Abstract
BACKGROUND: Cyclin-dependent kinase 10 (CDK10) has recently been identified as a tumor suppressor and, concordantly, its encoding gene has frequently been found to be inactivated in various human cancers. Here, we examined the expression status of CDK10 in a panel of primary human breast cancers and evaluated its correlation with clinicopathological parameters and clinical outcome. METHODS: Western blotting was used to assess CDK10 protein levels in 20 paired breast cancer tissues and adjacent noncancerous tissues. In addition, immunohistochemistry was performed in 128 formalin-fixed, paraffin-embedded tumor tissues. Associations of CDK10 expression with various clinicopathological parameters were evaluated and Kaplan-Meier survival analyses and Cox proportional hazards models were used to estimate its effect on patient survival. RESULTS: We found that CDK10 protein expression was markedly decreased in cancer tissues compared to adjacent noncancerous tissues. Immunohistochemistry revealed decreased CDK10 levels in 65/128 (50.8 %) of the primary breast cancer tissues tested. These decreased levels were found to be significantly associated with lymph node metastasis (P = 0.003), advanced tumor stage (P < 0.001) and unfavorable overall survival (P < 0.001). Furthermore, multivariate analyses indicated that CDK10 expression may serve as an independent prognostic factor for survival (P = 0.001). CONCLUSION: Down-regulated CDK10 expression frequently occurs in breast cancers and correlates with disease progression and poor survival. CDK10 may serve as a prognostic biomarker for breast cancer.