Associations of Lys939Gln and Ala499Val polymorphisms of the XPC gene with cancer susceptibility: a meta-analysis

Genetic variants in XPD gene and glioma susceptibility in Chinese children: A multicenter case-control study

Background

Glioma is one of the central nervous system (CNS) tumors in children, accounting for 80% of malignant brain tumors. Nucleotide excision repair (NER) is a vital pathway during DNA damage repair progression. Xeroderma pigmentosum group D (XPD) or excision repair cross-complementing group 2 (ERCC2) is a critical factor in the NER pathway, playing an indispensable role in the DNA repair process. Therefore, the genetic variants in XPD may be associated with carcinogenesis induced by defects in DNA repair.

Methods

We are the first to conduct a multi-center case-control study to investigate the correlation between XPD gene polymorphisms and pediatric glioma risk. We chose three single nucleotide polymorphisms and genotyped them using the TaqMan assay.

Results

Although there is no significant association of these genetic variations with glioma susceptibility, the stratified analysis revealed that in the subtype of astrocytic tumors, the rs13181 TG/GG genotype enhanced glioma risk than the TT genotype, and carriers with two to three genotypes also elevated the tumor risk than 0-1 genotypes.

Conclusion

In conclusion, our findings provided an insight into the impact of XPD genetic variants on glioma risk.

Oxidative Damage in Sporadic Colorectal Cancer: Molecular Mapping of Base Excision Repair Glycosylases MUTYH and hOGG1 in Colorectal Cancer Patients

Oxidative stress, oxidative DNA damage and resulting mutations play a role in colorectal carcinogenesis. Impaired equilibrium between DNA damage formation, antioxidant status, and DNA repair capacity is responsible for the accumulation of genetic mutations and genomic instability. The lesion-specific DNA glycosylases, e.g., hOGG1 and MUTYH, initiate the repair of oxidative DNA damage. Hereditary syndromes (MUTYH-associated polyposis, NTHL1-associated tumor syndrome) with germline mutations causing a loss-of-function in base excision repair glycosylases, serve as straight forward evidence on the role of oxidative DNA damage and its repair. Altered or inhibited function of above glycosylases result in an accumulation of oxidative DNA damage and contribute to the adenoma-adenocarcinoma transition. Oxidative DNA damage, unless repaired, often gives rise G:C > T:A mutations in tumor suppressor genes and proto-oncogenes with subsequent occurrence of chromosomal copy-neutral loss of heterozygosity. For instance, G>T transversions in position c.34 of a KRAS gene serves as a pre-screening tool for MUTYH-associated polyposis diagnosis. Since sporadic colorectal cancer represents more complex and heterogenous disease, the situation is more complicated. In the present study we focused on the roles of base excision repair glycosylases (hOGG1, MUTYH) in colorectal cancer patients by investigating tumor and adjacent mucosa tissues. Although we found downregulation of both glycosylases and significantly lower expression of hOGG1 in tumor tissues, accompanied with G>T mutations in KRAS gene, oxidative DNA damage and its repair cannot solely explain the onset of sporadic colorectal cancer. In this respect, other factors (especially microenvironment) per se or in combination with oxidative DNA damage warrant further attention. Base excision repair characteristics determined in colorectal cancer tissues and their association with disease prognosis have been discussed as well.

Development of a custom next-generation sequencing panel for the determination of bladder cancer risk in a Tunisian cohort

BACKGOUND

Bladder cancer (BCa) is a heterogeneous disease caused by the interaction between environmental and genetic risk factors. The goal of this case-control study was to evaluate the implication of a selected SNP panel in the risk of BCa development in a Tunisian cohort. We were also interested in studying the interaction between this predictive panel and environmental risk factors.

METHODS

The case/control cohort was composed with 249 BCa cases and 255 controls. The designed Bladder cancer hereditary panel (BCHP) was composed of 139 selected variants. These variants were genotyped by an amplification-based targeted Next-Generation Sequencing (NGS) on the Ion Torrent Proton sequencer (Life Technologies, Ion Torrent technology).

RESULTS

We have found that rs162555, rs2228000, rs10936599, rs710521, rs3752645, rs804276, rs4639, rs4881400 and rs288980 were significantly associated with decreased risk of bladder cancer. However the homozygous genotypes for VPS37C (rs7104333, A/A), MPG (rs1013358, C/C) genes or the heterozygous genotype for ARNT gene (rs1889740, rs2228099, rs2256355, rs2864873), GSTA4 (rs17614751) and APOBR/IL27 (rs17855750) were significantly associated with increased risk of bladder cancer development compared to reference group (OR 2.53, 2.34, 1.99, 2.00, 2.00, 1.47, 1.96 and 2.27 respectively). We have also found that non-smokers patients harboring heterozygous genotypes for ARNT/rs2864873 (A > G), ARNT/ rs1889740 (C > T) or GSTA4/rs17614751 (G-A) were respectively at 2.775, 3.069 and 6.608-fold increased risk of Bca development compared to non-smokers controls with wild genotypes. Moreover the ARNT CT (rs1889740), ARNT CG (rs2228099), ARNT TC (rs2864873) and GSS GA genotypes were associated with an increased risk of BCa even in absence of professional risk factors. Finally the decision-tree analysis produced a three major BCa classes. These three classes were essentially characterized by an intensity of tobacco use more than 20 pack years (PY) and the CYP1A2 (rs762551) genotype.

CONCLUSIONS

The determined association between environmental factors, genetic variations and the risk of Bca development may provide additional information to urologists that may help them for clinical assessment and treatment decisions. Nevertheless, the underlying mechanisms through which these genes or SNPs affect the clinical behavior of BCas require further studies.

Smoking and XPC Gene Polymorphism Interact to Modulate the Risk of Oral Cancer

Purpose

Oral cancer is the most common cancer among the Indian men and the second most common cancer among the Indian women. Such high incidence of oral cancer in India is due to consumption of tobacco in different form including smoking of cigarette. Smoke of tobacco contains different carcinogens which causes DNA damage. Such DNA damage if remain unrepaired due to faulty DNA repair system can cause mutation and eventual development of cancer.

Methodology

In the present study, we aimed to check the role of smoking as well as interaction of smoking and XPC polymorphism in risk modulation of oral cancer. Total of 372 subjects including 300 healthy controls and 72 patients of oral cancers been genotyped for the XPC PAT D/I, A/C and C/T polymorphisms with PCR based or PCR-RFLP based method. Genotype frequency was analyzed by chi-square test and strength of associations by odds ratio with 95% confidence intervals.

Results

The present study showed that compared to nonsmokers, smokers are at five times higher risk to develop oral cancer (p value= 0.001, OR= 5.03, 95% CI 2.91-8.69) and three times higher risk to develop node-positive (p value= 0.01, OR= 3.66, 95% CI 1.34-9.95) oral cancer. It has also been observed that individuals who were smokers and carrier of variant allele genotypes (AC and CC) for XPC A/C polymorphism were at threefold higher risk (p value= 0.01, OR=2.97, 95% CI 1.29-6.86) to develop oral cancer compared to individual who were smokers but do not carry the C allele (AA genotype). This observation indicates that C allele of XPC A/C polymorphism interacts with smoking and significantly increases the risk of oral cancer.

Conclusion

This study demonstrates a possible role of smoking and gene-smoking interaction in risk enhancement of oral cancer.

Xeroderma pigmentosum and acute myeloid leukemia: a case report

BACKGROUND

Xeroderma pigmentosum is a rare inherited disease characterized by extreme hypersensitivity to ultraviolet rays and predisposing to cutaneous malignancies that can appear in childhood. These manifestations are often associated with ocular lesions and sometimes with neurological disorders. The association of xeroderma pigmentosum with internal neoplasms such as acute myeloblastic leukemia is not reported with great frequency, which confirms the rarity of this occurrence.

CASE REPORT

A 26-year-old Moroccan women, xeroderma pigmentosum patient, was diagnosed with acute myeloblastic leukemia with a complex karyotype. Due to the adverse risk of the xeroderma pigmentosum association with acute myeloblastic leukemia and the profile of acute myeloblastic leukemia with complex karyotype and monosomy 7, which constitute factors of poor prognosis, as well as the absence of studies conceding the tolerance of the chemotherapy by patients suffering from xeroderma pigmentosum, our patient was put under low-dose cytarabine protocol with granulocyte colony-stimulating factor. Unfortunately, she died on the tenth day of chemotherapy by acute pulmonary edema of cardiogenic pace complicated by tamponade.

CONCLUSION

According to reports, it is the second case showing association of xeroderma pigmentosum with acute myeloblastic leukemia. The management of these patients remains a challenge. Studies focusing on xeroderma pigmentosum patients developing hematological malignancies are necessary to better understand the most appropriate strategies and precautions for this specific case.

Interaction of DNA Repair Gene XPC With Smoking and Betel Quid Chewing Behaviors of Oral Cancer

BACKGROUND/AIM

Xeroderma pigmentosum complementation group C (XPC) is reported to play important roles in DNA integrity and genomic instability, however, the contribution of XPC to oral carcinogenesis is largely uncertain. Therefore, we aimed at examining the contribution of XPC genotypes to oral cancer.

MATERIALS AND METHODS

The genotypes of XPC rs2228001 and rs2228000 were examined among 958 oral cancer patients and 958 control subjects by polymerase chain reaction-restriction fragment length polymorphism methodology and corresponding DNA repair capacity was checked.

