[The mechanism of HOTAIR regulating the proliferation and apoptosis of prostate cancer cells by targeting down-regulation of miR-152 to improve the expression of FOXR2].

Objective: To clarify the effect of FOXR2 on the proliferation and apoptosis of prostate cancer cells and to reveal the mechanism. Methods: The expression of FOXR2 in clinical samples of prostate cancer were detected by Quantitative Real-time PCR (qRT-PCR) and Western blotting. The CCK8 proliferation kit and the Annexin V-FITC apoptosis kit, flow cytometry were used to detect the proliferation and apoptosis of prostate cancer cells with or without the FOXR2 knockdown. Combined with the results of microRNA chip, we predicted the related miR-152 and detected the relationship between miR-152 and FOXR2 by luciferase reporter gene assay. The correlation between HOTAIR and miR-152 is clearly defined by software prediction and qRT-PCR. Results: FOXR2 had a relatively high expression in the prostate cancer tissue.The mRNA expression of FOXR2 is 4.9 times that of adjacent tissues, and the protein level was also significantly up-regulated. In the PC3 cell line, the specific knock-down of FOXR2 inhibits the proliferation of cells and promotes cell apoptosis. According to the microRNA chip results and luciferase reporter gene assay, we found miR-152 could regulate the expression of FOXR2; and FOXR2 3 'UTR had two miR-152 binding sites, all of which could control the expression of FOXR2. The results of LNCediting and qRT-PCR suggest that HOTAIR is negatively correlated with the expression of miR-152, and is involved in the regulation of miR-152 expression in prostate cancer. Conclusion: FOXR2 up-regulation can promote the proliferation and inhibit the apoptosis of prostate cancer cells because that HOTAIR restrains the expression of miR-152.