High expression of COL6A1 correlates with poor prognosis in patients with breast cancer

Background: Breast cancer refers to one of the most common types of malignant cancer and accounts for the second leading malignant tumor in females. The overexpression of collagen type VI alpha 1 chain (COL6A1) has been associated with poor prognosis in patients with multiple solid malignant tumors. Aim: The present study aimed to investigate the clinical and prognostic significance of COL6A1 in breast cancer. Method: Tissue samples were obtained from 232 patients with breast cancer who underwent surgical resection between 2003 and 2007. Immunohistochemical COL6A1 expression pattern was performed. Statistical correlations between COL6A1 expression, clinicopathological characteristics, and prognosis were evaluated. Real-time polymerase chain reaction (PCR) and western blotting analyses were performed to confirm COL6A1 expression in patient-derived breast cancer and adjacent normal tissue. Result: Of 232 tissues from patients with breast cancer, 224 (96.6%) were positive for COL6A1. COL6A1 protein expression was significantly associated with postsurgical pathological T phase (P = 0.002) and N phase (P = 0.001). COL6A1 expression was negatively correlated with overall survival and recurrence-free survival. The mean COL6A1 mRNA (P = 0.021) and protein levels (P = 0.001) were significantly higher in breast cancer tissues compared with adjacent normal tissue. Conclusion: Our results suggest that overexpression of COL6A1 can be found in patients with higher T classification, N classification, or poor prognosis including death or recurrence. COL6A1 expression may be valuable for the prognostic evaluation of breast cancer.