Effect Of Insulin On Prostate Cancer Cells And Its Mechanism

ObjectiveTo study the effect of insulin on human prostate cancer cell lines (LNCaP, LNCaP-AI, and PC-3) and its possible mechanism.Methods(1) LNCap cells were cultured in the serous circumstance of long-term absence of hormone and we gained LNCaP-AI cell line which can accommodate the circuumstance without hormone.(2) LNCaP, LNCaP-AI and PC-3cells were treated with insulin. We detected the expression of insulin receptor(INSR) by Real-Time PCR, immunocytochemistry and Western Blotting. The effect of insulin on the cell growth, viability, migration and invasion was measured by cell counting, MTT, wound healing and transwell. The activation of MAPK pathway was determined by Western Blotting.Results(1) LNCaP-AI cells gradually suited for the no hormone circumstance and began to reproduce after six months. According to LNCaP cells, LNCaP-AI cells had a morphological change and high AR expression. But the expression of INSR had no difference.(2) Insulin increased the expression of INSR in all of three cell lins. On cell growth, viability, migration and invasion, insulin inhibited LNCaP cells, promoted PC-3cells, but had no effect on LNCaP-AI cells. Insulin also inhibited the activation of MAPK pathway of LNCaP cells, promoted it of PC-3cells, but had no effect on LNCaP-AI cells.ConclusionThrough MAPK signal pathway regulated by INSR, insulin can inhibit prostate cancer LNCaP cells, promoted it of PC-3cells, but had no effect on LNCaP-AI cells.