Agarwal et al has reported a negative result of PRLR mAb LFA102 (a kind of humanized mAb binding with PRLR to inhibit the PRLR-mediated signaling transduction) for the treatment of metastatic PRLR positive breast cancer and metastatic castration resistant prostate cancer in phase I clinical trials (10). Here, PRLR is linked to breast carcinoma.