Cadmium-induced malignant transformation of human prostate epithelial cells.

Prostate cancer has become epidemic, and environmental factors such as cadmium may be partly responsible. This study reports malignant transformation of the nontumorigenic human prostatic epithelial cell line RWPE-1 by in vitro cadmium exposure. The cadmium-transformed cells exhibited a loss of contact inhibition in vitro and rapidly formed highly invasive and occasionally metastatic adenocarcinomas upon inoculation into mice. The transformed cells also showed increased secretion of MMP-2 and MMP-9, a phenomenon observed in human prostate tumors and linked to aggressive behavior. Cadmium-induced malignant transformation of human prostate epithelial cells strongly fortifies the evidence for a potential role of cadmium in prostate cancer.