Laryngeal cancer risk and common single nucleotide polymorphisms in nucleotide excision repair pathway genes ERCC1, ERCC2, ERCC3, ERCC4, ERCC5 and XPA

Relationship between ERCC1 and XPC polymorphisms and the susceptibility to head and neck carcinoma: A systematic review, meta-analysis, and trial sequential analysis

OBJECTIVE

This meta-analysis was conducted to investigate the relationship between ERCC1 and XPC polymorphisms and the risk of head and neck cancer (HNC), incorporating more studies and additional analyses.

DESIGN

An exhaustive search of various databases, including PubMed/Medline, Web of Science, Scopus, and Cochrane Library was carried out, up until November 18, 2023, to identify pertinent studies. The Review Manager 5.3 software was employed to calculate the effect sizes, which were presented as the odds ratio (OR) along with a 95% confidence interval (CI).

RESULTS

The study found that the T allele (OR = 1.11; p-value = 0.02; 95%CI: 1.02, 1.22) and the TT genotype rs2228000 polymorphism in both the homozygous model (OR = 1.61, p-value = 0.02; 95%CI: 1.07, 2.42) and the recessive model (OR = 1.53; p-value = 0.02; 95%CI: 1.06, 2.22) had statistically significant associations. However, no significant associations were found for rs11615, rs3212986, rs735482, rs2228001, and PAT polymorphisms in any genetic models.

CONCLUSIONS

The meta-analysis revealed significant associations for the T allele and TT genotype rs2228000 polymorphism, but not for rs11615, rs3212986, rs735482, rs2228001, and PAT polymorphisms. The results highlight the impact of factors such as ethnicity, cancer subtype, and control source on these associations, emphasizing the intricate nature of genetic interactions in disease risk.

Polymorphisms in ERCC4 and ERCC5 and risk of cancers: Systematic research synopsis, meta-analysis, and epidemiological evidence

The variants of DNA repair genes have been widely reported to be associated with cancer risk in the past decades. As were two crucial members of nucleotide excision repair pathway, ERCC4 and ERCC5 polymorphisms are linked with susceptibility to multiple cancers, but the conclusions were controversial. In this updated meta-analysis concerned with ERCC4 and ERCC5 single-nucleotide polymorphisms (SNPs), 160 eligible publications were identified, and we exerted the meta-analysis of correlations between 24 variants and 19 types of cancer. Venice criteria and the false-positive report probability were used to evaluate a cumulative evidence of significant associations. We conducted functional annotations for those strong associations using data from the Encyclopedia of DNA Elements (ENCODE) Project. We obtained 11 polymorphisms significantly related to changed susceptibility to 11 cancers (p < 0.05). Strong evidence was assigned to four variant-related cancer risks in Asians (ERCC4 rs744154 with bladder cancer, ERCC5 rs2296147 with esophageal cancer, ERCC5 rs17655 with laryngeal cancer and uterine cancer, and ERCC5 rs751402 with gastric cancer), moderate to six SNPs with a risk of eight cancers, and weak to nine SNPs with nine cancers. Data from ENCODE and other public databases showed that the loci of these SNPs with strong evidence might fall in putative functional regions. In conclusion, this paper summarizes comprehensive evidence that common variants of ERCC4 and ERCC5 genes are strongly associated with the risk of bladder cancer, esophageal cancer, laryngeal cancer, uterine cancer, and gastric cancer and elucidates the crucial role of the DNA repair genes in the genetic predisposition to human cancers.

ERCC5, HES6 and RORA are potential diagnostic markers of coronary artery disease

The mortality rate of patients with coronary artery disease (CAD) increases year by year, and the age of onset is decreasing, primarily because of the lack of an efficient and convenient diagnostic method for CAD. In the present study, we aimed to detect CAD-correlated biomarkers and the regulatory pathways involved through weighted co-expression network analysis. The microarray data originated from 93 CAD patients and 48 controls within the Gene Expression Omnibus (GEO) database. The gene network was implemented by weighted gene co-expression network analysis, and the genes were observed to fall into a range of modules. We took the intersection of genes in the modules most correlated with CAD with the differentially expressed genes of CAD, which were identified by applying the limma package. Lasso regression and support vector machine recursive feature elimination algorithms were used to determine CAD candidate signature genes. The biomarkers for diagnosing CAD were detected by validating candidate signature gene diagnostic capabilities (receiver operating characteristic curves) based on data sets from GEO. Three modules were selected, and 26 vital genes were identified. Eight of these genes were reported as the optimal candidate features in terms of CAD diagnosis. Through receiver operating characteristic curve analysis, we identified three genes (ERCC5, HES6 and RORA; area under the curve > 0.8) capable of distinguishing CAD from the control, and observed that these genes are correlated with the immune response. In summary, ERCC5, HES6 and RORA may have potential for diagnosis of CAD.

The link of ERCC2 rs13181 and ERCC4 rs2276466 polymorphisms with breast cancer in the Bangladeshi population

BACKGROUND

Breast cancer (BC) is the most common disease in women and the leading cause of death from cancer globally. Epidemiological studies examined that nucleotide excision repair genes ERCC2 (rs13181) and ERCC4 (rs2276466) SNPs might increase cancer risk. Based on the previous investigation, this study was conducted to explore the correlation between these polymorphisms and BC susceptibility in Bangladeshi women.

METHODS AND RESULTS

Between January 2019 and January 2020, 140 blood samples were collected from female patients histologically diagnosed with BC, and 111 female controls were recruited from non-cancer subjects. Genotyping was performed applying the PCR-RFLP method, and all statistical analyzes were conducted using SPSS, version 25.0. Comparison of characteristics and clinicopathological features between ERCC2 rs13181 and ERCC4 rs2276466 carriers and non-carriers showed no significant link with BC. Analysis of ERCC2 rs13181 with the risk of BC showed that the GG genotype and G allele carriers showed a fourfold and 1.78-fold higher risk (OR 4.00, P = 0.001 and OR 1.78, P = 0.002) that are statistically significant. In addition, the patients with combined TG+GG genotype revealed a 2.09-fold increased chance (OR 2.09, P = 0.020) BC development. Analysis of recessive model (GG vs. TT+TG) also depicted 2.74-times significantly higher risk (OR 2.74, P = 0.002). On the other hand, ERCC4 rs2276466 polymorphism did not show any significant association with BC (P > 0.05).

CONCLUSIONS

Our findings show that ERCC2 rs13181 is linked to an elevated risk of BC. Our study also shows that ERCC4 rs2276466 polymorphism has no substantial risk of BC in the Bangladeshi population.

Micronucleus, nucleoplasmic bridge and nuclear bud frequencies in patients with laryngeal carcinoma

The aim of the study is to determine and compare micronucleus (MN), nucleoplasmic bridge (NPB) and nuclear bud (NBUD) frequencies in patients with laryngeal carcinoma and healthy controls. The study was conducted in the School of Medicine of Onsekiz Mart University. A total of 102 volunteers, 51 of whom had laryngeal carcinoma and 51 of whom were healthy control subjects, participated in this study. The Cytokinesis-Block Micronucleus Assay (CBMN) was applied to peripheral blood lymphocytes taken from patients and controls. We evaluated MN, NPBs and NBUDs frequencies in patients with laryngeal carcinoma and compared the results with those in the control group. The frequencies of MN, NPBs and NBUDs of patients with laryngeal carcinoma were found significantly higher than those in the control group (P = 0.01, P = 0.004, P = 0.01, respectively). MN, NPB and NBUD frequencies were also compared in the patients with and without pesticide exposure, and the means of all frequencies was higher in patients with pesticide exposure (P = 0.001, P = 0.02 respectively). The MN, NPBs and NBUDs frequencies of the patients with laryngeal cancer were significantly higher than those of the control group, and pesticide exposure might be a risk factor that increases genomic instability and risk of laryngeal cancer.

