THE EFFECTS OF BETA-HUMAN CHORIONIC-GONADOTROPIN ON THE IN-VITRO GROWTH OF BLADDER-CANCER CELL-LINES

The effects of human chorionic gonadotrophin (hCC) and its subunits on in vitro bladder cancer cell growth have been assessed using the a te trazolium salt reduction assay (MTT). Intact hCG, alpha-hCG and beta-c ore hCG all had no effect on cell growth, while beta-hCC increased MTT reduction in all four bladder cancer lines tested. The magnitude of b eta-hCG stimulation was maximal in the T24 line, which does not itself produce beta-hCG and appeared to be correspondingly lower in beta-hCG -secreting lines. The addition of antibodies to beta-hCG inhibited MTT reduction among high secretors but failed to inhibit MTT reduction in non-beta-hCG producers. These results are consistent with the poor pr ognosis associated with beta-hCG expression by bladder tumours in vivo and suggest an autocrine/paracrine stimulation of tumour growth by en dogenously produced beta-hCG.