which showed a significant diagnostic accuracy of miR-1245b-5p and GATA3 between the BC patients and healthy individuals.

CONCLUSION

MiR-1245b-5p, miR-92a-3p, and GATA3 gene contribute to BC pathogenesis and they may be having potential regulatory roles in signaling pathways involved in invasion and EMT pathways in BC pathogenesis, as a result of these findings. More research is needed to determine the regulatory mechanisms that they control.

Effect of mir-92a-3p on hydroquinone induced changes in human lymphoblastoid cell cycle and apoptosis

Hydroquinone (HQ), one of the metabolites of benzene in humans, has significant hepatotoxic properties. Chronic exposure to HQ can lead to leukemia. In a previous study by this group, we constructed a model of malignant transformation of human lymphoblastoid cells (TK6) induced by chronic exposure to HQ with significant subcutaneous tumorigenic capacity in nude mice. miR-92a-3p is a tumor factor whose role in HQ-induced malignant transformation is not yet clear. In the present study, raw signal analysis and dual-luciferase reporter gene results suggested that miR-92a-3p could target and regulate TOB1, and the expression level of miR-92a-3p was significantly upregulated in the long-term HQ-induced TK6 malignant transformation model, while the anti-proliferative factor TOB1 was significantly downregulated. To investigate the mechanism behind this, we inhibited miR-92a-3p in a malignant transformation model and found a decrease in cell viability, a decrease in MMP-9 protein levels, a G2/M phase block in the cell cycle, and an upregulation of the expression of G2/M phase-related proteins cyclinB1 and CDK1. Inhibition of miR-92a-3p in combination with si-TOB1 restored cell viability, inhibited cyclin B1 and CDK1 protein levels, and attenuated the G2/M phase block. Taken together, miR-92a-3p reduced the cell proliferation rate of HQ19 and caused cell cycle arrest by targeting TOB1, which in turn contributed to the altered malignant phenotype of the cells. This study suggests that miR-92a-3p is likely to be a biomarker for long-term HQ-induced malignant transformation of TK6 and could be a potential therapeutic target for leukemia caused by long-term exposure to HQ.

Prognostic Value of the miR-17~92 Cluster in Chronic Lymphocytic Leukemia

The aim of this study was to investigate the expression of miR-17∼92 cluster members in chronic lymphocytic leukemia (CLL) patients. Six microRNAs (miRNAs)-miR-17, miR-18a, miR-19a, miR-19b-1, miR-20a, and miR-92a-1-very poorly characterized in CLL patients, were chosen for the study to consider their possible role as cancer biomarkers. It is currently unclear to which extent miR-17~92 expression is related to other routinely measured CLL markers, and whether the findings can be of any clinical significance. To achieve this goal, we report the expression levels of these miRNAs detected by RT-qPCR in purified CD19+ B lymphocytes of 107 CLL patients and correlate them with existing clinical data. The study provides new evidence regarding the heterogeneity of miR-17~92 cluster members' expression in CLL patients. Higher miR-17-5p expression was associated with unfavorable prognostic factors (i.e., 17p and 11q deletions, CD38 and ZAP-70 expression). On the other hand, miR-19a, miR-20a, and miR-92a-1 negatively correlated with these adverse factors. The presence of del(13q) as a sole aberration was associated with a significantly lower miR-17-5p as well as higher miR-19a-3p and miR-92a-1-5p expression compared to patients carrying unfavorable genetic aberrations. Particularly, miR-20a could be considered an independent favorable prognostic factor. In a multivariate analysis, high miR-20a expression remained an independent marker predicting long TTT (time to treatment) for CLL patients.

miRNA profile at diagnosis predicts treatment outcome in patients with B-chronic lymphocytic leukemia: A FILO study

