Ninein-like protein is overexpressed in head and neck squamous cell carcinoma and contributes to cancer growth and resistance to apoptosis

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and survival rates are not improving. Better understanding of the molecular mechanisms of this disease becomes critical to develop more effective treatments. Ninein-like protein (Nlp), a recently identified centrosome-associated protein, is a key regulator in centrosome maturation, which contributes to chromosome segregation and cytokinesis. Recent studies have revealed overexpression of Nlp in several types of human tumors and suggested it was a potential oncogenic protein. To investigate the role of Nlp in the development of HNSCC, expression of Nlp in tumor tissues of 76 HNSCC patients were analyzed, and the correlations of Nlp expression with the clinicopathological characteristics were evaluated. Our data showed overexpression of Nlp in tumor tissues compared with their normal counterparts. Moreover, overexpression of Nlp correlated with tumor differentiation and immunohistochemistry analysis of preinvasive dysplasia and squamous cell carcinoma showed that overexpression of Nlp occurred in premalignant lesions. Biological studies with human HNSCC cell lines indicated that overexpression of Nlp promoted cell proliferation and inhibited cisplatin-induced apoptosis. Taken together, these results suggest a novel mechanism that is closely related to malignant phenotype and anti-cancer drugs resistance of HNSCC and support the notion that Nlp overexpression might contribute to the development of HNSCC.