Prognosis prediction of colorectal cancer by high expression of branched chain amino acid aminotransferase 1

Abstract

Objective To study the relationship between the high expression of branched chain amino-acid transaminase 1 (BCAT1) and clinicopatholotical features as well as survival outcome for colorectal cancer. Methods A retrospective analysis of seventy two eligible patients diagnosed as coloretal cancer between January 2007 and May 2013 was performed. The incidence of positive BCAT1 staining in adjacent normal tissues (n=20) and colorecal cancer tissues (n=72) were analyzed by immunohistochemical method. The relationship between the high expression of BCAT1 in colorectal carcinoma and the clinicopathological characteristics and the prognosis was further conducted. Results The positive expression rate of BCAT1 protein in colorectal cancer tissues was 65.3% (47/72), significantly higher than that in adjacent normal colonic tissues (30.0%); the difference was statistically significant (χ2=7.976, P=0.005). The positive expression of BCAT1 protein was higher in tissues with rectum, T staging, lymph node metastasis, and TNM III+IV stage (χ2=5.296, 4.541, 11.387, 5.091, respectively, all P<0.05). Prognosis analysis showed that the overall survival of colorectal cancer patients with negative expression of BCAT1 was significantly better than those with positive expression of BCAT1, and 5-year survival rate was 52.8% and 15.1%, respectively (χ2=9.242, P=0.002). Conclusions Positive expression of BCAT1 protein prompts to poor pathological characteristics and prognosis for colorectal cancer patients. BCAT1 is a potential biological target for diagnosis and prognosis judgement of colorectal cancer. Key words: Colorectal neoplasms; Transaminases; Amino acids, branched-chain; Forecasting; Prognosis