Updated assessment of the association of the XRCC1 Arg399Gln polymorphism with lung cancer risk in the Chinese population

Association of genetic polymorphisms in DNA repair genes ERCC2 Asp312Asn (rs1799793), ERCC2 Lys 751 Gln (rs13181), XRCC1 Arg399 Gln (rs25487) and XRCC3 Thr 241Met (rs861539) with the susceptibility of lung cancer in Saudi population

This study demonstrated the association of polymorphisms in ERCC2 (Asp312Asn) rs1799793, ERCC2 (Lys751Gln) rs13181, XRCC1 (Arg399Gln) rs25487 and XRCC3(Thr241Met) rs861539 polymorphisms with a susceptibility of lung cancer (LC) onset in the Saudi population. The study was performed on 134 LC patients and 270 controls. The data revealed that there was no significant association of LC with subtype squamous cell carcinoma (SCC), small cell lung cancer (SCLC) and adenocarcinoma with the ERCC2 rs1799793 polymorphism. The data showed that the CC genotype for ERCC2 rs13181, the AA genotype for XRCC1 rs25487, and the genotype TT for XRCC3 rs861539 were significantly associated with SCC susceptibility (p < 0.05). Similarly, the CC genotype for ERCC2 rs13181 and the AA genotype for XRCC1 rs25487 were significantly associated with adenocarcinoma susceptibility (p < 0.05). Whereas, the TT genotype for XRCC3 rs861539 was significantly associated with SCLC susceptibility (p = 0.005). In total, significant association of LC susceptibility was found in the following combination models of recessive genotypes: AC heterozygous for ERCC2 rs13181 + AA homozygous for XRCC1 rs25487, CC homozygous for ERCC2 rs13181 + GA heterozygous for rs25487, CC homozygous for rs13181 + AA homozygous for XRCC1 rs25487, CC homozygous for ERCC2 rs13181 + TT homozygous for XRCC3 rs861539, GA heterozygous for XRCC1 rs25487 + CT heterozygous for XRCC3 rs861539, GA heterozygous for XRCC1 rs25487 + TT homozygous for XRCC3 rs861539, AA homozygous for XRCC1 rs25487 + CT heterozygous for XRCC3 rs861539, AA homozygous for XRCC1 rs25487+ TT homozygous for XRCC3 rs861539. These data clearly demonstrated that the combination of recessive genotypes may be associated with susceptibility of LC onset (p < 0.05). In short, the data indicated that DNA repair genes increase LC risk via gene-gene interaction rather than independent variants.

The modulation of oxidative stress and DNA damage to radiology technicians by repair enzymes XRCC1 and XRCC3 The association of oxidative stress and DNA damage with XRCC1 and XRCC3 polymorphisms in radiology technicians

Ionizing radiation has widespread use in medicine in the diagnosis and treatment of many medical conditions. Radiology technicians are one group that is occupationally exposed to low doses of radiation. There are questions regarding whether low dose exposure to radiation could have long-term health consequences. Assessing the effect of radiation on genetic material is essential for appraising long-term health results. Hereditary variations in DNA repair genes cause differentiation in individual responses to radiation related health effects. This study aimed to determine oxidative stress and DNA damage, and their relationship to XRCC1 (Arg399Gln) and XRCC3 (Thr241Met) polymorphisms in radiology technicians occupationally exposed to low dose radiation. Peripheral blood samples were collected from 45 radiology technicians and age-matched with 40 healthy control individuals working in office environments. Our results showed that radiology technicians had significantly greater oxidative stress and DNA damage than the control group, and women appeared more susceptible to occupational radiation exposure than men. Individuals with wild-type genotypes for XRCC1 (Arg/Arg) and XRCC3 (Thr/Thr) had less DNA damage. Lower DNA damage levels could be explained by the enhanced capacity to repair low dose radiation induced DNA damage. Further studies are needed to evaluate the role of DNA repair genes in individuals that are occupationally exposed to low dose radiation.

CYP3A4 genetic variants are associated with susceptibility of non-small cell lung cancer in a Shaanxi Han population

PURPOSE

Lung cancer (LC) is one of the fastest-growing malignant tumors in the world in terms of morbidity and mortality. CYP3A4 plays a crucial role in the occurrence of LC. Little is known about the contribution of CYP3A4 polymorphisms for non-small cell lung cancer (NSCLC) risk. This study aimed to explore the correlation of CYP3A4 genetic variants (rs3735451, rs4646440, rs35564277, and rs4646437) with NSCLC risk.

METHODS

Four single nucleotide polymorphisms (SNPs) were genotyped by Agena MassARRAY in this case-control study (507 NSCLC patients and 505 controls) among a Shaanxi Han population. Hardy-Weinberg equilibrium (HWE) of each SNP in controls was evaluated by exact test. The association of CYP3A4 polymorphisms with NSCLC risk was explored by calculating odds ratios (OR) and 95% confidence intervals (CI) using logistic regression analysis with adjustment for age and gender.

