Regulatory mechanism of miR-20a-5p expression in Cancer

Novel epitranscriptomic and epigenetic therapeutic strategies and targets for ferroptosis in liver fibrosis

Liver fibrosis is characterized by an excessive accumulation of extracellular matrix (ECM) and the activation of hepatic stellate cells (HSCs), which are influenced by epitranscriptomic and epigenetic factors. Recent advancements in epigenetic and epitranscriptomic research have revealed new opportunities for therapeutic interventions, particularly through the regulation of ferroptosis, a type of programmed cell death that is specifically linked to iron-dependent lipid peroxidation. In the context of liver fibrosis, a progressive scarring process that can progress to cirrhosis and ultimately end-stage liver disease, targeting these regulatory mechanisms to modulate ferroptosis presents a promising therapeutic strategy. This review aims to consolidate current knowledge on the epigenetic and epitranscriptomic control of ferroptosis and investigate its potential implications for the treatment of liver fibrosis.

MicroRNA‑96 promotes the proliferation and migration of breast cancer cells by inhibiting Smad7 expression

The present study aimed to investigate the effects of microRNA (miR)-96 on the proliferation and migration of breast cancer cells, and indicated that miR-96 may have a promoting role in breast cancer by inhibiting Smad7. Reverse transcription-quantitative (RT-q)PCR was used to detect the expression levels of miR-96 and Smad7 in breast cancer tissues and adjacent tissues. Western blotting and immunohistochemistry were conducted to determine the expression levels of SMAD7 in breast cancer and adjacent tissues. A dual luciferase assay was performed to verify the targeted binding between miR-96 and Smad7. Furthermore, the different expression patterns of miR-96 and Smad7 were compared in various breast cancer cell lines using RT-qPCR and western blotting. Among these cell lines, MDA-MB-231, which exhibited the highest expression of miR-96, was chosen for subsequent functional verification. The expression levels of miR-96 were significantly higher in breast cancer tissues compared with those in adjacent tissues. By contrast, the expression levels of Smad7 were significantly lower in breast cancer tissues compared with those in adjacent tissues. The dual luciferase assay revealed a targeted binding effect between miR-96 and Smad7. Notably, transfection with miR-96-5p mimics and short hairpin RNA-Smad7 markedly promoted the proliferation, adhesion, invasion and migration of breast cancer cells. Conversely, transfection with a miR-96-5p inhibitor and Smad7 overexpression plasmid exhibited the opposite trend. In conclusion, the expression levels of miR-96 were significantly elevated in breast cancer tissues compared with those in adjacent tissues. Overexpression of miR-96 was shown to promote the migration of breast cancer cells by downregulating the expression of Smad7. These findings indicated that miR-96 may serve as a prognostic marker for breast cancer.

The Role of the DNA Methyltransferase Family and the Therapeutic Potential of DNMT Inhibitors in Tumor Treatment

Members of the DNA methyltransferase (DNMT) family have been recognized as major epigenetic regulators of altered gene expression during tumor development. They establish and maintain DNA methylation of the CpG island of promoter and non-CpG region of the genome. The abnormal methylation status of tumor suppressor genes (TSGs) has been associated with tumorigenesis, leading to genomic instability, improper gene silence, and immune evasion. DNMT1 helps preserve methylation patterns during DNA replication, whereas the DNMT3 family is responsible for de novo methylation, creating new methylation patterns. Altered DNA methylation significantly supports tumor growth by changing gene expression patterns. FDA-approved DNMT inhibitors reverse hypermethylation-induced gene repression and improve therapeutic outcomes for cancer. Recent studies indicate that combining DNMT inhibitors with chemotherapies and immunotherapies can have synergistic effects, especially in aggressive metastatic tumors. Improving the treatment schedules, increasing isoform specificity, reducing toxicity, and utilizing genome-wide analyses of CRISPR-based editing to create personalized epigenetic therapies tailored to individual patient needs are promising strategies for enhancing therapeutic outcomes. This review discusses the interaction between DNMT regulators and DNMT1, its binding partners, the connection between DNA methylation and tumors, how these processes contribute to tumor development, and DNMT inhibitors' advancements and pharmacological properties.

