N-Acetylglucosaminyltransferase V Expression is Implicated in Malignant Phenotype of Human Tongue Squamous Cell Carcinoma.

Abstract

The expression of GnT-V has been shown to correlate with tumor invasion, metastasis and poor prognosis in several tumors. We examined the expression of glycosyltransferases, N- acetylglucosaminyltransferase V (GnT-V) in 40 cases of human tongue squamous cell carcinoma (SCC) and its relationship to clinicopathological characteristics. Twenty-six of the 40 cases of SCC showed positive expression of GnT-V in cytoplasm of tumor cells by imunohistochemistry, whereas none of the 4 premalignant lesions showed positive signals for GnT-V. High expression of GnT-V was positively correlated with big tumor size (T category), infiltrative invasion pattern (vs. expansive), high histological malignancy (differentiation), and cervical lymph node metastasis. Furthermore, in the early clinical stage of SCC, the subsequent metastatic rate was significantly higher in SCCs that were GnT-V positive than in SCCs that were GnT-V negaive. All SCC cases examined showed increased GnT-V mRNA levels in comparison to normal tongue tissues by real-time PCR. Contrastively, GnT-V expression was not enhanced in premalignant lesions. These findings suggest that GnT-V expression is closely correlated with tongue SCC progression and the malignant phenotype.