RESULTS

First, the percentages of XPC rs2228001 AC and CC were higher among oral cancer patients than controls. Second, no significant association was observed regarding XPC rs2228000. Third, there was a synergistic influence of smoking and betel quid chewing behaviors and XPC rs2228001 genotype on oral cancer risk. Last, functional experiments showed DNA repair capacity was lower for AC/CC carriers than AA carriers.

CONCLUSION

XPC rs2228001 C allele, which was associated with decreased DNA repair capacity, may interact with smoking and betel quid chewing behaviors on oral cancer risk.

Association of DNA repair gene XPC Ala499Val (rs2228000 C>T) and Lys939Gln (rs2228001 A>C) polymorphisms with the risk of chronic myeloid leukemia: A case-control study in a South Indian population

BACKGROUND

Xeroderma pigmentosum complementation group C (XPC), a DNA repair protein, plays an important role in the maintenance of genomic integrity and is essential for the nucleotide excision repair pathway. Polymorphisms in the XPC gene may alter DNA repair leading to genetic instability and oncogenesis. The present study aimed to assess the relationship between the XPC Ala499Val (rs2228000 C>T) and Lys939Gln (rs2228001 A>C) non-synonymous polymorphisms and susceptibility to chronic myeloid leukemia (CML) pathogenesis, disease progression and the response to targeted therapeutic regimen, imatinib mesylate.

METHODS

This case-control study included 212 cases and 212 controls, and the genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism assays.

RESULTS

Our results showed significant association of variant CT (odds ratio = 1.92, 95% confidence interval = 1.21-3.06, p = 0.003) and TT (odds ratio = 2.84, 95% confidence interval = 1.22-6.71, p = 0.007) genotypes in patients with the XPC Ala499Val polymorphism and CML risk. In addition, these genotypes were associated with CML progression to advanced phases (p = 0.006), splenomegaly (p = 0.017) and abnormal lactate dehydrogenase levels (p = 0.03). XPC Lys939Gln was found to correlate with a poor response to therapy, showing borderline significant association with minor cytogenetic response (p = 0.08) and a poor molecular response (p = 0.06). Significant association of the Ala499Val and Lys939Gln polymorphisms with prognosis was observed (Hasford high risk, p = 0.031 and p = 0.019, respectively). Haplotype analysis showed a strong correlation of variant TC haplotype with poor therapy responses (minor cytogenetic response, p = 0.019; poor molecular response, p < 0.0001).

CONCLUSIONS

In conclusion, our results suggest that XPC Ala499Val is a high-penetrance CML susceptibility polymorphism. Both polymorphisms studied are considered as genetic markers with respect to assessing disease progression, therapy response and prognosis in CML patients.

The ECCR1 rs11615, ERCC4 rs2276466, XPC rs2228000 and XPC rs2228001 polymorphisms increase the cervical cancer risk and aggressiveness in the Bangladeshi population

Background

Multiple studies around the world revealed that genetic polymorphism in different genes of the DNA repair system might affect the DNA repair capabilities and accelerate the chances of cervical cancer (CC) development. Therefore, we aimed to evaluate the association of DNA repair gene- ECCR1 rs11615, ERCC4 rs2276466, XPC rs2228000 and rs2228001 polymorphisms and CC susceptibility in the Bangladeshi population.

Methods

A case-control genetic association study was conducted among 210 patients with diagnostically confirmed CC and 200 healthy volunteers. The p-value and OR (odds ratios) with 95% CI (confidence interval) were evaluated to get the level of association.

Results

After the individual analysis of all SNPs, we noticed that ECCR1 rs11615 possessed a significantly lower risk, whereas ERCC4 rs2276466 possessed a significantly elevated risk of CC in all genetic models (p < 0.05). XPC rs2228000 showed a significantly lower risk of CC in TC, TC + CC genotypes and allele model (OR = 0.61, p = 0.025; OR = 0.61, p = 0.019 and OR = 0.67, p = 0.027, respectively), whereas XPC rs2228001 possessed a significantly elevated risk of CC in CA, CA + AA genotypes and allele model (OR = 1.67, p = 0.012; OR = 1.69, p = 0.009 and OR = 1.42, p = 0.022). Besides, ERCC4 rs2276466 (Grade III vs. I + II: OR = 4.01, p = 0.003) and XPC rs2228001 (Grade III vs. I + II: OR = 3.38, p = 0.003) were connected with high tumor aggressiveness and ERCC4 rs2276466 was also showed a lower risk of CC development in the younger population (<45 years).

Conclusion

The findings supported that rs2276466 and rs2228001 polymorphisms increase CC development and aggressiveness, whereas rs11615 and rs2228000 lower the CC risk in the studied population.

Comprehensive assessment of the association between XPC rs2228000 and cancer susceptibility based on 26835 cancer cases and 37069 controls

Objectives In the present study, we examined available articles from online databases to comprehensively investigate the effect of the XPC (xeroderma pigmentosum complementation group C) rs2228000 polymorphism on the risk of different types of clinical cancer.

Methods We conducted a group of overall and subgroup pooling analyses after retrieving the data from four databases (updated till September 2019). The P-value of association, OR (odds ratios), and 95% CI (confidence interval) were calculated.

Results We selected a total of 71 eligible studies with 26835 cancer cases and 37069 controls from the 1186 retrieved articles. There is an enhanced susceptibility for bladder cancer cases under T vs. C [P=0.004; OR (95% CI) = 1.25 (1.07, 1.45)], TT vs. CC [P=0.001; 1.68 (1.25, 2.26)], CT+TT vs. CC [P=0.016; 1.26 (1.04, 1.53)], and TT vs. CC+ CT [P=0.001; 1.49 (1.18, 1.90)] compared with negative controls. Additionally, there is an increased risk of breast cancer under T vs. C, TT vs. CC and TT vs. CC+ CT (P<0.05, OR > 1). Nevertheless, there is a decreased risk of gastric cancer cases in China under T vs. C [P=0.020; 0.92 (0.85, 0.99)], CT vs. CC [P=0.001, 0.83 (0.73, 0.93)], and CT+TT vs. CC [P=0.003, 0.84 (0.76, 0.94)].

Conclusions The TT genotype of XPC rs2228000 may be linked to an increased risk of bladder and breast cancer, whereas the CT genotype is likely to be associated with reduced susceptibility to gastric cancer in the Chinese population.

XPC exon15 Lys939Gln variant increase susceptibility to prostate adenocarcinoma: Evidence based on 4306 patients and 4779 controls

BACKGROUND

Previous studies have investigated the correlation between xeroderma pigmentosumcomplementation group C (XPC) variants and prostate adenocarcinoma (PA) risk. Nevertheless, research findings remain inconclusive.

METHODS

We conducted a pooled analysis to obtain a more accurate estimation of the relationship on XPC exon15 Lys939Gln polymorphism with susceptibility to PA. Moreover, in silico tools were employed to investigate the effect of XPC expression on PA patients' survival time.

RESULTS

A total of 4306 patients and 4779 control subjects were assessed. The overall results indicated that XPC Lys939Gln variant was associated with PA risk (recessive genetic model: odds ratio = 1.15, 95% confidence interval = 1.02-1.30, Pheterogeneity= .044, P = .021, I= 45.2), especially in Asian descendants. Population-based studies revealed similar results (odds ratio = 1.15, 95% confidence interval = 1.01-1.32, Pheterogeneity= .146, P = .040, I = 39.0). In silico tools showed that XPC expression in Caucasian patients was lower than in the normal group. No positive association was observed in African patients. PA subjects with high XPC expression had a longer overall survival time than low expression group.

CONCLUSION

Our findings indicated that XPC Lys939Gln variant might contribute to increased PA susceptibility, especially for Asian patients.

Effects of Xeroderma pigmentosum group C polymorphism on the likelihood of prostate cancer

Background

Numerous studies have assessed the association between xeroderma pigmentosum complementation group C (XPC) polymorphisms and susceptibility of prostate cancer (PCa); however, the findings remain inconsistent.

Methods

We performed an updated analysis utilizing data from electronic databases to obtain a more accurate estimation of the relationship between XPC rs2228001 A/C polymorphism and PCa risk. We further used in silico tools to investigate this correlation.

Results

Totally, 5,305 PCa cases and 6,499 control subjects were evaluated. When all studies pooled together, we detected no positive result (recessive genetic model: OR = 1.14, 95% CI = 0.93‐1.40, P_{heterogeneity} = 0.001, P = .212); nevertheless, the XPC rs2228001 A/C variant was associated with PCa risk in Asian descendants in the subgroup analysis (OR = 1.21, 95% CI = 1.01‐1.43, P_{heterogeneity} = 0.008, P = .034). In silico tools showed that more than 20 proteins can participate in the protein crosstalk with XPC. The expression of XPC was down‐regulated in all Gleason scores of prostate cancer.

Conclusions

The present study indicated that the XPC rs2228001 A/C variant may be associated with elevated PCa risk in Asian patients.

