Overexpression of NAT10 induced platinum drugs resistance in breast cancer cell / 中华肿瘤杂志

Objective: To observe the platinum drugs resistance effect of N-acetyltransferase 10 (NAT10) overexpression in breast cancer cell line and elucidate the underlining mechanisms. Methods: The experiment was divided into wild-type (MCF-7 wild-type cells without any treatment) group, NAT10 overexpression group (H-NAT10 plasmid transfected into MCF-7 cells) and NAT10 knockdown group (SH-NAT10 plasmid transfected into MCF-7 cells). The invasion was detected by Transwell array, the interaction between NAT10 and PARP1 was detected by co-immunoprecipitation. The impact of NAT10 overexpression or knockdown on the acetylation level of PARP1 and its half-life was also determined. Immunostaining and IP array were used to detect the recruitment of DNA damage repair protein by acetylated PARP1. Flow cytometry was used to detect the cell apoptosis. Results: Transwell invasion assay showed that the number of cell invasion was 483.00±46.90 in the NAT10 overexpression group, 469.00±40.50 in the NAT10 knockdown group, and 445.00±35.50 in the MCF-7 wild-type cells, and the differences were not statistically significant (P>0.05). In the presence of 10 μmol/L oxaliplatin, the number of cell invasion was 502.00±45.60 in the NAT10 overexpression group and 105.00±20.50 in the NAT10 knockdown group, both statistically significant (P<0.05) compared with 219.00±31.50 in wild-type cells. In the presence of 10 μmol/L oxaliplatin, NAT10 overexpression enhanced the binding of PARP1 to NAT10 compared with wild-type cells, whereas the use of the NAT10 inhibitor Remodelin inhibited the mutual binding of the two. Overexpression of NAT10 induced PARP1 acetylation followed by increased PARP1 binding to XRCC1, and knockdown of NAT10 expression reduced PARP1 binding to XRCC1. Overexpression of NAT10 enhanced PARP1 binding to LIG3, while knockdown of NAT10 expression decreased PARP1 binding to LIG3. In 10 μmol/L oxaliplatin-treated cells, the γH2AX expression level was 0.38±0.02 in NAT10 overexpressing cells and 1.36±0.15 in NAT10 knockdown cells, both statistically significant (P<0.05) compared with 1.00±0.00 in wild-type cells. In 10 μmol/L oxaliplatin treated cells, the apoptosis rate was (6.54±0.68)% in the NAT10 overexpression group and (12.98±2.54)% in the NAT10 knockdown group, both of which were statistically significant (P<0.05) compared with (9.67±0.37)% in wild-type cells. Conclusion: NAT10 overexpression enhances the binding of NAT10 to PARP1 and promotes the acetylation of PARP1, which in turn prolongs the half-life of PARP1, thus enhancing PARP1 recruitment of DNA damage repair related proteins to the damage sites, promoting DNA damage repair and ultimately the survival of breast cancer cells.

Immunohistochemical expression of DNA repair proteins in oral tongue and lower lip squamous cell carcinoma

Abstract The DNA repair system involves genes and proteins that are essential for the maintenance of genome integrity and the consequent control of various cellular processes. Alterations in these genes and proteins play a role in tumor development and progression and might be associated with prognosis. The aims of this study were to analyze the immunoexpression of two DNA repair proteins, XPF and XRCC1, in lower lip squamous cell carcinoma (LLSCC) and oral tongue squamous cell carcinoma (OTSCC), and to investigate possible associations with clinical and histopathological parameters. The immunohistochemical expression of XPF and XRCC1 was analyzed semi-quantitatively in 40 cases each of LLSCC and OTSCC. The chi-squared test or Fisher's exact test, when appropriate, was used to investigate the association between expression of the proteins and clinicopathological characteristics. The cytoplasmic immunoexpression of XPF was high in OTSCC (95% of the cases analyzed) but low in LLSCC (52.5%). Among the clinicopathological parameters evaluated, a statistically significant association was observed between high nuclear expression of XRCC1 and the absence of regional lymph node metastasis in patients diagnosed with OTSCC (p=0.006). The high protein expression of XPF and XRCC1 in OTSCC and LLSCC suggests an important role in the development and progression of these tumors. Our study found an association between high nuclear expression of XRCC1 and the absence of loco-regional metastasis in cases diagnosed as OTSCC, suggesting a role of this protein in tumor progression.

Análise da imunoexpressão de proteínas de reparo do DNA envolvidas nas vias BER e NER em lesões odontogênicas epiteliais benignas / Immunoexpression analysis of DNA repair proteins involved in BER and NER pathways in benign epithelial odontogenic lesions

