Overexpression of CDK2 is a prognostic indicator of oral cancer progression

Cyclins and cyclin-dependent kinases (CDKs) play key roles in cell cycle re gulation, a process of which dysregulation can lead to uncontrolled cell gr ow th and hence to cancer. We have already reported the alteration of CDK4 and cyclin D1 expression in oral cancer. In this study, we examined by immu nohistochemistry the expression of CDK2, and cyclins A and E in 20 normal o ral mucosa, 42 dysplastic epithelia, and 103 oral squamous cell carcinomas (SCCs). The expressions of CDK2, and cyclins A and E were not detected in t he normal epithelium and significantly altered from epithelial dysplasia to SCC, While there were no significant correlations between the expression o f cyclins A, E and the patients' survival, CDK2 expression was significantl y correlated with lymph node involvement (P=0.025), tumor differentiation ( P=0.032), mode of tumor invasion (P=0.017), and shorter survival period (P= 0.0173), These results suggest that the elevated expression of CDK2 is a cr itical factor in oral cancer progression and can be used as a negative pred ictive marker of the patients' prognosis.