Oxidative Damage in Sporadic Colorectal Cancer: Molecular Mapping of Base Excision Repair Glycosylases in Colorectal Cancer Patients

Oxidative stress with subsequent premutagenic oxidative DNA damage has been implicated in colorectal carcinogenesis. The repair of oxidative DNA damage is initiated by lesion-specific DNA glycosylases (hOGG1, NTH1, MUTYH). The direct evidence of the role of oxidative DNA damage and its repair is proven by hereditary syndromes (MUTYH-associated polyposis, NTHL1-associated tumor syndrome), where germline mutations cause loss-of-function in glycosylases of base excision repair, thus enabling the accumulation of oxidative DNA damage and leading to the adenoma-colorectal cancer transition. Unrepaired oxidative DNA damage often results in G:C>T:A mutations in tumor suppressor genes and proto-oncogenes and widespread occurrence of chromosomal copy-neutral loss of heterozygosity. However, the situation is more complicated in complex and heterogeneous disease, such as sporadic colorectal cancer. Here we summarized our current knowledge of the role of oxidative DNA damage and its repair on the onset, prognosis and treatment of sporadic colorectal cancer. Molecular and histological tumor heterogeneity was considered. Our study has also suggested an additional important source of oxidative DNA damage due to intestinal dysbiosis. The roles of base excision repair glycosylases (hOGG1, MUTYH) in tumor and adjacent mucosa tissues of colorectal cancer patients, particularly in the interplay with other factors (especially microenvironment), deserve further attention. Base excision repair characteristics determined in colorectal cancer tissues reflect, rather, a disease prognosis. Finally, we discuss the role of DNA repair in the treatment of colon cancer, since acquired or inherited defects in DNA repair pathways can be effectively used in therapy.

Association of XPC Polymorphisms with Cutaneous Malignant Melanoma Risk: Evidence from a Meta-Analysis

BACKGROUND

A number of studies have reported that the xeroderma pigmentosum complementation group C (XPC) polymorphisms are associated with cutaneous malignant melanoma (CMM) susceptibility. But the results of those studies were inconsistent. Here, we performed a study to obtain a more conclusive result on the association of XPC polymorphisms with risk of CMM.

METHODS

The XPC Lys939Gln and Ala499Val polymorphisms were genotyped in 150 CMM cases and 150 controls by PCR-RFLP assay. Subsequently, all published relevant studies were identified through a comprehensive literature search in PubMed, Web of Science, and CNKI databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of correlation.

RESULTS

There was no significant association between XPC Lys939Gln and Ala499Val polymorphisms and CMM risk in our population. A total of 15 case-control studies including ten studies with 5,990 cases and 7,697 controls on XPC Lys939Gln and five studies with 3,139 cases and 3,721 controls on XPC Ala499Val polymorphism were selected. Pooled data revealed that XPC Lys939Gln (C vs. A: OR = 1.108, 95% CI 1.008- 1.217; P = 0.033) and Ala499Val (C vs. A: OR = 0.918, 95% CI 0.850-0.992; p = 0.031; CC+CA vs. AA: OR = 0.904, 95% CI 0.819-0.997; p = 0.043) polymorphisms were significantly associated with an increased risk of CMM. Moreover, stratified analyses by ethnicity revealed that the XPC Ala499Val and Lys939Gln polymorphisms were significantly associated with risk of CMM in Caucasians and mixed populations, respectively.

CONCLUSIONS

This meta-analysis result suggested that XPC Lys939Gln and Ala499Val polymorphisms were significantly associated with risk of CMM.

Polymorphisms in XPC Gene and Risk of Uterine Leiomyoma in Reproductive Women

XPC gene belongs to DNA repair pathway, which is involved in the development of uterine leiomyoma. However, its relationships with leiomyoma risk were never reported. We here hypothesized that XPC gene was associated with the risk of uterine leiomyoma. In this case-control study with a total of 391 leiomyoma cases and 493 tumor-free controls in a reproductive women population in South China, two missense polymorphisms rs2228001 A > C (Lys939Gln) and rs2228000 C > T (Ala499Val) were genotyped by quantitative polymerase chain reaction (qPCR). Then, the associations between these two polymorphisms and leiomyoma risk were investigated. It was revealed that the rs2228000 CT/TT variant genotypes had a decreased leiomyoma risk (adjusted odds ratio = 0.73, 95% confidence interval = 0.54-0.94) compared with rs2228000 CC genotype. Further stratified analysis also revealed that the protective effect of rs2228000 CT/TT on the risk of uterine leiomyoma was more evident among subjects who were younger than 35 years old compared with those with larger tumors (diameter of tumor >5 cm), and those with fewer number of myomas (only one). However, no significant association was observed for leiomyoma risk for rs2228001 A > C. This study indicated that genetic variations in XPC gene are associated with leiomyoma susceptibility in a reproductive women population. It warrants further confirmation in larger prospective studies with different populations.

Thyroid Cancer: The Quest for Genetic Susceptibility Involving DNA Repair Genes

The incidence of thyroid cancer (TC), particularly well-differentiated forms (DTC), has been rising and remains the highest among endocrine malignancies. Although ionizing radiation (IR) is well established on DTC aetiology, other environmental and genetic factors may also be involved. DNA repair single nucleotide polymorphisms (SNPs) could be among the former, helping in explaining the high incidence. To further clarify the role of DNA repair SNPs in DTC susceptibility, we analyzed 36 SNPs in 27 DNA repair genes in a population of 106 DTCs and corresponding controls with the aim of interpreting joint data from previously studied isolated SNPs in DNA repair genes. Significant associations with DTC susceptibility were observed for XRCC3 rs861539, XPC rs2228001, CCNH rs2230641, MSH6 rs1042821 and ERCC5 rs2227869 and for a haplotype block on chromosome 5q. From 595 SNP-SNP combinations tested and 114 showing relevance, 15 significant SNP combinations (p < 0.01) were detected on paired SNP analysis, most of which involving CCNH rs2230641 and mismatch repair variants. Overall, a gene-dosage effect between the number of risk genotypes and DTC predisposition was observed. In spite of the volume of data presented, new studies are sought to provide an interpretability of the role of SNPs in DNA repair genes and their combinations in DTC susceptibility.

Effect of XPC polymorphisms on the response to platinum-based chemotherapy: a meta-analysis

Objective: As an important DNA repair gene, the xeroderma pigmentosum complementation group C (XPC) gene and its functional genetic variants' relationship with chemotherapy response has been extensively studied. To quantitatively elucidate the genetic impact of the XPC rs2228000 and rs2228001 polymorphisms on the response to platinum-based chemotherapy, the present meta-analysis was conducted. Materials and methods: A systematic literature search was performed in seven cyber databases until February 20, 2019, for all relevant studies that assessed the relationship between XPC polymorphisms and the response to platinum-based chemotherapy. Odds ratios (ORs) with a 95% confidence interval (95% CI) were measured to assess the strength of the association. R programs were developed to perform the statistical analyses, including calculations of pooled estimates, publication bias and sensitivity analyses, and heterogeneity interpretations. Results: A total of 1,615 patients from 10 studies for the rs2228001 polymorphism were winnowed for further statistical analysis. For the rs2228000 polymorphism, 858 samples from six datasets were included. However, this meta-analysis indicated no significant effect of these two XPC polymorphisms on the response to platinum-based chemotherapy. When stratified according to sample size, country or cancer type, no statistical significance for association was identified in all subgroups. Further sensitivity analysis and publication bias assessment ensured the reliability of the meta-analysis. Conclusions: The pooled estimates suggest that neither the rs2228000 polymorphism nor the rs2228001 polymorphism contributes to the genetic predisposition for an altered response to platinum-based chemotherapy. Considering the limitations of our present meta-analysis, more studies with large-scale cohorts and rigorous methods are needed to validate our results.

Functional Polymorphisms in DNA Repair Genes Are Associated with Sporadic Colorectal Cancer Susceptibility and Clinical Outcome

DNA repair processes are involved in both the onset and treatment efficacy of colorectal cancer (CRC). A change of a single nucleotide causing an amino acid substitution in the corresponding protein may alter the efficiency of DNA repair, thus modifying the CRC susceptibility and clinical outcome. We performed a candidate gene approach in order to analyze the association of non-synonymous single nucleotide polymorphisms (nsSNPs) in the genes covering the main DNA repair pathways with CRC risk and clinical outcome modifications. Our candidate polymorphisms were selected according to the foremost genomic and functional prediction databases. Sixteen nsSNPs in 12 DNA repair genes were evaluated in cohorts from the Czech Republic and Austria. Apart from the tumor-node-metastasis (TNM) stage, which occurred as the main prognostic factor in all of the performed analyses, we observed several significant associations of different nsSNPs with survival and clinical outcomes in both cohorts. However, only some of the genes (REV3L, POLQ, and NEIL3) were prominently defined as prediction factors in the classification and regression tree analysis; therefore, the study suggests their association for patient survival. In summary, we provide observational and bioinformatics evidence that even subtle alterations in specific proteins of the DNA repair pathways may contribute to CRC susceptibility and clinical outcome.

Polymorphisms in XPC gene and risk for prostate cancer

Single nucleotide polymorphisms (SNP) in repair gene DNA such as XPC gene can reduce the DNA repair capacity (DRC). Reduced DRC induce genetic instability and may increase the susceptibility to prostate cancer (PC). We conducted a case-controls study to examine the relationship between XPC Lys939Gln and XPC-PAT polymorphisms and the risk for prostate cancer in Tunisian population. We have also correlated molecular results with clinical parameters (Gleason score and TNM status) and lifestyle factors (tobacco status, alcohol consumption, and exposition to professional risk factors) of prostate cancer patients. We have found that the XPC Lys939Gln polymorphism was not associated with a risk of prostate cancer. However the XPC PAT I/I genotype was found to be associated with 3.83-fold increased risk of prostate cancer compared to controls (p = 0.00006; OR 3.83; 95% CI (1.83-8.05)). The test of linkage disequilibrium showed that XPC-PAT polymorphism is in linkage disequilibrium with XPC Lys939Gln variants. The combined analysis of XPC Lys939Gln and XPC-PAT variants showed that patients who inherited (Lys/Gln + PAT D/D) genotypes were protected against prostate cancer development compared to controls. In the other hand, no significant association has been found between XPC polymorphisms and clinical parameters or between XPC polymorphisms and lifestyle factors.

