Original Article SOD2 rs4880 CT/CC genotype predicts poor survival for Chinese gastric cancer patients received platinum and fluorouracil based adjuvant chemotherapy

Abstract: Adjuvant chemotherapy is a standard therapy for gastric cancer patients, however, treatment response is quite heterogeneous. Molecular biomarkers will be highly valuable to guide the therapy and predict the response and prognosis in these patients. The antioxidant enzymes superoxide dismutase 2 (SOD2) and glutathione S-transferase pi 1 (GSTP1) are involved in oxidative stress and drug detoxification, which modulate the efficacy of anticancer drugs. Here, we investigated the clinical associations of two functional single nucleotide polymorphisms of SOD2 and GSTP1 in stage II-III postoperative gastric cancer patients. SOD2 rs4880 and GSTP1 rs1695 were genotyped in 207 patients received postoperative platinum and fluorouracil based chemotherapy and 304 patients who did not. SOD2 rs4880 CT/CC significantly associated with decreased median overall survival time of 23 months when compared to the TT genotype (mean overall survival time of 65.2 months, P=0.002) only for patients received adjuvant chemotherapy. Stratification analysis showed SOD2 rs4880 C

Association of Antioxidative Enzymes Polymorphisms with Efficacy of Platin and Fluorouracil-Based Adjuvant Therapy in Gastric Cancer

Background/Aims: Imbalance of oxidative/antioxidative enzymes in cells is associated with carcinogenesis and cancer cell chemoresistance. The aim of this study was to examine the clinical significance of potentially functional single nucleotides polymorphisms (SNPs) in antioxidative enzymes, GPxs and CAT, in stages II and III gastric cancer patients. Methods: A total of 591 gastric cancer patients who had radical gastrectomy were recruited. 207 patients received platinum and fluorouracil-based (PF-based) adjuvant chemotherapy and 384 patients were untreated. GPx1 rs1050450, GPx2 rs4902346, GPx3 rs736775, rs3828599 and CAT rs769218 were genotyped in the DNA samples extracted from paraffin-embedded tumor tissue. Results: CAT rs769218 was significantly correlated with the overall survival (OS) in the dominant model (P = 0.014). Multivariate analysis revealed that CAT rs769218 GA/AA (HR, 0.715; 95%CI, 0.562-0.910, P = 0.006) was an independent prognostic marker indicating improved survival. After adjustments, GPx3 rs736775 TC/CC was significantly associated with improved OS (HR, 0.621; 95%CI, 0.399-0.965; P=0.034) in patients treated with PF-based adjuvant chemotherapy, and CAT rs769218 GA/AA was significantly associated with improved OS (HR, 0.646; 95% CI, 0.482-0.864; P = 0.003) in the untreated patients. PF-based chemotherapy significantly decreased risk of death for patients carrying GPx3 rs736775 TC/CC and age ≤ 60 years or with diffused type adenocarcinoma compared to surgery alone. Conclusion: our findings suggested CAT rs769218 and GPx3 rs736775 may be considered as prognostic markers in gastric cancer. Patient stratification by GPx3 rs736775 and conventional pathological parameters may provide additional predictive information in treatment decision-making

The DNA Repair Gene APE1 T1349G Polymorphism and Risk of Gastric Cancer in a Chinese Population

Background: Apurinic/apyrimidinic endonuclease 1 (APE1) has a central role in the repair of apurinic apyrimidic sites through both its endonuclease and its phosphodiesterase activities. A common APE1 polymorphism, T1349G (rs3136820), was previously shown to be associated with the risk of cancers. Objective: We hypothesized that the APE1 T1349G polymorphism is also associated with risk of gastric cancer. Methods: In a hospital-based case-control study of 338 case patients with newly diagnosed gastric cancer and 362 cancerfree controls frequency-matched by age and sex, we genotyped the T1349G polymorphism and assessed its associations with risk of gastric cancer. Results: Compared with the APE1 TT genotype, individuals with the variant TG/GG genotypes had a significantly increased risk of gastric cancer (odds ratio = 1.69, 95 % confidence interval = 1.19–2.40), which was more pronounced among subgroups of aged #60 years, male, ever smokers, and ever drinkers. Further analyses revealed that the variant genotypes were associated with an increased risk for diffuse-type, low depth of tumor infiltration (T1 and T2), and lymph node metastasis gastric cancer. Conclusions: The APE1 T1349G polymorphism may be a marker for the development of gastric cancer in the Chinese population. Larger studies are required to validate these findings in diverse populations

