8-hydroxy-2--deoxyguanosine and Lung-Neoplasms

Manufacturers have developed prototype cigarettes yielding reduced levels of some tobacco smoke toxicants, when tested using laboratory machine smoking under standardised conditions. For the scientific assessment of modified risk tobacco products, tests that offer objective, reproducible data, which can be obtained in a much shorter time than the requirements of conventional epidemiology are needed. In this review, we consider whether biomarkers of biological effect related to oxidative stress can be used in this role. Based on published data, urinary 8-oxo-7,8-dihydro-2-deoxyguanosine, thymidine glycol, F2-isoprostanes, serum dehydroascorbic acid to ascorbic acid ratio and carotenoid concentrations show promise, while 4-hydroxynonenal requires further qualification.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Ascorbic Acid; Biomarkers; Carotenoids; Dehydroascorbic Acid; Deoxyguanosine; F2-Isoprostanes; Humans; Lung Neoplasms; Oxidative Stress; Risk; Smoking; Thymidine; Tobacco Products; Tobacco Smoke Pollution

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

To assess oxidative damage to DNA during lung cancer (LC) treatments.. Urinary levels of 8-oxoguanine (8-oxoGua) and levels of 8-oxo-2'-deoxyguanosine (8-oxodG) from urine and whole blood were determined in 36 non-cancer controls and 65 LC patients before any treatments. Samples were also obtained of LC patients during and after radiotherapy (RT, n=33) and chemotherapy (CT, n=16).. Stage IV LC patients had higher urinary 8-oxoGua and 8-oxodG levels than patients with stage I-III disease (p=0.044 and p=0.034, respectively). Urinary 8-oxodG levels increased during the first week of RT (p<0.001). Nuclear 8-oxodG increased during RT and 3 months after start of RT. Nuclear 8-oxodG levels also rose between the first two CT cycles (p=0.043), and urinary 8-oxodG levels during the sixth CT cycle (p=0.009).. Urinary DNA damage biomarker levels may be associated with LC stage. Both RT and CT increase the parameters of DNA oxidation.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Aged, 80 and over; Biomarkers, Tumor; Demography; Deoxyguanosine; DNA Damage; Female; Guanine; Humans; Lung Neoplasms; Male; Middle Aged; Oxidative Stress; Survival Analysis; Treatment Outcome

Ratios of urinary 8-hydroxy-2'-deoxyguanosine to urinary creatinine (8-OHdG/creatinine) have been considered as a good biological indicator of DNA oxidation. Urinary 8-OHdG/creatinine levels of lung cancer patients were evaluated by enzyme-linked immunosorbent assay using a monoclonal antibody N45.1 during radiotherapy and chemotherapy. An increase in urinary 8-OHdG/creatinine was found in non-small-cell carcinoma (non-SCC) patients during the course of radiotherapy. SCC patients showed higher levels of urinary 8-OHdG/creatinine than the controls. Furthermore, SCC patients with complete or partial response to the chemotherapy showed a significant decrease in urinary 8-OHdG/creatinine while patients with no change or progressive disease showed an increase.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Biomarkers; Carcinoma, Small Cell; Creatinine; Cross-Sectional Studies; Deoxyguanosine; DNA; Female; Humans; Lung Neoplasms; Male; Middle Aged; Oxidation-Reduction; Smoking; Treatment Outcome