Pathway-based analysis of genome-wide association study of circadian phenotypes

Sleepiness affects normal social life, which attracts more and more attention. Circadian phenotypes contribute to obvious individual differences in susceptibility to sleepiness. We aimed to identify candidate single nucleotide polymorphisms (SNPs) which may cause circadian phenotypes, elucidate the potential mechanisms, and generate corresponding SNP-gene-pathways. A genome-wide association studies (GWAS) dataset of circadian phenotypes was utilized in the study. Then, the Identify Candidate Causal SNPs and Pathways analysis was employed to the GWAS dataset after quality control filters. Furthermore, genotype-phenotype association analysis was performed with HapMap database. Four SNPs in three different genes were determined to correlate with usual weekday bedtime, totally providing seven hypothetical mechanisms. Eleven SNPs in six genes were identified to correlate with usual weekday sleep duration, which provided six hypothetical pathways. Our results demonstrated that fifteen candidate SNPs in eight genes played vital roles in six hypothetical pathways implicated in usual weekday bedtime and six potential pathways involved in usual weekday sleep duration.

Nucleotide Excision Repair Factor XPC Ameliorates Prognosis by Increasing the Susceptibility of Human Colorectal Cancer to Chemotherapy and Ionizing Radiation

Nucleotide excision repair (NER) is a DNA damage repair mechanism in mammals, but the relationship between NER and human colorectal cancer (HRC) progression has not been clarified yet. In this study, the expression of the NER genes XPA, XPC, XPF, XPG, ERCC1, and XPD was measured in normal and cancerous human colorectal tissue. Among them, only the XPC gene expression was significantly increased in colorectal cancer tissue. To establish the role of XPC in colorectal cancer, small interference RNA (siRNA) targeting XPC was used to knockdown the expression of XPC in HRC cell lines. In addition, an expression vector plasmid containing the XPC cDNA was constructed and stably transfected into HRC cell lines to overexpress the XPC gene. Interestingly, MTT and apoptosis assay demonstrated that XPC gene overexpression significantly increased the susceptibility of HRC cell lines to cisplatin and X-ray radiation. In order to study the relationship between XPC expression and the progression of HRC, XPC expression was measured in 167 patients with colorectal cancer. The results showed that patients with high XPC expression had longer survival time. Cox regression analysis showed that high XPC expression might be a potential predictive factor for colorectal cancer. In conclusion, XPC plays a key role in the susceptibility of colorectal cancer to chemotherapy and ionizing radiation and is associated with a good patients' prognosis.

Nucleotide excision repair pathway gene polymorphisms are linked to breast cancer risk in a Chinese population

Polymorphisms in nucleotide excision repair (NER) pathway genes are associated with the risk of breast cancer, but the relevance of these associations appeared to vary according to the ethnicity of the subjects. To systemically evaluate the potential associations between NER polymorphisms and breast cancer risk in a Chinese population, we carried out a case-control study on 450 breast cancer patients and 430 healthy controls. Sequenom MassARRAY was used for genotyping, and immunohistochemistry was performed to detect estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2) expression in tumor tissue. Our results showed that ERCC1 rs11615 (additive model: OR_adjusted: 1.36, 95% CI: 1.08-1.71, p = 0.009), XPC rs2228000 (additive model: OR_adjusted: 1.39, 95% CI: 1.13-1.72, p = 0.002) and ERCC2/XPD rs50872 (additive model: OR_adjusted: 1.32, 95% CI: 1.04-1.67, p = 0.021) were associated with an increased risk of breast cancer. Stratified analysis revealed three polymorphisms (rs11615, rs1800975, and rs50872) to be associated with breast cancer in menopausal females. Three polymorphisms were associated with specific breast cancer grades (rs11615 with grade 3, rs2228000 and rs50872 with grade 1-2). Two polymorphisms (rs2228001 and rs50872) were associated with the risk of breast cancer with negative lymph node involvement. rs1800975 and rs50872 were associated with the risk of ER⁻ and PR⁻ breast cancer, whereas rs11615 was associated with the risk of ER⁺ and PR⁺ breast cancer. We found that carriers of the T allele of ERCC1 rs11615, XPC rs2228000 and rs50872, particularly in postmenopausal females, have an increased risk of breast cancer.

Genetic variants in the nucleotide excision repair pathway genes and gastric cancer susceptibility in a southern Chinese population

BACKGROUND

Potentially functional polymorphisms can modulate protein activities and host's DNA repair capacity, thereby influencing cancer susceptibility. The association of the polymorphisms in the nucleotide excision repair core pathway genes and gastric cancer susceptibility remains largely unknown.

METHODS

Here, we systematically analyzed the associations between nine polymorphisms in four key genes (XPA, ERCC1, ERCC2, and ERCC4) in the nucleotide excision repair pathway and gastric cancer risk in a Chinese population including 1142 patients and 1173 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the risk associations.

RESULTS

We observed that ERCC1 rs2298881 CA variant genotype was associated with an increased gastric cancer risk (CA vs. CC: adjusted OR [AOR]=1.33, 95% CI=1.09-1.62; dominant model: AOR=1.32, 95% CI=1.10-1.60). However, ERCC1 rs3212986 AA variant genotype was identified as a protective factor for gastric cancer (AA vs. CC: AOR=0.73, 95% CI=0.54-0.98; recessive model: AOR=0.72, 95% CI=0.54-0.96). Genotype-based mRNA expression analysis further indicated that the rs2298881 A allele was associated with decreased ERCC1 mRNA expression.

CONCLUSION

In all, these results indicated that the ERCC1 polymorphisms may affect the risk of gastric cancer in the Chinese Han population.

Genetic Variations of GWAS-Identified Genes and Neuroblastoma Susceptibility: a Replication Study in Southern Chinese Children

Neuroblastoma is one of the most commonly diagnosed solid cancers for children, and genetic factors may play a critical role in neuroblastoma development. Previous genome-wide association studies (GWASs) have identified nine genes associated with neuroblastoma susceptibility in Caucasians. To determine whether genetic variations in these genes are also associated with neuroblastoma susceptibility in Southern Chinese children, we genotyped 25 polymorphisms within these genes by the TaqMan method in 256 cases and 531 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the strength of the associations. We performed a meta-analysis to further evaluate the associations. Furthermore, we calculated the area under the receiver-operating characteristic curves (AUC) to assess which gene/genes may better predict neuroblastoma risk. We confirmed that CASC15 rs6939340 A>G, rs4712653 T>C, rs9295536 C>A, LIN28B rs221634 A>T, and LMO1 rs110419 A>G were associated with significantly altered neuroblastoma susceptibility. We also confirmed that rs6939340 A>G (G versus A: OR=1.30, 95% CI=1.13-1.50) and rs110419 G>A (A versus G: OR=1.37, 95% CI=1.19-1.58) were associated with increased neuroblastoma risk for all subjects. We also found that the combination of polymorphisms in CASC15, LIN28B, and LMO1 may be used to predict neuroblastoma risk (AUC=0.63, 95% CI=0.59-0.67). Overall, we verified five GWAS-identified polymorphisms that were associated with neuroblastoma susceptibility alteration for Southern Chinese population; however, these results need further validation in studies with larger sample sizes.

A 3' untranslated region polymorphism rs2304277 in the DNA repair pathway gene OGG1 is a novel risk modulator for urothelial bladder carcinoma

Altered DNA repair capacity may affect an individual's susceptibility to cancers due to compromised genomic integrity. This study was designed to elucidate the association of selected polymorphisms in DNA repair genes with urothelial bladder carcinoma (UBC). OGG1 rs1052133 and rs2304277, XRCC1 rs1799782 and rs25487, XRCC3 rs861539, XPC rs2228001, and XPD rs13181 were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 200 UBC cases and 200 controls. We found association of OGG1 rs2304277 [odds ratio (OR)_GG = 3.55, 95% confidence interval (CI) = 1.79-7.06] and XPC rs2228001 (OR_AC = 2.38, 95% CI = 1.43-3.94) with UBC. In stratified analysis with respect to smoking status, OGG1 rs2304277 and XPC rs2228001 exhibited increased risk in smokers [(rs2304277 OR_GG = 4.96, 95% CI = 1.51-16.30) (rs2228001 OR_AC = 2.19, 95% CI = 1.02-4.72)] as well as nonsmokers [(rs2304277 OR_GG = 2.95, 95% CI = 1.26-6.90) (rs2228001 OR_AC = 2.57, 95% CI = 1.31-5.04)]. These polymorphisms were also associated with both low-grade [(rs2304277 OR_GG = 3.73, 95% CI = 1.72-8.09) (rs2228001 OR_AC = 2.18, 95% CI = 1.21-3.92)] and high-grade tumors [(rs2304277 OR_GG = 3.45, 95% CI = 1.52-7.80) (rs2228001 OR_AC = 2.81, 95% CI = 1.48-5.33)] as well as with non-muscle-invasive bladder cancer [(rs2304277 OR_GG = 4.03, 95% CI = 1.87-8.67) (rs2228001 OR_AC = 2.14, 95% CI = 1.20-3.81)] and muscle-invasive bladder cancer [(rs2304277 OR_GG = 3.06, 95%CI = 1.31-7.13) (rs2228001 OR_AC = 2.95, 95%CI = 1.51-5.75)]. This is the first study on DNA repair gene polymorphisms and UBC in the Pakistani population. It identifies OGG1 rs2304277 and replicates XPC rs2228001 as significant modulators of UBC susceptibility.

