EFFECT OF TUMOR-NECROSIS-FACTOR-ALPHA AND INTERFERON-GAMMA ON THE GROWTH OF HUMAN PROSTATE-CANCER CELL-LINES

Human recombinant tumor necrosis factor-alpha (rTNF-alpha, 10(-12)-10( -8) M) inhibited the proliferation of androgen-dependent LNCaP cells b y 32-56%. In contrast, proliferation of androgen-independent PC-3 and JCA-1 cells was only slightly inhibited, or not inhibited at all, resp ectively. Human recombinant interferon-gamma (rIFN-gamma, 500 U/ml) de creased proliferation of PC-3 and JCA-1 cells by 35% and 53%, respecti vely, but had no effect on LNCaP cells. Interestingly, the combination of rIFN-gamma and TNF-alpha had greater antiproliferative effects on JCA-1 cells than treatment with either cytokine alone. However, the an tiproliferative effects of this combination were similar to those obse rved for PC-3 or LNCaP cells treated with rIFN-gamma or TNF-alpha alon e, respectively. These data suggest that some forms of androgen-indepe ndent prostate cancer may benefit from a combination therapy of IFN-ga mma and TNF-alpha while the use of IFN-gamma alone may be more efficac ious in others.