Diagnosis of lung cancer using salivary miRNAs expression and clinical characteristics

OBJECTIVE

Lung cancer (LC), the primary cause for cancer-related death globally is a diverse illness with various characteristics. Saliva is a readily available biofluid and a rich source of miRNA. It can be collected non-invasively as well as transported and stored easily. The process is also reproducible and cost-effective. The aim of this study was to evaluate the salivary expression of microRNAs let-7a-2, miR-221, and miR-20a in saliva and evaluate their efficacy, using multiple logistic regression (MLR) model, in diagnosis of lung cancer.

MATERIALS

Samples of saliva were obtained from 40 lung cancer patients (20 lung adenocarcinoma and 20 lung squamous cell carcinoma) and 20 healthy controls. The levels of let-7a-2, miR-221, and miR-20a expression in saliva were assessed by RT-qPCR. Receiver operating characteristic (ROC) curve was utilized to assess the potential significance of miRNAs in saliva for lung cancer diagnosis with the use of multiple logistic regression (MLR), principal component analysis, and machine learning methods.

RESULTS

Diagnostic odds ratio (DOR) of miR-20a in lung adenocarcinoma diagnosis versus healthy control was higher than miR-221, and DOR of miR-221 was higher than let-7a-2. miR-20a demonstrated a higher DOR for small cell lung carcinoma versus healthy control compared to let-7a-2, which in turn exhibited a higher DOR than miR-221. MLR of miR-221, let-7a-2, miR-20a, and smoking habit using main effects led to accuracy of 0.725 (sensitivity: 0.80, specificity: 0.65) and AUC = 0.795 for differentiation of small-cell lung carcinoma from lung adenocarcinoma. Our results showed that MLR based on salivary miRNAs could diagnose LUAD and SCLC from healthy control using main effects and two-way interactions with the accuracy of 0.90 (sensitivity = 0.95 and specificity = 0.85).

CONCLUSION

A salivary miRNA-based MLR model is a promising diagnostic tool for lung cancer, offering a non-invasive screening option for high-risk asymptomatic individuals.

MicroRNAs miR-148a-3p, miR-425-3p, and miR-20a-5p in Patients with IgA Nephropathy

BACKGROUND/OBJECTIVES

IgA nephropathy (IgAN) is one of the most common forms of glomerulonephritis leading to renal failure. MicroRNAs have been shown to play an important role in the pathogenesis and clinical course of IgA nephropathy; therefore, they offer the possibility of noninvasive diagnosis of this disease and have some value in predicting disease prognosis. This study aimed to evaluate the plasma levels of miR-148a-3p, miR-425-3p, and miR-20a-5p in patients with IgA nephropathy and their correlation with selected clinical parameters.

METHODS

This study included 44 patients with IgA nephropathy and 46 control subjects.

RESULTS

The results of our study indicated that in patients with IgA nephropathy, the increased plasma levels of miR-148a-3p and miR-425-3p correlated negatively with eGFR values. According to the Haas classification, plasma levels of miR-20a-5p were statistically significantly increased in patients with histopathological changes classified as Stages 3, 4, and 5 compared with patients with histopathological changes classified as Stages 1 and 2.

CONCLUSIONS

The results of our study suggest the possible involvement of miR-148a-3p, miR-425-3p, and miR-20a-5p in the pathogenesis of IgA nephropathy.

Endometriotic lesions and their recurrence: A Study on the mediators of immunoregulatory (TGF-β/miR-20a) and stemness (NANOG/miR-145)

Endometriosis is a common estrogen-dependent disease that involves various cellular processes. Additionally, miRNAs play a crucial role in the development of the disease as an important component of the microenvironment. In this study, tissue specimens of eutopic and ectopic lesions of 20 women, whose endometriosis was later approved by the pathology laboratory, were biopsied through laparoscopy. As a control group, endometrial tissue specimens were collected from 20 women who underwent curettage for reasons unrelated to endometriosis. The expression levels of miR-20A and miR-145 and their target genes, TGF-β and NANOG, were measured in these samples as markers of stemness and immunomodulatory properties, respectively. The study also aimed to compare the expression levels of target genes and miRNAs in ectopic lesions regarding endometriosis recurrence post-surgery. The study revealed that the expression of TGF-β and NANOG genes was significantly upregulated in endometriotic tissues compared to the control group. There was also a notable increase in miR-20A and miR-145 expression in the endometriotic tissues compared to the control group. While there was no significant correlation between the expression of miR-20a and TGF-β, we observed a negative correlation between the expression level of miR-145 and NANOG. Additionally, the ROC curve analysis emphasized miR-14 as a potential biomarker for endometriosis over miR-20a. However, our findings on disease recurrence underscore the importance of miR-20a in the early detection of endometriosis recurrence.