During many years, chemo-immunotherapy fludarabine-cyclophosphamide-rituximab (FCR) was the gold standard for first line treatment of medically fit patients with symptomatic B-chronic lymphocytic leukemia (CLL). Over the last decade, targeted biotherapies have revolutionized the treatment of B-CLL patients and almost entirely supplanted FCR. However, no biomarker still exists to predict the complete remission (CR) with undetectable minimal residual disease (uMRD) in bone marrow (BM), which remains the best predictive factor for survival. MicroRNAs represent a class of molecular biomarkers which expression is altered in B-CLL. Our study aimed at identifying before treatment blood miRNAs that predict treatment outcome in previously untreated B-CLL patients (NCT 01370772, https://clinicaltrials.gov/ct2/show/NCT01370772). Using hierarchical clustering of miRNA expression profiles discriminating 8 patients who achieved CR with BM uMRD from 8 patients who did not achieve CR and displayed detectable BM MRD, we identified 25 miRNAs differentially expressed before treatment. The expression of 11 miRNAs was further validated on a larger cohort (n=123). Based on the dosage of 5 miRNAs at diagnosis, a decision tree was constructed to predict treatment outcome. We identified 6 groups of patients with a distinct probability of being CR with BM uMRD to FCR treatment, ranging from 72% (miR-125b, miR-15b and miR-181c high) to 4% (miR-125b and miR-193b low). None of the patients displaying high expression levels of miR-125b, miR-15b and miR-181c relapsed during study follow-up. In contrast, patients with low miR-15b and high miR-412, or with low miR-125b and miR-193b, demonstrated significant low PFS. RNA sequencing of blood at diagnosis identified that patients relapsing after treatment are characterized by significant enrichment of gene signatures related to cell cycle, MYC target genes, metabolism and translation regulation. Conversely, patients achieving CR with BM uMRD displayed significant enrichment in genes related to communication between CLL cells and the microenvironment, immune system activation and upregulation of polycomb PRC2 complex target genes. Our results suggest that blood miRNAs are potent predictive biomarkers for FCR treatment efficacy and might be implicated in the FCR efficacy in B-CLL patients, providing new insight into unmet need for the treatment of B-CLL patients and identifying pathways predictive of patients’ remission.

Expression of miR-92a is associated with the prognosis in non-small cell lung cancer: An observation study

With the development of molecular biology technology, the discovery of microRNAs (miRNAs) has provided new ideas for the diagnosis, treatment, and prognosis of lung cancer and laid a foundation for the study of this malignancy. To assess the potential prognostic value of miR-92a as a new biomarker in non-small cell lung cancer (NSCLC) via clinical evaluation, a total of 100 patients with NSCLC admitted to the Respiratory and Intensive Care Department of Suining Central Hospital in Sichuan Province between August 2007 and April 2020 were retrospectively analyzed. The correlation between miR-92a expression and prognosis of patients with NSCLC was also evaluated in the present study. The expression level of miR-92a was measured by PT-PCR and in situ hybridization. Chi-square test was adopted to explore the relationship of miR-92a expression and clinical features. Kaplan-Meier survival curves were plotted to delineate the overall survival rate of patients with NSCLC. Cox regression analysis was performed to evaluate the prognostic significance of miR-92a expression in NSCLC. The miR-92a expression in NSCLC tissue samples was significantly higher than that in normal lung tissues (P < .001) and significantly correlated with the Eastern Cooperative Oncology Group score, histological type, and distant metastasis (P < .05). Survival curve revealed that patients with NSCLC and high miR-92a expression had relatively higher mortality than those with low PAK4 expression (P = .001). Cox regression analysis explained that miR-92a expression was associated with the prognosis of patients with NSCLC (HR = 1.8, 95% CI: 1.0-3.2, P = .036). In summary, miR-92a was highly expressed in NSCLC tissues and could act as a prognostic factor for patients with NSCLC. These results illustrate that miR-92a expression plays an important role in the invasion and metastasis of NSCLC, and miR-92a can be used as a new biomarker to determine the prognosis of this cancer.