A Polymorphism Located Near PMAIP1/Noxa Gene Influences Susceptibility to Hodgkin Lymphoma Development in South India

Background:

Single nucleotide polymorphisms (SNPs) in DNA repair and Toll-like receptor (TLR) genes have been reported to be associated with Hodgkin Lymphoma (HL) risk. Since such associations may be ethnicity dependent, polymorphisms in TLR4 rs1554973, Xeroderma pigmentosum C (XPC) rs2228000, rs2228001 and a variant near PMAIP1/Noxa gene rs8093763 were here investigated with regard to HL susceptibility in a south Indian population. Normative frequencies of SNPs were established and compared with data for 1000 genome populations.

Methods:

We conducted a case control study consisting of 200 healthy volunteers and 101 cases with HL. DNA samples were genotyped using real-time PCR. Linkage disequilibrium (LD) analysis between rs2228000 and rs2228001 was performed using HaploView (version 4.2).

Results:

Among the studied variants, we observed that a variant rs8093763 located near PMAIP1/Noxa gene was associated with HL risk (OR=1.72 and 95% CI=1.004-2.93). The major allele frequencies of XPC (rs2228000 and rs2228001), TLR4 (rs1554973) and PMAIP1/NOXA (rs8093763) variants were 79%, 66%, 67% and 59% respectively. The studied frequencies were significantly different from 1000 genome populations.

Conclusion:

The results suggest that a variant rs8093763 located near the PMAIP1/Noxa gene may modify risk of HL. We found variation in distribution of polymorphic frequencies between the study population and 1000 genome populations. The results may help identify individual risk of development of HL in our south Indian population.

XPG gene rs751402 C>T polymorphism and cancer risk: Evidence from 22 publications

The Xeroderma pigmentosum group G (XPG) gene promotes recognition and excision of damaged DNA during the DNA repair process. We conducted a comprehensive search of the MEDLINE, EMBASE, and Chinese Biomedical databases for publications evaluating the association XPG gene rs751402 C>T polymorphism and overall cancer risk. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were adopted to assess the strength of the association. A total of 22 publications encompassing 10538 cases and 10511 control subjects were included in the final meta-analysis. We found the polymorphism to be associated with increased cancer risk (TT vs. CC: OR = 1.18, 95% CI = 1.01-1.38, P = 0.040; CT vs. CC: OR = 1.12, 95% CI = 1.01-1.24, P = 0.040; and CT/TT vs. CC: OR = 1.12, 95% CI = 1.002-1.26, P = 0.045). Stratification by cancer type indicated that this polymorphism may increase the risk of gastric cancer and hepatocellular carcinoma, which was further confirmed by a false-positive report probability analysis. Genotype-based mRNA expression provides further evidence that this polymorphism is associated with altered XPG mRNA expression. This meta-analysis suggests XPG gene rs751402 C>T polymorphism correlates with overall cancer risk, especially for gastric cancer and hepatocellular carcinoma.

Exposure to meat-derived carcinogens and bulky DNA adduct levels in normal-appearing colon mucosa

INTRODUCTION

Meat consumption is a risk factor for colorectal cancer. This research investigated the relationship between meat-derived carcinogen exposure and bulky DNA adduct levels, a biomarker of DNA damage, in colon mucosa.

METHODS

Least squares regression was used to examine the relationship between meat-derived carcinogen exposure (PhIP and meat mutagenicity) and bulky DNA adduct levels in normal-appearing colon tissue measured using ³²P-postlabelling among 202 patients undergoing a screening colonoscopy. Gene-diet interactions between carcinogen exposure and genetic factors relevant to biotransformation and DNA repair were also examined. Genotyping was conducting using the MassARRAY^® iPLEX^® Gold SNP Genotyping assay.

RESULTS

PhIP and higher meat mutagenicity exposures were not associated with levels of bulky DNA adducts in colon mucosa. The XPC polymorphism (rs2228001) was found to associate with bulky DNA adduct levels, whereby genotypes conferring lower DNA repair activity were associated with higher DNA adduct levels than the normal activity genotype. Among individuals with genotypes associated with lower DNA repair (XPD, rs13181 and rs1799179) or detoxification activity (GSTP1, rs1695), higher PhIP or meat mutagenicity exposures were associated with higher DNA adduct levels. Significant interactions between the XPC polymorphism (rs2228000) and both dietary PhIP and meat mutagenicity on DNA adduct levels was observed, but associations were inconsistent with the a priori hypothesized direction of effect.

CONCLUSION

Exposure to meat-derived carcinogens may be associated with increased DNA damage occurring directly in the colon among genetically susceptible individuals.

Polymorphisms of protamine genes contribute to male infertility susceptibility in the Chinese Han population

Protamine (PRM) plays important roles in the packaging of DNA within the sperm nucleus. To investigate the role of PRM1/2 and transition protein 1 (TNP1) polymorphisms in male infertility, 636 infertile men and 442 healthy individuals were recruited into this case-controlled study of the Chinese Han population, using MassARRAY technology to analyze genotypes. Our analysis showed that there were no significant differences between controls and infertile cases among the five single nucleotide polymorphisms identified in PRM1, PRM2 and TNP1 [rs737008 (G/A), rs2301365 (C/A), rs2070923 (C/A), rs1646022 (C/G) and rs62180545 (A/G)]. However, we found that the PRM1 and PRM2 haplotypes GCTGC, TCGCA and TCGCC exhibited significant protective effects against male infertility compared to fertile men, while TCGGA, GCTCC and TCGGC represented significant risk factors for spermatogenesis. Our data showed that rs737008 and rs2301365 in PRM1, and rs1646022 in PRM2, were significantly associated with male infertility and that gene–gene interaction played a role in male infertility. A linkage disequilibrium plot for the five SNPs showed that rs737008 was strongly linked with both rs2301365 and rs2070923. These findings are likely to help improve our understanding of the etiology of male infertility. Further studies should include a larger number of genes and SNPs, particularly growing critical genes; such studies will help us to unravel the effect of individual genetic factors upon male infertility.

CASP8 -652 6N insertion/deletion polymorphism and overall cancer risk: evidence from 49 studies

The CASP8 -652 6N insertion/deletion (I/D) polymorphism reduces expression of caspase 8. We conducted a meta-analysis to clarify the relationship between this polymorphism and cancer risk. Eligible articles were retrieved from PubMed, EMBASE, CNKI, and WANFANG databases through February 2017. A total of 33 articles with 49 studies, including 33,494 cases and 36,397 controls, were analyzed. We found that the CASP8 -652 6N ins/del polymorphism was associated with decreased overall cancer risk in five genetic models [DD vs. II: odds ratio (OR)=0.76, 95% confidence interval (CI)=0.69–0.84, ID vs. II: OR=0.87, 95% CI=0.83–0.92, DD vs. ID/II: OR=0.82, 95% CI=0.75–0.89, ID/DD vs. II: OR=0.85, 95% CI=0.80–0.90, and D vs. I: OR=0.87, 95% CI=0.83–0.91]. Stratified analyses showed that the polymorphism was associated with decreased risk of colorectal, breast, esophageal, renal cell, lung, cervical, bladder, gastric, and other cancers. Overall cancer risk was reduced in Asian and Caucasian patients, both hospital- and population-based studies, and both high and low quality studies. Our results highlight the role of the CASP8 -652 6N ins/del polymorphism in decreasing cancer risk. Further studies with large-cohort populations, especially for specific cancer types and ethnic groups, are needed to confirm our findings.

Polymorphisms in nucleotide excision repair genes and risk of primary prostate cancer in Chinese Han populations

Genetic variants of nucleotide excision repair (NER) genes have been extensively investigated for their roles in the development of prostate cancer (PCa); however, the published results have been inconsistent. In a hospital-based case-control study of 1,004 PCa cases and 1,055 cancer-free controls, we genotyped eight potentially functional single nucleotide polymorphisms (SNPs) of NER genes (i.e., XPC, rs2228001 T>G and rs1870134 G>C; XPD, rs13181 T>G and rs238406 G>T; XPG, rs1047768 T>C, rs751402 C>T, and rs17655 G>C; and XPF, rs2276464 G>C) and assessed their associations with risk of PCa by using logistic regression analysis. Among these eight SNPs investigated, only XPC rs1870134 CG/CC variant genotypes were associated with a decreased risk of prostate cancer under a dominant genetic model (adjusted odds ratio [OR] = 0.77, 95% confidence interval [CI] = 0.64-1.91, P = 0.003). Phenotype-genotype analysis also suggested that the XPC rs1870134 CG/CC variant genotypes were associated with significantly decreased expression levels of XPC mRNA in a mix population of different ethnicities. These findings suggested that XPC SNPs may contribute to risk of PCa in Eastern Chinese men.