RESULTS

Our research revealed that rs4646440 was significantly associated with an increased risk of NSCLC (OR 2.64, p = .005), while rs4646437 played a protective role in NSCLC risk (OR 0.48, p = 4.00 × 10^-7). Stratified analyses indicated that rs4646440 significantly enhanced the susceptibility of NSCLC in BMI > 24 kg/m², non-smokers and non-drinkers (OR 14.29, p = .012; OR 1.56, p = .023; OR 1.67, p = .031, respectively). Besides, we observed that rs3735451 exhibited an increased risk of NSCLC in BMI > 24 kg/m² (OR 2.47, p = .030), whereas rs4646437 had a reduced risk of NSCLC in BMI ≤ 24 kg/m² (OR 0.47, p = 5.17 × 10^-5). We also found that rs35564277 was considered as a protective factor of NSCLC in non-smokers (OR 0.50, p = .032).

CONCLUSION

Our study indicated that CYP3A4 genetic variants were associated with NSCLC susceptibility in a Shaanxi Han population.

Common polymorphisms of the hOGG1, APE1 and XRCC1 genes correlate with the susceptibility and clinicopathological features of primary angle-closure glaucoma

The present case study aims to elucidate the correlation between the human 8-hydroxyguanineglycosylase (hOGG1), APE1 and X-ray repair cross-complementing gene 1 (XRCC1) gene polymorphisms to the susceptibility and clinicopathological features of primary angle closure glaucoma (PACG) in a Chinese Han population. Blood samples were obtained from 258 PACG patients (case group) and 272 healthy volunteers (control group). PCR with sequence-specific primer (PCR-SSP) was used to determine the allele frequencies and genotype distributions of the hOGG1, APE1 and XRCC1 genes. The risk factors of PACG were determined using logistic regression analysis. The results indicated that hOGG1 Ser326Cys, APE1 Asp148Glu and XRCC1 Arg399Gln polymorphisms were correlated with the risk of PACG. Furthermore, there were thicker corneas, higher intraocular pressure (IOP) and a shorter axial length in patients carrying the mutant genotypes of hOGG1 Ser326Cys (Ser/Cys + Cys/Cys), APE1 Asp148Glu (Asp/Glu + Glu/Glu) and XRCC1 Arg399Gln (Arg/Gln + Glu/Glu) than those carrying the corresponding wild-type genotypes. According to the logistic regression analysis, Asp148Glu and Arg399Gln polymorphisms, a short axial length and high IOP are major risk factors for PACG. These findings reveal that hOGG1 Ser326Cys, APE1 Asp148Glu and XRCC1 Arg399Gln polymorphisms are correlated with the risk and clinicopathological features of PACG in a Chinese Han population.

Contribution of Macrophage Migration Inhibitory Factor -173G/C Gene Polymorphism to the Risk of Cancer in Chinese Population

BACKGROUND

Macrophage migration inhibitory factor (MIF) -173G/C (rs755622) gene polymorphism has been associated with cancer risk. Previous studies have revealed that MIF -173G/C gene polymorphism may increase cancer in the Chinese population, while results of individual published studies remain inconsistent and inconclusive.We performed this meta-analysis to derive a more precise estimation of the relationship.

MATERIALS AND METHODS

We conducted a search on PubMed, Embase, MEDLINE, Cochrane Library ,Chinese National Knowledge Infrastructure (CNKI), Wanfang, Weipu on Dec 31, 2014.Odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the association. A total of eight studies including 2,186 cases and 2,285 controls were involved in this meta-analysis.

RESULTS

The pooled results indicated the significant association between MIF -173G/C polymorphism and the risk of cancer for Chinese population (CC + CG vs GG: OR=1.14, 95%CI=1.02-127, pheterogeneity<0.01; P =0.023; CC vs CG+GG: OR=1.12, 95%CI=1.02- 1.23, pheterogeneity< 001; P =0.017;CC vs GG: OR=1.18, 95%CI=1.04-1.33, pheterogeneity<001; P =0.008; CG vs GG:OR=1.03, 95%CI=0.91-1.15, pheterogeneity<001; P =0.656; C vs G:OR=1.24, 95%CI=1.14-1.25, pheterogeneity<001; P <001). Subgroup analysis showed that in patients with "solid tumors", heterogeneity was very large (OR=0.94,95%CI=0.83-1.06,pheterogeneity=0.044; p=0.297). Within "non-solid tumors", the association became even stronger (OR=6.62, 95 % CI=4.32-10.14, pheterogeneity<0.001; p <0.001).

CONCLUSIONS

This study suggested that MIF ?173G/C gene polymorphism may increase increase cancer in the Chinese population.Furthermore, more larger sample and representative population-based casees and well-matched controls are needed to validate our results.