As lesões odontogênicas epiteliais benignas apresentam comportamento biológico heterogêneo e patogênese ainda não totalmente esclarecida. As vias de reparo do ácido desoxirribonucleico (DNA) atuam em tipos específicos de danos ao material genético, realizando o reparo e regulando diversos processos celulares. Dentre as principais vias de reparo do DNA, destacamse o reparo por excisão de bases (BER) e o reparo por excisão de nucleotídeos (NER). Investigações têm demonstrado que as proteínas envolvidas nessas vias se encontram desreguladas e, por vezes, altamente expressas em algumas neoplasias malignas, contribuindo para a progressão tumoral. Levando em consideração a heterogeneidade do comportamento biológico das lesões odontogênicas epiteliais benignas e a escassez de estudos que tenham avaliado a expressão de proteínas de reparo do DNA nestas lesões, este trabalho avaliou a imunoexpressão de proteínas da via BER (APE-1 e XRCC-1) e NER (XPF) em ameloblastomas (AMEs) sólidos (n = 30), ceratocistos odontogênicos não sindrômicos (CONS) (n = 30), ceratocistos odontogênicos sindrômicos (COS) (associados à Síndrome de Gorlin) (n = 29), cistos dentígeros (CDs) (n = 30) e folículos dentários (FDs) (n = 20). A análise da expressão imunoistoquímica de APE-1, XRCC-1 e XPF foi realizada de forma quantitativa por um avaliador previamente calibrado e sem acesso aos dados clínicos dos casos. Em cinco campos de maior imunorreatividade, foram quantificadas as células positivas e negativas para as proteínas no componente epitelial de todos os casos, sendo estabelecido o percentual de células positivas em relação ao número total de células contadas para cada anticorpo. As marcações nucleares e citoplasmáticas foram analisadas separadamente para APE-1 e XPF, enquanto apenas a imunoexpressão nuclear foi considerada para XRCC-1. As comparações das medianas dos percentuais de imunorreatividade em relação aos grupos estudados foram realizadas por meio dos testes não paramétricos de Kruskal-Wallis e Mann-Whitney. Possíveis correlações entre a expressão de APE-1, XRCC-1 e XPF foram avaliadas por meio do teste de correlação de Spearman. O nível de significância foi estabelecido em 5% (p < 0,05). Foi verificada uma maior imunoexpressão nuclear de APE-1 nos CONSs, COSs e AMEs sólidos, em comparação com os CDs (p < 0,001). Dentre todos os grupos avaliados, a expressão citoplasmática de APE1 só foi encontrada em 4 CONSs e 6 COSs. A expressão nuclear de XRCC-1 foi estatisticamente maior nos CONSs e COSs em relação aos CDs (p < 0,05). Em nível nuclear, a expressão de XPF foi significativamente maior nos CONSs e COSs em relação aos CDs e AMEs (p < 0,05) e, embora sem significância estatística, foi observada uma maior expressão nuclear dessa proteína nos AMEs quando comparado aos CDs. Em relação à expressão citoplasmática de XPF, foi observada uma maior expressão nos COSs em relação aos CDs (p = 0,04). Nenhuma diferença estatisticamente significativa foi encontrada entre as expressões nucleares de APE-1, XRCC-1 e XPF entre CONSs e COSs (p > 0,05). Além disso, todas as lesões odontogênicas estudadas revelaram uma maior expressão estatisticamente significativa de APE-1 (nuclear), XRCC-1 (nuclear) e XPF (nuclear e citoplasmática) quando comparados aos FDs (p < 0,05). Para todas as lesões, o teste de correlação de Spearman mostrou uma correlação positiva entre a expressão nuclear de APE-1 e XRCC-1 ou XPF, em nível nuclear (p < 0,05). Os resultados deste estudo sugerem um potencial envolvimento das proteínas APE-1, XRCC-1 e XPF na patogênese das lesões odontogênicas epiteliais benignas, com destaque para aquelas com comportamento biológico mais agressivo (AU).

The benign epithelial odontogenic lesions present a heterogeneous biological behavior and their pathogenesis are not fully understood. The deoxyribonucleic acid (DNA) repair pathways act on specific types of damage to the genetic material, performing the repair and regulating several cellular processes. Among the main DNA repair pathways, the most notable are the base excision repair (BER) and the nucleotide excision repair (NER). Investigations have shown that the proteins involved in these pathways are deregulated and sometimes highly expressed in some malignancies, contributing to tumor progression. Taking into account the heterogeneity of the biological behavior of benign epithelial odontogenic lesions and the scarcity of studies that have evaluated the expression of DNA repair proteins in these lesions, this study evaluated the immunoexpression of BER (APE-1 and XRCC-1) proteins and NER (XPF) in solid ameloblastomas (AMEs) (n = 30), non-syndromic odontogenic keratocysts (NSOKCs) (n = 30), syndromic odontogenic keratocysts (SKOCs) (associated with Gorlin's Syndrome) (n = 29), dentigerous cysts (DCs) (n = 30) and dental follicles (DFs) (n = 20). The immunohistochemical analysis of APE-1, XRCC-1 and XPF was performed quantitatively by a previously calibrated evaluator and without access to the clinical data of the cases. In five fields of higher immunoreactivity, positive and negative cells were quantified for the proteins in the epithelial component of all cases, and the percentage of positive cells was established in relation to the total number of cells counted for each antibody. Nuclear and cytoplasmic markers were analyzed separately for APE-1 and XPF, while only nuclear immunoexpression was considered for XRCC-1. The comparisons of the median percentages of immunoreactivity in relation to the studied groups were performed using the non-parametric Kruskal-Wallis and MannWhitney tests. Possible correlations between the expression of APE-1, XRCC-1 and XPF were assessed by Spearman's correlation test. The level of significance was set at 5% (p < 0.05). A higher nuclear immunoexpression of APE-1 in the NSOKCs, SOKCs and solid AMEs was verified in comparison with the DCs (p < 0.001). Among all the evaluated groups, the cytoplasmic expression of APE-1 was only found in 4 NSOKCs and 6 SOKCs. Nuclear expression of XRCC-1 was statistically higher in NSOKCs and SOKCs than in DCs (p < 0.05). At the nuclear level, XPF expression was significantly higher in NSOKCs and SOKCs than in DCs and AMEs (p < 0.05) and, although without statistical significance, a higher nuclear expression of this protein was observed in AMEs when compared to CDs. Regarding the cytoplasmic expression of XPF, a greater expression was observed in the SOKCs in relation to the DCs (p = 0.04). No statistically significant difference was found between the nuclear expressions of APE-1, XRCC-1 and XPF between NSOKCs and SOKCs (p > 0.05). In addition, all the odontogenic lesions studied revealed a statistically significant expression of APE-1 (nuclear), XRCC-1 (nuclear) and XPF (nuclear and cytoplasmic) when compared to DFs (p < 0.05). For all lesions, Spearman's correlation test showed a positive correlation between nuclear expression of APE-1 and XRCC-1 or XPF at the nuclear level (p < 0.05). The results of this study suggest a potential involvement of APE-1, XRCC-1 and XPF proteins in the pathogenesis of benign epithelial odontogenic lesions. The role played by these proteins may be more important in odontogenic lesions with more aggressive biological behavior (AU).

