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-Prl, were examined. Among t hese agents, the phorbol ester, TPA, almost completely suppressed cell proliferation at the concentration of 10(-8) M, and induced remarkabl e 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, a-naphthyl a cetate esterase activity and CD11b, was observed In the differentiated cells. The data presented here suggest that TPA induces differentiati on of a human prostate cancer cell line into cells with the characteri stics of microglia.