Circulating Serum Micro-RNA as Non-Invasive Diagnostic Biomarkers of Endometriosis

BACKGROUND/OBJECTIVES

Endometriosis (END) is a painful gynecological condition. Clinical examination, imaging, and laparoscopy can provide a definitive diagnosis of END. Nonetheless, non-invasive biomarkers could help enhance and streamline the diagnostic process. Micro-RNAs (miRNAs), a family of small non-coding RNAs, could serve as useful non-invasive biomarkers for END. The aim of this study was to perform serum miRNA profiling in a retrospective cohort of women to identify miRNAs that are differentially expressed in END compared to control patients.

METHODS

RNA was isolated from serum samples of 67 END patients and 60 control women. The expression profile of a 754-miRNA panel was studied with RT-qPCR performed on a QuantStudio 12K Flex with the TaqMan OpenArray miRNA panel. A Censored Regression Model was used for miRNA differential expression analysis. Several gene-enrichment algorithms were employed to identify pathways related to the target genes of differentially expressed miRNAs.

RESULTS

One hundred and thirty miRNAs were detected in at least 75% of samples from either the END or the control group. Sixteen miRNAs were significantly modulated between the END and control groups. Enrichment analysis identified targets significantly overrepresented in numerous pathways involved in biological processes related to END, including inflammation, angiogenesis, cellular invasion, cell-cycle/cell proliferation, and estrogen and progesterone hormonal signaling.

CONCLUSIONS

Our study indicates that differentially expressed miRNAs between END patients and controls can be identified through liquid biopsy. Our findings also suggest a potential role for serum miRNAs in the pathophysiology of END, warranting further investigations for their use as non-invasive biomarkers.

miRNA-Mediated Mechanisms in the Generation of Effective and Safe Oncolytic Viruses

MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression by inhibiting the translation of target transcripts. The expression profiles of miRNAs vary in different tissues and change with the development of diseases, including cancer. This feature has begun to be used for the modification of oncolytic viruses (OVs) in order to increase their selectivity and efficacy. OVs represent a relatively new class of anticancer drugs; they are designed to replicate in cancer tumors and destroy them. These can be natural viruses that can replicate within cancer tumor cells, or recombinant viruses created in laboratories. There are some concerns regarding OVs' toxicity, due to their ability to partially replicate in healthy tissues. In addition, lytic and immunological responses upon OV therapy are not always sufficient, so various OV editing methods are used. This review discusses the latest results of preclinical and clinical studies of OVs, modifications of which are associated with the miRNA-mediated mechanism of gene silencing.

Recent advances in living cell nucleic acid probes based on nanomaterials for early cancer diagnosis

The early diagnosis of cancer is vital for effective treatment and improved prognosis. Tumor biomarkers, which can be used for the early diagnosis, treatment, and prognostic evaluation of cancer, have emerged as a topic of intense research interest in recent years. Nucleic acid, as a type of tumor biomarker, contains vital genetic information, which is of great significance for the occurrence and development of cancer. Currently, living cell nucleic acid probes, which enable the in situ imaging and dynamic monitoring of nucleic acids, have become a rapidly developing field. This review focuses on living cell nucleic acid probes that can be used for the early diagnosis of tumors. We describe the fundamental design of the probe in terms of three units and focus on the roles of different nanomaterials in probe delivery.

Feature engineering from meta-data for prediction of differentially expressed genes: An investigation of Mus musculus exposed to space-conditions

Transcription profiling is a key process that can reveal those biological mechanisms driving the response to various exposure conditions or gene perturbations. In this work, we investigate the prediction of differentially expressed genes (DEGs) when exposed to conditions in space from a set of diverse engineered features. To do this, we collected DEGs and non-differentially expressed genes (NDEGs) of Mus musculus-based experiments on the GeneLab database. We engineered a diverse set of features from factors reported in the literature to affect gene expression. An extreme gradient boosting (XGBoost) model was trained to predict if a given gene would be differentially expressed at various levels of differential expression. The test results on a separate holdout dataset showed an area under the receiver operating characteristics curves (AUCs) of 0.90±0.07, averaged across the five selected percentages of the most and least differentially expressed genes. Subsequently, we investigated the impact of selection of features, both individually with a correlation-based feature-selection procedure and in groups with a combination procedure, on the prediction performance. The feature selection confirmed some known drivers of adaptation to radiation and highlighted some new transcription factors and micro RNAs (miRNAs). Finally, gene ontology (GO) analysis revealed biological processes that tend to have expression patterns most suitable for this approach. This work highlights the potential of detection of differentially expressed genes using a machine learning (ML) approach, and provides some evidence of gene expression changes being captured by a diverse feature set not related to the condition under study.

