Effect of hormones on growth and ATP content of a human prostatic carcinoma cell line, LNCaP‐r

The use of ATP content as a measurement for cell growth was evaluated in the LNCaP prostatic cancer cell line. ATP content was found to correlate well with cell counts and was an easy and reliable method for following the effect of substances on cell growth. During cultivation for 9 days no effect on cell counts or ATP content could be seen when testosterone (10^-10 to 10^-6 M), estradiol-17β (10^-10 to 10^-5 M), 5α-DHT (10^-9 to 10 ^-6 M), prolactin, vitamin A, or antiandrogen was added to the cell medium in different combinations. However, a weak positive effect was seen on the mitotic index when 10 or 100 nM 5α-DHT was added to the cells, whereas 1 μM 5α-DHT inhibited cell growth. Thus despite the fact that this LNCaP line contained 16 fmol androgen receptor/mg protein (K(d) 0.6 nM), it is unresponsive to hormones and should be designated LNCaP-r (resistant). Chromosome analysis revealed that a shift in the modal chromosome number had occurred from the original LNCaP line, which could account for the lack of hormonal sensitivity.