[Expression of α-smooth Muscle Actin in Advanced Colorectal Cancer Tissue and Its Significance in Chemotherapy Response Prediction and Prognosis].

Objective To investigate the expression of α-smooth muscle actin(α-SMA)in advanced colorectal cancer tissue and its association with chemotherapy response and prognosis.Methods The expression of α-SMA was detected by immunohistochemistry in tissues from 52 advanced colorectal cancer patients who received oxaliplatin plus 5-fluorouracil regimen as first-line chemotherapy. Its relationship with clinical characteristics,chemotherapy response,and survival were analyzed.Results Of these 52 patients,29(55.8%)were α-SMA overexpression,and the expression of α-SMA protein was not significantly associated with the age(χ 2=0.113,P=0.730),gender(χ 2=0.515,P=0.332),tumor location(χ 2=3.675,P=0.159),and tissue differentiation(χ 2=1.852,P=0.604). The chemotherapy resistance rate was 65.5%(19/29)in patients with high α-SMA expression,which was significantly higher than that (13.0%,3/23)in patients with low α-SMA expression(χ 2=14.470,P=0.000). Patients with high α-SMA expression exhibited a significantly shorter progression-free survival(PFS)compared with those with low α-SMA expression [(6.4±1.0)months vs.(16.0±3.5)months; χlog-rank2=5.985,P=0.018]. Conclusion High α-SMA expression is associated with resistance to first-line chemotherapy and poor prognosis in advanced colorectal cancer patients.