XAB2 TagSNP Is Associated with the Risk of Gastric Cancer in Chinese Population: A Case-Control Study

XAB2 protein (xeroderma pigmentosum group A-binding protein 2) plays a significant role in the nucleotide excision repair pathway. Polymorphisms in the XAB2 gene may have an effect on the capability of DNA repair and further contribute to the risk of developing various cancers. In order to investigate the relationship between XAB2 genetic variants and the risk of gastric cancer, we performed a hospital-based case–control study. XAB2 tagSNPs were selected and then genotyped by iPlex Gold Genotyping Assay and Sequenom MassArray. By performing logistic regression analysis, odds ratio (OR) and 95% confidence interval (CI) were used to estimate the association of XAB2 tagSNPs with the risk of gastric cancer. Our results showed that XAB2 rs794078AA genotype was associated with a significantly lower risk of gastric cancer compared with GG genotype with OR (95% CI) of 0.33 (0.12–0.91). Stratified analysis indicated a significantly decreased risk for gastric cancer among smokers with rs794078AA genotype compared with nonsmokers with GG genotype (OR = 0.11, 95% CI = 0.01–0.91, p = 0.040). The gene–gene interactions by multifactor dimensionality reduction (MDR) showed that tagSNP rs794078 was the best predictive element for gastric cancers (Testing Bal. Acc = 51.68%, p = 0.055, cross-validation consistency = 9). Therefore, the XAB2 tagSNP rs794078 may play an important role in the development of gastric cancer.

Risk Factors and Genetic Biomarkers of Multiple Primary Cancers in Esophageal Cancer Patients

Esophageal cancer (EC) is a deadly cancer that frequently develops multiple primary cancers (MPCs). However, the risk biomarkers of MPC in EC have hardly been investigated. We retrospectively enrolled 920 subjects with primary EC and analyzed the possible risk factors as well as MPC single-nucleotide polymorphisms (SNPs) from blood DNA. A total of 184 subjects (20.0%) were confirmed to have MPC, 59 (32.8%) had synchronous MPC, and 128 (69.6%) had head and neck cancer. Elderly EC patients have an increased risk of having gastrointestinal cancer (Odds ratio, OR[95% CI]=6.70 [1.49-30.19], p=0.013) and a reduced risk of developing HNC (OR[95% CI]=0.44 [0.24-0.81], p=0.008). MPC risk was also associated with betel nut chewing (OR[95% CI]=1.63, 1.14-2.32], p=0.008), the A allele of ALDH2:rs671 (p=0.074 and 0.030 for GA and AA, respectively), the CC genotype in CISH:rs2239751 (OR[95% CI]=1.99 [1.2-3.32], p=0.008), and the G allele of ERCC5:rs17655 (p=0.001 and 0.090 for GC and CC, respectively). ADH1B:rs1229984 also correlated with MPC risk (p=0.117). Patients carrying four risk SNPs had a 40-fold risk of MPC (OR[95% CI]=40.25 [6.77-239.50], p<0.001) and a 12.57-fold risk of developing second primary cancer after EC (OR[95% CI]=12.57 [1.14-138.8], p=0.039) compared to those without any risk SNPs. In conclusion, hereditary variations in ALDH2, CISH, ERCC5, and ADH1B have great potential in predicting the incidence of MPC in EC patients. An extensive cancer screening program during clinical follow-up would be beneficial for patients with high MPC susceptibility.

A Nobel-Winning Scientist: Aziz Sancar and the Impact of his Work on the Molecular Pathology of Neoplastic Diseases

Aziz Sancar, Nobel Prize winning Turkish scientist, made several discoveries which had a major impact on molecular sciences, particularly disciplines that focus on carcinogenesis and cancer treatment, including molecular pathology. Cloning the photolyase gene, which was the initial step of his work on DNA repair mechanisms, discovery of the "Maxicell" method, explanation of the mechanism of nucleotide excision repair and transcription-coupled repair, discovery of "molecular matchmakers", and mapping human excision repair genes at single nucleotide resolution constitute his major research topics. Moreover, Sancar discovered the cryptochromes, the clock genes in humans, in 1998, and this discovery led to substantial progress in the understanding of the circadian clock and the introduction of the concept of "chrono-chemoterapy" for more effective therapy in cancer patients. This review focuses on Aziz Sancar's scientific studies and their reflections on molecular pathology of neoplastic diseases. While providing a new perspective for researchers working in the field of pathology and molecular pathology, this review is also an evidence of how basic sciences and clinical sciences complete each other.

Computational Prediction of Probable Single Nucleotide Polymorphism-Cancer Relationships

Genetic variations such as single nucleotide polymorphisms (SNPs) can cause susceptibility to cancer. Although thousands of genetic variants have been identified to be associated with different cancers, the molecular mechanisms of cancer remain unknown. There is not a particular dataset of relationships between cancer and SNPs, as a bipartite network, for computational analysis and prediction. Link prediction as a computational graph analysis method can help us to gain new insight into the network. In this article, after creating a network between cancer and SNPs using SNPedia and Cancer Research UK databases, we evaluated the computational link prediction methods to foresee new SNP-Cancer relationships. Results show that among the popular scoring methods based on network topology, for relation prediction, the preferential attachment (PA) algorithm is the most robust method according to computational and experimental evidence, and some of its computational predictions are corroborated in recent publications. According to the PA predictions, rs1801394-Non-small cell lung cancer, rs4880-Non-small cell lung cancer, and rs1805794-Colorectal cancer are some of the best probable SNP-Cancer associations that have not yet been mentioned in any published article, and they are the most probable candidates for additional laboratory and validation studies. Also, it is feasible to improve the predicting algorithms to produce new predictions in the future.

Microtubule associated protein 9 inhibits liver tumorigenesis by suppressing ERCC3

Background

Chromosomal instability plays an important part in cancer, but its genetic basis in liver tumorigenesis remains largely unclear. We aimed to characterize the mechanistic significance and clinical implication of mitotic regulator microtubule-associated protein 9 (MAP9) in hepatocellular carcinoma (HCC).

Methods

The biological functions of MAP9 were determined by in vitro tumorigenicity assays. Systematic MAP9 knockout mouse (MAP9^∆/∆) and hepatocyte-specific MAP9 knockout mouse (MAP9^∆/∆hep) were generated to confirm the role of MAP9 in HCC. The clinical impact of MAP9 was assessed in primary HCC tissue samples.

Findings

We found that MAP9 was frequently silenced in HCC tissue samples. The transcriptional silence of MAP9 in liver cancer cell lines and tissue samples was mediated by its promoter hypermethylation. MAP9 promoter hypermethylation or downregulation was associated with poor survival and recurrence in patients with HCC. Mechanistically, ectopic expression of MAP9 in LO2 and HepG2 cell lines impaired cell proliferation, colony formation, migration and invasion, and induced cell apoptosis and cycle arrest, whereas knockdown of MAP9 in Miha cell line showed the opposite effects. We found that MAP9^∆/∆ mice spontaneously developed a liver hyperplastic nodule and MAP9^∆/∆hep accelerated diethylnitrosamine-induced HCC formation. The tumour suppressive effect of MAP9 in HCC was mediated by downregulating excision repair cross-complementation group 3 (ERCC3), a nucleotide excision repair gene. Restoration of ERCC3 expression possessed an oncogenic potency and abrogated the tumour suppressive effects of MAP9.

Interpretation

MAP9 is a novel tumour suppressor in HCC by inhibiting ERCC3 expression, and serves as a prognostic factor in HCC patients.

