Prolactin receptor antagonists.

Efforts have been focused on the development of prolactin receptor (PRLR) antagonists, which, it is hoped, will be useful therapeutics for breast, prostate and possibly other cancers. Several approaches have been undertaken, including the production of pure antagonists and the combination of a PRLR antagonist with other antitumor molecules to increase efficacy. An alternative approach has been the development of a mimic of the natural PRL growth antagonist. This molecule is a combined antagonist/agonist since it inhibits signaling leading to growth, but promotes signaling leading to cell-cycle control, differentiation and apoptosis.