Hexavalent chromium [Cr(VI)] is an occupational carcinogen that accumulates in the lungs and causes lung injury and even lung cancer. 36 SD male rats received inhalable intratracheal instillation of Cr(VI) (0.05, 0.25 mg Cr/kg) or the same volume (3 ml/kg) of normal saline weekly for 28 days (total 5 times). After 28 days of exposure, half of the rats in each group were sacrificed for investigation, and the rest stopped exposure and began to be self-repaired for two weeks. Histopathology analyses revealed that Cr(VI) induced slight dilatation and hemorrhage of perialveolar capillaries, pulmonary bronchodilation, and congestion with peripheral flaky-like necrosis accompanied by inflammatory cell infiltration, especially the 0.25 mg Cr/kg group. Cr(VI) exposure caused the increase of blood Cr, urinary Cr, MDA, urinary 8-hydroxy-2' -deoxyguanosine (8-OHdG), and the decrease of GSH and MDA, while two-week repair only reduced urinary Cr. Exposure to Cr(VI) significantly upregulated FOXO1 and downregulated p-AKT and p-FOXO1 for two weeks. PI3K in the 0.25 mg Cr/kg group was inhibited after two weeks of repair. Cr(VI) exposure mainly promoted GADD45a and CHK2 in the exposure group, promoted Bim, Bax/Bcl-2, and suppressed Bcl-2 and Bcl-xL in the repair group. These results demonstrate that Cr(VI) may induce DNA damage repair and apoptosis in the lung by activating the PI3K/AKT/FOXO1 pathway. Two-week repair may alleviate oxidative stress and DNA damage induced by Cr(VI) exposure but couldn't eliminate its effects. This study provides a new perspective for exploring the Cr(VI) induced lung cancer mechanism.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Apoptosis; Chromium; DNA Damage; Lung; Lung Neoplasms; Male; Oxidative Stress; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Rats

Osteosarcoma (OS) is the most common primary malignant bone tumour. Unfortunately, no new treatments are approved and over the last 30 years the survival rate remains only 30% at 5 years for poor responders justifying an urgent need of new therapies. The Mutt homolog 1 (MTH1) enzyme prevents incorporation of oxidized nucleotides into DNA and recently developed MTH1 inhibitors may offer therapeutic potential as MTH1 is overexpressed in various cancers.. The aim of this study was to evaluate the therapeutic benefits of targeting MTH1 with two chemical inhibitors, TH588 and TH1579 on human osteosarcoma cells. Preclinical efficacy of TH1579 was assessed in human osteosarcoma xenograft model on tumour growth and development of pulmonary metastases.. MTH1 is overexpressed in OS patients and tumour cell lines, compared to mesenchymal stem cells. In vitro, chemical inhibition of MTH1 by TH588 and TH1579 decreases OS cells viability, impairs their cell cycle and increases apoptosis in OS cells. TH1579 was confirmed to bind MTH1 by CETSA in OS model. Moreover, 90 mg/kg of TH1579 reduces in vivo tumour growth by 80.5% compared to non-treated group at day 48. This result was associated with the increase in 8-oxo-dG integration into tumour cells DNA and the increase of apoptosis. Additionally, TH1579 also reduces the number of pulmonary metastases.. All these results strongly provide a pre-clinical proof-of-principle that TH1579 could be a therapeutic option for patients with osteosarcoma.. This study was supported by La Ligue Contre le Cancer, la SFCE and Enfants Cancers Santé.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antineoplastic Agents; Apoptosis; Bone Neoplasms; Cell Line, Tumor; DNA; DNA Repair Enzymes; Humans; Lung Neoplasms; Mice; Osteosarcoma; Phosphoric Monoester Hydrolases; Pyrimidines; Tumor Cells, Cultured

Oxidative stress has been linked to cancer development in previous studies. However, the association between pre-diagnostic oxidatively generated DNA/RNA damage levels and incident cancer has rarely been investigated. Urinary oxidized guanine/guanosine (OxGua) concentrations, including 8-hydroxy-2'-deoxyguanosine, were assessed in 8,793 older adults in a population-based German cohort. 1,540 incident cancer cases, including 207 lung, 196 colorectal, 218 breast and 245 prostate cancer cases were diagnosed during over 14 years of follow-up. Associations of OxGua levels with cancer outcomes were not observed in the total population in multi-variable adjusted Cox regression models. However, in subgroup analyses, colorectal cancer incidence increased by 8%, 9% and 8% with one standard deviation increase in OxGua levels among current non-smokers, female and non-obese participants, respectively. Additionally, among non-smokers, overall and prostate cancer incidences statistically significantly increased by 5% and 13% per 1 standard deviation increase in OxGua levels, respectively. In contrast, OxGua levels were inversely associated with the risk of prostate cancer among current smokers. However, none of the subgroup analyses had p-values below a threshold for statistical significance after correction for multiple testing. Thus, results need to be validated in further studies. There might be a pattern that oxidatively generated DNA/RNA damage is a weak cancer risk factor in the absence of other strong risk factors, such as smoking, obesity and male sex.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Aged, 80 and over; Breast Neoplasms; Colorectal Neoplasms; DNA Damage; Female; Follow-Up Studies; Humans; Incidence; Lung Neoplasms; Male; Middle Aged; Obesity; Oxidative Stress; Prostatic Neoplasms; Risk Factors; Sex Factors; Smoking