Determination of SIRT1 rs12778366, FGFR2 rs2981582, STAT3 rs744166, and RAGE rs1800625 Single Gene Polymorphisms in Patients with Laryngeal Squamous Cell Carcinoma

Purpose

To determine the frequency of the genotype of signal transducer and activator of transcription protein 3 (STAT3) rs744166, sirtuin (SIRT1) rs12778366, fibroblast growth factor (FGFR2) rs2981582, and advanced glycosylation end product-specific receptor (RAGE) rs1800625 gene polymorphisms in patients with laryngeal squamous cell carcinoma (LSCC).

Methods

A total of 944 subjects were evaluated, which includes 144 patients with LSCC and 800 healthy controls. The genotyping of STAT3 rs744166, SIRT1 rs12778366, FGFR2 rs2981582, and RAGE rs1800625 was carried out using the RT-PCR.

Results

The analysis of STAT3 rs744166, SIRT1 rs12778366, and FGFR2 rs2981582 gene polymorphisms did not reveal any differences in genotype distribution between the patients with LSCC and the control subjects. However, statistical analysis revealed that genotypes (AA, AG, and GG) of rs1800625 in RAGE gene were distributed statistically significantly differently between patients and controls (61.1%, 30.6%, and 23.6% vs. 72.5%, 25.8%, and 1.8%, respectively; p < 0.001). Additionally, statistical significance was observed in allele distribution between these two groups, i.e., allele G at rs1800625 was more frequently observed in the patient group than in controls (23.6% vs. 14.6%; p < 0.001).

Conclusion

RAGE rs1800625 gene polymorphism may play a significant role in laryngeal squamous cell carcinoma development.

Alcohol Effects on Colon Epithelium are Time-Dependent

BACKGROUND

Alcohol intake increases the risk of developing colon cancer. Circadian disruption promotes alcohol's effect on colon carcinogenesis through unknown mechanisms. Alcohol's metabolites induce DNA damage, an early step in carcinogenesis. We assessed the effect of time of alcohol consumption on markers of tissue damage in the colonic epithelium.

METHODS

Mice were treated by alcohol or phosphate-buffered saline (PBS), at 4-hour intervals for 3 days, and their colons were analyzed for (i) proliferation (Ki67) and antiapoptosis (Bcl-2) markers, (ii) DNA damage (γ-H2AX), and (iii) the major acetaldehyde (AcH)-DNA adduct, N² -ethylidene-dG. To model circadian disruption, mice were shifted once weekly for 12 h and then were sacrificed at 4-hour intervals. Samples of mice with a dysfunctional molecular clock were analyzed. The dynamics of DNA damage repair from AcH treatment as well as role of xeroderma pigmentosum, complementation group A (XPA) in their repair were studied in vitro.

RESULTS

Proliferation and survival of colonic epithelium have daily rhythmicity. Alcohol induced colonic epithelium proliferation in a time-dependent manner, with a stronger effect during the light/rest period. Alcohol-associated DNA damage also occurred more when alcohol was given at light. Levels of DNA adduct did not vary by time, suggesting rather lower repair efficiency during the light versus dark. XPA gene expression, a key excision repair gene, was time-dependent, peaking at the beginning of the dark. XPA knockout colon epithelial cells were inefficient in repair of the DNA damage induced by alcohol's metabolite.

CONCLUSIONS

Time of day of alcohol intake may be an important determinant of colon tissue damage and carcinogenicity.

New insights into the association between AXIN2 148 C/T, 1365 C/T, and rs4791171 A/G variants and cancer risk

BACKGROUND

Many epidemiological studies have investigated association of AXIN2 variants on overall cancer risks; however, the available results remain inconsistent.

METHODS

An updated analysis was conducted to ascertain a more accurate estimation of the correlation between AXIN2 148 C/T, 1365 C/T, and rs4791171 A/G polymorphisms and cancer risk. We also used in silico tools to assess the effect of AXIN2 expression on cancer susceptibility and overall survival time.

RESULTS

A total of 4281 cases and 3955 control participants were studied. The overall results indicated that AXIN2 148 C/T variant was associated with cancer risk (allelic contrast: OR = 0.88, 95% CI 0.77-0.99, P heterogeneity = 0.004; dominant model: OR = 0.82, 95% CI 0.69-0.96, P heterogeneity = 0.022), especially for lung and prostate adenocarcinoma. Similar results were observed in 1365 C/T polymorphism (OR = 0.71, 95% CI 0.61-0.98, P heterogeneity = 0.873; dominant model: OR = 0.66, 95% CI 0.47-0.94, P heterogeneity = 0.775). Moreover, in subgroup analysis by ethnicity, similar findings were obtained for Asian and Caucasian populations. Results from in silico tools suggested that AXIN2 expressions in lung adenocarcinoma were lower than that in normal group.

CONCLUSIONS

Our findings indicated that AXIN2 148 C/T and 1365 C/T variants may be associated with decreased cancer susceptibility.

miR-506 is a YAP1-dependent tumor suppressor in laryngeal squamous cell carcinoma

Laryngeal squamous cell carcinoma (LSCC) accounts for 95% of laryngeal cancer incidence. Tobacco use has been shown to have a linear association with the development of the disease. While early diagnosis and treatment of LSCC are critical in improving the 5-year survival rate and quality of life, diagnosis of early-stage LSCC remains challenging because of the unapparent symptoms. Here, we report that miR-506, a critical regulator in many types of cancers, is aberrantly suppressed in LSCC patient tissues and cultured cancer cells. This is likely responsible for the enhanced production of YAP1 protein, a transcriptional factor that is well known for its oncogenic roles in LSCC malignancy. Statistical analysis has confirmed that the expression levels of miR-506 and YAP1 are strongly correlated with the malignant statuses of patient tumors. Restoring the expression level of miR-506 in cultured LSCC cells significantly inhibited proliferation, migration and invasion of the cells. The miR-506 and YAP1 regulatory network seems to affect at least pathways involved in apoptosis. Our study, for the first time, has demonstrated a tumor suppressive role of miR-506 in LSCC. This opens new opportunities for further exploring the molecular details of the development of the disease and thus will facilitate the development of novel diagnosis and therapeutic strategies.

Association of BER and NER pathway polymorphism haplotypes and micronucleus frequencies with global DNA methylation in benzene-exposed workers of China: Effects of DNA repair genes polymorphisms on genetic damage

OBJECTIVE

The base excision repair (BER) pathway and nucleotide excision repair (NER) pathway play important roles in the repair of benzene-induced genetic damage, and the effects of polymorphisms in these pathways on genetic damage and global DNA methylation are of great interest.

METHODS

Ten single nucleotide polymorphisms (SNPs) in the BER (XRCC1: rs25489, rs25487; APE1: rs1130409) and NER pathways (XPA: rs1800975; XPC: rs2228000, rs2228002; XPD: rs13181, rs1799793; XPG: rs17655; ERCC1: rs3212986) were analyzed by a Kompetitive allele-specific PCR (KASP) assay to find associations with cytokinesis-block micronucleus (MN) frequency and global DNA methylation in 294 shoe factory workers and 102 control participants.

RESULTS

Workers who possessed the following genotypes were associated with high MN frequency: rs25487 AA (FR (95% CI): 1.50 (1.16,1.9), p = 0.002, reference GG); rs1130409 GG (FR (95% CI): 1.28 (1.05,1.55), p = 0.010, reference TT); rs17655 GC (FR (95% CI): 1.18 (1.02,1.38), p = 0.038, reference GG); and rs3212986 TT (FR (95% CI): 1.55 (1.31,1.83), p < 0.001, reference GG). Workers with four and three mutant alleles showed 3.72-fold (OR (95% CI): 3.72 (1.34, 10.03), p = 0.009) and 2.48-fold (OR (95% CI): 2.48 (1.27, 4.88), p = 0.008) increased risk of genetic damage compared with workers with no or one mutant allele, and a dose-response relationship was found by the trend test (p = 0.006). The rs1130409 variant allele (GG+GT) was associated with low global DNA methylation (β=-0.20, 95% CI: -0.42, 0.03, p = 0.045).

