8-hydroxy-2--deoxyguanosine and Carcinoma--Non-Small-Cell-Lung

The MIRCIT trial was a randomized, double-blind, placebo-controlled study of advanced Non-small cell lung cancer (NSCLC).. Patients were randomized to receive 10 mg or 20 mg of melatonin or placebo. Assessment of health-related quality of life (HRQoL) was completed at baseline, and at 2, 3 and 7 months. Survival and adverse events were collected. DNA damage marker 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) was measured during the first three months of chemotherapy.. Patients in the melatonin-treated group had better adjusted HRQoL scores, with a slightly significantly better score (2.69 points, 95% confidence interval (CI)=0.01-5.38, p=0.049) being found in social well-being. Median survival was 7.3 months (95% CI=3.42-11.14) without significant difference. A great amont of DNA damage marker was observed in the placebo-treated group, and this was associated with lower survival (r(2)=-0.656, p=0.02), implying the protective effect of melatonin in healthy cells.. Melatonin in combination with chemotherapy did not affect survival and adverse events of advanced patients with NSCLC, but there was a trend for better HRQoL.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Carcinoma, Non-Small-Cell Lung; Cisplatin; Deoxyguanosine; Disease-Free Survival; DNA Damage; Double-Blind Method; Female; Humans; Lung Neoplasms; Male; Melatonin; Middle Aged; Placebos; Quality of Life; Treatment Outcome

hOGG1 plays a role in several disease pathways, including various cancers. Despite such functional importance, how hOGG1 is regulated at the transcriptional level in human non-small cell lung cancer (NSCLC) remains unknown, particularly via DNA methylation changes. We obtained NSCLC tissues and adjacent non-cancerous tissues and examined hOGG1 mRNA expression levels. NSCLC cells were treated with 5-Aza to test whether DNA methylation can influence the expression of hOGG1. The MassARRAY EpiTYPER and luciferase reporter gene assays were used to define the functional region of the hOGG1 gene (including CpG sites). Finally, ChIP assay was utilized to verify transcription factor binding to the hOGG1 5'-UTR region. Our previous studies supported the idea that the methylation of the hOGG1 gene promoter region occurs frequently in NSCLC. Treatment with 5-Aza, a demethylating agent, led to a significant restoration of hOGG1 expression in NSCLC cell lines. Quantitative PCR and MassARRAY EpiTYPER assays demonstrated that methylation of the +322-327 CpG site in the 5'-UTR region of hOGG1 was higher in NSCLC tissues compared with adjacent non-cancerous tissues. Notably, the methylation level of +322-327 site (T/N) was inversely correlated with that of hOGG1 mRNA level (T/N) in 25 NSCLC tissues. ChIP assay and in silico prediction showed an association between the +322-327 CpG site and Sp1, which has been reported to be an activator of transcription. Importantly, luciferase reporter gene and ChIP assays showed that +322-327 CpG site methylation particularly reduced the recruitment of Sp1 to the 5'-UTR sequence in hOGG1 and reduced transcriptional activity ~50%. In summary, we have demonstrated that hOGG1 mRNA is downregulated in NSCLC tissues. Moreover, we identified that the methylated +322-327 CpG site in the hOGG1 5'-UTR is associated with reduced expression of hOGG1 by decreasing the recruitment of Sp1 to the 5'-UTR of hOGG1.

Topics: 5' Untranslated Regions; 8-Hydroxy-2'-Deoxyguanosine; Azacitidine; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Chromatin Immunoprecipitation; CpG Islands; Deoxyguanosine; DNA Glycosylases; DNA Methylation; Down-Regulation; Gene Expression Regulation, Neoplastic; Humans; Lung; Lung Neoplasms; Promoter Regions, Genetic; Real-Time Polymerase Chain Reaction; Sp1 Transcription Factor