Association of Base Excision Repair Gene Polymorphisms with the Response to Chemotherapy in Advanced Non-Small Cell Lung Cancer / 中华医学杂志(英文版)

Background@#Base excision repair (BER) plays an important role in the maintenance of genome integrity and anticancer drug resistance. This study aimed to explore the role of BER gene polymorphisms in response to chemotherapy for advanced non-small cell lung cancer (NSCLC) patients treated with platinum-based chemotherapy.@*Methods@#During the period from November 2009 to January 2016, a total of 152 patients diagnosed with NSCLC Stage IIIB and IV in the First Hospital of Jilin University were admitted into this study. The XRCC1 G28152A, MUTYH G972C, HOGG1 C1245G, and PARP1 T2444C polymorphisms of all the patients were detected by mass spectrometry. The logistic regression was used for statictical analysis. All tests were bilateral test, and a P < 0.05 was considered statistically significant.@*Results@#The logistic regression model showed that the response rate of chemotherapy of the PARP1 T2444C polymorphisms, CC genotype (odds ratio [OR]: 5.216, 95% confidence interval [CI]: 1.568-17.352, P = 0.007), TC genotype (OR: 2.692, 95% CI: 1.007-7.198, P = 0.048), as well as the genotype of TC together with CC (OR: 3.178, 95% CI: 1.229-8.219, P = 0.017) were significantly higher than those of TT wild type. There was no relationship between the MUTYH G972C, XRCC1 G28152A, and HOGG1 C1245G gene polymorphisms and chemosensitivity.@*Conclusions@#The PARP1 2444 mutation allele C might be associated with the decreased sensitivity to platinum-based chemotherapy in advanced NSCLC. These findings may be helpful in designing individualized cancer treatment.

Imunoexpressão das proteínas APE1, XRCC1, p53 e Ki67 em carcinoma de células escamosas de língua oral / Immunoexpression of APE1, XRCC1, p53 and Ki67 proteins in oral tongue squamous cell carcinoma

O carcinoma de células escamosas oral (CCEO) resulta de processos de descontroles de eventos celulares provocados por mutações decorrentes de agentes genotóxicos, o que pode levar, dentre outros fatores, à perda de controle do processo de proliferação celular, sendo este considerado um dos precursores do câncer oral. A busca por biomarcadores para o CCEO constitui alvo de várias pesquisas, dentre as quais destacam-se proteínas de reparo do DNA como a XRCC1 e APE1 e proteínas do ciclo celular como p53 e Ki67. Assim, o objetivo desta pesquisa foi analisar a expressão imunoistoquímica das proteínas de reparo APE1, XRCC1 e das proteínas envolvidas no ciclo celular p53 e ki67, associando-as entre si e com parâmetros prognósticos clínicos e histopatológicos, em carcinoma de células escamosas de língua oral (CCELO), visando contribuir para o melhor entendimento da participação dessas proteínas no desenvolvimento desta neoplasia. A expressão imunoistoquímica de APE1 e XRCC1 foi avaliada de forma semiquantitativa e a de p53 e ki67 de forma quantitativa, em 58 casos de Carcinoma de células escamosas de língua oral (CCELO). Os dados clínicos foram coletados nos prontuários médico de cada paciente e a gradação histopatológica de Brandwein-Gensler efetuada para cada caso. Para a análise estatística foram realizados os testes de Qui-quadrado e Exato de Fisher e adotou-se significância de p<0,05. A maioria dos casos apresentou alta imunoexpressão para APE1 (n = 36; 62,1%), assim como para XRCC1 (n = 38; 65,5%). Já para as proteínas Ki67 e p53, houve uma distribuição igual quando os casos foram categorizados em baixa e alta expressão (n = 29, 50%). A imunoexpressão de XRCC1 foi significativamente maior nos casos de lesão em estágio inicial I e II (n = 23; 62,2%) em relação aos estágios avançados III e IV (n=16, 80%, p = 0,05). A imunoexpressão de p53 foi significativamente maior nos casos de lesão em estágio avançado (n = 19; 65,5%) e baixa em estágios iniciais (n=17, 60,7%; p = 0,047). Nenhuma das proteínas estudadas mostrou associação entre si, nem com os demais parâmetros clínicos e a gradação histopatológica. Apesar da associação significativa da maior imunoexpressão de XRCC1 com melhor estadiamento clínico e da p53 com o pior estadiamento clínico, estas não foram embasadas quando analisado o desfecho dos pacientes. Os resultados desta pesquisa indicam que XRCC1 e APE1 participam do processo de carcinogênese do CCELO, porém, a expressão imunoistoquímica destas e de p53 e Ki67 não mostraram associação com parâmetros prognósticos (AU).

Oral squamous cells carcinoma (OSCC) results from processes of decontrol of cellular events caused by mutations due genotoxic agents, which may lead, among other factors, to loss of control of the cellular proliferation process, being considered as one of the precursors of oral cancer. Searching biomarkers for OSCC is the target of several studies, among the markers it is highlighted the DNA repair proteins, such as XRCC1 and APE1, and cell cycle proteins, such as p53 and Ki67. Thus, the aim of this study was to analyze the immunohistochemical expression of APE1, XRCC1 and the proteins involved in the cell cycle, p53 and ki67, associating them with clinical and histopathological prognostic parameters in oral tongue squamous cell carcinoma (OTSCC), in order to contribute to the better understanding of the participation of these proteins in the development of this neoplasia. The immunohistochemical expression of APE1 and XRCC1 was evaluated semiquantitatively and the expression of p53 and ki67 quantitatively, in 58 cases of OTSCC. Clinical data were collected from the medical records of each patient and the histopathological grading of Brandwein-Gensler was carried out for each case. For the statistical analysis, Chi-square and Fisher's exact test were performed, and significance was set at p <0.05. The majority of cases showed high immunoexpression of APE1 (n = 36; 62.1%), as well as of XRCC1 (n = 38; 65.5%). In relation to the Ki67 and p53 proteins, there was an equal distribution when the cases were categorized into low and high expression (n = 29, 50%). XRCC1 immunoexpression was significantly higher in cases of early stage lesions I and II (n = 23; 62.2%) compared to advanced stages III and IV (n = 16, 80%, p = 0.05). The Immunoexpression of p53 was significantly higher in cases of advanced lesion (n = 19; 65.5%) and low in early stages (n = 17, 60.7%, p = 0.047). None of the studied proteins showed association with each other, nor with the other clinical parameters and histopathological grading. Despite the significant association of the highest XRCC1 immunoexpression with better clinical staging and of p53 with the worst clinical staging, these results were not supported when the patients' outcome were analyzed. The results of this study indicate that XRCC1 and APE1 participate in the process of carcinogenesis of OTSCC, but the immunohistochemical expression of these proteins and also p53 and Ki67 did not show any association with prognostic parameters (AU).