CONCLUSION

In benzene-exposed workers, BER and NER pathway polymorphism haplotypes are associated with different levels of chromosome damage and had little effect on global DNA methylation.

DDB2 regulates Epithelial-to-Mesenchymal Transition (EMT) in Oral/Head and Neck Squamous Cell Carcinoma

DDB2 is a sensor of DNA damage and it plays an important role in Global Genomic Repair (GG-NER). Our previous studies show that DDB2 is involved in the regulation of metastasis in colon adenocarcinoma. Squamous Cell Carcinomas in the Oral/Head & Neck region (HNSCC) are particularly aggressive due to high incidence of recurrence and distant metastasis. In this study, we show that DDB2 expression is downregulated in advanced HNSCCs and loss of DDB2 expression coincides with reduced survival. Recent meta-analysis of gene expression data characterized the mesenchymal-type (EMT-type) as one most aggressive cancer cluster in HNSCC. Here, we report that DDB2 constitutively represses mRNA expression of the EMT- regulatory transcription factors SNAIL, ZEB1, and angiogenic factor VEGF in HNSCC cells. As a result, re-expression of DDB2 in metastatic cells reversed EMT with transcriptional upregulation of epithelial marker E-cadherin, and downregulation of mesenchymal markers N-cadherin, Vimentin, and Fibronectin. Interestingly, in a reverse assay, depletion of DDB2 in non-metastatic cells induced expression of the same EMT-regulatory transcription factors. TGFβs are major regulators of Snail and Zeb1, and we observed that DDB2 transcriptionally regulates expression of TGFB2 in HNSCC cells. Re-expression of DDB2 in mouse embryonic fibroblasts (MEFs) isolated from Ddb2 (-/-) knockout-mice resulted in repression of EMT-regulatory factors Zeb1, Snail and Tgfb2. Taken together, these results support the active role of DDB2 as a candidate suppressor of the EMT-process in HNSCC. Early detection leads to significantly higher survival in HNSCC and DDB2 expression in tumors can be a predictor of EMT progression.

An insight into clinical outcome of XPG polymorphisms in breast cancer

XPG polymorphisms are associated with varied clinical outcomes in different cancers but up-till now no study has been reported on breast cancer. Therefore, current study was aimed to explore the association of breast cancer risk factors and XPG polymorphisms (rs2296147 and rs1047768). It also investigated impact of XPG variants on overall survival and progression free survival among breast cancer cases. A total of 493 histopathologically identified breast cancer cases and 387 healthy females were genotyped by ARMS-PCR. Relationship between general characteristics, XPG polymorphisms and breast cancer risk was accessed by conditional logistic regression and illustrated by OR and 95% CI. Kaplan Meier test was applied to estimate survival distributions whereas log rank test demonstrated survival differences. Association of XPG variants with OS and PFS in breast cancer was illustrated by HR and 95% CI. Early onset of menopause, consanguinity and family history contributed (P < 0.05) towards breast cancer development. Both rs2296147 and rs1047768 SNPs were found to be associated (P < 0.05) with the risk of breast cancer. XPG rs1047768 was significantly associated with decreased PFS (HR 1.72; 95% CI 1.0-2.8) in breast cancer cases (P = 0.013) which was demonstrated by median time of 26 months for T > C variant when compared with median time of 37 months for TT genotype. No association was found between XPG rs2296147 polymorphism and survival analysis among breast cancer cases. XPG (rs1047768 T > C) variant may play a significant role in terms of decreased PFS and could be used as a predictor of unfavourable prognosis among breast cancer.

Association of XPA polymorphism with breast cancer risk: A meta-analysis

BACKGROUND

The association of XPA rs1800975 polymorphism with breast cancers has been reported in several studies, but the results were conflicting. In order to analyze the association between XPA rs1800975 polymorphism and the risk of breast cancer, a meta-analysis was performed in the present study.

METHODS

The literature search for relevant studies was conducted in PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Med Online databases. The odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were calculated using fixed-effect/random-effects models by the STATA 12.0 software. The sources of heterogeneity were analyzed by subgroup analysis.

RESULTS

Six case-control studies involving 5069 subjects (2338 patients and 2731 healthy controls) were included in the present meta-analysis. In the pooled analysis, no obvious association was found between XPA rs1800975 polymorphism and the risk of breast cancer in all genetic models. However, in subgroup analysis based on ethnicity, XPA rs1800975 polymorphism was found to be related to decreased breast cancer risk in non-Asians in the recessive model (OR = 0.80, 95% CI = 0.64-1.00, P = .045). Moreover, source of control subgroup analysis demonstrated that XPA rs1800975 polymorphism might decrease the risk of breast cancer in population-based group in the recessive model (OR = 0.80, 95% CI = 0.64-1.00, P = .045).

CONCLUSION

XPA rs1800975 polymorphism may decrease the risk of breast cancer in both non-Asians and population-based patients. Large sample size and well-designed study is needed for further assessing the role of XPA polymorphism in breast cancer risk.

XPG rs17655 G>C polymorphism associated with cancer risk: evidence from 60 studies

Xeroderma pigmentosum group G (XPG), a key component in nucleotide excision repair pathway, functions to cut DNA lesions during DNA repair. Genetic variations that alter DNA repair gene expression or function may decrease DNA repair ability and impair genome integrity, thereby predisposing to cancer. The association between XPG rs17655 G>C polymorphism and cancer risk has been investigated extensively, but the results remain contradictory. To get a more accurate conclusion, we performed a comprehensive meta-analysis of 60 case-control studies, involving 27,098 cancer cases and 30,535 healthy controls. Crude odds ratios (ORs) and 95% confidence interval (CIs) were calculated to determine the association of interest. Pooled analysis indicated that the XPG rs17655 G>C polymorphism increased the risk of overall cancer (CC vs. GG: OR=1.10, 95% CI=1.00-1.20; CG vs. GG: OR=1.06, 95% CI=1.02-1.11; CG+CC vs. GG: OR=1.07, 95% CI=1.02-1.12; C vs. G: OR=1.05, 95% CI=1.01-1.09). Stratification analysis by cancer type further showed that this polymorphism was associated with increased risk of gastric cancer and colorectal cancer. This meta-analysis indicated that the XPG gene rs17655 G>C polymorphism was associated with increased overall cancer risk, especially the risk of gastric cancer and colorectal cancer. Further validation experiments are needed to strength our conclusion.

Predictive value of XPG rs2296147T>C polymorphism on clinical outcomes of cancer patients

The Xeroderma pigmentosum complementation group G (XPG) rs2296147T>C polymorphism is suspected to associate with the clinical outcomes of cancer patients. However, the results are inconsistent. This meta-analysis aimed to evaluate the reliable predictive value of XPG rs2296147T>C polymorphism on clinical outcomes of cancer patients. A total of 11 eligible studies were enrolled in this meta-analysis. Our results indicated that the cancer patients with TT and CT genotypes were significantly associated with better respond rates when compared with the CC genotype (TT versus (vs.) CC: odds ratio (OR) = 2.05, 95% confidence intervals (CIs), 1.32-3.20, P = 0.002; TT+CT vs. CC: OR= 1.57, 95% CI, 1.14-2.17, P = 0.005). The TT genotype and/or T allele might be associated with higher survival time for cancer patients than the CC genotype and/or C allele. The cumulative meta-analyses showed an apparent beneficial objective response of TT genotype on cancer patients. In conclusion, this meta-analysis suggests that the XPG rs2296147T>C polymorphism is associated with the clinical outcomes of cancer patients. The XPG rs2296147T>C polymorphism might be a predictive factor of prognosis in cancers patients and contribute to individual treatment in the future.