Ribonucleoside-diphosphate reductase subunit M2, also known as ribonucleotide reductase small subunit, is an enzyme that in humans is encoded by the RRM2 gene and also Ribonucleoside-diphosphate reductase large subunit is an enzyme that in humans is encoded by the RRM1 gene. RRM1 is a gene important in determining tumor phenotype, but also induced the expression of PTEN tumor suppressor gene, cell migration, invasion and metastasis formation, and play a preventive role. ERCC2 DNA repair mechanism is associated in more than 20 genes involved in the NER pathway. The aim of this study is to investigate rs13181 ERCC2 (T>G) (Lys751Gln), rs12806698 RRM1 (-269C>A) and rs6759180 (located in the 5'UTR) RRM2 (10126436G>A) gene polymorphisms by using real time PCR technique in patients with NSCLC. 193 NSCLC cases and 141 healthy control cases were included in this study. A significant difference was found between rs12806698 RRM1 genotype distributions (*p: 0.034) and were determined increases the risk of disease approximately 3.044 times AA genotype having (*p: 0.014 OR: 3.044, 95%CI: 1.205-7,688). A significant difference was found between rs6759180 RRM2 genotype distributions (*p: 0.033) and were determined increases the risk of disease approximately 3.49 times GG genotype having (p: 0,009 OR: 3, 49, %95CI:1.291-9,482). It was found significant difference in serum 8-OHdG levels between patients and controls (*p: 0001).

Topics: 8-Hydroxy-2'-Deoxyguanosine; Alleles; Carcinoma, Non-Small-Cell Lung; Case-Control Studies; Deoxyguanosine; DNA Repair; Female; Gene Expression; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Lung Neoplasms; Male; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Ribonucleoside Diphosphate Reductase; Risk; Tumor Suppressor Proteins; Xeroderma Pigmentosum Group D Protein

Lung cancers in women, in nonsmokers, and in patients with adenocarcinoma from Asia have more prevalent mutations in the epidermal growth factor receptor (EGFR) gene than their counterparts. However, the etiology of EGFR mutations in this population remains unclear. The authors hypothesized that the human papillomavirus (HPV) type 16/18 (HPV16/18) E6 oncoprotein may contribute to EGFR mutations in Taiwanese patients with lung cancer.. One hundred fifty-one tumors from patients with lung cancer were enrolled to determine HPV16/18 E6 and EGFR mutations using immunohistochemistry and direct sequencing, respectively. Levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) in lung tumors and cells were evaluated using immunohistochemistry and liquid chromatography-mass spectrometry/mass spectrometry. An supF mutagenesis assay was used to determine H2 O2 -induced mutation rates of lung cancer cells with or without E6 expression.. Patients with E6-positive tumors had a greater frequency of EGFR mutations than those with E6-negative tumors (41% vs 20%; P = .006). Levels of 8-oxo-dG were correlated with EGFR mutations (36% vs 16%; P = .012). Two stable clones of E6-overexpressing H157 and CL-3 cells were established for the supF mutagenesis assay. The data indicated that the cells with high E6 overexpression had higher H2 O2 -induced SupF gene mutation rates compared with the cells that expressed lower levels of E6 and compared with vector control cells.. HPV16/18 E6 may contribute in part to EGFR mutations in lung cancer, at least in the Taiwanese population.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Carcinoma, Non-Small-Cell Lung; Deoxyguanosine; DNA-Binding Proteins; ErbB Receptors; Female; Humans; Lung Neoplasms; Male; Mutagenesis; Mutation; Oncogene Proteins, Viral; Reactive Oxygen Species; Repressor Proteins; Transfection

The present investigation was taken up to evaluate the 8-oxo-7,8-dihydro-2'-deoxyguanosine and malondialdehyde as markers of oxidative stress, the levels of antioxidants and the correlations between these oxidative stress markers and antioxidants in lung cancer patients.. The study included 222 patients (158 men and 64 women, age ranging from 32 to 85 years) and 207 control subjects (153 men and 54 women, aged 30-80 years) for the analysis of urinary excretion of 8-oxodG using an ELISA assay, plasma malondialdehyde using spectrophotometer and red cell Cu-Zn SOD and GPx activities by kit methods.. The levels of 8-oxodG and malondialdehyde were significantly higher (p < 0.001) and red cell superoxide dismutase and glutathione peroxidase activities (p < 0.001) were significantly lower in lung cancer patients than in controls. There was a significantly positive correlation between 8-oxodG and malondialdehyde (r=0.912, p < 0.001) and a negative correlation between 8-oxodG and antioxidants.. Our results demonstrate that an increased rate of oxidative stress might play a role in the pathogenesis of lung cancer as evidenced by a failure in the oxidant/antioxidant balance in favour of lipid peroxidation and DNA damage.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Antioxidants; Biomarkers; Carcinoma, Non-Small-Cell Lung; Deoxyguanosine; Humans; Lung Neoplasms; Malondialdehyde; Oxidative Stress

