| Abstract: | We have compared the effects of indomethacin alone (100 microgram/mouse/day) with those of indomethacin plus adriamycin, 5-FU, nitrogen mustard, thioTEPA, and vincristine on B-16 tumor cell proliferation in vivo. As we have previously described, after four days of treatment with indomethacin, subcutaneous tumors were slightly smaller and lighter in weight, but contained more melanoma cells. Addition of indomethacin to cytotoxic regimens resulted in either no change or a decrease in the effectiveness of the chemotherapy. In previous studies we demonstrated that treatment of tumor-bearing mice with a long-acting synthetic analogue of PGE2 (di-M-PGE2) stimulated the synthesis of endogenous prostaglandins. In order to evaluate if these endogenously synthesized prostaglandins were responsible for the inhibition of B-16 growth in vivo, mice were treated with di-M-PGE2 or di-M-PGE2 plus indomethacin. Addition of indomethacin did not alter the tumor inhibitory effects of di-M-PGE2. |