X-ray repair cross-complementing group 1 Arg399Gln genetic polymorphism and risk of hepatocellular carcinoma in an Iranian population

Background: The association between X-ray repair cross-complementing group 1 [XRCC1] Arg399Gln gene polymorphism and hepatocellular carcinoma [HCC] has been investigated in several populations. However, the findings are controversial. The aim of this study was to address the association between XRCC1 Arg399Gln polymorphism and HCC in an Iranian population

Methods: We have evaluated the association between XRCC1 Arg399Gln gene polymorphism and HCC in 151 Iranian individuals [50 patients with HCC and 101 healthy matched controls] using polymerase chain reaction-restriction fragment length polymorphisms [PCR-RFLP] method

Results: Significant association was found for the XRCC1 A allele and HCC [OR = 1.93, 95% CI [1.16 - 3.25], P = 0.0099]. Also, genotype analysis by SNPStats online software showed a significant association between XRCC1 gene polymorphisms and HCC under co-dominant, dominant, and recessive genetic models

Conclusion: Our study provides evidence that the XRCC1 Arg399Gln polymorphism may be associated with the risk of HCC development in Iranian population

Associação da imunoexpressão das proteínas XRCC1, TFIIH E XPF com características clinicopatológicas e sobrevida em carcinoma epidermoide de língua oral / Association of immunoexpression of XRCC1, TFIIH and XPF proteins with clinicopathological characteristics and survival in oral tongue squamous cell carcinoma

Sistemas de reparo do DNA, genes e proteínas, são essenciais para manutenção da integridade do genoma, evitando graves doenças como o câncer. Desrregulação na expressão destas proteínas vem sendo associado tanto ao risco do desenvolvimento, como na evolução de variados cânceres humanos com destaque para o carcinoma epidermoide oral. O objetivo deste trabalho foi analisar a imunoexpressão das proteínas de reparo do DNA, XRCC1, THIIF e XPF em carcinoma epidermoide de língua oral (CELO) e investigar associação com parâmetros clínicos, histopatológicos, de desfecho e sobrevida em cinco anos. Setenta e quatro casos de CELO foram analisados por meio da técnica da imuno-histoquímica de forma semiquantitativa. Observou-se alta expressão das proteínas pesquisadas nas células parenquimatosas, identificando associação significativa da elevada expressão de XRCC1 com melhor estadiamento clínico (p=0,02). A regressão de Cox revelou tamanho do tumor (p<0,01), comprometimento linfonodal (p=0,04), estágio do tumor (p=0,02) e profundidade de invasão >4mm (p=0,05) como fatores prognósticos para CELO. Os resultados deste experimento sugerem que as proteínas XRCC1, TFIIH e XPF participam do processo de tumorigênese, entretanto a imunoexpressão das mesmas não pode ser utilizada como indicador independente de prognóstico para CELO (AU).

DNA repair systems, genes and proteins are essential for genome integrity maintenance, avoiding serious diseases such as cancer. Deregulation in the expression of those proteins has been associated with both the risk of development and evolution of various human cancers, including oral squamous cell carcinoma. The purpose of this study was to analyze the immunoreactivity of the DNA repair proteins XRCC1, THIIF and XPF in oral tongue squamous cell carcinoma (OTSCC) and to investigate its association with clinical and histopathological parameters, outcome and 5-year survival rate. Seventy-four cases of OTSCC were analyzed semi-quantitatively through immunohistochemistry. We observed that DNA repair proteins were highly expressed in parenchymal cells; however, we only observed a significant association between XRCC1 high expression and better clinical staging (p=0,02). Cox regression showed that tumor size (p<0,01), lymph node involvement (p=0,04), tumor stage (p=0,02) and depth of invasion> 4mm (p=0,05) were prognostic factors. The results of this experiment suggest that XRCC1, TFIIH and XPF participate in the tumorigenic process, however, their immunoexpression may not be used as an independent prognostic indicator for OTSCC (AU).

Association of XRCC1 genetic polymorphism with susceptibility to non-Hodgkin's lymphoma / 中国实验血液学杂志

The purpose of this study was to explore the association between X-ray repair cross-complementing group 1 (XRCC1)gene polymorphism and non-Hodgkin's lymphoma risk. A total of 282 non-Hodgkin's lymphoma (NHL) patients and 231 normal controls were used to investigate the effect of three XRCC1 gene polymorphisms (rs25487, rs25489, rs1799782) on susceptibility to non-Hodgkin's lymphoma. Genotyping was performed by using SNaPshot method. All statistical analyses were done with R software. Genotype and allele frequencies of XRCC1 were compared between the patients and controls by using the chi-square test. Crude and adjusted odd ratios and 95% confidence intervals were calculated by using logistic regression on the basis of genetic different models. For four kinds of NHL, subgroup analyses were also conducted. Combined genotype analyses of the three XRCC1 polymorphisms were also done by using logistic regression. The results showed that the variant genotype frequency was not significantly different between the controls and NHL or NHL subtype cases. Combined genotype analyses of XRCC1 399-280-194 results showed that the combined genotype was not associated with risk of NHL overall, but the VT-WT-WT combined genotype was associated with the decreased risk of T-NHL (OR: 0.21; 95%CI (0.06-0.8); P = 0.022), and the WT-VT-WT combined genotype was associated with the increased risk of FL(OR:15.23; 95%CI (1.69-137.39); P = 0.015). It is concluded that any studied polymorphism (rs25487, rs25489, rs1799782) alone was not shown to be rela-ted with the risk of NHL or each histologic subtype of NHL. The combined genotype with mutation of three SNP of XRCC1 was not related to the risk of NHL. However, further large-scale studies would be needed to confirm the association of decreased or increased risk for T-NHL and FL with the risk 3 combined SNP mutants of XRCC1 polymorphism.