NFKB1 -94insertion/deletion ATTG polymorphism and cancer risk: Evidence from 50 case-control studies

Nuclear factor-kappa B1 (NF-κB1) is a pleiotropic transcription factor and key contributor to tumorigenesis in many types of cancer. Numerous studies have addressed the association of a functional insertion (I)/deletion (D) polymorphism (-94ins/delATTG, rs28362491) in the promoter region of NFKB1 gene with the risk of various types of cancer; however, their conclusions have been inconsistent. We therefore conducted a meta-analysis to reevaluate this association. PubMed, EMBASE, China National Knowledge infrastructure (CNKI), and WANFANG databases were searched through July 2016 to retrieve relevant studies. After careful assessment, 50 case-control studies, comprising 18,299 cases and 23,484 controls were selected. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were used to determine the strength of the association. The NFKB1 -94ins/delATTG polymorphism was associated with a decreased risk of overall cancer in the homozygote model (DD vs. II): OR = 0.75, 95% CI = 0.64-0.87); heterozygote model (ID vs. II): OR = 0.91, 95% CI = 0.83-0.99; recessive model (DD vs. ID/II): OR = 0.81, 95% CI = 0.71-0.91; dominant model (ID/DD vs. II): OR = 0.86, 95% CI = 0.78-0.95; and allele contrast model (D vs. I): OR = 0.88, 95% CI = 0.81-0.95). Subgroup and stratified analyses revealed decreased risks for lung cancer, nasopharyngeal carcinoma, prostate cancer, ovarian cancer, and oral squamous cell carcinoma, and this association held true also for Asians (especially Chinese subjects) in hospital-based studies, and in studies with quality scores less than nine. Well-designed, large-scale case-control studies are needed to confirm these results.

Nucleotide Excision Repair Capacity and XPC and XPD Gene Polymorphism Modulate Colorectal Cancer Risk

BACKGROUND

Colorectal cancer (CRC) is leading malignant tumors to occur mainly in industrialized countries, where it exhibits one of the highest mortality rates. Up to 80% of all CRCs characterize a chromosomal instability (CIN) phenotype. The main challenge faced by scientist is to reveal the mechanism of CIN development. An often proposed model is defects in DNA repair in terms of efficiency and genetic variations that modulate the response to stimuli from the environment. The objectives of this research were to determine whether nucleotide excision repair (NER) might affect CRC risk.

MATERIALS AND METHODS

The first part of the study concerns NER efficiency. In the second part we selected 2 common single nucleotide polymorphisms within genes involved in NER (Xeroderma pigmentosum group C (XPC) Lys939Gln, Xeroderma pigmentosum group D (XPD) Lys751Gln) to determine the relation between them and CRC risk. The restriction fragment length polymorphism-polymerase chain reaction method was used for genotyping of 221 CRC patients vs. 270 cancer-free individuals. The isotopic labeling in vitro assay was used to evaluate NER capacity in lymphocytes and tissue protein extracts.

RESULTS

We observed a significantly decreased level of NER capacity (P = .025) in lymphocytes delivered from CRC patients compared with healthy ones. Polymorphism screening points to higher CRC risk for the Gln939Gln genotype (P = .02) and Gln allele (P = .002) of the XPC gene.

CONCLUSION

Taken together, our findings suggest a potential role for NER in CRC.

MDM2 promoter del1518 polymorphism and cancer risk: evidence from 22,931 subjects

Studies have shown that single-nucleotide polymorphisms in MDM2 gene may play important roles in the development of malignant tumor. The association of del1518 polymorphism (rs3730485) in the MDM2 promoter with cancer susceptibility has been extensively studied; however, the results are contradictory. To quantify the association between this polymorphism and overall cancer risk, we conducted a meta-analysis with 12,905 cases and 10,026 controls from 16 eligible studies retrieved from PubMed, Embase, and Chinese Biomedical (CBM) databases. We assessed the strength of the connection using odds ratios (ORs) and 95% confidence intervals (CIs). In summary, no significant associations were discovered between the del1518 polymorphism and overall cancer risk (Del/Del vs Ins/Ins: OR =1.01, 95% CI =0.90-1.14; Ins/Del vs Ins/Ins: OR =1.03, 95% CI =0.96-1.12; recessive model: OR =0.98, 95% CI =0.90-1.07; dominant model: OR =1.03, 95% CI =0.94-1.12; and Del vs Ins: OR =1.01, 95% CI =0.94-1.07). In the stratified analysis by source of control, quality score, cancer type, and ethnicity, no significant associations were found. Despite some limitations, the current meta-analysis provides solid statistical evidence of lacking association between the MDM2 del1518 polymorphism and cancer risk.

Increased micronucleus frequency in peripheral blood lymphocytes predicts the risk of bladder cancer

Background:

Bladder cancer (BC) is among the most common malignancies worldwide. The identification of new biomarkers for early BC detection, recurrence/progression is urgently needed. The cytokinesis-block micronucleus assay (CBMN) evaluates chromosome damage in cultured human lymphocytes and micronuclei (MN) provide a convenient and reliable index of both chromosome breakage and loss.

Methods:

Chromosomal damage (expressed as frequencies of MN, nucleoplasmic bridges and nuclear buds (NBUD)) was evaluated by CBMN assay in cryopreserved lymphocytes from 158 age/smoking-matched pairs of cases and controls in relation to BC risk, recurrence or progression. Moreover, non-muscle invasive BC (NMIBC) patients were characterised for 783 DNA repair gene polymorphisms for their possible association with the investigated cytogenetic end points.

Results:

MN and NBUD frequencies were significantly higher in cases than in controls (P=0.001 and P=0.006, respectively), with the associations being stronger in NMIBC. In a logistic regression model, for each increase of one unit in the MN frequency, a 1.12 increased risk of developing NMIBC was observed. In NMIBC cases, 10 polymorphisms were associated with different MN frequencies after genotype stratification.

Conclusions:

A model including traditional BC risk factors, MN frequency and the selected polymorphisms differentially distributed in cases and controls improved BC patient identification. Understanding the meaning of systemic chromosomal damage in BC patients with respect to the general population may help to adopt specific prevention strategies and therapeutic intervention.

MDM4 rs4245739 A > C polymorphism correlates with reduced overall cancer risk in a meta-analysis of 69477 subjects

Mouse double minute 4 (MDM4) is a p53-interacting oncoprotein that plays an important role in the p53 tumor suppressor pathway. The common rs4245739 A > C polymorphism creates a miR-191 binding site in the MDM4 gene transcript. Numerous studies have investigated the association between this MDM4 polymorphism and cancer risk, but have failed to reach a definitive conclusion. To address this issue, we conducted a meta-analysis by selecting eligible studies from MEDLINE, EMBASE, and Chinese Biomedical databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. We also performed genotype-based mRNA expression analysis using data from 270 individuals retrieved from public datasets. A total of 15 studies with 19796 cases and 49681 controls were included in the final meta-analysis. The pooled results revealed that the MDM4 rs4245739C allele is associated with a decreased cancer risk in the heterozygous (AC vs. AA: OR = 0.82, 95% CI = 0.73-0.93), dominant (AC/CC vs. AA: OR = 0.82, 95% CI = 0.72-0.93), and allele contrast models (C vs. A: OR = 0.84, 95% CI = 0.76-0.94). The association was more prominent in Asians and population-based studies. We also found that the rs4245739C allele was associated with decreased MDM4 mRNA expression, especially for Caucasians. Thus the MDM4 rs4245739 A > C polymorphism appears to be associated with decreased cancer risk. These findings would be strengthened by new studies with larger sample sizes and encompassing additional ethnicities.

Association of XPC Gene Polymorphisms with Colorectal Cancer Risk in a Southern Chinese Population: A Case-Control Study and Meta-Analysis

Xeroderma pigmentosum group C (XPC) is a key component of the nucleotide excision repair (NER) pathway. Dysfunctional XPC protein may impair NER-mediated DNA repair capacity and further lead to genomic instability and carcinogenesis. Two common nonsynonymous polymorphisms in the XPC gene, Lys939Gln (rs2228001 A > C) and Ala499Val (rs2228000 C > T), have been investigated in various types of cancer. We genotyped these two polymorphisms in 1141 cases with histologically confirmed colorectal cancer (CRC) and 1173 healthy controls to explore their causative association with CRC susceptibility. Overall, no association was observed between these two variants and the risk of CRC. Our meta-analysis also confirmed a lack of overall association. Stratified analyses were performed by age, gender, smoking status, pack-year, drinking status, tumor sites, and Duke's stages. We found that XPC Lys939Gln polymorphism was significantly associated with an increased CRC risk in subjects at 57 years of age or younger (adjusted odds ratio (OR) = 1.37, 95% confidence interval (CI) = 1.004-1.86, p = 0.047) and non-drinkers (adjusted OR = 1.53, 95% CI = 1.10-2.12, p = 0.011). Our results indicated that XPC Lys939Gln may be a low-penetrance CRC susceptibility polymorphism. Our findings warrant further validation.

Association between XRCC3 Thr241Met polymorphism and nasopharyngeal carcinoma risk: evidence from a large-scale case-control study and a meta-analysis

The X-ray repair cross-complementing group 3 (XRCC3) Thr241Met polymorphism (rs861539, C > T) has drawn wide attentions as its association with cancer risk and its involvement in DNA repair. Several studies have attempted to link rs861539 to nasopharyngeal cancer (NPC) risk; however, the sample sizes of these studies are small and the results are controversial. To investigate the relationship of rs861539 and NPC susceptibility, we conducted a large-scale case-control study involving 4001 NPC cases and 2967 controls of southern Chinese. Logistic regression analysis revealed significant association for rs861539 and NPC risk under the recessive model (TT vs. CT + CC) with adjustment of age and gender (odds ratio, OR = 2.72; 95 % CI 1.10-6.72; P = 0.03). Further, meta-analysis involving 4457 NPC cases and 4132 controls from four studies showed consistent association of TT carriers and NPC risk (OR = 3.12; 95 % CI 1.58-6.13; P = 0.001). Taken together, our findings based on large-scale sample size suggested rs861539 at XRCC3 to be associated with NPC risk through recessive model.

