GHRH and breast cancer: GHRH was shown to cause MAPK activation in MDA-MB-231 breast cancer cells via phosphorylation of Ras and Raf, and the GHRH antagonists MZ-J-7-138 and JV-1-92 were shown to block this pathway and suppress lung carcinoma growth in a manner that correlated with Ras inhibition [40, 48].