ADH1B and CDH1 polymorphisms predict prognosis in male patients with non-metastatic laryngeal cancer

In this study, we assessed the association between single nucleotide polymorphisms (SNPs) in candidate genes and the prognosis of laryngeal cancer (LC) patients. Thirty-seven SNPs in 26 genes were genotyped in 170 male Han Chinese patients with LC. The effects of the candidate genes on the prognosis of LC patients were evaluated using Kaplan-Meier curves and Cox proportional hazards regression models. The GA genotype of rs1229984 (hazard ratio [HR], 0.537; 95% confidence interval [CI], 0.340-0.848; p = 0.008) in alcohol dehydrogenase 1B (ADH1B), and the AA genotype of rs9929218 (HR, 6.074; 95% CI, 1.426-25.870; p = 0.015) in CDH1 were associated with overall survival. Our data suggest that polymorphisms in ADH1B and CDH1 may be prognostic indicators in LC.

Association of Smoking and XPG, CYP1A1, OGG1, ERCC5, ERCC1, MMP2, and MMP9 Gene Polymorphisms with the early detection and occurrence of Laryngeal Squamous Carcinoma

A total of 200 smoking-related laryngeal carcinoma patients with pathology confirmation from the Eye and ENT Hospital and 190 high-risk smokers were included in a survey. All of the participants had a smoking index greater than 400 (cigarettes/day*year.) We obtained data on clinical and baseline characteristics, and peripheral blood was obtained and subjected to DNA extraction to analyse the correlation between smoking and the occurrence of laryngeal carcinoma. We selected candidate genes and SNP fragments that were found to be closely associated with smoking-related tumours in preliminary studies. The selected candidate genes were XPG, CYP1A1, OGG1, ERCC5, ERCC1, MMP2, and MMP9. We then performed SNP sequencing using Sequenom SNP detection technology. Target genes and single nucleotide polymorphism (SNP) fragments were evaluated to analyse the correlation between genotype or allele and smoking-related laryngeal carcinoma and to identify susceptibility genes related to laryngeal carcinoma. The results included four main findings: (1) The smoking index differed significantly between laryngeal cancer patients and control subjects (P=0.0035). The risk of laryngeal cancer was increased among individuals with a smoking index greater than 600 cigarettes/day*year (P=0.03). (2) The smoking index was significantly correlated with the T, N and clinical stages (P<0.05). (3) The polymorphisms CYP1A1-rs1048943, rs4646421, and rs4646422 and MMP9-rs17577 were significantly associated with laryngeal squamous carcinoma (P<0.05). (4) After stratifying the subjects by smoking degree, the GT genotype of ERCC1-rs2298881 was associated with a significantly greater risk of laryngeal carcinoma among heavy smokers (P=0.04). The results suggest that smoking plays an important role in the occurrence and development of laryngeal squamous carcinoma; CYP1A1 and MMP9 might be susceptibility gene SNPs for smoking-related laryngeal carcinoma, and ERCC1 might play an important role in heavy smokers. The results of this study might help identify an early marker for the detection and prevention of laryngeal carcinoma.

XPA gene polymorphisms and risk of neuroblastoma in Chinese children: a two-center case-control study

Neuroblastoma is a malignant tumor arising from the developing sympathetic nervous system, which mainly affects children. Variations in XPA gene have been shown to confer cancer susceptibility. However, no investigation has been reported regarding the association between XPA polymorphisms and neuroblastoma risk. This study was conducted to measure the association of XPA polymorphisms with neuroblastoma susceptibility in Chinese children. In this hospital-based case-control study with 393 cases and 812 controls, we genotyped two polymorphisms (rs1800975 T>C, and rs3176752 G>T) in XPA gene to access their contributions to neuroblastoma risk by TaqMan methods. The strength of the association with neuroblastoma risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs). No single polymorphism was found to predispose to neuroblastoma susceptibility. When risk genotypes were combined, we found that carriers of 1-2 risk genotypes had significantly increased neuroblastoma risk (adjusted OR=1.28; 95% CI=1.001-1.64, P=0.049), when compared to non-carriers. Stratification analysis by age, gender, sites of origin and clinical stages failed to show any significant association. Our study provides cues that XPA gene polymorphisms may exert a weak effect in neuroblastoma risk. This finding needs further validations by larger sample size studies.

The association between XPG polymorphisms and cancer susceptibility: Evidence from observational studies

BACKGROUND

Exposure to environmental carcinogens can cause damages to DNA. If not properly repaired, the DNA damages may increase the risk of carcinogenesis. Xeroderma pigmentosum group G (XPG) gene is an essential gene in the nucleotide excision repair (NER) pathway. The association between XPG polymorphisms and cancer susceptibility has been the focus of attention in the molecular epidemiology of cancer. However, the conclusions have been divergent. Therefore, we conducted a comprehensive meta-analysis to precisely evaluate the association of 3 frequently investigated XPG polymorphisms (rs751402, rs873601, and rs2296147) with cancer risk.

METHODS

Pubmed, EMBASE, and Chinese National Knowledge Infrastructure (CNKI) were searched for relevant studies in English and Chinese. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the association between XPG polymorphisms (rs751402, rs873601, and rs2296147) and cancer risk.

RESULTS

Twenty-three studies were included. Overall, there was no significant association between rs751402 polymorphism and overall cancer risk under the 5 gene models. However, we observed strong correlation between rs751402 polymorphism and gastric cancer (C vs T: OR=1.21, 95% CI = 1.00-1.26, P = .045; TC vs CC: OR = 1.12, 95% CI = 1.00-1.24, P = .041; TC/TT vs CC: OR = 1.13, 95% CI = 1.02-1.26, P = .020). There was a significant correlation between rs873601 polymorphism and cancer risk under the homozygous model (GG vs AA: OR = 1.16, 95% CI = 1.07-1.26, P = .001). Moreover, significant association with breast cancer was detected for rs873601 polymorphism under the allele contrast model (G vs A: OR = 1.10, 95% CI = 1.02-1.20, P = .021). In the subgroup of Asian, rs873601 polymorphism was related to the susceptibility to cancer (G vs A: OR = 1.07, 95% CI = 1.03-1.12, P = .010; GG vs AA: OR = 1.15, 95% CI = 1.06-1.26, P = .001; AG/AA vs GG: OR = 1.08, 95% CI = 1.01-1.15, P = .031; AA vs AG/GG: OR = 1.13, 95% CI = 1.05-1.21, P = .001). Significant association between rs2296147 polymorphism and cancer risk were observed in Asian population (CT vs TT: OR = 0.93, 95% CI = 0.87-0.99, P = .036).

CONCLUSIONS

Our meta-analysis suggested that the rs873601 polymorphism was significantly associated with overall cancer risk. The moderate effects of rs751402 and rs2296147 polymorphism on cancer susceptibility might be highly dependent on cancer type and ethnicity, respectively. Large studies are needed to validate our findings, especially in Caucasian and African population.

Haplotype analysis on relationship of ERCC2 and ERCC3 gene polymorphisms with osteosarcoma risk in Chinese young population

The purpose of the study was to investigate the association of single-nucleotide polymorphisms (SNPs) within excision repair cross-complementation (ERCC) gene polymorphisms, additional gene-gene interaction, and haplotype combination with osteosarcoma risk. Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among SNPs. Logistic regression was performed to investigate the association between six SNPs within ERCC gene, additional gene-gene interaction on osteosarcoma risk. Haplotype analysis was performed using SNPstats ( http://bioinfo.iconcologia.net/SNPstats ). Osteosarcoma risk was significantly higher in carriers with the T allele of ERCC2-rs1799793 than those with GG genotype (GT+ TT vs. GG), adjusted OR (95% CI) = 1.56 (1.13-2.01), and higher in carriers with the A allele of ERCC3-rs4150441 than those with GG genotype (GA+ AA vs. GG), adjusted OR (95% CI) = 1.63 (1.25-2.09). GMDR model indicated a significant two-locus model (p = 0.0107) involving rs1799793 and rs4150441; cross-validation consistency of the two-locus model was 9/10; and the testing accuracy was 60.11%. Participants rs1799793-GT or -TT and rs4150441-GA or -AA genotype have the highest osteosarcoma risk, compared to subjects with rs1799793-GG and rs4150441-GG genotype, OR (95% CI) = 2.87 (1.21-4.63), after covariates adjustment. Haplotype containing the rs1799793-T and rs11615-T alleles was associated with a statistically increased osteosarcoma risk, OR (95% CI) = 1.47 (1.12-1.92). We found that the T allele of ERCC2-rs1799793 and the A allele of ERCC3-rs4150441, interaction between rs1799793 and rs4150441, and haplotype containing the rs1799793T and rs11615-T alleles were all associated with increased osteosarcoma risk.