Prognostic significance of microRNA 17-92 cluster expression in Egyptian chronic lymphocytic leukemia patients

BACKGROUND

Abnormal expression patterns of microRNAs (miRs) play an important role in the development and progression of malignancy. Identification of the clinical significance and prognostic value of these small molecules in chronic lymphocytic leukemia (CLL); a disease of heterogeneous biological landscape and clinical course, has always been of tremendous translational value.

AIM

To evaluate the prognostic value of microRNA17-92 cluster members in Egyptian CLL patients.

METHODS

The expression levels of miR17-92 cluster members were evaluated by qRT-PCR, including miR17, miR18a, miR19a, miR19b-1, miR20a, and miR92a-1. Other investigations included serum LDH, serum β2 microglobulin (β2M), CD38 and ZAP70 expression by flow cytometry, fluorescence in situ hybridization (FISH) for 17p deletion, and imaging studies (computerized tomography (CT) scans of neck, chest, abdomen, and pelvis or PET-CT scans).

RESULTS

Overexpression of all members of the miRNA17-92 cluster was detected in CLL patients compared to controls (p =  < 0.001 for all miRs while p = 0.01 for miR19b-1). A significant positive correlation between Hb and miR17 and a significant negative correlation between Hb and miR19b-1 were observed (p = 0.041, 0.017 respectively). A statistically significant positive correlation between miR19b-1 expression and each of the WBCs and absolute lymphocytic count (ALC) was detected (p = 0.023, 0.022 respectively). Moreover, a statistically significant relation between miR19b-1 expression and advanced Binet stages was also found (p = 0.05). Regarding miR18a, a statistically significant positive correlation with LDH level was found (p = 0.003). We also found a significant positive correlation between miR92a-1 and β2M level (p = 0.005), as well as a significant relation between miR17 and negative CD38 expression (p = 0.034). However, no significant relationships between any of studied miRNA expression levels and 17p deletion or response to treatment were observed. Patients who expressed miR19b-1 were significantly indicated to start therapy at diagnosis (p = 0.05). The overall survival of CLL patients included in our study was 90.2% after 1 year from the time of diagnosis. Patients with high expression of miR19a had better OS than those with low expression (p = 0.04).

CONCLUSIONS

Overexpression of all members of the miR17-92 cluster was detected in Egyptian CLL patients. MiR18a, miR19b-1, and miR92a-1 also have an adverse prognostic value while miR17 can be considered a good prognostic marker. High expression of miR19a is associated with better OS.

A 3' tRNA-derived fragment produced by tRNALeuAAG and tRNALeuTAG is associated with poor prognosis in B-cell chronic lymphocytic leukemia, independently of classical prognostic factors

OBJECTIVE

3' tRNA-derived fragments (3' tRFs) are important epigenetic regulators in normal and pathological conditions. In this study, we aimed to explore the potential value of a 3' tRF as a prognostic and/or screening biomarker for B-cell chronic lymphocytic leukemia (B-CLL).

METHODS

Publicly available next-generation sequencing data from 20 B-CLL cases were analyzed, followed by prediction of targets of the most abundantly and ubiquitously expressed 3' tRFs, leading to selection of tRF-Leu^AAG/TAG . PBMCs were isolated from blood samples of 91 B-CLL patients and 43 non-leukemic donors, followed by total RNA extraction, in-vitro polyadenylation, and first-strand cDNA synthesis. Next, a real-time quantitative PCR (qPCR) assay was developed for the accurate quantification of tRF-Leu^AAG/TAG and applied in all samples, prior to biostatistical analysis.

RESULTS

High tRF-Leu^AAG/TAG levels are associated with inferior overall survival (OS) of B-CLL patients. The unfavorable significance of tRF-Leu^AAG/TAG was independent of established prognostic factors in B-CLL. Stratified Kaplan-Meier OS analysis uncovered the unfavorable prognostic role of high tRF-Leu^AAG/TAG levels for patients in Binet A or Rai I stage, negative CD38 expression, mutated, or unmutated IGHV genomic locus.