XPG Gene Polymorphisms Contribute to Colorectal Cancer Susceptibility: A Two-Stage Case-Control Study

Previous studies have reported that xeroderma pigmentosum group G (XPG) gene polymorphisms may modulate colorectal cancer (CRC) susceptibility. In this study, we performed a two-stage case-control study to comprehensively investigate the associations of five polymorphisms in the XPG gene with CRC risk in 1,901 cases and 1,976 controls from Southern China, including rs2094258 C>T, rs751402 C>T, rs2296147 T>C, rs1047768 T>C and rs873601 G>A. After combining data from two stages, we found that three of the studied polymorphisms (rs2094258 C>T, rs751402 C>T, and rs873601 G>A) were significantly associated with CRC susceptibility. After adjustment for age and gender, multivariate logistic regression analysis indicated that carriers of the rs2094258 T alleles had an increased CRC risk [CT vs. CC: adjusted odds ratio (OR)=1.17, 95% confidence interval (CI)=1.01-1.36; TT vs. CC: adjusted OR=1.49, 95% CI=1.18-1.89; TT vs. CT/CC: adjusted OR=1.38, 95% CI=1.10-1.72]. Likely, rs873601 A allele also conferred increased CRC susceptibility. In contrast, a protective association was identified between rs751402 C>T polymorphism and the risk of CRC. In summary, our results indicated that these three polymorphisms were found to associate with CRC susceptibility in a Southern Chinese population.

Potentially functional polymorphisms in the LIN28B gene contribute to neuroblastoma susceptibility in Chinese children

Neuroblastoma is the most commonly diagnosed solid tumour outside the central nervous system in children. However, genetic factors underlying neuroblastoma remain largely unclear. Previous genome-wide association study indicated that lin-28 homolog B (LIN28B) might play an important role in the development of neuroblastoma and also contributed to its poor overall survival. With the purpose to evaluate the association between LIN28B gene polymorphisms and neuroblastoma susceptibility in Southern Chinese population, we conducted this study with 256 neuroblastoma cases and 531 cancer-free controls. Four potentially functional polymorphisms (rs221634 A>T, rs221635 T>C, rs314276 C>A and rs9404590 T>G) were genotyped using Taqman method. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the associations between the selected single nucleotide polymorphisms (SNPs) and neuroblastoma susceptibility. We also performed genotype-phenotype association analysis to explore the effects of the selected SNPs on LIN28B gene transcripts. Our results indicated that the rs221634 TT genotype was associated with an increased neuroblastoma risk (TT versus

AA/AT

adjusted OR = 1.50, 95% CI = 1.04-2.17). The association was more pronounced in males, patients with tumour of mediastinum origin, as well as patients in early clinical stages. Moreover, overall analysis and stratified analysis also showed an increased risk of neuroblastoma for carrier of the 2-4 risk genotypes. In summary, these results indicated that the LIN28B rs221634 A>T polymorphism was associated with an increased neuroblastoma risk in Southern Chinese children. These findings need further validation in large studies with different ethnicities involved.

Polymorphisms in DNA repair genes in gastrointestinal stromal tumours: susceptibility and correlation with tumour characteristics and clinical outcome

DNA repair pathways play an essential role in cancer susceptibility by maintaining genomic integrity. This led us to investigate the influence of polymorphisms in the genes coding repair pathway enzymes on gastrointestinal stromal tumours (GIST) susceptibility, tumour characteristics and clinical outcome. We investigated a panel of 20 polymorphisms in 11 genes in 81 cases and 147 controls. The XPD rs13181 wild-type allele and hOGG1 rs1052133 and XPF rs1800067 minor alleles were significantly associated with disease susceptibility. XPA rs1800975 and rs2808668 were associated with tumour size (P = 0.018), metastatic status at onset (P = 0.035) and mitotic index (P = 0.002). With regards to outcome treatment, the XPD rs50872 minor allele had a significant favourable impact on time to progression (TTP). Similarly, the XPC rs2228000 minor allele was correlated with a longer TTP (P = 0.03). On the contrary, the XPC rs2228001 and hOGG1 rs1052133 minor alleles were associated with a diminished TTP (P = 0.005 and P = 0.01, respectively). Regarding OS, we found the presence of at least one hOGG1 (rs1052133) minor allele that had a 60 % lower risk to die compared to the wild-type carriers (P = 0.04). Furthermore, the XRCC3 rs861539 variant allele is associated with a hazard of early death compared with the wild-type genotype (P = 0.04). To the best of our knowledge, this is the first study on polymorphisms in DNA repair genes, belonging to the different pathways, extensively evaluated in GIST patients. Through this multiple candidate gene approach, we report for the first time the significant associations between polymorphisms in DNA repair genes, susceptibility, clinical pathological features and clinical outcome in GIST.

Polymorphisms in the XPC gene affect urinary bladder cancer risk: a case-control study, meta-analyses and trial sequential analyses

Compromised activity of the DNA repair enzymes may raise the risk of a number of cancers. We analyzed polymorphisms in the Xeroderma Pigmentosum, Complementation Group C (XPC) gene for their correlation with urinary bladder cancer. Ala499Val and Lys939Gln polymorphisms were genotyped in 234 urinary bladder cancer cases and 258 control samples. A significant association between Ala499Val polymorphism and bladder cancer was observed (OR = 1.78, CI = 1.19–2.66, p = 0.005); however, Lys939Gln was unrelated (OR = 0.97, CI = 0.65–1.45, P = 0.89). Further analysis revealed that Ala499Val was a significant risk factor only in the presence of smoking (OR = 2.23, CI = 1.28–3.87, p < 0.004) or tobacco chewing (OR = 2.40, CI = 1.43–4.04, p = 0.0008). To further appraise the association, we undertook meta-analyses on seven studies (2893 cases and 3056 controls) on Ala499Val polymorphism and eleven studies (5064 cases and 5208 controls) on Lys939Gln polymorphism. Meta-analyses corroborated the above results, showing strong association of Ala499Val (OR = 1.54, CI = 1.21–1.97, p = 0.001) but not that of Lys939Gln (OR = 1.13, CI = 0.95–1.34, p = 0.171) with urinary bladder cancer risk. In conclusion, XPC Ala499Val substitution increases urinary bladder cancer risk, but Lys939Gln appears to be neutral.

Air pollution and childhood bronchitis: Interaction with xenobiotic, immune regulatory and DNA repair genes

BACKGROUND

Gene-environment interactions have been investigated for diseases such as asthma, chronic obstructive pulmonary disease, cancer etc. but acute disease like bronchitis has rarely been studied. We investigated interactions between air pollution (polycyclic aromatic hydrocarbons (PAH) and particulate matter <2.5 μm (PM2.5)) and single nucleotide polymorphisms (SNP) in EPHX1, IL10, STAT4 and XPC genes in relation to bronchitis in children aged 0-2 years.

METHODS

A stratified random sample of 1133 Czech children, born between 1994 and 1998 in two districts, were followed since birth, of which 626 were genotyped. Pediatrician-diagnosed bronchitis episodes were obtained from the medical records. Central-site monitors measured air pollution exposure. We used multivariable logistic regression and estimated coefficients using generalized estimating equations. Interaction was assessed between pollutants and genes and associations in genotype-specific strata were presented. False discovery rate was used to adjust for multiple comparisons.

RESULTS

There were 803 episodes of bronchitis with an incidence rate of 56 per 1000 child-months. We found significant gene-environment interaction between PAH and four SNPs (EPHX1, (rs2854461), STAT4 (rs16833215), XPC (rs2228001 and rs2733532)), which became non-significant after adjusting for multiple comparisons. PM2.5 interactions with two XPC SNPs (rs2228001 and rs2733532) remained significant after accounting for multiple comparisons and those with CC alleles had a more than doubling of odds, OR=2.65 (95% CI: 1.91, 3.69) and 2.72 (95% CI: 1.95, 3.78), respectively, per 25 μg/m(3) increase in exposure.

CONCLUSION

The findings suggest that the DNA repair gene XPC may play an important role in the air pollution-induced pathogenesis of the inflammatory disease bronchitis.

