Efficacy of radiotherapy on intermediate and advanced lung cancer and its effect on dynamic changes of serum vascular endothelial growth factor and matrix metalloproteinase-9.

The present study intended to investigate efficacy of radiotherapy in the treatment of intermediate and advanced stage lung cancer and the effects on serum vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9). Serum levels of VEGF and MMP-9 of 77 patients with intermediate or advanced lung cancer were detected before and after the treatment. At the same time, 19 healthy people were selected as the control group. Gelatin zymography was applied to measure the activity of serum MMP-9, ELISA was performed to detect the VEGF and MMP-9 levels in the peripheral blood and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure the messenger RNA (mRNA) levels of VEGF and MMP-9 in serum. Results indicated that the overall response rate of radiotherapy on intermediate and advanced lung cancer reached 70.1%. Levels of serum VEGF and MMP-9 in the effective treatment group were significantly lower than those before the treatment (P<0.05). Furthermore, expression levels of VEGF and MMP-9 in the effective radiotherapy group were significantly lower than those in ineffective group (P<0.05), MMP-9 activity before treatment was significantly higher than that after treatment (P<0.05) and expression levels of VEGF and MMP-9 mRNA before treatment were significantly elevated compared with those after treatment (P<0.05). The results suggested that the expression levels of serum VEGF and MMP-9 may be useful indicators for the evaluation of the efficacy of radiotherapy in the treatment of intermediate and advanced lung cancer.