Serotonin was reported to have a stimulatory effect on PCa cell growth mediated through 5-HT1A and 5-HT1B receptors; however, another study did not support the hypothesis of a prominent role of 5-HT1A and 5-HT1B receptors in the control of PCa cell growth at physiological concentration of 5-HT [51,52,53]. The gene discussed is HTR1A; the disease is posterior cortical atrophy.