Association Between 3 IL-10 Gene Polymorphisms and Cardiovascular Disease Risk: Systematic Review With Meta-Analysis and Trial Sequential Analysis

Previous studies have yielded controversial results related to the contribution of interleukin 10 (IL-10) gene polymorphisms (IL-10 -592C/A, IL-10 -1082G/A, and IL-10 -819C/T) in the progression of cardiovascular disease (CVD). Thus, we performed a meta-analysis to summarize this situation.Eligible studies were retrieved by searching PubMed, Embase, Web of Science, and Cochrane Library with the last search up to July 7, 2015. Data were pooled by odds ratios (ORs) and their 95% confidence intervals (CIs). False-positive report probability (FPRP) analysis was conducted for all significant findings. Genotype-based mRNA expression analysis was also performed using data from 270 individuals with different ethnicities.Finally, 19 studies for IL-10 -592C/A polymorphism (7284 cases and 7469 controls), 21 studies for IL-10 -1082G/A polymorphism (8263 cases and 5765 controls), and 12 studies for IL-10 -819C/T polymorphism (4502 cases and 3190 controls) were included in the meta-analyses. With respect to IL-10 -819C/T polymorphism, statistically significant decreased CVD risk was found when all studies were pooled into the meta-analysis (T vs C: OR = 0.91, 95% CI = 0.84-0.98; TT + TC vs CC: OR = 0.90, 95% CI = 0.81-1.00). Subgroup analyses stratified by disease subtype suggested the -819C/T polymorphism was significantly associated with a decreased CAD risk (T vs C: OR = 0.90, 95% CI = 0.83-0.97; TT vs CC: OR = 0.81, 95% CI = 0.66-1.00; TT vs TC + CC: OR = 0.82, 95% CI = 0.69-0.98; TT + TC vs CC: OR = 0.89, 95% CI = 0.80-0.99), which was noteworthy finding as evaluated by FPRP. However, with regard to IL-10 -592C/A and IL-10 -1082G/A polymorphisms, no significant association with CVD risk was observed in the overall and subgroup analyses.In conventional meta-analyses, the results suggested that IL-10 -819C/T polymorphism was associated with decreased risk of CVD, especially CAD outcome, whereas IL-10 -592C/A and IL-10 -1082G/A polymorphisms might have no influence on the susceptibility of CVD. However, trial sequential analysis does not allow us to draw any solid conclusion for the association between IL-10 -592C/A or IL-10 -1082G/A polymorphism and CVD risk. Further large and well-designed studies are still needed.

Potential risk of esophageal squamous cell carcinoma due to nucleotide excision repair XPA and XPC gene variants and their interaction among themselves and with environmental factors

The association of nucleotide excision repair (NER) gene polymorphisms with esophageal squamous cell carcinoma (ESCC) is inconclusive. The aim of the current study was to assess the association of repair gene xeroderma pigmentosum A (XPA) (rs-1800975) and xeroderma pigmentosum C (XPC) (rs-2228000) polymorphisms with ESCC risk as well as modifying effects of environmental factors. The genotyping was done in 450 confirmed ESCC cases and equal number of individually matched controls by the polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) and direct sequencing methods. Conditional logistic regression models were used to assess the genotypic associations and interactions. A high ESCC risk was found in subjects who carried the homozygous minor allele of XPA (odds ratio (OR) = 3.57; 95 % confidence interval (CI) = 1.76-7.23), and the risk was higher when analysis was limited to participants who were ever smokers (OR = 4.22; 95 % CI = 2.01-8.88), lived in adobe houses (OR = 8.42; 95 % CI = 3.74-18.95), consumed large volumes of salt tea (OR = 7.42; 95 % CI = 3.30-16.69), or had a positive family history of cancer (FHC) (OR = 9.47; 95 % CI = 4.67-19.20). In case of XPC, a homozygous minor allele also showed strong association with ESCC risk (OR = 4.43; 95 % CI = 2.41-8.16). We again observed a very strong effect of the above environmental factors in elevating the risk of ESCC. Further, the variant genotypes of both genes in combination showed an increased risk towards ESCC (OR = 7.01; 95 % CI = 3.14-15.64) and such association was synergistically significant. Salt tea consumption showed an interaction with genotypes of XPA and XPC. However, an interaction with FHC was significant in the case of XPA genotype only. XPA and XPC genotypes are associated with an increased risk of ESCC, and such association was reasonably modulated by different exposures.

Polymorphisms in the XPC gene and gastric cancer susceptibility in a Southern Chinese population

Previous studies have reported that XPC gene polymorphisms may modify the individual susceptibility to gastric cancer. In this case-control study with a total of 1,142 cases and 1,173 controls, four potentially functional polymorphisms were genotyped in the XPC gene (rs2228001 A>C, rs2228000 C>T, rs2607775 C>G, and rs1870134 G>C) by Taqman assays and their associations were analyzed with the risk of gastric cancer in a Southern Chinese population. No significant association between any of XPC polymorphisms and gastric cancer risk was detected except for a borderline association with the rs2228000 CT/TT genotype (crude odds ratio =0.86, 95% confidence interval =0.73-1.02, P=0.088) when compared to the rs2228000 CC genotype. Further stratified analysis revealed that the protective effect of rs2228000 CT/TT on the risk of gastric cancer was only significant among subjects older than 58 years. In summary, results indicated that genetic variations in XPC gene may play a weak effect on gastric cancer susceptibility in Southern Chinese population, which warrants further confirmation in larger prospective studies with different ethnic populations.

Lack of Associations between XPC Gene Polymorphisms and Neuroblastoma Susceptibility in a Chinese Population

Neuroblastoma is one of the most malignant solid tumors in infants and young children. No more than 40% of neuroblastoma patients can survive for longer than five years after it has been diagnosed. XPC protein is a pivotal factor that recognizes DNA damage and starts up the nucleotide excision repair (NER) in mammalian cells. This makes up the first group to defend against the cancer. Previous studies have identified that XPC gene polymorphisms were associated with various types of cancer. However, the associations between XPC gene polymorphisms and neuroblastoma risk have not yet been studied. We investigated the associations between three XPC gene polymorphisms (rs2228001 A>C, rs2228000 C>T, and rs2229090 G>C) and neuroblastoma risk with 256 neuroblastoma patients and 531 healthy controls in a Chinese Han population. Odds ratios and 95% confidence intervals were used to access the association between these three polymorphisms and neuroblastoma risk. No significant association was detected between these three polymorphisms and neuroblastoma risk in the overall analysis as well as in the stratification analysis. These results suggest that none of these three polymorphisms may be associated with the risk of neuroblastoma in the Chinese Han population.

Association of Interleukin-10 -3575T>A and -1082A>G polymorphisms with non-Hodgkin lymphoma susceptibility: a comprehensive review and meta-analysis

A number of studies have investigated the associations between IL-10 polymorphisms and non-Hodgkin lymphoma (NHL) susceptibility; however, the conclusions were still contradictory. To acquire a more precise estimation of the association, we performed the current meta-analysis. We systematically searched publications from EMBASE and MEDLINE, and calculated pooled odds ratios (ORs) and 95 % confidence intervals (CIs) using either fixed-effects or random-effects model. Genotype-based IL-10 mRNA expression analysis was performed using online public database of 270 individuals with three different ethnicities. A total of 10,703 cases and 11,823 controls from 10 studies were included for the -3575T>A polymorphism, 10,226 cases and 12,215 controls from 17 studies for the -1082A>G polymorphism. Pooled results indicated that IL-10 -3575T>A was associated with increased risk of diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL), especially for Caucasians and hospital-based population. There was no association between IL-10 -1082A>G and NHL risk. However, subgroup analysis showed that IL-10 -1082GG might confer increased susceptibility to FL. In summary, this meta-analysis indicated that -3575T>A polymorphism was associated with altered NHL susceptibility for Caucasians and hospital-based population, especially for DLBCL and FL subtypes. The -1082A>G polymorphism may contribute to increased FL risk. Further large-scale population studies among different ethnicities are needed to validate these results.

The nitric oxide synthase 3 G894T polymorphism associated with Alzheimer's disease risk: a meta-analysis

The association between the G894T polymorphism (Glu298Asp) of nitric oxide synthase 3 (NOS3) and risk of Alzheimer’s disease (AD) was explored by performing a meta-analysis of case-control studies. Bibliographical searches were conducted in the MEDLINE, EMBASE, and China National Knowledge Infrastructure (CNKI) databases without any language limitations. Two investigators independently assessed abstracts for relevant studies, and reviewed all eligible studies. We adopted regrouping in accordance with the most probably appropriate genetic model. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of this association. We performed a meta-analysis including 21 published articles with 23 case-control studies (5,670 cases and 5,046 controls). In the analyses, we found significant association between G894T polymorphism and AD risk under a complete overdominant model (GG + TT vs. GT) (OR = 1.18; 95%CI, 1.04–1.35; P = 0.010). When stratified by time of AD onset, we found the association between this polymorphism and AD susceptibility to be more substantial among late onset patients than among early onset patients (OR for late vs. early onset: 1.33 vs. 1.02, P interaction = 0.049). The meta-analysis showed that the polymorphism G894T of NOS3 was associated with risk of AD.

PSCA s2294008 C>T and rs2976392 G>A polymorphisms contribute to cancer susceptibility: evidence from published studies

PSCA gene plays an important role in cell adhesion, proliferation and survival. Increasing studies have focused on the association of PSCA gene rs2294008 C>T and rs2976392 G>A with cancer risk. However, the conclusions were inconsistent. Therefore, we performed a meta-analysis to elucidate whether there is a true association, or artifact. We systematically searched eligible studies from MEDLINE, EMBASE and CBM database. Odds ratios and 95% confidence intervals were used to evaluate the strength of the association. The final analysis included 32 studies consisting of 30028 cases and 38765 controls for the rs2294008 C>T polymorphism, and 14 studies with 8190 cases and 7176 controls for the rs2976392 G>A polymorphism. Consequently, the PSCA rs2294008 C>T polymorphism was significantly associated with increased overall cancer risk. Further stratifications indicated the increased risk was more pronounced for gastric (diffused type and non-gastric cardia adenocarcinoma) and bladder cancer. A similar association was observed for the rs2976392 G>A polymorphism. This meta-analysis demonstrated that both of the PSCA rs2294008 C>T and rs2976392 G>A polymorphisms are associated with increased cancer risk, especially for gastric cancer and bladder cancer. Further large-scale studies with different ethnicities and subtypes of gastric cancer are required to confirm the results from this meta-analysis.