The effect of prostaglandin modulators on prostate tumor growth and metastasis.

The purpose of this study was to investigate the effect of prostaglandin modulating drugs on the growth and metastasis of experimental prostate tumor. Nb rats bearing subcutaneous implants of an androgen-insensitive prostate adenocarcinoma were treated with indomethacin, a cyclooxygenase inhibitor, UK 38485, a thromboxane synthetase inhibitor, and nafazatrom, an antithrombotic agent which is thought to act by enhancing endogenous prostacyclin synthesis. Animals treated with these three drugs had significantly lower pulmonary metastasis than the untreated controls. The effect on primary tumor volume and mortality was variable. We conclude that shifting prostaglandin hemostasis in the tumor bearing animals in favor of prostacyclin, reduces pulmonary metastasis in this experimental tumor system.