Expression of GSDML Associates with Tumor Progression in Uterine Cervix Cancer

Gasdermin-like (GSDML) belongs to the gasdermin-domain-containing protein family (GSDMDC family) that is involved in carcinogenesis and hearing impairment. However, the role of GSDML in carcinogenesis remains unclear. In this study, we identified four isoforms of GSDML gene. The primary and longest isoform GSDML1 is widely expressed in human cancer cell lines. GFP-GSDML1 fusion protein was localized predominantly in the nucleus of human breast cancer MCF7 and cervical cancer HeLa cells but exclusively in the cytoplasm of hepatocellular carcinoma HepG2 cells. Importantly, immunohistochemistry analysis showed that the GSDML protein in the nuclei is expressed at a higher level in uterine cervix cancer tissues than in the adjacent cancer tissues and corresponding nonneoplastic tissues. Such significance was not observed in hepatocellular carcinoma tissues. Ectopic expression of GSDML1 enhanced the growth of cultured cells, whereas inhibition of its endogenous expression decreased proliferation. Furthermore, GSDML1 had significant effects on promoting bromodeoxyuridine incorporation in cells. However, GSDML1 could neither promote malignant transformation nor gain the ability of colony formation or carcinogenicity on nude mice. Collectively, these results suggest that GSDML can promote cell proliferation, and it might be correlated with carcinogenesis and progression of uterine cervix cancer.