Effects of MCF2L2, ADIPOQ and SOX2 genetic polymorphisms on the development of nephropathy in type 1 Diabetes Mellitus

<p>Abstract</p> <p>Background</p> <p><it>MCF2L2, ADIPOQ </it>and <it>SOX2 </it>genes are located in chromosome 3q26-27, which is linked to diabetic nephropathy (DN). <it>ADIPOQ </it>and <it>SOX2 </it>genetic polymorphisms are found to be associated with DN. In the present study, we first investigated the association between <it>MCF2L2 </it>and DN, and then evaluated effects of these three genes on the development of DN.</p> <p>Methods</p> <p>A total of 1177 type 1 diabetes patients with and without DN from the GoKinD study were genotyped with TaqMan allelic discrimination. All subjects were of European descent.</p> <p>Results</p> <p>Leu359Ile T/G variant in the <it>MCF2L2 </it>gene was found to be associated with DN in female subjects (P = 0.017, OR = 0.701, 95%CI 0.524-0.938) but not in males. The GG genotype carriers among female patients with DN had tendency decreased creatinine and cystatin levels compared to the carriers with either TT or TG genotypes. This polymorphism <it>MCF2L2-</it>rs7639705 together with SNPs of <it>ADIPOQ</it>-rs266729 and <it>SOX2</it>-rs11915160 had combined effects on decreased risk of DN in females (P = 0.001).</p> <p>Conclusion</p> <p>The present study provides evidence that <it>MCF2L2</it>, <it>ADIPOQ </it>and <it>SOX2 </it>genetic polymorphisms have effects on the resistance of DN in female T1D patients, and suggests that the linkage with DN in chromosome 3q may be explained by the cumulated genetic effects.</p

Evaluation of the association between the common E469K polymorphism in the ICAM-1 gene and diabetic nephropathy among type 1 diabetic patients in GoKinD population

<p>Abstract</p> <p>Background</p> <p>The ICAM-1 gene is a strong positional and biological candidate for susceptibility to the development of T1D and DN. We have recently demonstrated that SNP rs5498(E469K) confers susceptibility to the development of T1D and might be associated with DN in Swedish Caucasians. The present study aimed to further evaluate the association between the ICAM-1 genetic polymorphisms and DN.</p> <p>Methods</p> <p>Two common non-synonymous SNPs, including rs5498(E469K) and rs1799969(R241G), in the ICAM-1 gene were genotyped in 662 (312 female/350 male) T1D patients with DN and 620 (369/251) without DN. All patients were selected from the GoKinD study.</p> <p>Results</p> <p>Genotype distributions of both SNPs were in Hardy-Weinberg equilibrium but SNP rs5498(E469K) had high heterozygous index. In this SNP, the heterozygosity and positivity for the allele G were found to be significantly associated with DN in female T1D patients (P = 0.010, OR = 0.633, CI 95% 0.447–0.895 and P = 0.026, OR = 0.692, CI 95% 0.500–0.958). Furthermore, the female patients without DN carrying three genotypes A/A, A/G and G/G had different cystatin levels (0.79 ± 0.17, 0.81 ± 0.14 and 0.75 ± 0.12 mg/L, P = 0.021). No significant association of SNP rs1799969 (R241G) with DN was found.</p> <p>Conclusion</p> <p>The present study provides further evidence that SNP rs5498(E469K) in the ICAM-1 gene presents a high heterozygous index and the allele G of this polymorphism may confers the decreased risk susceptibility to the development of DN in female T1D patients among the GoKinD population.</p

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead