For example, there are a few FDA-approved cancer drugs available, such as cabergoline, lanreotide, degarelix, plerixafor, vismodegib and raloxifene, that target DRD1 (dopamine receptor D1), SSTR (somatostatin receptor), GnRH (gonadotropin-releasing hormone receptor), CXCR4 (C-X-C chemokine receptor type 4), SMO (smoothened homolog) and ES (estrogen receptor)2,3. Here, DRD1 is linked to cancer.