Effects of polymorphisms in XRCC1 and APE1 on vinyl chloride-induced chromosome damage / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To evaluate the effects of polymorphisms in XRCC1 and APE1 genes on vinyl chloride (VC)-induced chromosomal damage in peripheral lymphocytes.</p><p><b>METHODS</b>In this study, 317 workers occupationally exposed to VC were recruited from a factory in Shandong Province, China. The micronucleus (MN) frequency in peripheral lymphocytes was used as an indicator of chromosomal damage. Polymerase chain reaction-restriction fragment length polymorphism and created restriction site combined with restriction fragment length polymorphism were used to determine the five single nucleotide polymorphisms in XRCC1 and APE1 genes in the base excision repair pathway. The association of chromosomal damage with these polymorphisms and the haplotype of XRCC1 was analyzed using Poisson regression and PHASE 2.0.2.</p><p><b>RESULTS</b>It was found that among the VC-exposed workers, individuals with XRCC1 polymorphisms (-77C/T, Arg194Trp, Arg280His, and Arg399Gln) had a significantly higher MN frequency than those with homozygous wild-type genotypes, with frequency ratios (FR) as follows, respectively: FR = 1.21, 95%CI: 1.05∼1.39 (P < 0.05); FR = 1.14, 95%CI: 1.00∼1.38 (P < 0.05); FR = 1.26, 95%CI: 1.11∼1.44 (P < 0.05); FR = 1.23, 95%CI: 1.08∼1.46 (P < 0.05). APE1 Asp148Glu was found of no significant relationship with MN frequency. Haplotype analysis of XRCC1 demonstrated that the MN frequencies in subjects with CTAA/CTAA and CCAA/CTAA were significantly higher than that in those with TCGG/TCGG (FR = 1.19, 95%CI: 1.02∼1.32, P < 0.05; FR = 1.41, 95%CI: 1.02∼1.87, P < 0.05). Furthermore, association was found between accumulated exposure to VC and XRCC1 polymorphisms (-77C/T, Arg194Trp, Arg280His, and Arg399Gln) after adjustment for age, sex, drinking, and smoking.</p><p><b>CONCLUSION</b>VC can induce chromosomal damage even when the exposure level is lower than the national occupational health standard of China (PC-TWA: 10 mg/m(3)); the polymorphisms in XRCC1 and APE1 are associated with chromosomal damage induced by VC.</p>

Role of PARP-1 in formaldehyde-induced DNA damage repair and apoptosis in human bronchial epithelial cells / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the role of poly (ADP-ribose) polymerase-l (PARP-1) in formaldehyde-induced DNA damage response in human bronchial epithelial (HBE) cells and to investigate the mechanism of formaldehyde carcinogenicity.</p><p><b>METHODS</b>The protein levels were measured by Western blot. The interaction between different proteins was determined by co-immunoprecipitation assay. The chemical inhibitor was used to confirm the relationship between PARP-1 and DNA damage repair.</p><p><b>RESULTS</b>After being exposed to different concentrations of formaldehyde for 4 h, HBE cells showed no significant changes in cell viability. Cell viability was significantly reduced after 24-h exposure to 80 and 160 µmol/L formaldehyde (P < 0.05). The 10 µmol/L formaldehyde resulted in significant increases in the protein levels of PARP-1 and XRCC-1. However, 80 µmol/L formaldehyde led to a significant decrease in the protein level of PARP-1 of 124 KD molecular weight but a significant increase in the protein level of PARP-1 of 89 KD molecular weight; there was no significant change in the protein level of XRCC-1. The co-immunoprecipitation assay showed that 10 µmol/L formaldehyde induced increased binding between PARP-1 and XRCC-1, but 80 µmol/L formaldehyde led to no significant change in binding between PARP-1 and XRCC-1. Here, we confirmed the role of 10 µmol/L formaldehyde in strand breaks by comet assay which showed an increase in the tail DNA content of HBE cells after 4-h formaldehyde exposure. No significant difference was observed in tail DNA content between treated HBE cells and control cells at 2 h after formaldehyde was removed. Moreover, compared with control, inhibition of PARP-1 induced a significant increase in tail DNA content, and a significant difference was observed in tail DNA content between inhibited HBE cells and control cells at 2 h after formaldehyde was removed. Inhibition of PARP-1 significantly reduced DNA repair capacity.</p><p><b>CONCLUSION</b>PARP-1 mediated the repair of DNA damage induced by low-concentration formaldehyde through recruiting XRCC-1 protein, and may be involved in the regulation of cell apoptosis induced by high-concentration formaldehyde.</p>

Study on laryngeal cancer related on polymorphism of the Arg399Gln of XRCC1 DNA repair gene in different nationalities in Xinjiang / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To study genetic polymorphism of XRCC1 Arg399Gln and the laryngeal cancer risk.@*METHOD@#A case-control study was performed on 60 patients with laryngeal squamous cell carcinoma and 120 random healthy control group. The two groups were matched by sex and age. Multiplex SNaPshot technic was used to explore polymorphism of DNA repair gene XRCC1 Arg399Gln in distribution of patient with laryngeal squamous cell carcinoma and normal control.@*RESULT@#The frequency of XRCC1c. 399Arg/Gln+Gln/Gln genotypes in the case group was higher than that in the control group (P Gln might lead to a increased risk of laryngeal cancer.