Cancer cell-derived exosomal miR-20a-5p inhibits CD8+ T-cell function and confers anti-programmed cell death 1 therapy resistance in triple-negative breast cancer

Circulating miRNAs (cirmiRNAs) can be packaged into the exosomes, participating in intercellular communication, which affects the malignant progression and therapy resistance of triple-negative breast cancer (TNBC). Currently, immune checkpoint inhibitors that regulate T-cell function, especially antibodies against programmed cell death 1 (PD-1) or its ligand PD-L1, are emerging as new promising therapy for TNBC patients. However, only very limited patients showed complete or partial response to anti-PD-1 treatment. Dysfunction of CD8+ T cells is one of the key reasons for the immune escape of TNBC. The regulation of exosome-derived cirmiRNAs on CD8+ T cells in TNBC deserves more investigation. Here, the cirmiR-20a-5p level was significantly upregulated in the plasma of TNBC patients and culture supernatant of TNBC cells. High abundance of cirmiR-20a-5p was correlated with a worse prognosis of TNBC. cirmiR-20a-5p was secreted in the form of exosomes by TNBC cells. Exosomal cirmiR-20a-5p was internalized into CD8+ T cells and resulted into the dysfunction of CD8+ T. A mechanism study uncovered that cirmiR-20a-5p targeted the nuclear protein ataxia-telangiectasia (NPAT) and decreased NPAT expression in CD8+ T cells. An in vivo xenograft mouse model showed that cirmiR-20a-5p conferred TNBC to anti-PD-1 treatment resistance. Collectively, these findings indicated that cirmiR-20a-5p released by TNBC cells via exosome promotes cancer cell growth and leads to the immunosuppression by inducing CD8+ T cell dysfunction. This study suggests that targeting cirmiR-20a-5p might be a novel strategy for overcoming the resistance of TNBC to anti-PD-1 immunotherapy.

Bioengineered chimeric tRNA/pre-miRNAs as prodrugs in cancer therapy

Today, biologic prodrugs have led to targeting specific tumor markers and have increased specificity and selectivity in cancer therapy. Various studies have shown the role of ncRNAs in cancer pathology and tumorigenesis and have suggested that ncRNAs, especially miRNAs, are valuable molecules in understanding cancer biology and therapeutic processes. Most miRNAs-based research and treatment are limited to chemically synthesized miRNAs. Synthetic alterations in these miRNA mimics may affect their folding, safety profile, and even biological activity. However, despite synthetic miRNA mimics produced by automated systems, various carriers could be used to achieve efficient production of bioengineered miRNAs through economical microbial fermentation. These bioengineered miRNAs as biological prodrugs could provide a new approach for safe therapeutic methods and drug production. In this regard, bioengineered chimeric miRNAs could be selectively processed to mature miRNAs in different types of cancer cells by targeting the desired gene and regulating cancer progression. In this article, we aim to review bioengineered miRNAs and their use in cancer therapy, as well as offering advances in this area, including the use of chimeric tRNA/pre-miRNAs.

Upregulation of miR-20a-5p as the Potential MicroRNA Marker in Red Blood Cell Storage Lesion

Background

Packed red blood cells (PRBCs) can be preserved for 42 days, and stored PRBCs have slow, dangerous changes over time during storage. miRNA is approximately 22 nucleotides long, a small single-stranded noncoding RNA molecule. miRNA guides by pairing bases with their downstream target mRNA to regulate negative expression. They are essential in many life processes, including cell differentiation, proliferation, and apoptosis. Therefore, miRNA alterations may represent possible biomarkers of PRBC storage lesions. This study is aimed at validating the miR-20a-5p in PRBC storage. Study Design and Methods. A total of 20 PRBC samples were divided into day 1 and day 20 storage groups. Total miRNA was extracted and quantified by probe-based RT-qPCR assays to explore the potential role of miRNAs in PRBC storage lesions.

