Combination of a novel growth hormone releasing hormone Antagonist JMR 132 and Tamoxifen enhances the inhibitory effects on growth of ZR 75 and T47D estrogen dependent human breas…

Background: Tamoxifen is the oldest selective estrogen receptor modulator (SERM) developed to antagonize the estrogen receptor function on human breast cancer cells. JMR 132 is a novel GHRH Antagonist proven to be potent inhibitor of tumor growth in estrogen receptor negative human breast cancer cell lines. A combination of both substances could induce a more potent growth inhibition, as compared to the single drugs. Methods: To determine inhibitory effects of the GHRH antagonist JMR 132 and Tamoxifen alone and in combination, estrogen receptor positive cell lines ZR 75 and T 47D were incubated with substances a…