Relationship between single nucleotide polymorphisms and its haplotype of X-ray repair cross complementing group 1 and susceptibility of pancreatic carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>The aim of this study was to evaluate the effects of XRCCl gene polymorphisms and its haplotype on the susceptibility of pancreatic carcinoma.</p><p><b>METHODS</b>Peripheral blood DNA was extracted from 210 pancreatic carcinoma patients and 213 control subjects. SNaPshot technique was used for genotyping seven SNP sites of the XRCCl gene (rs3213403, rs25487, rs1799782, rs731420, rs1001581, rs12611088, and rs3213282). Logistic regression model was performed to analyze the relationship of different genotypes or haplotype and the susceptibility of pancreatic carcinoma.</p><p><b>RESULTS</b>The frequency for allele A at site rs25487 in the case group was significantly higher than that in the control group (P < 0.05). The frequency of GG, GA and AA genotype between the case group and control group had statistically significant differences (P < 0.05). Compared with GG genotype, the risk of pancreatic carcinoma in the subjects carrying mutated allele A (GA+AA) was increased by 0.648 times (P < 0.05). Among them the pancreatic carcinoma risk of individuals carrying A allele was increased by 0.552 times compared with the individuals carrying G allele. The frequency of allele and genotype at site rs1799782 in the case group and control group had a significant difference (P < 0.05). Compared with the CC genotype, the risk of pancreatic carcinoma in the subjects carrying mutated allele T (CT+TT) was increased by 0.683 times. Among them the pancreatic carcinoma risk of individuals carrying T allele was increased by 0.549 times compared with the individuals carrying C allele. Significant differences were observed in linkage disequilibrium between any two of the seven SNPs (P < 0.05), the frequency of H4-AGCCCGC, H6-GGCCCGG or H7-AGCCTAG haplotypes was significantly lower in the case group than that in the control group (P < 0.05).</p><p><b>CONCLUSIONS</b>The single nucleotide polymorphisms of rs25487 and rs1799782 for XRCC1 gene may be correlated with the occurrence of pancreatic carcinoma. The haplotypes of H4-AGCCCGC, H6-GGCCCGG and H7-AGCCTAG might be a potential genetic protective factor for the occurrence of pancreatic carcinoma.</p>

Correlation of single nucleotide polymorphisms of X-ray repair cross complementing group 1 gene to hereditary susceptibility of colorectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the correlation of single nucleotide polymorphisms (SNP) of XRCC1 gene to hereditary susceptibility of colorectal cancer.</p><p><b>METHODS</b>XRCC1 genotypes in 124 colorectal cancer patients and 214 matched healthy people as control were analyzed by SnaP Shot SNP-typing technique. Five different inheritance models including codominant, dominant, recessive, overdominant and log-additive were analyzed using logistic regression model. The haplotype distribution was estimated with phase and its correlation with the risk of colorectal cancer was evaluated.</p><p><b>RESULTS</b>The frequencies of mutant 25487G-A, 25489C-T and 1799782C-T alleles were 0.20, 0.11, 0.32 respectively in the patients, and 0.23, 0.13, 0.34 in the controls. There was no significant correlation of polymophisms of XRCC1 gene to the risk of colorectal cancer in 5 different inheritance models (P>0.05). GCT, GCC, ACC and GTC were the most common haplotypes and the odds ratios were 1, 1.35, 0.90 and 0.84 respectively. There was no significant difference of distribution between 2 groups in haplotypes.</p><p><b>CONCLUSION</b>Polymorphisms of XRCC1 gene, including rs25487, rs25489, rs1799782, are not associated with to the risk of colorectal cancer.</p>

The polymorphisms of XRCC1 gene and susceptibility to pulmonary cancer / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the relationship between the polymorphisms of DNA repair gene XRCC1 and susceptibility to pulmonary cancer.</p><p><b>METHODS</b>A case-control study of 209 lung cancer patients and 256 control subjects was conducted to investigate the role of XRCC1 gene in lung cancer. Genotyping was performed using PCR based restriction fragment length polymorphism (PCR-RFLP) technique.</p><p><b>RESULTS</b>The frequency (19.1%) of XRCC1-194 Trp/Trp in case group was significantly higher than that (10.9%) in control group (P < 0.05), OR for lung cancer was 2.215 (95% CI: 1.276-3.845). The frequency (6.7%) of XRCC1-280 His/His in case group was significantly higher than that (4.3%) in control group (P < 0.05), OR for lung cancer was 2.46 (95% CI: 1.141-5.304). There was no significant difference for XRCC1-399 Gln/Gln genotype between the two groups. Interaction analysis of gene polymorphisms and environment factors indicated that there was interactions between XRCC1-194 Trp/Trp and XRCC1-280 His/His genotypes and smoking. The risks of lung cancer in smokers with XRCC1-194 Arg/Trp+Trp/Trp and XRCC1-280 His/His+Arg/His were 4.889 (95% CI: 2.828-8.452) and 6.281(95% CI: 3.572-11.046), respectively.</p><p><b>CONCLUSION</b>These findings supported the hypothesis that the interaction of polymorphisms of XRCC1-194 Trp/Trp, XRCC1-280 His/His with smoking resulted in the increased risk of lung cancer, and the polymorphisms of XRCC and smoking could play an role in development of lung cancer.</p>

