Sexual dimorphism of STGC3 tumor suppressor function in nasopharyngeal carcinoma CNE2 cells

STGC3 is a potential tumor suppressor in nasopha- ryngeal carcinoma. We previously found that CNE2 cells that re- expressed STGC3 formed smaller tumors in female mice than in male mice. Here, we investigated the sexual dimorphism of STGC3 as a tumor-suppressor in female and male nude mice injected sub- cutaneously with pcDNA3.1(+)-STGC3/CNE2 cells. ER-α was posi- tively expressed in vitro in the CNE2 cells. The pcDNA3.1(+)-STGC3/ CNE2 cell growth rate decreased after treatment with β-estradiol in vi- tro. There were significant differences in tumor size or mass between pcDNA3.1(+)-STGC3/CNE2 and control cases (P < 0.05), but there were significant differences in tumor size between female and male nude mice in the STGC3 transfection groups, and the pcDNA3.1(+)-STGC3/ CNE2 tumor growth rate in the female nude mice was the lowest in all cases (P < 0.05). There were no significant differences between female