CONCLUSION

Our approach revealed the independent prognostic value of a particular 3' tRF, derived from tRNA^LeuAAG and tRNA^LeuTAG (tRF-Leu^AAG/TAG ) in B-CLL.

Glutaminase isoforms expression switches microRNA levels and oxidative status in glioblastoma cells

Background

Glutaminase isoenzymes GLS and GLS2 play apparently opposing roles in cancer: GLS acts as an oncoprotein, while GLS2 (GAB isoform) has context specific tumour suppressive activity. Some microRNAs (miRNAs) have been implicated in progression of tumours, including gliomas. The aim was to investigate the effect of GLS and GAB expression on both miRNAs and oxidative status in glioblastoma cells.

Methods

Microarray profiling of miRNA was performed in GLS-silenced LN229 and GAB-transfected T98G human glioblastoma cells and their wild-type counterparts. Results were validated by real-time quantitative RT-PCR. Oxidative status and antioxidant enzymes were determined by spectrophotometric or fluorescence assays in GLS-silenced LN229 and T98G, and GAB-transfected LN229 and T98G.

Results

MiRNA-146a-5p, miRNA-140-3p, miRNA-21-5p, miRNA-1260a, and miRNA-92a-3p were downregulated, and miRNA-1246 was upregulated when GLS was knocked down. MiRNA-140-3p, miRNA-1246, miRNA-1260a, miRNA-21-5p, and miRNA-146a-5p were upregulated when GAB was overexpressed. Oxidative status (lipid peroxidation, protein carbonylation, total antioxidant capacity, and glutathione levels), as well as antioxidant enzymes (catalase, superoxide dismutase, and glutathione reductase) of silenced GLS glioblastoma cells and overexpressed GAB glioblastoma cells significantly changed versus their respective control glioblastoma cells. MiRNA-1246, miRNA-1260a, miRNA-146a-5p, and miRNA-21-5p have been characterized as strong biomarkers of glioblastoma proliferation linked to both GLS silencing and GAB overexpression. Total glutathione is a reliable biomarker of glioblastoma oxidative status steadily associated to both GLS silencing and GAB overexpression.

Conclusions

Glutaminase isoenzymes are related to the expression of some miRNAs and may contribute to either tumour progression or suppression through certain miRNA-mediated pathways, proving to be a key tool to switch cancer proliferation and redox status leading to a less malignant phenotype. Accordingly, GLS and GAB expression are especially involved in glutathione-dependent antioxidant defence.

MicroRNAs: Tiny Regulators of Gene Expression with Pivotal Roles in Normal B-Cell Development and B-Cell Chronic Lymphocytic Leukemia

Simple Summary

The involvement of miRNAs in physiological cellular processes has been well documented. The development of B cells, which is dictated by a miRNA-transcription factor regulatory network, suggests a typical process partly orchestrated by miRNAs. Besides their contribution in normal hematopoiesis, miRNAs have been severally reported to be implicated in hematological malignancies, a typical example of which is B-cell chronic lymphocytic leukemia (B-CLL). Numerous studies have attempted to highlight the regulatory role of miRNAs in B-CLL or establish some of them as molecular biomarkers or therapeutic targets. Thus, a critical review summarizing the current knowledge concerning the multifaceted role of miRNAs in normal B-cell development and B-CLL progression, prognosis, and therapy, is urgent. Moreover, this review aims to highlight important miRNAs in both normal B-cell development and B-CLL and discuss future perspectives concerning their regulatory potential and establishment in clinical practice.

