Analysis of androgen-sensitivity in rat prostate × mouse kidney cell hybrids

Variant androgen-sensitive cell lines were produced by fusing freshly isolated epithelial cells from the rat ventral prostate with a line of murine renal tumor (RAG) cells. The properties of the cloned lines of the prostate × RAG hybrids can be summarized as follows: (1) the modal chromosome number of the hybrid cell lines ranged from 68 to 176; (2) the cells had doubling times of 7.6-49.5 h; and (3) epitheloid, ameboid and intermediate morphologies were observed among the various lines. The proliferative response of various hybrid lines to treatment with 10 nM 5α-dihydrotestosterone was used to classify the hybrids as either very sensitive (>40% reduction in cell doubling time), sensitive (>10% reduction in doubling time) to androgens, or insensitive (<10% reduction in doubling time) to androgens. There was no direct relationship between the androgen-sensitivity of the cells and their androgen receptor content, suggesting that these variant cell lines may be useful for the study of the genetic factors involved in cellular responses to androgens.