Results

Upregulated miR-20a-5p in PRBC storage on day 20 compared to day 1. MiR-20a-5p promoted cell survival, which may affect the downstream regulation and decrease PRBC viability in prolonged storage.

Conclusion

On this basis, this detection may help to assess the quality of stored PRBCs.

Plasmatic MicroRNAs and Treatment Outcomes of Patients with Metastatic Castration-Resistant Prostate Cancer: A Hospital-Based Cohort Study and In Silico Analysis

Prostate cancer (PCa) is one of the most common malignancies among men worldwide. Inevitably, all advanced PCa patients develop metastatic castration-resistant prostate cancer (mCRPC), an aggressive phase of the disease. Treating mCRPC is challenging, and prognostic tools are needed for disease management. MicroRNA (miRNA) deregulation has been reported in PCa, constituting potential non-invasive prognostic biomarkers. As such, this study aimed to evaluate the prognostic potential of nine miRNAs in the liquid biopsies (plasma) of mCRPC patients treated with second-generation androgen receptor axis-targeted (ARAT) agents, abiraterone acetate (AbA) and enzalutamide (ENZ). Low expression levels of miR-16-5p and miR-145-5p in mCRPC patients treated with AbA were significantly associated with lower progression-free survival (PFS). The two miRNAs were the only predictors of the risk of disease progression in AbA-stratified analyses. Low miR-20a-5p levels in mCRPC patients with Gleason scores of <8 were associated with worse overall survival (OS). The transcript seems to predict the risk of death regardless of the ARAT agent. According to the in silico analyses, miR-16-5p, miR-145-5p, and miR-20a-5p seem to be implicated in several processes, namely, cell cycle, proliferation, migration, survival, metabolism, and angiogenesis, suggesting an epigenetic mechanism related to treatment outcome. These miRNAs may represent attractive prognostic tools to be used in mCRPC management, as well as a step further in the identification of new potential therapeutic targets, to use in combination with ARAT for an improved treatment outcome. Despite the promising results, real-world validation is necessary.

Exosome-mediated miR-200a delivery into TGF-β-treated AGS cells abolished epithelial-mesenchymal transition with normalization of ZEB1, vimentin and Snail1 expression

Exosomes are small extracellular vesicles that can be derived from human cells such as mesenchymal stem cells (MSCs). The size of exosomes is at nano-scale range and owing to their biocompatibility and other characteristics, they have been promising candidates for delivery of bioactive compounds and genetic materials in disease therapy, especially cancer therapy. Gastric cancer (GC) is a leading cause of death among patients and this malignant disease affects gastrointestinal tract that its invasiveness and abnormal migration mediate poor prognosis of patients. Metastasis is an increasing challenge in GC and microRNAs (miRNAs) are potential regulators of metastasis and related molecular pathways, especially epithelial-to-mesenchymal transition (EMT). In the present study, our aim was to explore role of exosomes in miRNA-200a delivery for suppressing EMT-mediated GC metastasis. Exosomes were isolated from MSCs via size exclusion chromatography. The synthetic miRNA-200a mimics were transfected into exosomes via electroporation. AGS cell line exposed to TGF-β for EMT induction and then, these cells cultured with miRNA-200a-loaded exosomes. The transwell assays performed to evaluate GC migration and expression levels of ZEB1, Snail1 and vimentin measured. Exosomes demonstrated loading efficiency of 5.92 ± 4.6%. The TGF-β treatment transformed AGS cells into fibroblast-like cells expressing two stemness markers, CD44 (45.28%) and CD133 (50.79%) and stimulated EMT. Exosomes induced a 14.89-fold increase in miRNA-200a expression in AGS cells. Mechanistically, miRNA-200a enhances E-cadherin levels (P < 0.01), while it decreases expression levels of β-catenin (P < 0.05), vimentin (P < 0.01), ZEB1 (P < 0.0001) and Snail1 (P < 0.01). Leading to EMT inhibition in GC cells. This pre-clinical experiment introduces a new strategy for miRNA-200a delivery that is of importance for preventing migration and invasion of GC cells.