Abstract

MicroRNAs (miRNAs) represent a class of small non-coding RNAs bearing regulatory potency. The implication of miRNAs in physiological cellular processes has been well documented so far. A typical process orchestrated by miRNAs is the normal B-cell development. A stage-specific expression pattern of miRNAs has been reported in the developmental procedure, as well as interactions with transcription factors that dictate B-cell development. Besides their involvement in normal hematopoiesis, miRNAs are severally implicated in hematological malignancies, a typical paradigm of which is B-cell chronic lymphocytic leukemia (B-CLL). B-CLL is a highly heterogeneous disease characterized by the accumulation of abnormal B cells in blood, bone marrow, lymph nodes, and spleen. Therefore, timely, specific, and sensitive assessment of the malignancy is vital. Several studies have attempted to highlight the remarkable significance of miRNAs as regulators of gene expression, biomarkers for diagnosis, prognosis, progression, and therapy response prediction, as well as molecules with potential therapeutic utility. This review seeks to outline the linkage between miRNA function in normal and malignant hematopoiesis by demonstrating the main benchmarks of the implication of miRNAs in the regulation of normal B-cell development, and to summarize the key findings about their value as regulators, biomarkers, or therapeutic targets in B-CLL.

Low expression of miR-20b-5p indicates favorable prognosis in laryngeal squamous cell carcinoma, especially in patients with non-infiltrated regional lymph nodes

PURPOSE

Tumor recurrence and distant metastasis are very common in laryngeal squamous cell carcinoma (LSCC). In this study, we examined the potential prognostic value of microRNA-20b-5p (miR-20b-5p), a component of the tumor-related miR-106a/363 cluster.

MATERIALS AND METHODS

Total RNA was purified from 105 tissue specimens resected from patients having undergone surgical treatment for primary LSCC. After in vitro polyadenylation and reverse transcription, a sensitive real-time quantitative polymerase chain reaction (qPCR) methodology was applied for the relative quantification of miR-20b-5p levels. Then, we proceeded with biostatistical analysis, seeking to assess the prognostic value of miR-20b-5p expression in LSCC.

RESULTS

miR-20b-5p positivity constitutes a predictor of inferior DFS and OS in LSCC (P < 0.001 and P = 0.002, respectively). The significant prognostic value of miR-20b-5p expression status seems to be independent of tumor size, histological grade, and TNM stage, as revealed by the multivariate bootstrap Cox regression analysis. Kaplan-Meier survival analysis showed also that miR-20b-5p expression status can stratify LSCC patients with non-infiltrated regional lymph nodes (N0) into two subgroups with distinct prognosis (P = 0.004 and P = 0.004, respectively).

CONCLUSIONS

The miR-20b-5p expression status is a promising molecular tissue biomarker in LSCC, with an independent prognostic value, and thus merits further validation in larger cohorts of patients.

A novel, mitochondrial, internal tRNA-derived RNA fragment possesses clinical utility as a molecular prognostic biomarker in chronic lymphocytic leukemia

OBJECTIVES

Chronic lymphocytic leukemia (CLL) is the most common leukemia among adults. The prognosis of CLL patients varies considerably. Transfer RNA-derived RNA fragments (tRFs) constitute a class of small non-coding RNA fragments excised from mature tRNAs and pre-tRNAs located in nuclei as well as in mitochondria. In this study, the clinical utility of i-tRF-Phe^GAA, a novel mitochondrial tRF, was investigated in CLL.

DESIGN AND METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from 91 CLL patients and 43 non-leukemic controls. Total RNA was isolated from each sample, polyadenylated at the 3' end and reversely transcribed. An in-house developed real-time quantitative PCR assay was developed and applied, and the results were biostatistically analyzed. For the normalization of the i-tRF-Phe^GAA expression levels, the expression of a small nucleolar RNA (RNU48) was used as reference.

RESULTS

Mann-Whitney U test showed that i-tRF-Phe^GAA can distinguish between CLL samples and normal controls (p < 0.001). As determined by Kaplan-Meier survival analysis, overexpression of i-tRF-Phe^GAA was related to poor overall survival of the CLL patients (p < 0.001). Univariate bootstrap Cox regression analysis exhibited a higher hazard ratio of 7.95 (95% CI = 2.37-26.72, p < 0.001) for patients with positive i-tRF-Phe^GAA expression status. Multivariate bootstrap Cox regression analysis showed that the prognostic value of this tRF is independent of clinical stage, mutational status of the immunoglobulin heavy chain variable (IGHV) genetic locus, and CD38 expression status (p = 0.010).

