Low expression of NEK2 is associated with hepatocellular carcinoma progression and poor prognosis

BACKGROUND: NIMA-related kinase 2 (NEK2), a serine/threonine kinase, is located in the centrosome and is a member of cell cycle regulation related protein kinase (CCRK) family. Aberrant expression of NEK2 is linked with carcinogenesis and progression of various tumors. OBJECTIVE: To investigate the expression level of NEK2 and its relationship with clinicopathological factors in hepatocellular carcinoma (HCC). METHODS: Immunohistochemistry was used to measure the expression of NEK2 in 310 patients' specimen tissues and 197 adjacent normal liver tissues of HCC cases, and the subsequent prognostic value for each sample was estimated. RESULTS: NEK2 expression levels in HCC were lower than in adjacent tissues (49.7% vs. 72.6%, P < 0.001). First, patients with relatively low NEK2 expression had increased cancer progression and poorer prognosis than those with high expression. Second, NEK2 expression was significantly reduced in patients with large tumors (P = 0.025), with stage III Edmondson-Steiner Grading (P = 0.015). Third, patients' tumor size positively correlated with high AFP concentration (P = 0.017). Fourth, using the Kaplan-Meier survival curve, we found a lower survival rate in patients with decreased expression of NEK2 than those with high NEK2 expression in HCC (P = 0.029, Log-rank test). CONCLUSIONS: Low NEK2 expression might be a useful predictor in HCC as a poor prognostic factor, and could serve as a potential therapeutic target for HCC.