Current and future perspectives on the regulation and functions of miR-545 in cancer development

Insights into the genetic and epigenetic mechanisms governing X-chromosome-linked-miRNAs expression in cancer; a step-toward ncRNA precision

Sex chromosomes play a significant role in establishing sex-specific differences in gene expression, thereby contributing to phenotypic diversity and susceptibility to various diseases. MicroRNAs (miRNAs), which are small non-coding RNAs encoded by both the X and Y chromosomes, exhibit sex-specific regulatory characteristics. Computational analysis has identified several X-linked miRNAs differentially expressed in sex-specific cancers. This review aims to elucidate the genetic and epigenetic mechanisms that govern the sex-specific expression of X- and Y-linked miRNAs, with particular attention to their functional role in regulating diverse cellular processes in different cancer pathways. In addition, this review provides a comprehensive understanding of the targeted therapeutic interventions and critical insights into the potential clinical implications of targeting sex-specific miRNAs. In conclusion, this review opens new horizons for further research to effectively translate these findings into viable treatment options.

Expression Levels of miR -124a, miR-545-3p and BDNF in the Peripheral Blood Mononuclear Cells Are Associated with the Severity of Autism

Background

People with autism frequently exhibit poor social skills, communication difficulties, and repetitive and stereotyped behaviors. MicroRNAs (miRNAs) are potential and promised targets in developing of new treatment strategies for autism. This study aimed to assess the relative expression of miR-124a, miR-34a-3p, miR-545-3p, miR-153, and BDNF in the blood samples of autistic children.

Methods

The children autism rating scale (CARS) was used to determine the severity of autism and to confirm the diagnosis. Blood samples were obtained from 50 patients and 40 age-/sex-matched healthy controls. Expressions of miR-545-3p, miR-34a-3p, miR-124a, and BDNF were evaluated using qRT-PCR. Pearson's correlation coefficient and regression analysis were used to check correlations between relative expressions of the miRNAs and BDNF. Biomarker potencies were assessed by ROC curve analysis.

Results

qRT-PCR analysis showed that the relative expressions of miR-545-3p, miR-34a-3p, miR-124a, and BDNF were significantly higher in the patients' group than the healthy controls. However, the relative expression of miR-153 was significantly lower in the case group than the control group. The relative expression of miR-124a was positively correlated with those of miR-545-3p and BDNF among the patients group. Also, the relative expressions of miR-545-3p and BDNF were positively correlated with each other. The ROC curve data also indicated that miR-124a, miR-34a-3p, miR-545-3p, miR-153, and BDNF could be possible diagnostic biomarker for CARS diagnosis (AUC=0.8328, AUC=0.8354, AUC=0.6727, AUC=0.8518 and AUC=0.8214, respectively).

Conclusions

Deregulation of miR-124a, miR-454-3p and BDNF might be considered as potential biomarkers for severity of autism.

CRISPR/Cas9 screens unravel miR-3689a-3p regulating sorafenib resistance in hepatocellular carcinoma via suppressing CCS/SOD1-dependent mitochondrial oxidative stress

AIMS

Therapeutic outcome of sorafenib in hepatocellular carcinoma (HCC) is undermined by the development of drug resistance. This study aimed to identify the critical microRNA (miRNA) which is responsible for sorafenib resistance at the genomic level.

METHODS

CRISPR/Cas9 screen followed by gain- and loss-of-function assays both in vitro and in vivo were applied to identify the role of miR-3689a-3p in mediating sorafenib response in HCC. The upstream and downstream molecules of miR-3689a-3p and their mechanism of action were investigated.

RESULTS

CRISPR/Cas9 screening identified miR-3689a-3p was the most up-regulated miRNA in sorafenib sensitive HCC. Knockdown of miR-3689a-3p significantly increased sorafenib resistance, while its overexpression sensitized HCC response to sorafenib treatment. Proteomic analysis revealed that the effect of miR-3689a-3p was related to the copper-dependent mitochondrial superoxide dismutase type 1 (SOD1) activity. Mechanistically, miR-3689a-3p targeted the 3'UTR of the intracellular copper chaperone for superoxide dismutase (CCS) and suppressed its expression. As a result, miR-3689a-3p disrupted the intracellular copper trafficking and reduced SOD1-mediated scavenge of mitochondrial oxidative stress that eventually caused HCC cell death in response to sorafenib treatment. CCS overexpression blunted sorafenib response in HCC. Clinically, miR-3689a-3p was down-regulated in HCC and predicted favorable prognosis for HCC patients.

CONCLUSION

Our findings provide comprehensive evidence for miR-3689a-3p as a positive regulator and potential druggable target for improving sorafenib treatment in HCC.