To investigate the expression of type Ⅰ collagen α1 chain protein (COL1A1) in triple negative breast cancer (TNBC), and its relationship with clinicopathological features and prognosis of TNBC.

A total of 148 TNBC specimens were collected from the Affiliated Cancer Hospital of Xinjiang Medical University from 2013 to 2015. The mRNA expression of COL1A1 was detected by fluorescence quantitative RT-PCR and the protein expression of COL1A1 was detected by Western blot. The expression of COL1A1 and α-smooth muscle actin (α-SMA) in TNBC were detected by immunohistochemistry. The relationship between the expression of COL1A1 and clinicopathological parameters and prognosis of TNBC patients was analyzed.

The mRNA and protein expression of COL1A1 in MDA-MB-231 cells were 1.696±0.486 and 0.550±0.088, respectively, which were higher than those in MCF-10A cells (1.020±0.231 and 0.350±0.083, P=0.032, P=0.046). The mRNA and protein expression of COL1A1 in TNBC tissues were 1.632 ±0.598 and 0.733 ±0.068, respectively, which were higher than those in paracancerous tissues (1.041±0.316 and 0.612±0.016, P=0.003, P=0.039). The high expression rates of COL1A1 and α-SMA in TNBC tissues were 35.8% and 56.7% respectively, which were higher than those in paracancerous tissues (16.7% and 30.0%, P=0.041, P=0.037). The expression of COL1A1 was correlated with tumor size, TNM stage, lymph node metastasis, vascular invasion and α-SMA expression (all P<0.05). The median survival time in COL1A1 high expression group was 64 months, which was lower than that in low expression group (73 months, P<0.05). Multivariate analysis of Cox proportional hazard regression model showed that COL1A1 expression was an independent influencing factor for the survival of TNBC patients (HR=3.952, P=0.004).

The high expression of COL1A1 in TNBC is an independent prognostic factor of TNBC patients.

Breast neoplasms, triple negative; Type Ⅰ collagen α1 chain; Extracellular matrix fibrosis; Prognosis