Modulation of Colorectal Cancer Risk by Polymorphisms in 51Gln/His, 64Ile/Val, and 148Asp/Glu of APEX Gene; 23Gly/Ala of XPA Gene; and 689Ser/Arg of ERCC4 Gene

Polymorphisms in DNA repair genes may affect the activity of the BER (base excision repair) and NER (nucleotide excision repair) systems. Using DNA isolated from blood taken from patients (n = 312) and a control group (n = 320) with CRC, we have analyzed the polymorphisms of selected DNA repair genes and we have demonstrated that genotypes 51Gln/His and 148Asp/Glu of APEX gene and 23Gly/Ala of XPA gene may increase the risk of colorectal cancer. At the same time analyzing the gene-gene interactions, we suggest the thesis that the main factor to be considered when analyzing the impact of polymorphisms on the risk of malignant transformation should be intergenic interactions. Moreover, we are suggesting that some polymorphisms may have impact not only on the malignant transformation but also on the stage of the tumor.

Characteristics of cigarette smoking without alcohol consumption and laryngeal cancer: overall and time-risk relation. A meta-analysis of observational studies

Tobacco smoking was one of the risk factors for upper aerodigestive tract cancer, but exclusive quantification of the impact of cigarette smoking on laryngeal cancer had not been investigated. A meta-analysis of researches that had reported quantitative estimates of cigarette smoking and risk of laryngeal cancer by March 2016 was performed. Pooled estimates of relative risks and their 95% confidence intervals were obtained and summarized. Sensitivity analysis and subgroup analysis were implemented to find out sources of research heterogeneity and the effect of potential confounders. Publication bias was investigated and corrected if found to be present through Egger's and Begg's test, and trim and fill algorithm. Thirty researches based on a total of 14,292 cases from three cohort and fifteen case-control studies were included and pooled estimate for the correlation between cigarette smoking and the risk of laryngeal cancer was 7.01 (95% confidence interval 5.56-8.85), with moderate heterogeneity across the researches (I ² = 56.7%, p = 0.002). The RRs were 5.04 (95% CI 3.09-8.22) for cohort studies (p = 0.121), 7.59 (95% CI 5.86-9.82) for case-control studies (p = 0.005). The risk kept elevated within the first fifteen years of quitting smoking(RR 3.62, 95% CI 1.88-7.00) but dropped in the 16 years and more after smoking cessation(RR 1.88, 95% CI 1.16-3.05). Individuals who smoked with 40 or more pack-years had nine times the risk of laryngeal cancer(RR 9.14; 95% CI 6.24-13.39). Subjects who smoked 30 or more cigarettes a day had sevenfolds the risk of laryngeal cancer (RR 7.02; 95% CI 4.47-11.02) and who smoked 40 or more years had five times the risk versus never smokers (RR 5.76; 95% CI 3.69-8.99). Evidence of publication bias was not detected for the correlation between current cigarette smoking and risk of laryngeal cancer (p = 0.225 with Begg's test, p = 0.317 with Egger's test). The results demonstrated strong correlation referring to dose-response and time-response between cigarette smoking and risk of laryngeal cancer for both men and women. The probability of developing laryngeal cancer was decreased by quitting smoking, particularly among former cigarette smokers who had stopped smoking for 15 or more years. The subgroup analysis demonstrated that study type influenced the RRs estimates of the studies.

Gene-environment interactions between ERCC2, ERCC3, XRCC1 and cadmium exposure in nasal polyposis disease

Gene-environment interactions have long been known to play an important role in complex disease aetiology, such as nasal polyposis (NP). The present study supports the concept that DNA repair gene polymorphisms play critical roles in modifying individual susceptibility to environmental diseases. In fact, we investigated the role of polymorphisms in DNA repair genes and cadmium as risk factors for Tunisian patients with NP. To the best of our knowledge, this is the first report on the impact of combined effects of cadmium and ERCC3 7122 A>G (rs4150407), ERCC2 Lys751Gln (rs13181) and XRCC1 Arg399Gln (rs25487) genes in the susceptibility to NP disease. Significant associations between the risk of developing NP disease and ERCC2 [odds ratio (OR) = 2.0, 95 % confidence interval (CI) = 1.1-3.7, p = 0.023] and ERCC3 (OR = 2.2, 95 % CI = 1.2-4.1, p = 0.013) genotypes polymorphisms were observed. Blood concentrations of Cd in NP patients (2.2 μg/L) were significantly higher than those of controls (0.5 μg/L). A significant interaction between ERCC3 (7122 A>G) polymorphism and blood-Cd levels (for the median of blood-Cd levels: OR = 3.8, 95 % CI = 1.3-10.8, p = 0.014 and for the 75th percentiles of blood-Cd levels: OR = 2.7, 95 % CI = 1.1-7.2, p = 0.041) was found in association with the risk of NP disease. In addition, when we stratified ERCC2, ERCC3 and XRCC1 polymorphism genotypes by the median and 75th percentiles of blood-Cd levels, we found also significant interactions between ERCC2 (Lys751Gln) and ERCC3 (7122 A>G) genotypes polymorphism and this metal in association with NP disease. However, no interaction was found between XRCC1 (Arg399Gln) polymorphism genotypes and Cd in association with NP disease.

A genetic view of laryngeal cancer heterogeneity

During the recent decades significant improvements in the understanding of laryngeal molecular biology allowed a better characterization of the tumor. However, despite increased molecular knowledge and clinical efforts, survival of patients with laryngeal cancer remains the same as 30 years ago. Although this result may not make major conclusions as preservation approaches were not broadly used until the time of database collection, it seems to be clear that there is still window for improvement. Although the cornerstone for laryngeal cancer eradication is to implement smoking cessation programs, survival progresses will be hopefully seen in the future. Introducing molecular biomarkers as predictive factors to determine which patients will benefit of preservation treatments may become one of the next steps to improve survival. Furthermore, the development of new therapeutic modalities joint to biomarkers to selectively apply such new therapy in these patients may help to define new modalities with improved survival. New inhibitors against Notch pathway, EGFR, VRK1 or DNA damage repair may become gold standard if we are able to identify patients that may benefit from them, either on survival or functional larynx preservation. It is the moment for an inflexion point on the way laryngeal cancer is clinically managed.

Increased expression of ERCC2 gene in head and neck cancer is associated with aggressive tumors: a systematic review and case-control study

INTRODUCTION

The excision repair cross-complementation group 2 (ERCC2) ATP-dependent helicase is an essential member of the DNA repair pathway. It has been observed to be differentially expressed in different cancers, which shows its involvement in carcinogenesis.

AIM

In the present study we have tried to determine the association of expression patterns of this gene with head and neck carcinogenesis.

METHOD

We first carried out a systematic review of the available studies on the role of ERCC2 in head and neck cancer (HNC). In order to test the hypothesis that the expression patterns of XPD/ERCC2 play a critical role in HNC pathogenesis, we then conducted a population based case-control study on 81 head and neck tumor samples and adjacent normal-tissue control samples. Reverse transcriptase polymerase chain reaction (RT-PCR) and quantitative polymerase chain reaction (qPCR) were used to assess ERCC2 deregulation at the mRNA level.

