miR-21 targets and inhibits tumor suppressor gene PTEN to promote prostate cancer cell proliferation and invasion: An experimental study

Objective: To study whether miR-21 targets and inhibits tumor suppressor gene PTEN can promote prostate cancer cell proliferation and invasion.

Methods: Prostate cancer cell lines PC-3 were cultured and divided into negative control group (NC group), miR-21 group, pcDNA3.1 group, miR-21+pcDNA3.1 group and miR-21+PTEN group that were transfected with different miR and plasmid, respectively. After 12 h and 24 h of transfection, the cell viability and invasive cell number were determined; after 24 h of transfection, Bcl-2, Survivin, MMP2, MMP9, PTEN, PI3K, and AKT expression in cells were determined.

Results: After 12 h and 24 h of transfection, OD value and invasive cell number of miR-21 group were significantly higher than those of NC group; after 24 h of transfection, Bcl-2, Survivin, MMP2, MMP9, PI3K and AKT expression levels were significantly higher than those of NC group while PTEN expression level was significantly lower than that of NC group; after 12 h and 24 h of transfection, OD value and invasive cell number of miR-21+pcDNA3.1 group were significantly higher than those of pcDNA3.1 group, and the OD value and invasive cell number of miR-21+PTEN group were significantly lower than those of miR-21+pcDNA3.1 group; after 24 h of transfection, Bcl-2, Survivin, MMP2 and MMP9 content of miR-21+pcDNA3.1 group were significantly higher than those of pcDNA3.1 group, and Bcl-2, Survivin, MMP2 and MMP9 content of miR-21+PTEN group were significantly lower than those of miR-21+pcDNA3.1 group.

Conclusions: miR-21 can target and inhibit tumor suppressor gene PTEN expression to promote prostate cancer cell proliferation and invasion.