LncRNA FALEC increases the proliferation, migration and drug resistance of cholangiocarcinoma through competitive regulation of miR-20a-5p/SHOC2 axis

BACKGROUND

LncRNA is an important regulatory factor in the human genome. We aim to explore the roles of LncFALEC and miR-20a-5p/SHOC2 axis on the proliferation, migration, and Fluorouracil (5-FU) resistance of cholangiocarcinoma (CCA).

METHODS

In this study, the expression of FALEC and miR-20a-5p in CCA tissues and cell lines (HuCCT1, QBC939, and Huh-28) was detected by RT-qPCR. The FALEC in 5-FU-resistant CCA cell lines (QBC939-R, Huh-28-R) was knocked down to evaluate its effects on cell proliferation, migration, invasion, and drug resistance.

RESULTS

Our analysis showed that compared with the adjacent non-tumor tissues, FALEC was significantly higher in the CCA tissues and even higher in the samples from 5-FU-resistant patients. Knockdown FALEC increased the sensitivity of 5-FU and decreased migration and invasion of CCA cells. Dual luciferase reporter confirmed that FALEC sponges miR-20a-5p and down-regulated its expression. Moreover, SHOC2 leucine-rich repeat scaffold protein (SHOC2) was the target gene of miR-20a-5p. We found overexpression of FALEC (FALEC-OE) increased resistance of CCA cells to 5-FU significantly, which might contribute to increased SHOC2 expression and activation of the ERK1/2 signaling pathway.

CONCLUSIONS

In summary, our study revealed that down-regulation of FALEC could inhibit the proliferation, migration, and invasion of CCA cells in vitro by regulating the miR-20a-5p/SHOC2 axis and participating in 5-FU resistance by mediating the ERK1/2 signaling pathway.

miRNAs role in cervical cancer pathogenesis and targeted therapy: Signaling pathways interplay

Cervical cancer (CC) is the primary cause of cancer deaths in underdeveloped countries. The persistence of infection with high-risk human papillomavirus (HPV) is a significant contributor to the development of CC. However, few women with morphologic HPV infection develop invasive illnesses, suggesting other mechanisms contribute to cervical carcinogenesis. MicroRNAs (miRNAs, miRs) are small chain nucleic acids that can regulate wide networks of cellular events. They can inhibit or degrade their target protein-encoding genes. They had the power to regulate CC's invasion, pathophysiology, angiogenesis, apoptosis, proliferation, and cell cycle phases. Further research is required, even though novel methods have been developed for employing miRNAs in the diagnosis, and treatment of CC. We'll go through some of the new findings about miRNAs and their function in CC below. The function of miRNAs in the development of CC and its treatment is one of these. Clinical uses of miRNAs in the analysis, prediction, and management of CC are also covered.

Modulation of AKT Pathway-Targeting miRNAs for Cancer Cell Treatment with Natural Products

Many miRNAs are known to target the AKT serine-threonine kinase (AKT) pathway, which is critical for the regulation of several cell functions in cancer cell development. Many natural products exhibiting anticancer effects have been reported, but their connections to the AKT pathway (AKT and its effectors) and miRNAs have rarely been investigated. This review aimed to demarcate the relationship between miRNAs and the AKT pathway during the regulation of cancer cell functions by natural products. Identifying the connections between miRNAs and the AKT pathway and between miRNAs and natural products made it possible to establish an miRNA/AKT/natural product axis to facilitate a better understanding of their anticancer mechanisms. Moreover, the miRNA database (miRDB) was used to retrieve more AKT pathway-related target candidates for miRNAs. By evaluating the reported facts, the cell functions of these database-generated candidates were connected to natural products. Therefore, this review provides a comprehensive overview of the natural product/miRNA/AKT pathway in the modulation of cancer cell development.

The dual role of microRNA (miR)-20b in cancers: Friend or foe?

MicroRNAs, as non-coding transcripts, modulate gene expression through RNA silencing under normal physiological conditions. Their aberrant expression has strongly associated with tumorigenesis and cancer development. MiR-20b is one of the crucial miRNAs that regulate essential biological processes such as cell proliferation, apoptosis, autophagy, and migration. Deregulated levels of miR-20b contribute to the early- and advanced stages of cancer. On the other hand, investigations emphasize the tumor suppressor ability of miR-20b. High-throughput strategies are developed to identify miR-20b potential targets, providing the proper insight into its molecular mechanism of action. Moreover, accumulated results suggest that miR-20b exerts its effects through diverse signaling pathways, including PI3K/AKT/mTOR and ERK axes. Restoration of the altered expression levels of miR-20b induces cell apoptosis and reduces invasion and migration. Further, miR-20b can be used as a biomarker in cancer. The current comprehensive review could lead to a better understanding of the miR-20b in either tumorigenesis or tumor regression that may open new avenues for cancer treatment. Video Abstract.

