Integrated study of miR‐215 promoting breast cancer cell apoptosis by targeting RAD54B

BACKGROUND MicroRNAs (miRNAs) are widely distributed in cells and participate in the regulation of the pathophysiological process of many diseases. As an important part of non-coding RNA, miRNAs regulate a variety of molecules and signal pathways in tumour cells. However, the evidence for regulatory mechanisms of specific miRNAs in tumour cells is still lacking. METHODS In this study, we used transcriptomics analysis and integrated a variety of public databases to screen miRNAs that have key regulatory effects on breast cancer (BC). In addition, we used in vitro and in vivo studies and combined clinical samples to verify its regulatory mechanism. RESULTS We found that among the specific miRNAs, miR-215-5p is a key regulator in BC. Compared with normal adjacent tissues, miR-215-5p has a lower expression level in BC tissues. Patients with high expression levels of miR-215-5p have a longer survival time. miR-215-5p can specifically target the 3'UTR region of RAD54B mRNA and down-regulate the expression of RAD54B, thereby inhibiting the proliferation of BC cells and promoting the apoptosis of BC cells. CONCLUSIONS Finally, we found that miR-215-5p can be used as an important biomarker for BC. We have clarified its function and revealed its mechanism of targeting RAD54B mRNA for the first time. This may provide important clues to reveal the deeper molecular regulation mechanism of BC.