RESULT

Expression analysis showed that the ERCC2 expression level was significantly upregulated (p<0.05) in HNC tissues compared with adjacent normal tissues. Furthermore, the expression pattern of ERCC2 was correlated with the expression pattern of Ki-67 and a significant correlation (r = 0.230, p<0.03) was observed between ERCC2 and Ki-67. Spearman's correlation also showed a significant correlation between ERCC2 expression and tumor stage (r = 0.271, p<0.02) and grade (r = 0.228, p<0.02) of HNC.

CONCLUSIONS

Our data suggest that deregulation of ERCC2 in HNC has the potential to predict a more aggressive cancer phenotype and may be considered a possible biomarker for improved diagnosis and prognosis of HNC.

Genetic Association between the XPG Asp1104His Polymorphism and Head and Neck Cancer Susceptibility: Evidence Based on a Meta-Analysis

BACKGROUND

Previous studies evaluating the association between the xeroderma pigmentosum group G (XPG) Asp1104His polymorphism and head and neck cancer susceptibility have proven controversial. This meta-analysis of the literature was performed to obtain a more precise estimation of the relationship.

MATERIALS AND METHODS

We systematically searched PubMed, Embase and Web of Science with a time limit of Dec 18, 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of any association.

RESULTS

We performed a meta-analysis of eight published case-control studies, including 3,621 cases and 5,475 controls. Overall, no significant association was found between the XPG Asp1104His polymorphism and head and neck cancer susceptibility under all genetic models. In the subgroup analysis by ethnicity, the XPG Asp1104His polymorphism had statistically significant association with elevated head and neck cancer risk under CC vs GG (OR=1.24, 95% CI=1.00~1.54) and the recessive model (OR=1.22, 95%CI=1.01~1.46) in Asian populations. A similar result was found under CC vs GG (OR =1.22, 95%CI =1.01~1.47) in the population based subgroup by source of control. When performed by tumor site, the XPG Asp1104His polymorphism had statistically significant association with elevated laryngeal cancer under all genetic models (CC vs GG: OR=1.59, 95% CI=1.16~2.19; GC vs GG: OR=1.38, 95%CI=1.10~1.72; dominant model: OR=1.42, 95% CI=1.15~1.74; recessive model: OR=1.36, 95% CI=1.02~1.81).

CONCLUSIONS

This meta-analysis suggested that the XPG Asp1104His polymorphism is a risk factor for head and neck cancer susceptibility, especially for laryngeal cancer and in Asian populations.

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.

Interaction between MLL3 genetic polymorphisms, smoking, and alcohol drinking in laryngeal cancer: a case-control study

A previous study indicated that MLL3 genetic polymorphisms were associated with human cancer. However, whether MLL3 genetic variants are associated with the risk of laryngeal cancer is not clear. This study investigated the association between MLL3 gene polymorphisms and laryngeal cancer in a Chinese population. Four polymorphisms of the MLL3 gene (rs6943984, rs4725443, rs3800836, rs6464211) were genotyped using the TaqMan method in 592 patients with larynx cancer and 602 age- and sex-matched noncancer controls. We found that rs6943984 and rs4725443 of the MLL3 gene were significantly associated with the risk of larynx cancer after Bonferroni correction. The minor allele A for rs6943984 was associated with increased larynx cancer risk (P < 0.001, OR = 1.960, 95% CI = 1.587-2.420). C allele frequency (0.151) for rs4725443 was significantly higher in the case group than the control group (0.072, P < 0.001). Haplotype analyses showed that haplotypes A-T-A-C and G-T-G-C increased the risk of laryngeal cancer (OR = 2.406, 95% CI: 1.820-3.180, P < 0.001; OR = 1.399, 95% CI: 1.180-1.659, respectively), and haplotypes G-T-A-C and G-T-G-T significantly reduced the risk of laryngeal cancer (OR = 0.332, 95% CI: 0.271-0.408, P < 0.001; OR = 0.742, 95% CI: 0.607-0.908, respectively). We also found that MLL3 rs6943984 and rs4725443 polymorphisms had synergistic effects with smoking or alcohol drinking for the risk of laryngeal cancer. This study indicated that MLL3 genetic polymorphisms and haplotypes were associated with larynx cancer in a Chinese population. There was a mutually synergistic effect between smoking, alcohol drinking, and MLL3 gene polymorphisms for laryngeal cancer.

Association between UGT1A1 Polymorphism and Risk of Laryngeal Squamous Cell Carcinoma

Laryngeal cancer is one of the largest subgroups of head and neck cancers. In addition to smoking and alcohol consumption, genetic polymorphisms are also risk factors for the development of laryngeal cancer. However, the exact relation between genetic variants and pathogenesis of laryngeal cancer has remained elusive. The aim of this study was to examine UGT1A1*6 (rs4148323 A/G) polymorphisms in 103 patients with laryngeal cancer and 220 controls using the high resolution melting curve (HRM) technique and to explore the association between UGT1A1*6 (rs4148323 A/G) polymorphisms and laryngeal cancer. The results showed an association between the rs4148323 G allele and increased risk of laryngeal cancer. While there was no statistically significant difference between rs4148323 genotype frequencies and different histological grades or different clinical stages of laryngeal cancer, stratification analysis indicated smoking or alcohol consumption and rs4148323 G allele combined to increase the risk of laryngeal cancer. In conclusion, the rs4148323 G allele is associated with the high UGT1A1 enzyme activity, and might increase the risk of laryngeal cancer. Furthermore, smoking or alcohol consumption and the rs4148323 G allele act synergistically to increase the risk of laryngeal cancer.

A Comprehensive Analysis of Influence ERCC Polymorphisms Confer on the Development of Brain Tumors

Within DNA repair genes, there lie a number of single nucleotide polymorphisms that may impair protein function and attenuate DNA repair capability, resulting in genomic instability and individual predisposition to malignancies. The purpose of this study was to assess the previously reported inconsistent association of polymorphisms in ERCC1 (rs11615, rs3212986), ERCC2 (rs13181, rs1799793, rs238406), and ERCC5 (rs17655) with the development of brain tumors. In the present work, we carried out a comprehensive meta-analysis of results from all published data (5 data sets for rs11615, 7 for rs3212986, 11 for rs13181, 5 for rs1799793, 3 for rs238406, and 4 for rs17655) to evaluate risk of brain tumors contributed by the polymorphisms being investigated. Either the analytic method described by Mantel and Haenszel or that proposed by DerSimonian and Laird was properly used to summarize the risk estimates (OR and 95% CI). Data analyses were done with Stata version 12.0. Meta-analyses were performed for all polymorphisms, and only rs3212986 in the ERCC1 gene showed a significant association with glioma incidence. In the homozygote comparison, we found 1.26-fold elevated risk of glioma in relation to presence of the AA genotype (OR = 1.26, 95% CI = 1.05-1.52, P OR = 0.013, P heterogeneity = 0.849, I(2) = 0.0%). We also noted that individuals with the rs3212986-AA as compared to those with rs3212986-CC/CA had a 28% higher risk to develop glioma (OR = 1.28, 95% CI = 1.06-1.53, P OR = 0.008, Pheterogeneity = 0.808, I(2) = 0.0%). No major effects were observed for Caucasians or Asians in subgroup analysis by ethnicity. ERCC1 rs3212986 is a common single nucleotide polymorphism and may contribute toward individual susceptibility for glioma. Further research in this filed is required to verify the association obtained based on a relatively small number.

Single nucleotide polymorphisms of nucleotide excision repair and homologous recombination repair pathways and their role in the risk of osteosarcoma

Objective:

To evaluate the influence of polymorphisms in nucleotide excision repair (NER) and homologous recombination repair (HRR) pathways on the development of osteosarcoma patients.