The current systemic treatments of the various solid tumors involve Cisplatin (CIS)-based chemotherapy. Due to its cytotoxicity, this approach is limited. Moreover, the safety of CIS is only discussed especially in breast and stomach cancers. Therefore, we, for the first time, explored the restorative efficacy of oleuropein (OLE), in stomach and lung injuries induced by CIS. Sprague-Dawley rats were divided into eight groups: control CIS, OLE and CIS + OLE. Single dose of (7 mg/kg) CIS was administered intraperitoneally to CIS and CIS + OLE groups. After 24 h, 50, 100 and 200 mg/kg OLE was given for three consecutive days to OLE and CIS + OLE groups. The 8-OH-dG, total oxidative/antioxidant status (TOS/TAS) and malondialdehyde (MDA) levels were evaluated and histopathological analyses were performed on the studied tissues. The results indicated that CIS significantly increased 8-OH-dG, MDA and TOS levels and caused severe tissue damages. However, high dose of OLE induced a significant decrease in the 8-OH-dG, MDA levels, an increase in TAS levels and it restores CIS-induced tissue damages. We hope that the results of this study will provide an impetus for future studies on novel therapeutic strategies including the protective use of oleuropein in gastric and lung cancers due to chemotherapy.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antioxidants; Cisplatin; Deoxyguanosine; DNA Damage; Iridoid Glucosides; Iridoids; Lung Neoplasms; Male; Malondialdehyde; Molecular Structure; Oxidative Stress; Rats; Rats, Sprague-Dawley; Stomach Neoplasms

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

8-hydroxydeoxyguanosine (8-OHdG) is generated consequent to oxidative stress, but its paradoxical anti-oxidative, anti-inflammatory, and anti-mutagenic effects via Rho-GTPase inhibition were noted in various models of inflammation and cancer. Metastasis occurs through cell detachment, epithelial-mesenchymal transition (EMT), and cell migration; during these processes, changes in cell morphology are initiated through Rho-GTPase-dependent actin cytoskeleton polymerization. In this study, we explored the anti-metastatic mechanisms of 8-OHdG in Panc-1 pancreatic cancer cells. 8-OHdG inhibits cell migration by inactivating ERM and Rho-GTPase proteins, and inhibiting focal adhesion kinase (FAK) and matrix metalloproteinases (MMPs). At 15min, 8-OHdG significantly inactivated ERM (p < 0.05) and led to a significant retardation of wound healing; siERM and H1152 (ROCK inhibitor) had similar effects (p < 0.05). However, FAK inhibitor 14, DPI (NOX inhibitor), and NAC (antioxidant) significantly delayed wound healing without inhibiting ERM or CD44 (p < 0.05). In the experiments on cell migration, siERM, siCD44, DPI, and 8-OHdG significantly inhibited MMPs. 8-OHdG significantly decreased DCF-DA activation in Panc-1 pancreatic cancer cells and down-regulated NOXs (nox-1, nox-2, and nox-3). Finally, all of these anti-migration actions of 8-OHdG resulted in significant inhibition of EMT, as evidenced by the up-regulation of ZO-1 and claudin-1 and down-regulation of vimentin. We found significant inhibition of lung metastasis of Panc-1 cells by 8-OHdG. In conclusion, exogenous 8-OHdG had potent anti-metastasis effects mediated by either ERM or Rho GTPase inhibition in metastasis-prone pancreatic cancer cells.

