Abstract:Objective To investigate the curative effect of microwave ablation for non-small cell lung cancer (NSCLC) patients, and to analyze the serum concentration changes of vascular endothelial growth factor (VEGF), arginase-1 (Arg-1), inducible nitric oxide synthase (iNOS) before and after microwave ablation and their correlations. Methods A total of 30 cases of healthy people (control group) and 30 cases of advanced NSCLC (test group) were selected. The serum concentrations of VEGF, Arg-1 and iNOS in control group and test group (before microwave ablation, the first postoperative day, the third postoperative day and the first postoperative month) were measured by enzymelinked immunosorbent assay (ELISA). Results The effective rate of microwave ablation for advanced NSCLC was 33.3% （10/30）, and the disease control rate was 70.0% （21/30）. The concentrations of VEGF, Arg-1 and iNOS in test group before microwave ablation were (816.56±13.26)pg/ml, (5.17±0.20)ng/ml and (544.18±13.93)pg/ml, which were higher than those in control group (93.43±9.93)pg/ml, (1.08±0.05)ng/ml and (8.08±0.33)pg/ml, and the differences were statistically significant (t=239.093,P＜0.001;t=110.359,P＜0.001;t=210.792,P＜0.001). The concentrations of VEGF were (708.41±10.49)pg/ml, (592.63±7.25)pg/ml and (521.91±8.32) pg/ml on the first day, third day and 1 month after microwave ablation in patients with advanced NSCLC, which were significantly lower than those before treatment (allP＜0.05). The homologous concentrations of Arg-1 were (5.95±0.10)ng/ml, (7.02±0.13)ng/ml and (7.67±0.92)ng/ml, which were significantly higher than those before treatment (allP＜0.05). The homologous concentrations of iNOS were (453.01±9.48)pg/ml, (393.21±9.42)pg/ml and (352.60±8.31)pg/ml, which were significantly lower than those before treatment (allP＜0.05). The expression of iNOS was positively related with VEGF in NSCLC patients before treatment (r=0.379,P=0.039), and the expression of Arg1 was negatively related with VEGF (r=-0.556,P=0.001). However, the expression of iNOS was not associated with Arg1 (r=-0.238,P=0.205). Conclusion Microwave ablation is effective for local therapy of NSCLC, which can directly kill cancer cells, and affect the levels of VEGF, Arg-1 and iNOS. VEGF has certain correlation with iNOS and Arg-1, but there was no correlation between iNOS and Arg-1. Microwave ablation can change the tumor microenvironment in a certain extent, and stimulate the body to produce anti-tumor immunity.

Key words:Lung neoplasms,Radiation therapy,Vascular endothelial growth factors,Arginase-1,Inducible nitric oxide synthase