This study was aimed at defining the reference ranges for biomarkers of oxidized guanine in (2'-deoxy)ribonucleotides and nucleic acids from a large Italian sample. We recruited 300 healthy subjects (150 males; mean age 44.1±13.6years; 26% smokers) without any known exposure to occupational oxidizing agents. They were asked to provide a spot urine sample, on which the following markers were determined by liquid chromatography-tandem mass spectrometry: 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), 8-oxo-7,8-dihydroguanosine (8-oxoGuo), 8-oxo-7,8-dihydroguanine (8-oxoGua), and cotinine. The reference ranges, estimated as the 5th-95th percentiles of creatinine-normalized values (pmol/μmol(creat)) were 0.7-4.2, 0.9-4.7, and 5.6-120.7 for 8-oxodGuo, 8-oxoGuo, and 8-oxoGua, respectively. Oxidation biomarkers were correlated with one another (p<0.005) and with urinary creatinine (p<0.0001). Males excreted significantly higher concentrations of 8-oxoGua than females (p<0.0001). 8-OxoGua and 8-oxoGuo showed a positive association with age (p<0.001), also after stratification by gender. Multiple linear regression models including urinary creatinine concentration, age, and smoking habit as independent variables showed a significant effect of age, but not of smoking, on the levels of 8-oxoGuo in males (p<0.0001) and of both 8-oxoGuo and 8-oxoGua in females (p<0.0001). A preliminary assessment in a small group (n=25) of patients affected by advanced non-small-cell lung cancer and receiving platinum-based chemotherapy showed significantly higher values of both 8-oxoGuo and 8-oxodGuo (p<0.0001 for both) compared to the referent population.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Age Factors; Aged; Aged, 80 and over; Biomarkers; Carcinoma, Non-Small-Cell Lung; Chromatography, Liquid; Cotinine; Deoxyguanosine; Female; Guanine; Guanosine; Humans; Lung Neoplasms; Male; Middle Aged; Nucleic Acids; Oxidation-Reduction; Oxygen; Reference Values; Smoking; Tandem Mass Spectrometry; Young Adult

Decreased repair of oxidative DNA damage is a risk factor for developing certain human malignancies. We have previously found that the capacity of 8-oxo-7,8-dihydroguanine repair was lower in leukocytes of NSCLC patients than in controls. To explain these observations, we searched for mutations and polymorphisms in the OGG1 gene among 88 NSCLC patients and 79 controls. One patient exhibited a heterozygous mutation in exon 1, which resulted in Arg46Gln substitution. Normal lung and tumor tissue carrying this mutation showed markedly lower 8-oxoG incision activity than the mean for all patients. The predominant polymorphism of OGG1 was Ser326Cys. A significant difference was observed in the frequencies of the OGG1 variants between populations of NSCLC patients and controls. The frequency of the Cys326 allele and the number of Cys326Cys homozygotes was higher among patients than controls. In individuals with either Ser326Cys or Cys326Cys genotype 8-oxoG incision rate was lower than in those with both Ser326 alleles, either in lung or leukocytes. Moreover, 8-oxodG level was higher in lung tissue and leukocytes of patients carrying two Cys326 alleles and in leukocytes of patients with the Ser326Cys genotype. We also screened for polymorphisms of the XRCC1 gene. Only heterozygotes of the XRCC1 variants Arg194Trp, Arg280His and Arg399Gln were found among patients and controls, with the frequency of Arg280His being significantly higher among patients. NSCLC patients with Arg280His or Arg399Gln polymorphism revealed lower 8-oxoG incision activity in their lung tissues, but not in leukocytes. We can conclude that the OGG1 Ser326Cys polymorphisms may have an impact on the efficiency of 8-oxoG incision in humans and the XRCC1 His280 and Gln399 may influence the OGG1 activity in tissues exposed to chronic oxidative/inflammatory stress. Higher frequency of the OGG1 Cys326 allele among NSCLC patients may partially explain the impairment of the 8-oxoG repair observed in their leukocytes.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Carcinoma, Non-Small-Cell Lung; Case-Control Studies; Deoxyguanosine; DNA Repair; DNA-Binding Proteins; Female; Guanine; Humans; Leukocytes; Lung; Lung Neoplasms; Male; Middle Aged; Polymorphism, Genetic; X-ray Repair Cross Complementing Protein 1