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.

Identification of miRNA-mRNA regulatory network associated with the glutamatergic system in post-traumatic epilepsy rats

Background

Glutamate is one of the most important excitatory neurotransmitters in the mammalian brain and is involved in a variety of neurological disorders. Increasing evidence also shows that microRNA (miRNA) and mRNA pairs are engaged in a variety of pathophysiological processes. However, the miRNA and mRNA pairs that affect the glutamatergic system in post-traumatic epilepsy (PTE) remain unknown.

Methods

PTE rats were induced by injecting 0.1 mol/L, 1 μL/min FeCl₂ solution. Behavioral scores and EEG monitoring were used to evaluate whether PTE was successfully induced. RNA-seq was used to obtain mRNA and miRNA expression profiles. Bioinformatics analysis was performed to screen differentially expressed mRNAs and miRNAs associated with the glutamatergic system and then predict miRNA-mRNA interaction pairs. Real-time quantitative reverse transcription PCR was used to further validate the expression of the differential miRNAs and mRNAs. The microRNA-mRNA was subject to the Pearson correlation analysis.

Results

Eight of the 91 differentially expressed mRNAs were associated with the glutamatergic system, of which six were upregulated and two were downregulated. Forty miRNAs were significantly differentially expressed, with 14 upregulated and 26 downregulated genes. The predicted miRNA-mRNA interaction network shows that five of the eight differentially expressed mRNAs associated with the glutamatergic system were targeted by multiple miRNAs, including Slc17a6, Mef2c, Fyn, Slc25a22, and Shank2, while the remaining three mRNAs were not targeted by any miRNAs. Of the 40 differentially expressed miRNAs, seven miRNAs were found to have multiple target mRNAs associated with the glutamatergic system. Real-time quantitative reverse transcription PCR validation and Pearson correlation analysis were performed on these seven targeted miRNAs-Slc17a6, Mef2c, Fyn, Slc25a22, and Shank2-and six additional miRNAs selected from the literature. Real-time quantitative reverse transcription PCR showed that the expression levels of the mRNAs and miRNAs agreed with the predictions in the study. Among them, the miR-98-5p-Slc17a6, miR-335-5p-Slc17a6, miR-30e-5p-Slc17a6, miR-1224-Slc25a22, and miR-211-5p-Slc25a22 pairs were verified to have negative correlations.

Conclusions

Our results indicate that miRNA-mRNA interaction pairs associated with the glutamatergic system are involved in the development of PTE and have potential as diagnostic biomarkers and therapeutic targets for PTE.

Micro-RNAs Predict Response to Systemic Treatments in Metastatic Renal Cell Carcinoma Patients: Results from a Systematic Review of the Literature

Locally advanced or metastatic renal cell carcinomas (mRCCs) account for up to 15% of all kidney cancer diagnoses. Systemic therapies (with or without surgery) represent gold standard treatments, mostly based on tyrosine kinase inhibitors in association with immunotherapy. We provide an overview of the current knowledge of miRNAs as predictors of treatment resistance. A systematic review of the literature was carried out in January 2022 following the PICO methodology. Overall, we included seven studies—four testing plasmatic miRNAs, two exosomal miRNAs, and one urinary miRNA. A total of 789 patients were included (354 for plasmatic miRNAs, 366 for urinary miRNAs, and 69 for exosomal miRNAs). Several miRNAs were tested within the included studies, but six plasmatic (miR9-5-p¸ miR-192, miR193-3p, miR-501-3p¸ miR-221, miR-376b-3p) one urinary (miR-30a-5p), and three exosomal (miR-35-5p, miR-301a-3p, miR-1293) were associated with resistance to systemic treatments or treatment failure in mRCC patients. Results showed a fair accuracy of these biomarkers in predicting treatment resistance and overall survival. However, to date, the biomarkers tested have not been validated and their clinical uses are not recommended. Nevertheless, the literature results are encouraging; future large clinical trials are warranted to validate the effectiveness of these tools in clinical decision-making.