Topics: 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; 8-Hydroxy-2'-Deoxyguanosine; Acetylcysteine; Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Movement; Claudin-1; Deoxyguanosine; DNA-Binding Proteins; Epithelial-Mesenchymal Transition; Focal Adhesion Kinase 1; Gene Expression Regulation, Neoplastic; GTPase-Activating Proteins; Humans; Hyaluronan Receptors; Imidazoles; Lung Neoplasms; Matrix Metalloproteinases; Mice; Mice, Nude; NADPH Oxidases; Pancreatic Neoplasms; Pyrroles; rho-Associated Kinases; Signal Transduction; Transcription Factors; Vimentin; Xenograft Model Antitumor Assays; Zonula Occludens-1 Protein

Oxidative damage is a major contributing factor to carcinogenesis and obstructive disorders in lungs. Current evidence suggests that the inflammatory processes yield to oxidative mechanisms, which underlie COPD, lung cancer, and obstructive sleep apnea syndrome (OSAS). This study aimed to evaluate the oxidative damage in these diseases by evaluating the oxidative and antioxidant biomarkers.. Malondialdehyde, 8-oxo-7,8-dihydro-2'-deoxyguanosine, and coenzyme Q10 levels were evaluated in the blood samples of subjects with COPD, lung cancer, and OSAS by high-pressure liquid chromatography.. A total of 111 participants (35 females, 76 males) with OSAS (n = 29), COPD (n = 26), and lung cancer (n = 28) and healthy controls (n = 28) were included in the study. The malondialdehyde and coenzyme Q10 levels were significantly higher in all 3 diseases when compared with controls (P < .01), whereas 8-oxo-7,8-dihydro-2'-deoxyguanosine levels were only significantly higher than in healthy controls in subjects with lung cancer (P = .005). The highest levels of malondialdehyde and coenzyme Q10 were determined in subjects with OSAS and lung cancer, respectively. The highest 8-oxo-7,8-dihydro-2'-deoxyguanosine levels were also observed in subjects with lung cancer, but the differences of this biomarker with other diagnoses were not statistically significant (P = .56).. Oxidative damage was observed in all 3 diagnoses, and, as a response to oxidative stress, antioxidant mechanisms were also active in these diseases. Malondialdehyde and 8-oxo-7,8-dihydro-2'-deoxyguanosine were found to be efficiently usable in the evaluation of oxidative damage in chronic respiratory diseases. (ClinicalTrials.gov registration NCT02406053.).

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Antioxidants; Biomarkers; Case-Control Studies; Deoxyguanosine; Female; Humans; Lung Neoplasms; Male; Malondialdehyde; Middle Aged; Oxidative Stress; Prospective Studies; Pulmonary Disease, Chronic Obstructive; Sleep Apnea, Obstructive; Ubiquinone

