Effect of prostaglandins on skin tumorigenesis.

Concomitant administration of prostaglandins E2 (PGE2) and F2alpha (PGF2alpha) with a carcinogen, 3-methylcholanthrene (MCA) to mice for 2 months markedly enhanced the occurrence of squamous cell carcinomas. Only epidermal cell hyperplasia occurred in mice treated with MCA alone by that time. Radioactivity measurements and electron microscopic autoradiography revealed that prostaglandins stimulate DNA, RNA and protein synthesis in neoplastic cells. These findings indicate that PGE2 and PGF2alpha can act as cocarcinogens on skin tumorigenesis.