Methods:

Genotypes of ERCC1 rs11615 and rs3212986, ERCC2 rs1799793 and rs13181, NBN rs709816 and rs1805794, RAD51 rs1801320, rs1801321 and rs12593359, and XRCC3 rs861539 were conducted by Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP) assay.

Results:

Total 148 osteosarcoma patients and 296 control subjects were collected from Taizhou First People’s Hospital. Conditional logistic regression analyses found that individuals carrying with GA+AA genotype of ERCC2 rs1799793 and GC+CC genotype of NBN rs1805794 were significantly associated with increased risk of osteosarcoma, and the ORs(95%CI) were 1.58(1.03-2.41) and 2.66(1.73-4.08), respectively. We found that GA+AA genotype of ERCC2 rs1799793 or GC+CC genotype of NBN rs1805794 were associated with an increased risk of osteosarcoma in females, with ORs(95%CI) of 2.42(1.20-4.87) and 2.01(1.07-4.23), respectively.

Conclusion:

Our results suggest that ERCC2 rs1799793 and NBN rs1805794 polymorphisms were associated with an increased risk for osteosarcoma, which suggests that NER and HRR pathways modulate the risk of developing osteosarcoma.

Genetic variation affects congenital heart defect susceptibility in offspring exposed to maternal tobacco use

BACKGROUND

Congenital heart defects (CHDs) are among the most prevalent and serious birth defects, occurring in 8 to 10 of every 1000 live births in the United States. Epidemiologic studies have reported an association between CHDs and maternal smoking, but it remains unknown how genes impact the susceptibility of offspring to CHDs in the presence of maternal tobacco use.

METHODS

Using data from 403 case- and 219 control-parental triads enrolled in the National Birth Defects Prevention Study between 1998 and 2008, we investigated the association between CHDs and maternal and infant genetic variants involved in the tobacco metabolism and DNA repair pathways among mothers who smoked prenatally.

RESULTS

The maternal genotypes of single nucleotide polymorphisms in the excision repair cross-complementation group 1 (ERCC1), poly (ADP-ribose) polymerase 2 (PARP2), and ERCC5 genes were identified to be significantly associated with the occurrence of CHDs in the presence of maternal tobacco use. Our analysis also revealed a moderate association between the infant genotypes of polymorphisms in the O-sialoglycoprotein endopeptidase (OSGEP) gene and increased risk of CHDs among mothers who smoked.

CONCLUSION

Our study provides evidence that maternal and infant polymorphisms within the ERCC1, PARP2, ERCC5, and OSGEP genes are associated with CHD risk in the presence of maternal tobacco use. These results may provide insight into the susceptibility of having a pregnancy affected by CHDs among women who smoke.

Association of ERCC1 polymorphisms (rs3212986 and rs11615) with the risk of head and neck carcinomas based on case-control studies

PURPOSE

Current data regarding association between ERCC1 polymorphisms and the risk of head and neck squamous cell carcinomas (HNSCC) have shown controversial results. The current study aims to achieve a more accurate estimation of the association between two well-characterized ERCC1 polymorphisms (rs3212986 and rs11615) and HNSCC risk by a meta-analysis of all eligible studies.

METHODS

The meta-analysis was performed by reviewing seven studies on the ERCC1 C8092A (rs3212986) polymorphism including 2055 cases and 2635 controls and four studies on the T19007C (rs11615) polymorphism including 910 cases and 1337 controls.

RESULTS

For ERCC1 rs3212986 polymorphism, no significant association with HNSCC was found in overall analysis, but subgroup analysis revealed that a significant association of the rs3212986 polymorphism was found among Asians (A vs. C: OR 0.83; 95% CI 0.70-0.99) but not Caucasians. For ERCC1 rs11615 polymorphism, a significant association with HNSCC (TC + CC vs. TT: OR 1.23; 95% CI 1.03-1.47) was found in overall analysis. Consistently, subgroup analysis revealed that significant associations of the rs3212986 polymorphism were found among Asians (C vs. T: OR 1.32; 95% CI 1.04-1.69) and in laryngeal carcinoma (CC vs. TC + TT: OR 1.32; 95% CI 1.02-1.72).

CONCLUSION

The findings of the meta-analysis indicated that a decreased risk for the ERCC1 rs3212986 polymorphism was found among Asians, and an increased risk for the ERCC1 rs11615 polymorphism was found in overall HNSCC, especially in Asian subgroup and laryngeal site, suggesting that ERCC1 rs3212986 polymorphism in Asians may act as a protective factor and rs11615 polymorphism may be a risk factor for HNSCC.

Association of the XPA A23G polymorphism with the risk of head and neck carcinomas: Evidence from 5,491 subjects

The XPA gene participates in modulating DNA damage recognition during the DNA nucleotide excision repair process. Current data regarding the association of the XPA A23G polymorphism with the risk of head and neck squamous cell carcinoma (HNSCC) remain controversial, and meta-analyses focusing on the HNSCC risk and this polymorphism are limited. Therefore, the aim of the present study was to derive a more precise estimation of this association by a meta-analysis of all the eligible studies. Odds ratios (ORs) with 95% confidence intervals (CI) were assessed for the strength of the associations in eight studies, including 5,491 subjects (2,409 HNSCC cases and 3,082 controls). The overall analysis revealed that the XPA A23G polymorphism was not significantly associated with the overall HNSCC risk. Consistently, there was no evidence for the association between the XPA A23G polymorphism and HNSCC risk in subgroup analyses based on ethnicity and the source of controls. However, the significant associations in oral carcinoma with the increased risk among the XPA heterozygote (AG vs. AA: OR, 1.58; 95% CI, 1.06-2.37; P_{heterogeneity}=0.23, I²=30%) and dominant (AG +GG vs. AA: OR, 1.53; 95% CI, 1.04-2.23; P_{heterogeneity}=0.21, I²=36%) models were observed in the subgroup analysis by tumor site. In conclusion, the meta-analysis suggested that the XPA A23G polymorphism was not associated with overall HNSCC susceptibility, but it was associated with oral carcinoma susceptibility and it may be a risk factor for oral carcinoma. Further well-designed and large studies are required to confirm these associations.

Complete mitochondrial genome sequence and mutations of the laryngeal cancer model inbred nude rat strain

In the present work, we undertook the complete mitochondrial genome sequencing of an important laryngeal cancer model inbred rat strain for the first time. The total length of the mitogenome was 16,308 bp. It harbored 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and one non-coding control region (D-loop region). The mutation events were also reported.

ERCC polymorphisms and prognosis of patients with osteosarcoma

Osteosarcoma is the most common primary bone malignancy in children and teenagers, and its clinical outcome remains poor. Previous studies have investigated the association between excision repair cross-complementing (ERCC) and prognosis of osteosarcoma patients, but their results were inconsistent. We aimed to clarify the associations between ERCC polymorphisms and osteosarcoma prognosis by using meta-analysis. We searched relevant studies in PubMed, Embase, coupled with Chinese National Knowledge Infrastructure (CNKI) in human osteosarcoma published prior to April, 2014. Hazard ratios (HR) together with their 95 % confidence intervals (95 % CI) were used to measure the relationship between ERCC mutations and prognosis in patients with osteosarcoma. Pooled results showed that polymorphism of ERCC2 Lys751Gln was associated with the overall survival of osteosarcoma (GG vs. AA, HR = 0.40; 95 % CI 0.18-0.86), and ERCC5 His46His mutation was associated with the event-free survival of osteosarcoma (CC vs. TT, HR = 0.37; 95 % CI 0.15, 0.93). In addition, there is no evidence of association on ERCC1 Asn118Asn, ERCC1 Gln504Lys, and ERCC2 Asp312Asn polymorphisms with prognosis in osteosarcoma. In summary, the ERCC2 Lys751Gln and ERCC5 His46His polymorphisms might influence osteosarcoma prognosis.