Therefore, larger and better-designed studies are required to overcome the limitations in the present study (particularly the information about Helicobacter pylori infection) and further confirm our observations. Acknowledgements This study was supported in part by National Institutes of Health grants R01 ES 11740-07 and CA 131274-01 (to Q. W.) and CA 16672 (to M. D. Anderson Cancer Center). We thank Margaret Lung and Kathryn Patterson for their assistance in recruiting the HTS assay subjects; Li-E Wang, Zhensheng Liu, Yawei Qiao, Min Zhao, Jianzhong He, and Kejin Xu for their laboratory assistance;

and Diane Hackett and Maude Veechfor for scientific editing. Electronic supplementary material Additional file 1: TGFB1 and VEGF genotype distributions and overall survival. The data provided represent the statistical analysis of TGFB1 and VEGF genotype distributions and overall this website survival. (DOC 69 KB) Additional file 2: TGFB1 and VEGF genotype distributions and 1-and 2-year survivals. The data provided represent the statistical analysis of TGFB1 and VEGF genotype distributions and 1-and 2-year survivals. (DOC 66 KB) References 1. Rohde H, Gebbensleben

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