Effects of a tumor‐promoting agent on chondrogenesis

Abstract

Chondroblasts exposed to the phorbol ester, PMA, rapidly lose their polygonal morphology, and rapidly cease to synthesize or accumulate the chondroblast‐specific Type IV sulfated proteoglycan. This striking effect is reversible if the cells are kept in PMA for up to 72 hours. A longer exposure induces irreversible effects and results in a population of cells, the vast majority of which lack the phenotypic properties of terminal chondroblasts.