Indoor air pollution induces asthma, leads to chronic obstructive pulmonary disease, and may promote lung cancer. Our previous studies found that the accumulation of inorganic particulate matter that is due to indoor air pollution can lead to damage to alveolar cells and activation of signaling pathway, and ultimately provoke tumorigenesis. The aim of this study is to explore the accumulation of inorganics and activation of nuclear factor κB (NF-κB)-inducible nitric oxide synthase (iNOS) signaling pathway of lung tissue in Xuanwei lung cancer patients.. From December 2013 to November 2014, 48 cases Xuanwei patients with lung cancer who underwent surgical treatment from the Third Affiliated Hospital of Kunming Medical University were enrolled in this study and compared with lung cancer patients from other regions. The ultrastructure of postoperative specimens was observed by transmission electron microscopy (TEM) to explore the occurrence of inorganic particles. Serum cytokines were analyzed. Then, the expression levels of NF-κB-p65 protein and iNOS protein in postoperative specimens was explored by immunohistochemistry and Western blot. Finally, 8-OHdG accumulation in lung cancer tissues and urine was measured.. A large number of nanoscale inorganics were observed in alveolar type II cells and macrophages located in adjacent tissues of lung cancer with Xuanwei patients. Silicon (Si) content was found in inorganic elemental analysis. The serum interleukin (IL)-1β levels (31.50 ± 19.16) pg/mL of Xuanwei lung-cancer patients were remarkably higher than those from other regions (11.33 ± 6.94) pg/mL (P<0.01), with statistically significant difference. The pathological tissues of Xuanwei lung-cancer patients express NF-κB-p65, and iNOS expression were significantly higher than those of patients from non-Xuanwei regions. No significant difference was found between cancerous and normal adjacent tissues. Xuanwei lung-cancer tissues and urine 8-OHdG level (40.124 ± 8.597) ng/mgCr were significantly higher than those of patients from other regions (25.673 ± 7.986) ng/mg Cr (P<0.05), with statistically significant difference.. The accumulation of inorganics and the activation of NF-κB-iNOS signaling pathway may contribute to Xuanwei lung cancer.
.. 背景与目的 室内空气污染不仅会诱发哮喘，也会导致慢性阻塞性肺疾病（chronic obstructive pulmonary disease, COPD），甚至促进肺癌发生。随着宣威肺癌的病因学研究，发现室内空气污染最终造成肺部无机颗粒物的沉积，这些物质可以造成肺泡细胞损伤、信号通路激活，最终促进肿瘤的发生。本研究旨在探讨宣威肺癌患者肺部中无机杂质的赋存以及核转录因子（nuclear factor κB, NF-κB）-诱导型一氧化氮合成酶（inducible nitric oxide synthase, iNOS）信号通路的激活情况。方法 选取48例2013年12月-2014年11月在昆明医科大学第三附属医院行手术治疗的宣威肺癌患者与其他地区的肺癌患者作为研究对象，用透射电镜（transmission electron microscope, TME）对患者术后标本进行超微结构的观察，探究无机颗粒物的赋存情况；对患者的血清行细胞因子检测；对术后的标本行免疫组化以及蛋白质印迹（Western blot），了解NF-κB-p65蛋白以及iNOS蛋白的表达；对肺癌组织中和尿液中的8-OHdG赋存进行检测。结果 在宣威肺癌患者癌旁组织的肺泡II型细胞、巨噬细胞中可见到大量纳米级无机物赋存；对无机物进行元素分析，含有硅（Silicon, Si）成分；宣威地区患者血清中白介素（interleukin, IL）-1β（31.50±19.16）pg/mL较其他地区肺癌患者（11.33±6.94）pg/mL高，差异有统计学意义（P<0.01）；宣威肺癌与其他地区肺癌患者的术后病理组织中癌组织有NF-κB-p65和iNOS表达，较非宣威地区明显升高；癌旁和正常组织之间未见明显差异；宣威肺癌组织和尿液8-OHdG较非宣威地区肺癌患者高，肺癌患者尿液中的8-OhdG（40.124±8.597）ng/mgCr与其他地区患者（25.673±7.986）ng/mgCr相比，差异有统计学意义（P<0.05）。结论 肺部无机物的赋存以及NF-κB-iNOS信号通路的激活可能促进了宣威肺癌的发生。.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Air Pollutants; Air Pollution, Indoor; Deoxyguanosine; Female; Humans; Lung; Lung Neoplasms; Male; Middle Aged; Nitric Oxide Synthase Type II; Transcription Factor RelA

Malignant mesothelioma is an aggressive and therapy-resistant neoplasm arising from mesothelial cells. Evidence suggests that the major pathology associated with asbestos-induced mesothelioma is local iron overload. In the present study, we induced iron-induced mesothelioma in rats based on previous reports. Ten Wistar rats were given ferric saccharate and nitrilotriacetate i.p. for 5 days a week. Five of the ten rats exhibited widespread mesotheliomas in the peritoneum and tunica vaginalis. The tumor cells showed positive immunostaining for calretinin, wilms tumor-1, podoplanin and the oxidative DNA marker 8-hydroxy-2'-deoxyguanosine. In three of the five rats with mesothelioma, array-based comparative genomic hybridization analysis identified a common chromosomal deletion mapped to the chromosomal 4q31 locus, which encompasses the TBXAS1 gene. Downregulation of the TBXAS1 gene was confirmed using quantitative PCR. TBXAS1 gene expression was also reduced in three of four human malignant pleural mesothelioma cell lines compared with normal bronchial epithelial cells. Immunohistochemistry revealed that TBXAS1 expression was weakly positive and positive in five and three out of eight human malignant mesothelioma samples, respectively. In conclusion, TBXAS1 gene expression was downregulated in rats with iron-induced mesothelioma. The relationship between iron overload and TBXAS1 downregulation should be pursued further.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Biomarkers, Tumor; Calbindin 2; Cell Cycle Proteins; Cell Line, Tumor; Chromosome Deletion; Deoxyguanosine; Down-Regulation; Ferric Compounds; Ferric Oxide, Saccharated; Glucaric Acid; Humans; Iron; Iron Overload; Lung Neoplasms; Male; Membrane Glycoproteins; Mesothelioma; Mesothelioma, Malignant; Neoplasms, Experimental; Nuclear Proteins; Rats; Rats, Wistar; RNA Splicing Factors; Thromboxane-A Synthase

