Chronic stress-promoted growth of OC xenografts at the primary sites, where there is relatively high level of HTR1E (Figures 1E-1I), can be inhibited by the injection of extrinsic serotonin, more strongly by specific HTR1E agonist (Figures 7B-7C), supporting that HTR1E mediates a major tumor-suppressive role downstream of serotonin against other serotonin receptor subtypes to protect ovarian cells. This evidence concerns the gene HTR1E and neoplasm.