Abstract:Objective To detect the expression and clinic significance of long non-coding RNA ZEB1-AS1 in breast cancer. Methods A total of 130 patients with breast cancer in Baoji Central Hospital of Shaanxi Province from June 2007 to April 2015 were selected. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of ZEB1-AS1 in breast cancer tissues and corresponding normal tissues, and the relationships between the expression level of ZEB1-AS1 and the clinic characteristics of the patients and their overall survival time were analyzed. siRNA was used to disturb the expression of ZEB1-AS1. CCK-8 assay, clone formation assay and Transwell assay were used to detect the proliferation, cloning ability and migration of breast cancer MCF-7 cells in control group, siRNA-1 group and siRNA-2 group. Results The expression level of ZEB1-AS1 in breast cancer tissues was higher than that in corresponding normal tissues ［M(QR): 0.001 6 (0.005 1) vs. 0.000 9 (0.001 5); Z=-4.426, P<0.001］. The higher expression of ZEB1-AS1 was correlated with lymphatic metastasis (χ2=9.148, P=0.027), negative human epidermal growth factor receptor 2 (χ2=5.039, P=0.025), triple negative breast cancer (χ2=4.597, P=0.032). The patients with the higher expression of ZEB1-AS1 had a shorter overall survival time compared with the patients with the lower expression of ZEB1-AS1 (χ2=14.340, P＜0.001). CCK-8 assay showed that knock down of ZEB1-AS1 after 72 h, the absorbance values of the control group, siRNA-1 group and siRNA-2 group were 0.605±0.049, 0.488±0.054, 0.417±0.038 respectively, with a statistically significant different (F=15.936, P<0.001), and the two siRNA groups were significantly inhibited in cell proliferation compared with the control group (both P<0.05). The colonies of the control group, siRNA-1 group and siRNA-2 group were 297.5±11.4, 192.0±12.1, 204.8±12.8 respectively, with a statistically significant different (F=112.526, P<0.001), and the two siRNA groups were significantly inhibited in the cell clone compared with the control group (both P<0.001). The migratory cells numbers of the control group, siRNA-1 group and siRNA-2 group were 184.5±8.6, 147.5±18.6, 57.6±7.3 respectively, with a statistically significant different (F=12.409, P=0.001), and the two siRNA groups were significantly inhibited in the cell migration (both P<0.001). Conclusion ZEB1-AS1 is overexpressed in breast cancer, overexpression of ZEB1-AS1 induces a shorter overall survival in breast cancer patients, and knock down of ZEB1-AS1 can inhibit the proliferation, migration and colony formation ability of the breast cancer cell line.

Key words:Breast neoplasms,Prognosis,ZEB1-AS1