Overexpression of ZFX and its involvement in squamous cell carcinoma of the tongue.

Zinc finger protein, X-linked (ZFX) has been identified as a transcriptional factor and is implicated in the development of variant types of cancer. Furthermore, it has been reported that ZFX is essential for the survival and self-renewal of embryonic stem cells. To investigate the involvement of ZFX in squamous cell carcinoma of the tongue, in the present study, we explored the expression of ZFX in clinical specimens from patients with squamous cell carcinoma of the tongue and the correlation between ZFX expression and multiple clinical pathological parameters. We further evaluated the impact of ZFX knockdown on the proliferation, colony formation ability, cell cycle distribution and survival of two human tongue squamous cell carcinoma cell lines to explore its critical role in the development of squamous cell carcinoma of the tongue. Our results showed that ZFX expression was aberrantly higher in samples from patients with squamous cell carcinoma of the tongue and revealed that ZFX expression is positively correlated with tumor grade and stage. Consistent with these findings, we further found that ZFX knockdown impaired cell proliferation and colony formation ability and induced cell apoptosis and cell cycle arrest in two human tongue squamous cell carcinoma cell lines. Our results indicate that ZFX is essential for the development and progression of squamous cell carcinoma of the tongue and represents a potential target for the development of effective therapy.