Circ PSMC3 inhibits prostate cancer cell proliferation by downregulating DGCR8

OBJECTIVE The importance of circular RNAs in malignant tumors has attracted a lot of attention. Circular PSMC3 (CircPSMC3) is identified as a tumor suppressor in gastric cancer. The role of circPSMC3 in prostate cancer (PCa) remains unclear. Our study aims to uncover whether and how circPSMC3 functions in PCa development. PATIENTS AND METHODS Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was utilized to determine the level of circPSMC3 in PCa tissues and cell lines. The relation between circPSMC3 expression and patients' prognosis was analyzed as well. CircPSMC3 lentivirus was constructed and transfected into PCa cells. Cell migration and invasion abilities were detected through wound healing assay, transwell assay, and Matrigel assay, respectively. Western blot assay was performed to detect the protein level of DGCR8. RESULTS CircPSMC3 was lowly expressed in PCa tissues compared with adjacent normal tissues. Low expression of circPSMC3 was significantly downregulated in PCa cell lines as well. The migration and invasion abilities of PCa cells were significantly inhibited after circPSMC3 was overexpressed in vitro. Furthermore, DGCR8 expression increased remarkably via the overexpression of circPSMC3. CONCLUSIONS CircPSMC3 could suppress PCa cell migration and invasion by upregulating DGCR8.