Upregulated Expression Of SOX4 Is Associated With Tumor Growth And Metastasis In Nasopharyngeal Carcinoma

Background SOX4,which belongs to the sex-determining region Y-related high-mobility group(SRY)box family,plays critical roles in embryonic development,cell fate decision,differentiation and tumor development.Nasopharyngeal carcinoma(NPC)is one of the most common cancers in China and Southeast Asia.However,the molecular mechanisms of this disease remain unknown.Methods Immunohistochemistry was used to investigate the correlation between the expression of SOX4 with clinicopathologic variables as well as patients prognosis of NPC.Then we used NPC non-keratinizing cell line CNE2 for further in vitro studies.The effects of SOX4 on proliferation and migration of CNE2 cells were measured through knocking it down with siRNA by the starvation-refeeding experiment,CCK8 assay,wounding healing assay and transwell migration assay.After knocking down the expression of SOX4,the changes of the epithelial-mesenchymal transition(EMT)markers in CNE2 cells were measured by Western blot.At last,we took CCK8 assay to investigate its effects on chemotherapy drug cisplatin sensitivity.Results Overexpression of SOX4 was correlated with clinical stages,lymph node metastasis and Ki-67 expression in NPC(p<0.05).Besides,patients who expressed higher levels of SOX4 had poorer survival rate(p<0.05).While in vitro,after CNE2 cells releasing from serum starvation,the expression of SOX4 was upregulated.Moreover,knocking down SOX4 with siRNA decreased cell proliferation,migration and partially reversed the EMT phenotype of CNE2 cells.Conclusion Our data suggested that SOX4 might play an important role in regulating NPC progression and would provide a potential therapeutic strategy for NPC.