Hypoxia promotes the growth and invasiveness of prostate cancer cells by down-regulating miR-132 in vitro / 中华男科学杂志

ABSTRACT

<p><b>Objective</b>To explore the expression of miR-132 in prostate cancer and its effects on the growth and invasiveness of prostate cancer cells and the influence of hypoxia on the level of miR-132 and biological behavior of prostate cancer cells.</p><p><b>METHODS</b>Real time PCR was used to measure the expression level of miR-132 in the prostate cancer tissue, analyze its relationship with the clinical stage and Gleason score of prostate cancer, and determine the influence of hypoxia on the miR-132 level in the human prostate cancer PC3 cell line in vitro. Sulfor-hodamine B chromatometry and Matrigel invasion assay were employed to detect the effects of hypoxia and miR-132 mimic plasmid transfection on the viability and invasiveness of PC3 cells in vitro.</p><p><b>RESULTS</b>The miR-132 level in the prostate cancer was significantly declined to 52.38% (in T1－T2 stages) and 21.59% (in T3－T4 stages) of that in the cancer-adjacent tissue (both P<0.01). In hypoxia, the expression of miR-132 was significantly decreased in the PC3 cells (P<0.01). After 48 and 72 hours of transfection with miR-132 mimic plasmid, the viability of the PC3 cells was markedly reduced (P<0.05 or P<0.01), and their invasiveness decreased by 57.5% after 48 hours (P<0.01). However, there was no significant difference in the viability or invasiveness of the PC3 cells transfected with miR-132 mimic plasmid between normoxia and hypoxia.</p><p><b>CONCLUSIONS</b>The reduced expression of miR-132 is closely related to the clinical stage and Gleason score of prostate cancer. Hypoxia increases the viability and invasiveness of prostate cancer cells in vitro by down-regulating the expression of miR-132 and consequently may promote the growth and metastasis of prostate cancer.</p>