Nfkb1 Polymorphism (rs4648068) Is Associated with Cell Proliferation and Motility in Gastric Cancer

Background: We have demonstrated previously that NFKB1 single nucleotide polymorphism (SNP) rs4648068 GG homozygote was associated with an increased risk of gastric cancer in the Chinese Han population. In this study, we constructed the recombinant plasmid pGL3-GG and pGL3-AA and investigated the function of rs4648068 by cell biology experiments. Methods: Quantitative real-time PCR was used to detect NF-KB SNP rs4648068 genotype in patients with gastric cancer. The section of NF-KB1 promoter containing this site were obtained by PCR technique and subcloned into the vector pGL3-Basic. Dual-Luciferase reporter assay was used to detect transcription activity of the constructed promoter. NF-κB1 protein levels were analyzed by western blot after transfection of the recombinant plasmid. Furthermore, proliferation and invasion ability of the transduced cells were also measured and compared. Results: The transcription activity of rs4648068 (A>G) by dual-Luciferase reporter assay suggested that the luciferase activity in the mutation group (pGL3-GG) was greater than that in the control group (pGL3AA), especially at the stimulation of LPS. We found that the luciferase activity was also influenced by pGL3-GG levels. The effects of NFKB1 rs4648068 were enhanced by rs4648065 on the transduced cells. Correspondingly, western blot analysis showed increased levels of p50 protein expression in the mutation groups. Our data indicated that the mutation of SNP rs4648068 strengthened the transcriptional activity of NF-KB1 and its expression levels, respectively. In addition, the transduction of pGL3 recombinant plasmid pGL3-GG improved the proliferation and invasion ability of gastric cancer cells. Conclusion: The transcriptional activity of NF-KB1 was associated with SNP rs4648068, and this functional SNP site has the important effects on cell proliferation and motility.