ZFX is a Strong Predictor of Poor Prognosis in Renal Cell Carcinoma

BACKGROUND: This study was designed to assay the expression of zinc finger protein X-linked (ZFX) in renal cell carcinoma (RCC) tissues and evaluate the correlation between ZFX expression and prognosis of RCC patients. MATERIAL/METHODS: The expressions of ZFX mRNA in 53 RCC tissues and 51 normal tissues were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemistry (IHC) technology was used to measure the expression of ZFX protein. Then chi-square test was conducted to verify the association between ZFX expression and clinical parameters. Next, we explored the overall survival rate of RCC patients with Kaplan-Meier analysis. Finally, the correlation between ZFX expression and the prognosis of RCC patients was evaluated by Cox regression analysis. RESULTS: The qRT-PCR result showed that the ZFX was significantly up-regulated in RCC tissues. As for the IHC consequence, the positive rate of ZFX expression in RCC specimens was 79.2%, while that in the normal control tissues was only 17.6%. Chi-square test showed that ZFX expression shared no close relationship with age, sex, or smoking (P>0.05), but was tightly associated with TNM stage, tumor size, and lymph node metastasis (P<0.05). Kaplan-Meier analysis showed that patients with ZFX positive expression had higher mortality than those with negative expression (P<0.05). Cox regression analysis revealed that ZFX expression had tight correlation with prognosis of RCC patients (HR=4.997, P=0.045, 95%CI=1.033–24.180). CONCLUSIONS: Our findings show that ZFX could be considered as a predictor for prognosis of RCC patients.