Abstract
The present study aimed to investigate the expression status and clinical implications of DEK in breast cancer, in order to contribute to developments in breast cancer management. DEK expression status was detected in 628 breast cancer specimens by western blot analysis and immunohistochemistry staining, and the correlation between DEK protein and clinico‑pathological parameters and prognosis of breast cancer was subsequently determined. In comparison to para-carcinoma tissues, DEK protein was highly expressed in breast cancer specimens and was correlated with chemotherapy resistance. In total, 61.94% (389/628) of breast cancer cases exhibited high expression of DEK. According to universal analysis, it was observed that age, tumor size, histological grade, metastatic nodes and distant metastasis (P=0.024, 0.001, 0.001, 0.001 and 0.001 respectively) are key factors associated with DEK. Furthermore, compared with samples with no or low DEK protein expression, high DEK expression resulted in a significantly increased distant metastasis rate and poor disease‑specific survival (P=0.001). In addition, DEK protein was detected as an independent prognostic factor (P=0.001) in the Cox regression analysis. DEK was correlated with chemotherapy resistance and may be an independent prognostic factor for breast cancer, as well as a potential therapeutic target.