CONCLUSIONS

Our results show that i-tRF-Phe^GAA can serve as a molecular biomarker of poor prognosis in CLL, alongside with the existing factors for CLL prognosis.

Downregulation of circ_0132266 in chronic lymphocytic leukemia promoted cell viability through miR-337-3p/PML axis

Circular RNAs (circRNAs) have recently been reported to play crucial roles in various regulatory processes and involved in cancer onset and progression. However, the potential mechanism of circRNAs in chronic lymphocytic leukemia (CLL) remains largely unknown. Here, we observed hsa_circ_0132266 (circ_0132266), a circRNA significantly decreased in the peripheral blood mononuclear cells (PBMCs) of CLL patients compared with healthy donors, could act as an endogenous sponge of hsa-miR-337-3p (miR-337-3p) and regulate its activity, which resulted in a downstream change of target-gene PML and a consequent influence on cell viability. Taken together, our data indicated the regulatory mechanism of circ_0132266 in CLL progression through circ_0132266/miR-337-3p/PML axis, suggesting that it may serve as a biomarker as well as an exploitable therapeutic target for CLL.

Dietary delphinidin inhibits human colorectal cancer metastasis associating with upregulation of miR-204-3p and suppression of the integrin/FAK axis

Delphinidin is a flavonoid belonging to dietary anthocyanidin family that has been reported to possess diverse anti-tumoral activities. However, the effects of delphinidin on colorectal cancer (CRC) cells and the underlying mechanisms are not fully understood. Thus, we aimed to investigate the anti-cancer activity of delphinidin in CRC cells and the underlying molecular mechanisms. The effects of delphinidin on the viability, metastatic characteristics, signaling, and microRNA (miR) profile of human CRC cell lines used were analyzed. In vivo metastasis was also evaluated using xenograft animal models. Our findings showed that delphinidin (<100 μM) inhibited the colony formation of DLD-1, SW480, and SW620 cells, but non-significantly affected cell viability. Delphinidin also suppressed the migratory ability and invasiveness of the tested CRC cell lines, downregulated integrin αV/β3 expression, inhibited focal adhesion kinase (FAK)/Src/paxillin signaling, and interfered with cytoskeletal construction. Analysis of the miR expression profile revealed a number of miRs, particularly miR-204-3p, that were significantly upregulated and downregulated by delphinidin. Abolishing the expression of one upregulated miR, miR-204-3p, with an antagomir restored delphinidin-mediated inhibition of cell migration and invasiveness in DLD-1 cells as well as the αV/β3-integrin/FAK/Src axis. Delphinidin also inhibited the lung metastasis of DLD-1 cells in the xenograft animal model. Collectively, these results indicate that the migration and invasion of CRC cells are inhibited by delphinidin, and the mechanism may involve the upregulation of miR-204-3p and consequent suppression of the αV/β3-integrin/FAK axis. These findings suggest that delphinidin exerts anti-metastatic effects in CRC cells by inhibiting integrin/FAK signaling and indicate that miR-204-3p may play an important role in CRC metastasis.

Investigation of MiR-92a as a Prognostic Indicator in Cancer Patients: a Meta-Analysis

Background: MiR-92a has been discovered to be involved in the malignant behavior of various types of cancers. However, the particular clinical and prognostic roles of miR-92a in tumors still need to be identified more precisely. The current meta-analysis assessed the prognostic value of miR-92a in various carcinomas.

Methods: Systematic literature searches of PubMed, PMC, Web of Science (WOS), Embase in English and Wanfang, SinoMed and the China National Knowledge Infrastructure (CNKI) in Chinese up to Jan 15^th 2019 were conducted for eligible studies. Twenty studies involving a total of 2573 patients were included in the analysis. Pooled hazard ratios (HR) for overall survival (OS) and disease-free survival (DFS), progression-free survival (PFS) and recurrence-free survival (RFS) were assessed using fixed-effects and random-effects models. Meta-regression and subgroup analyses were carried out to explore the source of heterogeneity. Odds ratio (OR) and 95%CIs were applied to evaluate the relationship between miR-92a expression levels and clinicopathological characteristics.