Polymorphism of XRCC1 and chromosome damage in workers occupationally exposed to benzene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the relationship between the polymorphisms of DNA repair gene (XRCC1 194, 280 and 399) and the chromosomal damage induced by benzene.</p><p><b>METHODS</b>The chromosomal damage of the peripheral lymphocytes in 459 workers occupationally exposed to benzene and 88 non-exposed controls were detected with cytokinesis-block micronucleus (CBMN) assay. PCR-RFLP technique was used to measure polymorphisms in XRCC1 194, 280 and 399.</p><p><b>RESULTS</b>It was found that the MN frequency (2.12‰ ± 1.88‰) of the exposed group was significantly higher than that (1.19‰ ± 1.68‰) of the control group (P < 0.05), in the exposed group, the MN frequency (3.00‰ ± 2.76‰) of older workers (> 35 years) was significantly higher than that (2.02‰ ± 1.71‰) of younger workers (≤ 35 years) (P < 0.05). The effect of genetic polymorphisms of XRCC1 on CBMN was not found. The haplotypes AAA/BAA, AAB/AAB, ABA/ABA, ABB/ABB could associated with the increased frequencies of total micronucleus (P < 0.05).</p><p><b>CONCLUSION</b>Benzene exposure could result in chromosome damage. Age of workers and diplotypes of XRCC1 could associated with chromosomal damage induced by benzene.</p>

Interaction between XRCC1 polymorphisms and intake of long-term stored rice in the risk of esophageal squamous cell carcinoma: a case-control study / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>This study aimed to explore the roles of three common single nucleotide polymorphisms in the X-ray repair cross-complementing group-1 gene (XRCC1) and of life style factors and their possible interactions in the risk of esophageal squamous cell carcinoma (ESCC) in China.</p><p><b>METHODS</b>A population-based case-control study of 432 cases and 915 controls was conducted in Yangzhong County, Jiangsu Province, China. Subjects were interviewed by trained interviewers using a structured questionnaire that included questions on demographics and life style. XRCC1 genotypes were analyzed using a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay. Unconditional logistic regression analysis was used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for associations of ESCC with XRCC1 polymorphisms and lifestyle-related factors.</p><p><b>RESULTS</b>Both the drinking of river water and alcohol intake history were significantly associated [SW1]with an increased risk of ESCC among men with aORs of 4.20 (95% CI: 2.90-6.07) and 2.03 (95% CI: 1.43-2.89), respectively. For women, the corresponding odds ratios were 8.37 (95% CI: 5.09-13.75) for river water drinking and 12.78 (95% CI: 2.69-60.69) for long-term stored rice intake. After the XRCC1 G28152A polymorphism was adjusted for potential confounders, subjects with GA and AA genotypes had an increased risk for ESCC (aOR: 1.21, 95% CI: 0.93-1.56), compared with subjects with a GG genotype, and a positive multiplicative interaction between intake of long-term stored rice and the XRCC1 G28152A polymorphism was observed (P=0.009).</p><p><b>CONCLUSIONS</b>Our findings suggest that both lifestyle-related factors, including drinking river water, long-term stored rice and alcohol intake, and the XRCC1 G28152A polymorphism were possible risk factors for ESCC, and that the XRCC1 G28152A polymorphism modified the effect of long-term stored rice intake on the risk of ESCC among Chinese people.</p>

Relationship between polymorphisms of X-ray repair cross-complementing group 1 gene Arg194Trp, Arg399Gln and susceptibility of breast cancer / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the relationship between two polymorphisms, Arg194Trp and Arg399Glu, of DNA repair gene X-ray repair cross-complementing group 1 (XRCC1) and the susceptibility of breast cancer in Chinese women.</p><p><b>METHODS</b>A case-control study with 698 histologically-confirmed female breast cancer cases and 813 cancer-free controls frequency-matched by age and residential area was conducted, and the genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. Logistic regression analysis was used to evaluate the odds ratios (ORs) and 95% confidence intervals (CIs) of XRCC1 Arg194Trp and Arg399Glu with susceptibility of breast cancer. A Meta-analysis was used to evaluate the association of Arg399Glu with breast cancer in Chinese women.</p><p><b>RESULTS</b>The genotype frequencies of Arg/Arg, Arg/Trp, Trp/Trp, Arg/Trp + Trp/Trp of XRCC1 gene 194 locus were 48.81% (327/670), 39.85% (267/670), 11.34% (76/670), 51.19% (343/670) in cases and 48.80% (387/793), 41.99% (333/793), 9.21% (73/793), 51.20% (406/793) in controls. Compared to Arg/Arg, the adjusted ORs (95%CIs) were 0.98 (0.75 - 1.28), 1.17 (0.76 - 1.80), 1.09 (0.86 - 1.40). The frequencies of Arg/Arg, Arg/Trp, Trp/Trp, Arg/Gln + Gln/Gln of XRCC1 399 locus were 52.40% (349/666), 38.29% (255/666), 9.31%(62/666), 47.60% (317/666) in cases and 52.22% (412/789), 38.53% (304/789), 9.25% (73/789), 47.78%(377/789) in controls. Compared to Arg/Arg, the adjusted ORs (95%CIs) were 0.93(0.63 - 1.08), 0.96 (0.42 - 1.09), 0.91 (0.62 - 1.05). No significant associations were found between these two polymorphisms and breast cancer risk, also in subgroups stratified by menopause status, history of breast-feed, reproduction and taking oral contraceptives. The overall ORs (95%CIs) of 399 Arg/Trp + Trp/Trp vs Arg/Arg from Meta analysis was 0.97 (0.85 - 1.10).</p><p><b>CONCLUSION</b>The XRCC1 Arg194Trp and Arg399Gln may not play an important role in the susceptibility of breast cancer in Chinese women.</p>