Cigarette smoke is strongly associated with NSCLC, but the carcinogenesis of NSCLC is poorly understood.. To discover the role of oxidative stress and anti-oxidative defense in NSCLC, we measured NADPH oxidase (NOX) activity, myeloperoxidase activity, 8-OHdG, and glutathione content from lung specimens. These came from 32 patients: 22 NSCLC patients and ten controls without cancer.. In NSCLC patients, NOX activity was significantly higher both in the malignant (p = 0.001) and non-malignant (p = 0.044) samples from NSCLC patients, than in the control specimens. Myeloperoxidase activity was lower (p = 0.001) and glutathione content (p = 0.009) higher in malignant tissue. No significant difference was observable in 8-OHdG content between patient groups.. Increase in NOX activity in the malignant tissues was independent of smoking history and myeloperoxidase activity, suggesting its independent role in NSCLC pathogenesis.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Adolescent; Adult; Aged; Aged, 80 and over; Antioxidants; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Case-Control Studies; Deoxyguanosine; Female; Glutathione; Humans; Lung Neoplasms; Male; Middle Aged; NADPH Oxidases; Oxidative Stress; Peroxidase; Smoking; Young Adult

The decrease in the copy number of mitochondrial DNA (mtDNA) in cancer tissues might be associated with a decrease in oxidative mtDNA damage to achieve cancer immortalization and progression. Lung cancer specimens were collected from 29 patients with stage III non-small cell lung cancer (NSCLC) after neoadjuvant chemotherapy followed by surgical resection. The relative mtDNA copy number and the oxidative mtDNA damage (formation of 8-OHdG in mtDNA) of each cancer tissue were measured by quantitative real-time PCR. Seven female and 22 male lung cancer patients, with a mean age of 63.5 years were evaluated. Tumors of five patients became progressive, 13 stable, and 11 partially responsive after preoperative chemotherapy. Low mtDNA copy number (P=0.089) and low degree of oxidative mtDNA damage (P=0.036) were found to associate with tumor progression. Moreover, mtDNA copy number was significantly related to the degree of oxidative mtDNA damage (P=0.031). The mtDNA copy number and oxidative mtDNA damage were lower in advanced NSCLC after chemotherapy. This finding suggests that a decrease in the content of mtDNA may result in a decrease of mitochondrial density in cancer cells, which leads to a decrease of endogenous ROS production and reduction of ROS-triggered DNA damage to achieve immortalization.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Chemotherapy, Adjuvant; Cisplatin; Deoxycytidine; Deoxyguanosine; Disease Progression; DNA Damage; DNA, Mitochondrial; Down-Regulation; Female; Gemcitabine; Gene Expression Regulation, Neoplastic; Humans; Lung Neoplasms; Male; Middle Aged; Neoadjuvant Therapy; Oxidative Stress; Pneumonectomy; Retrospective Studies; Treatment Outcome

8-Hydroxy-2'-deoxyguanosine (8-OH-dG) is 1 of the most abundant oxidative products of cellular DNA. Accumulation of impaired 8-OH-dG could lead to increased genomic instability that in turn could lead to a more malignant phenotypic behavior of tumors. Therefore, the effects of 8-OH-dG on survival in 99 resected nonsmall-cell lung cancer (NSCLC) patients was evaluated.. The enzyme-linked immunosorbent assay was applied to measure the levels of 8-OH-dG in tumor DNA. The median levels of 8-OH-dG were 6.5 pmol/microg for all study subjects.. Patients with low levels of 8-OH-dG had significantly longer survival times compared with those with high levels of 8-OH-dG (log-rank test: P < .001). In Cox regression analysis, patients with high levels of 8-OH-dG had an over 3-fold increased hazard of death. In addition, a statistically significant correlation between levels of 8-OH-dG and age was noted (rho = 0.206, P = .048). Furthermore, we observed a genotype-phenotype modification between hOGG1 gene polymorphism (Ser326Cys) and levels of 8-OH-dG.. The results demonstrated that levels of 8-OH-dG could predict survival in resected NSCLC patients. It is postulated that an intact base excision repair mechanism may reduce the accumulation of oxidative DNA damage that is thought to contribute to the tumor's malignant potential and therefore the risk of death.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Biomarkers, Tumor; Carcinoma, Non-Small-Cell Lung; Deoxyguanosine; DNA Damage; DNA Glycosylases; DNA Repair; DNA, Neoplasm; Enzyme-Linked Immunosorbent Assay; Female; Genotype; Humans; Lung Neoplasms; Male; Middle Aged; Polymorphism, Genetic; Retrospective Studies; Survival Rate