ABSTRACT
@# Objective: To investigate the effect of VEGFR2 gene polymorphism V297I on the clinical outcomes in patients with advanced non-small cell lung cancer (NSCLC) treated with bevacizumab combining with chemotherapy. Methods:Atotal of 135 patients with advanced NSCLC, who were treated by bevacizumab plus platinum-based chemotherapy for first-line regimen, were included in this study. PCR-RFLP assay was used to detect the VEGFR2 genotypes in peripheral blood of patients and qPCR was used to detect the VEGFR2 mRNA in the cancer tissues of NSCLC patients. Logistic regression analysis was used to analyze the correlation between gene polymorphism and other variants, Kaplan-Meier assay to analyze the correlation between genotype and prognosis, and Cox regression model to analyze the risk factors for patients’PFS. Results: Of the polymorphisms analyzed, only polymorphism V297I was found to be of clinical significance. V297I locates in the coding region of VEGFR2, and it’s prevalence in the study population was as follows: CC genotype in 99 cases (73.33%), CT genotype in 33 cases (24.44%) and TT genotype in 3 cases (2.23%); the frequency of minor allele was 0.14, and the distribution of three genotypes was in accordance with Hardy-Weinberg equilibrium (P>0.05). The overall objective remission rate (ORR) of the 135 patients was 45.93%, the median progression free survival (mPFS) was 8.2 months and the median overall survival (mOS) was 20.8 months. The ORR, mPFS and mOS of patients with CT/TT genotype and CC genotype were 41.67%, 6.2 months, 18.9 months and 47.47%, 8.9 months and 21.5 months, respectively (all P<0.05).Additionally, the mRNAexpression of VEGFR2 in cancer tissues of the patients with CT/TT genotype was significantly higher than those with CC genotype (P< 0.01). The risk factors for patients’PFS included V297I, gender and ECOG score. Conclusion:Among advanced NSCLC patients treated by bevacizumab plus platinum-based chemotherapy, the polymorphism V297I of VEGFR2 may impact the clinical outcomes and prognosis of NSCLC patients treated with bevacizumab first line treatment by influencing the mRNAexpression of VEGFR2.