Results: A significant association between miR-92a levels and OS (HR=2.18) was identified. The random pooling model also revealed significance of consistency (HR=2.14), indicating that the stability of the results. Subgroup analyses were performed and the corresponding significance was recognized in Chinese cancer patients (HR=2.35), studies of specimen derived from tissues (HR=2.43), non-hematological cancer (HR=2.35), osteosarcoma (HR=2.54), non-small cell lung cancer (HR=2.33), hepatocellular carcinoma (HR=2.40) and so on. There were significant relations observed of the expression level of miR-92a to tumor size (≥5 vs <5 cm) (OR=2.13), lymph node metastasis (present vs. absent) (OR=1.87), distant metastasis (present vs. absent) (OR=2.99) and so on.

Conclusions: the over expression of miR-92a is associated with unfavorable prognosis of Chinese cancer patients. In addition, patients of elevated miR-92a expression level are likely to develop the cancers of more malignant behaviors.

miR-17∼92 in lymphocyte development and lymphomagenesis

microRNAs (miRNAs) down-modulate the levels of proteins by sequence-specific binding to their respective target mRNAs, causing translational repression or mRNA degradation. The miR-17∼92 cluster encodes for six miRNAs whose target recognition specificities are determined by their distinct sequence. In mice, the four miRNA families generated from the miR-17∼92 cluster coordinate to allow for proper lymphocyte development and effective adaptive immune responses following infection or immunization. Lymphocyte development and homeostasis rely on tight regulation of PI3K signaling to avoid autoimmunity or immunodeficiency, and the miR-17∼92 miRNAs appear as key mediators to appropriately tune PI3K activity. On the other hand, in lymphoid tumors overexpression of the miR-17∼92 miRNAs is a common oncogenic event. In this review, we touch on what we have learned so far about the miR-17∼92 miRNAs, particularly with respect to their role in lymphocyte development, homeostasis and pathology.

Alternative Splicing Detection Tool-a novel PERL algorithm for sensitive detection of splicing events, based on next-generation sequencing data analysis

Next-generation sequencing (NGS) can provide researchers with high impact information regarding alternative splice variants or transcript identifications. However, the enormous amount of data acquired from NGS platforms make the analysis of alternative splicing events hard to accomplish. For this reason, we designed the "Alternative Splicing Detection Tool" (ASDT), an algorithm that is capable of identifying alternative splicing events, including novel ones from high-throughput NGS data. ASDT is available as a PERL script at http://aias.biol.uoa.gr/~mtheo and can be executed on any system with PERL installed. In addition to the detection of annotated and novel alternative splicing events from high-throughput NGS data, ASDT can also analyze the intronic regions of genes, thus enabling the detection of novel cryptic exons residing in annotated introns, extensions of previously annotated exons, or even intron retentions. Consequently, ASDT demonstrates many innovative and unique features that can efficiently contribute to alternative splicing analysis of NGS data.

Non-coding RNAs: the riddle of the transcriptome and their perspectives in cancer

Non-coding RNAs (ncRNAs) constitute a heterogeneous group of RNA molecules in terms of biogenesis, biological function as well as length and structure. These biological molecules have gained attention recently as a potentially crucial layer of tumor cell progression or regulation. ncRNAs are expressed in a broad spectrum of tumors, and they play an important role not only in maintaining but also in promoting cancer development and progression. Recent discoveries have revealed that ncRNAs may act as key signal transduction mediators in tumor signaling pathways by interacting with RNA or proteins. These results reinforce the hypothesis, that ncRNAs constitute therapeutic targets, and point out their clinical potential as stratification markers. The major purpose of this review is to mention the emergence of the importance of ncRNAs, as molecules which are correlated with cancer, and to discuss their clinical implicit as prognostic diagnostic indicators, biomarkers, and therapeutic targets.