[Soft agar culture of human prostatic carcinoma--effect of testosterone on the clonal growth of the cells].

Soft agar cultures of human prostatic carcinoma cells obtained from prostates with needle biopsy and metastatic lymph nodes were examined. Colony formation were observed in 2 of the 4 needle biopsy specimens and in 7 of the 10 lymphatic nodes specimens. The plating efficiency was 0.04 to 0.43%. The effect of testosterone on the clonal growth of these cells in soft agar culture was studied. In half of the cases, colony formation was increased by the addition of testosterone. Whereas in the other cases, colony formation was not influenced by the testosterone. Clinically, most of the former cases responded well to the anti-androgen therapy. Neither EGF nor hydrocortisone showed any effect on the colony formation of the prostatic cancer cells in soft agar. These results suggest that primary culture of human prostatic cancer is possible in soft agar medium, and that androgen dependency of these cells can be examined in vitro.