Genetic polymorphism of rs9564966 G > A on 13q22.1 predicts poor survival for Chinese patients with gastric cancer

Genomic variants in Fas-mediated apoptosis pathway predict a poor response to Platinum-based Chemotherapy for Chinese Gastric Cancer Patients

Platinum-based adjuvant chemotherapy is very common for gastric cancer (GC) patients, but the chemotherapy sensitivity is very heterogeneous. The genomic variants and the gene-gene interactions involved in Fas-mediated apoptosis pathway including Fas (FAS 1377 G > A and 670 A > G), FasL (FASL 844 C > T) and caspase-8 (CASP8 -652 6N ins > del or I > D), may paly vital roles in the response to platinum-based treatment. In our investigation, 662 stage II-III postoperative GC patients were enrolled between 1998 and 2006. 261 patients accepted platinum-based regimens and the remaining 401 were not. The log rank tests, Kaplan Meier plots, Pearson chi-square tests, Student t-tests and Cox regression analyses were performed. For the chemotherapy cohort, FAS 1377 G > A or FAS 670 A > G variants alone was related with inferior survival, and a greater than additive effect was identified when patients simultaneously carrying FAS 1377 GA and FAS 670 GA genotypes. But the poor response was neutralized when patients simultaneously carrying FASL 844 C > T or CASP8 -652 6N ins > del mutations. Our study suggested that FAS 1377 G > A and FAS 670 A > G variants may serve as potential biomarkers to predict the response to platinum-based adjuvant chemotherapy, and the gene-gene interactions involved in Fas-mediated apoptosis pathway may enhance or neutralize the chemosensitivity.

Association of Genetic Polymorphisms in FOXA1 with the Progression of Genetic Susceptibility to Gastric Cancer

Objective

To investigate the relationship between polymorphism of FOXA1 gene rs12894364 and rs7144658 and susceptibility to gastric cancer.

Methods

A case-control study was conducted to select 577 cases of primary gastric cancer and 678 cases of normal control. We extracted whole blood genomic DNA and amplified the target gene fragment by PCR. The genotyping and allele was tested through a snapshot method.

Results

There was no significant difference in the frequency distribution of genotype between the case group and control group (P > 0.05). Stratified analyses showed the SNPs were not correlated with the susceptibility of GC according to different age, gender, cigarette smoking, and alcohol drinking status.

Conclusion

There is no significant correlation between the polymorphisms of FOXA1 gene rs12894364 and rs7144658 and the risk of gastric cancer.

MAP3K1 rs889312 genotypes influence survival outcomes of Chinese gastric cancer patients who received adjuvant chemotherapy based on platinum and fluorouracil regimes

Background

For patients with gastric cancer (GC), adjuvant chemotherapy is a standard therapy. However, the responses to the treatment are quite different. Mitogen-activated protein kinase (MAPK) pathway is a core pathway that modulates the efficacy of anticancer drugs. The purpose of our study was to investigate the clinical significance of one pivotal functional gene polymorphism in the MAPK pathway – MAP3K1 rs889312 – in patients with stage II GC to stage III GC.

Methods

The genotypes of MAP3K1 rs889312 were analyzed in 591 GC patients enrolled in this study who had received radical gastrectomy. Among them, 204 patients accepted adjuvant chemotherapy based on platinum and fluorouracil (PF) regimens after an operation. Cox regression analysis, log-rank test and Kaplan–Meier method were used to explore the link between MAP3K1 rs889312 variant and overall survival (OS) of GC.

Results

Compared with the AA genotype (mean OS of 68.12 months), MAP3K1 rs889312 AC/CC significantly reduced the mean OS of 56.83 months in patients who received adjuvant chemotherapy only. In addition, AC/CC genotype had a negative impact on OS of patients who received oxaliplatin-based therapy (HR, 8.253; 95% CI: 1.119–60.853, log-rank p=0.013). Stratification analysis showed that MAP3K1 rs889312 AC/CC significantly reduced OS of patients with tumors smaller than or equal to 5 cm in size (HR, 3.706; 95% CI: 1.329–10.335, p=0.012), poorly differentiated tumors (HR, 3.002; 95% CI: 1.076–8.377, p=0.036) and intestinal tumors (HR, 4.780; 95% CI: 1.138–20.073, p=0.033).

Conclusion

Our findings suggested that MAP3K1 rs889312 single-nucleotide polymorphism may be considered as a biomarker for adjuvant chemotherapy reaction and can predict prognosis of GC patients who received PF-based therapy.

Genetic polymorphism of rs9564966 G > A on 13q22.1 predicts poor survival for Chinese patients with gastric cancer

Two genomewide association studies on pancreatic cancer have identified a novel single‐nucleotide polymorphism of rs9564966 G > A on 13q22.1 region. However, the associations between the rs9564966 G > A polymorphism and the survival of Chinese patients with gastric cancer (GC) were unknown. In our present investigation, we adopted the Kaplan‐Meier plots, Cox regression analyses, and the log‐rank tests to explore the associations between rs9564966 G > A polymorphism and the prognosis of 911 Chinese patients with GC. Our results revealed that, compared with GG genotype, patients with GA + AA genotypes had poorer outcomes (HR = 1.348, 95% CI = 1.084‐1.675, P = 0.007), especially in the subgroups of age ≤60 years, male, nondrinker, tumor size >5 cm, tumor site in Noncardia, intestinal‐type tumor, T3/T4 level depth of invasion, N1/N2/N3 level lymph node metastasis, no distant metastasis, III/IV level TNM stages, and no chemotherapy. Our findings suggested that the rs9564966 G > A polymorphism may be a potential biomarker to predict the survival of Chinese patients with GC.