Association between genetic polymorphisms of ERCC1, XRCC1, GSTP1 and survival of advanced gastric cancer patients treated with oxaliplatin/5-Fu-based chemotherapy / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the association between the polymorphisms of excision repair cross complementation group 1 (ERCC1), X-ray repair cross complementing 1 (XRCC1), glutathione S-transferase Pi 1 (GSTP1) and the survival of advanced gastric cancer patients treated with oxaliplatin-based combination chemotherapy.</p><p><b>METHODS</b>Eighty five patients with advanced gastric cancer accepted oxaliplatin/5-FU-based chemotherapy as first-line chemotherapy were investigated. Peripheral venous blood was taken before chemotherapy. DNA was extracted from peripheral venous blood. The genetic polymorphisms were detected by real-time PCR assay. The association between time to progression, overall survival and the polymorphisms was analyzed.</p><p><b>RESULTS</b>The median time to progression of the 85 cases was 5.3 months, and the median overall survival was 8.0 months. ERCC1-118 C/C, XRCC1-399 G/G and GSTP1-105 A/G + G/G were favorable genotypes and the number of the favorable genotypes was associated with survival of the patients. The median overall survival was 12.5 months, 10.0 months, 6.5 months and 4.5 months for patients with 3 favorable genotypes, 2 favorable genotypes, 1 favorable genotype and none favorable genotype, respectively, with a significant difference (χ(2) = 35.54, P < 0.01).</p><p><b>CONCLUSION</b>Genetic polymorphisms of ERCC1-118, XRCC1-399 and GSTP1-105 are associated with TTP and OS of advanced gastric cancer patients treated with oxaliplatin/5-Fu-based combination chemotherapy as the first-line chemotherapy.</p>

hOGG1 Ser326Cys and XRCC1 Arg399Gln polymorphisms associated with chronic obstructive pulmonary disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cigarette-smoke induced DNA damage can cause airway cell apoptosis and death, which may be associated with the development of chronic obstructive pulmonary disease (COPD). However, only 20% - 30% of smokers develop COPD, suggesting that different degrees of DNA repair produce different outcomes in smokers, i.e., part of them develop COPD. We investigated the association between polymorphisms in DNA repair genes hOGG1 (Ser326Cys) and XRCC1 (Arg399Gln), alone or in combination, and susceptibility of COPD.</p><p><b>METHODS</b>Altogether 201 COPD patients and 309 controls were recruited and frequency-matched on age and sex. hOGG1 and XRCC1 genotypes were determined by PCR-restriction fragment length polymorphism analysis.</p><p><b>RESULTS</b>The risk of COPD was not significantly different among individuals with Ser/Cys and Cys/Cys genotypes compared with those with hOGG1 Ser/Ser genotype. The risk of COPD was not significantly different among individuals with Gln/Gln genotype compared with those with XRCC1 Arg/Arg genotype, but it was significantly elevated among individuals with Arg/Gln genotype (adjusted odds ratios (OR) = 1.55, 95% confidence intervals (CI) 1.05 - 2.29, P = 0.029). Assessment of smoking status in current smokers compared with those with hOGG1 Ser/Ser genotype revealed that the risk of COPD was significantly elevated among individuals with Cys/Cys genotype (adjusted OR = 5.07, 95% CI 1.84 - 13.95, P = 0.002). Compared with those with XRCC1 Arg/Arg genotype, the risk of COPD was significantly elevated among individuals with Arg/Gln genotype (adjusted OR = 2.77, 95% CI 1.52 - 5.07, P = 0.001). Assessment of smoking exposure in light smokers compared with those with hOGG1 Ser/Ser genotype showed that the risk of COPD was significantly elevated among individuals with Cys/Cys genotype (adjusted OR = 4.02, 95% CI 1.05 - 16.80, P = 0.042). Compared with those with XRCC1 Arg/Arg genotype, the risk of COPD was significantly elevated among individuals with Gln/Gln genotype (adjusted OR = 4.48, 95% CI 1.35 - 14.90, P = 0.014). In heavy smokers compared with those with XRCC1 Arg/Arg genotype, the risk of COPD was significantly elevated among individuals with Arg/Gln genotype (adjusted OR = 2.55, 95% CI 1.42 - 4.58, P = 0.002). When hOGG1 Ser326Cys and XRCC1 Arg399Gln polymorphisms were evaluated together, compared with those with 0 - 1 of hOGG1 326Cys and XRCC1 399Gln alleles, the risk of COPD was significantly elevated among individuals with 3 - 4 of hOGG1 326Cys and XRCC1 399Gln alleles (adjusted OR = 3.18, 95% CI 1.86 - 5.43, P = 0.000). Assessment of smoking status and smoking exposure in current/light/heavy smokers showed that the risk of COPD was significantly elevated among individuals with 3 - 4 of hOGG1 326Cys and XRCC1 399Gln alleles (adjusted OR = 8.32, 95% CI 3.59 - 19.27, P = 0.000; OR = 5.46, 95% CI 2.06 - 14.42, P = 0.001; OR = 2.93, 95% CI 1.43 - 6.02, P = 0.003; respectively).</p><p><b>CONCLUSIONS</b>hOGG1 Ser326Cys and XRCC1 Arg399Gln polymorphisms are associated with the susceptibility to COPD. The risk of COPD is significantly elevated among current/light smokers with hOGG1 326Cys and XRCC1 399Gln.</p>

E2F1 upregulates endogenous XRCC1 expression / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the regulatory effect and significance of transcription factor E2F1 on X-ray repair cross2 complementing 1 (XRCC1).</p><p><b>METHODS</b>Saos2 cells were transfected with the E2F1 expression vectors (tet-E2F1) and mutated E2F1 expression vectors (tet-132E). XRCC1 promotor luciferase reporter vector was constructed and transfected into Saos2 cells together with E2F1, E2F2, E2F3 and E2F4 expression vectors at different amount. The cells were collected 36 hours post-transfection for luciferase assays and absorbance was read at 570 nm.</p><p><b>RESULTS</b>Cotransfection of increasing amounts of E2F1 expression vector with the XRCC1 promoter-luciferase reporter caused a dose-dependent increase in luciferase activation. In contrast, DNA binding incompetent E2F1 (132E) could not activate the XRCC1 promoter-luciferase reporter.</p><p><b>CONCLUSION</b>E2F1 could upregulate endogenous XRCC1 expression and stimulate the XRCC1 promoter.</p>