Elucidating the microRNA-203 specific biological processes in glioblastoma cells from comprehensive RNA-sequencing transcriptome profiling

Association of miR-203 Expression with Prognostic Value in Patients with Esophageal Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

This study aims to investigate the association between miR-203 expression and the prognostic value in patients with esophageal cancer by the method of systematic review and meta-analysis.

METHODS

We searched PubMed, Web of Science, Embase, and Cochrane Library to collect studies on the relationship between miR-203 expression and the prognostic value of esophageal cancer up to July 2023. Stata 15.0 statistical software was used for data analysis. Hazard ratio (HR) and 95% confidence interval (CI) were used as effect sizes.

RESULTS

A total of 6 studies were included in this review, including 476 patients with esophageal cancer. The results showed that miR-203 low expression was associated with worse overall survival (OS) in patients with esophageal cancer compared with miR-203 high expression (HR = 2.80, 95%CI: 1.99 ∼ 3.93, p < 0.001). The results of Egger's (p = 0.154) and Begg's Tests (p = 0.221) indicated no obvious publication bias. Sensitivity analysis verified the robustness of the results obtained in this study.

CONCLUSION

The expression of miR-203 is significantly correlated with the prognostic value in patients with esophageal cancer. Esophageal cancer patients with high expression of miR-203 had better prognosis than those with low expression of miR-203. Due to the limited studies included in this meta-analysis, more trials are needed to confirm the conclusions of this study in the future.

The role of RNA modification in the generation of acquired drug resistance in glioma

Glioma is the most common malignant tumor in the central nervous system. The clinical treatment strategy is mainly surgery combined with concurrent temozolomide chemotherapy, but patients can develop drug resistance during treatment, which severely limits its therapeutic efficacy. Epigenetic regulation at the RNA level is plastic and adaptable, and it can induce a variety of tumor responses to drugs. The regulators of RNA modification include methyltransferases, demethylases, and methylation binding proteins; these are also considered to play an important role in the development, prognosis, and therapeutic response of gliomas, which provides a basis for finding new targets of epigenetic drugs and resetting the sensitivity of tumor cells to temozolomide. This review discusses the relationship between the development of adaptive drug resistance and RNA modification in glioma and summarizes the progress of several major RNA modification strategies in this field, especially RNA m6A modification, m5C modification, and adenosine-to-inosine editing.

LncRNA BCYRN1 inhibits glioma tumorigenesis by competitively binding with miR-619-5p to regulate CUEDC2 expression and the PTEN/AKT/p21 pathway

Glioma is the most common malignant tumor in the central nervous system. Altered long noncoding RNAs (lncRNAs) are playing regulatory roles in physiological and pathogenic processes in cancer. Here, we uncovered a differentially expressed lncRNA called brain cytoplasmic RNA 1 (BCYRN1), and elucidated its function and molecular mechanism in the progression and development of glioma. Three fresh tumor tissues from glioma patients and three normal brain tissues from craniocerebral trauma patients were prepared for high-throughput RNA sequencing. Differential RNA transcripts and BCYRN1 were identified by RT-qPCR in glioma samples and controls. CCK-8, colony formation assays, flow cytometry, TUNEL assays, cell migration assays, wound-healing assays, and xenograft model were established to investigate the biological function of BCYRN1 both in vitro and in vivo. Various bioinformatics analysis, dual-luciferase reporter assays, biotinylated RNA pulldown assays, and rescue experiments were conducted to reveal the underlying mechanisms of competitive endogenous RNAs (ceRNAs). 183 lncRNAs were identified with significant dysregulation in glioma and randomly selected differential RNAs were further confirmed by RT-qPCR. Among them, BCYRN1 was the most downregulated lncRNA, and its low expression positively correlated with glioma progression. Functionally, BCYRN1 overexpression inhibited cell proliferation, migration in glioma cell lines, whereas BCYRN1 depletion resulted in the opposite way. MiR-619-5p was further confirmed as the direct target of BCYRN1. Mechanistically, miR-619-5p specifically targeted the CUE domain containing protein 2 (CUEDC2), and BCYRN1/miR-619-5p suppressed glioma tumorigenesis by inactivating PTEN/AKT/p21 pathway in a CUEDC2-dependent manner. Overall, our data presented that the reduced expression of BCYRN1 was associated with poor patient outcome in glioma. BCYRN1 functioned as a ceRNA to inhibit glioma progression by sponging miR-619-5p to regulate CUEDC2 expression and PTEN/AKT/p21 pathway. Our results indicated that BCYRN1 exerted tumor suppressor potential and might be a candidate in the diagnosis and treatment of glioma.

MiR-203a-3p Inhibits Pancreatic Cancer Cell Proliferation, EMT, and Apoptosis by Regulating SLUG

OBJECTIVE

The aim of the present research is to study the roles of miR-203a-3p on cell proliferation, migration, invasion, and epithelial-mesenchymal transition in pancreatic cancer.

METHODS

Transcription profiles were acquired from Gene Expression Omnibus database, which was used to screen out the differentially expressed microRNAs and messenger RNAs in pancreatic cancer. Pancreatic cancer tissues were used to verify the bioinformatics results by quantitative real-time polymerase chain reaction. The relationship between miR-203a-3p and SLUG was examined by TargetScan software, dual-luciferase reporter assay, and RNA immunoprecipitation. The Cell Counting Kit-8, wound healing, and transwell assays were conducted to investigate the proliferation, migration, and invasion capability of pancreatic cancer cells, respectively. The expression of epithelial-mesenchymal transition-related proteins was determined by the Western blot assay. Xenograft assay was performed to verify findings from in vitro assays.

RESULTS

Bioinformatic analysis found that a total of 113 microRNAs and 1749 messenger RNAs expressed differentially in pancreatic cancer tissues. Among these microRNAs, the expression of miR-203a-3p was significantly decreased in both pancreatic cancer tissues and cells. On the other hand, the SLUG expression was remarkably upregulated in pancreatic cancer tissues and cells in comparison with normal tissues and cells. Moreover, TargetScan software, dual-luciferase reporter assay, and RNA immunoprecipitation revealed that SLUG was a target of miR-203a-3p. The upregulation of miR-203a-3p expression inhibited the proliferation, migration, and invasion ability of pancreatic cancer cells by suppressing the epithelial-mesenchymal transition process via sponging SLUG.

CONCLUSION

These findings indicate that downregulation of miR-203a-3p in pancreatic cancer cells leads to high expression of SLUG, which promotes epithelial-mesenchymal transition process and induces cancer progression.