Epidermal growth factors enhances viral transformation of granulosa cells.

Kirsten sarcoma virus produced a low incidence of transient morphological transformation in primary cultures of rat ovarian granulosa cells. In the presence of epidermal growth factor, the incidence of transient transformation increased severalfold and two continuous cell lines were established. Epidermal growth factor, a naturally occurring polypeptide hormone, appears to act here as a tumor promoter in the retrovirus-induced transformation of a mesodermally derived epithelium.