Phorbol ester induces differentiation of a human prostatic cancer cell line TSU-Pr1 into cells with characteristics of microglia.

The effects of various reagents on the induction of differentiation of the human prostatic cancer cell line, TSU-Pr1, were examined. Among these agents, the phorbol ester, TPA, almost completely suppressed cell proliferation at the concentration of 10(-8) M, and induced remarkable morphologic changes yielding cells with the microglial feature of an ameboid and/or ramified shape. More than 90% of the cells underwent the induction of morphologic changes by day 7 after treatment with 10(-8) M TPA. The expression of reliable microglial markers, alpha-naphthyl acetate esterase activity and CD11b, was observed in the differentiated cells. The data presented here suggest that TPA induces differentiation of a human prostate cancer cell line into cells with the characteristics of microglia.