lncRNA ZFAS1 Is Involved in the Proliferation, Invasion and Metastasis of Prostate Cancer Cells Through Competitively Binding to miR-135a-5p

Background: Prostate cancer (PCa) is a common malignant tumor in men. lncRNA ZFAS1 plays a carcinogenic role in many types of cancer; however, its potential role in PCa remains unclear. The current study aimed to determine the expression and function of ZFAS1 in PC. Methods: The ZFAS1 expression in PC tissues and cells was determined by quantitative polymerase chain reaction (qPCR). SiZFAS1, miR-135a-5p mimic and miR-135a-5p inhibitor were transfected into PCa cells. The direct target of ZFAS1 was predicted by Starbase and verified by dual-luciferase reporter. Cell viability, proliferation, apoptosis, migration and invasion of the PCa cells were determined by cell counting kit-8, clone formation assay, flow cytometer, scratch and Transwell assay, respectively. The expression levels of related proteins and mRNAs were determined by Western blotting and qPCR. Results: ZFAS1 expression was up-regulated in PCa cells and tissues. ZFAS1 could competitively bind to miR-135a-5p in PCa cells, and down-regulation of ZFAS1 inhibited cell viability, proliferation, migration, invasion of PCa cells and the occurrence of epithelial-mesenchymal transformation (EMT) and promoted apoptosis of PCa cells and increased the miR-135a-5p expression. Moreover, the function of miR-135a-5p mimic in PCa cells was consistent with ZFAS1 knockdown, while the function of miR-135a-5p inhibitor was opposite to that of miR-135a-5p mimic in PCa cells. The results showed that knocking down ZFAS1 could attenuate the effects of miR-135a-5p inhibitor on cell proliferation, invasion and EMT of PCa cells. Conclusion: Knocking down ZFAS1 could inhibit the proliferation, invasion and metastasis of PCa cells through regulating miR-135a-5p expression.