CHRM1 and Familial prostate cancer: In prostate cancer, CHRM3 was demonstrated to promote growth; carbachol, a cholinergic agonist, showed a proliferative effect due to its agonistic activity on CHRM3; in early-stage human prostate cancer tissues, CHRM1 expression was high and appeared to play a role in prostate cancer proliferation and growth; but, using selective CHRM1 antagonists, such as pirenzepine and dicyclomine, showed significant inhibition of prostate cancer cell proliferation [186], suggesting that antagonism of CHRM1 could be a viable therapeutic target for prostate cancer [195].