Prognostic significance of HOXD13 expression in human breast cancer

Homeobox protein Hox-D13 has been recognized as a tumor suppressor in pancreatic cancer. To evaluate the function of HOXD13 in invasive breast cancer pathogenesis, we examined HOXD13 expression in 434 breast cancer tissues and 230 their counterpart normal breast tissues by immunohistochemistry using a tissue microarray (TMA). The association between HOXD13 expression and clinicopathological factors was analyzed by use of Chi-square test. Kaplan-Meier survival curves and log-rank tests were applied to analyze the survival status. Cox regression was applied for multivariate analysis of prognosis. We found that low HOXD13 expression accounts for 84.3% in breast cancer tissues. Low HOXD13 expression was significantly associated with large tumor size (P=0.038) and positive lymph node metastasis (LNM) (P=0.026). In Kaplan-Meier survival curves and log-rank tests, the patients with HOXD13-negative breast cancer showed significantly poorer outcomes (69.867 ± 1.058 months) in terms of overall survival (OS) than positive-HOXD13-expression patients (76.248 ± 1.069 months) (P=0.003). And in multivariate analysis, low level of HOXD13 expression was a significant unfavorable prognostic factor. So we conclude that down-regulation of HOXD13 might be a potentially useful prognostic marker for patients with breast cancer.