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

Two types of nanosized titanium dioxide, anatase (anTiO2) and rutile (rnTiO2), are widely used in industry, commercial products and biosystems. TiO2 has been evaluated as a Group 2B carcinogen. Previous reports indicated that anTiO2 is less toxic than rnTiO2, however, under ultraviolet irradiation anTiO2 is more toxic than rnTiO2 in vitro because of differences in their crystal structures. In the present study, we compared the in vivo and in vitro toxic effects induced by anTiO2 and rnTiO2. Female SD rats were treated with 500 ?g/ml of anTiO2 or rnTiO2 suspensions by intra-pulmonary spraying 8 times over a two week period. In the lung, treatment with anTiO2 or rnTiO2 increased alveolar macrophage numbers and levels of 8-hydroxydeoxyguanosine (8-OHdG); these increases tended to be lower in the anTiO2 treated group compared to the rnTiO2 treated group. Expression of MIP1??mRNA and protein in lung tissues treated with anTiO2 and rnTiO2 was also significantly up-regulated, with MIP1??mRNA and protein expression significantly lower in the anTiO2 group than in the rnTiO2 group. In cell culture of primary alveolar macrophages (PAM) treated with anTiO2 and rnTiO2, expression of MIP1??mRNA in the PAM and protein in the culture media was significantly higher than in control cultures. Similarly to the in vivo results, MIP1??mRNA and protein expression was significantly lower in the anTiO2 treated cultures compared to the rnTiO2 treated cultures. Furthermore, conditioned cell culture media from PAM cultures treated with anTiO2 had less effect on A549 cell proliferation compared to conditioned media from cultures treated with rnTiO2. However, no significant difference was found in the toxicological effects on cell viability of ultra violet irradiated anTiO2 and rnTiO2. In conclusion, our results indicate that anTiO2 is less potent in induction of alveolar macrophage infiltration, 8-OHdG and MIP1??expression in the lung, and growth stimulation of A549 cells in vitro than rnTiO2.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adaptor Proteins, Signal Transducing; Animals; Apoptosis; Blotting, Western; Cell Proliferation; Cells, Cultured; Deoxyguanosine; Enzyme-Linked Immunosorbent Assay; Female; Humans; In Vitro Techniques; Lung; Lung Neoplasms; Photosensitizing Agents; Rats; Rats, Sprague-Dawley; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Titanium; Ultraviolet Rays

Occupational exposure to nickel compounds has been associated with lung cancer. The correlation between high nickel levels and increased risk of lung cancer has been previously reported in a case-control study. This study assessed whether nickel exposure increased the occurrence of p53 mutations due to DNA repair inhibition by nickel. A total of 189 lung cancer patients were enrolled to determine nickel levels in tumor-adjacent normal lung tissues and p53 mutation status in lung tumors through atomic absorption spectrometry and direct sequencing, respectively. Nickel levels in p53 mutant patients were significantly higher than those in p53 wild-type patients. When patients were divided into high- and low-nickel subgroups by median nickel level, the high-nickel subgroup of patients had an odds ratio (OR) of 3.25 for p53 mutation risk relative to the low-nickel subgroup patients. The OR for p53 mutation risk of lifetime non-smokers, particularly females, in the high-nickel subgroup was greater than that in the low-nickel subgroup. To determine whether nickel affected DNA repair capacity, we conducted the host cell reactivation assay in A549 and H1975 lung cancer cells and showed that the DNA repair activity was reduced by nickel chloride in a dose-dependent manner. This was associated with elevated production of hydrogen peroxide-induced 8-oxo-deoxyguanosine. Therefore, increased risk of p53 mutation due to defective DNA repair caused by high nickel levels in lung tissues may be one mechanism by which nickel exposure contributes to lung cancer development, especially in lifetime female non-smokers.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Cell Line; Deoxyguanosine; DNA Repair; Environmental Exposure; Female; Genes, p53; Humans; Lung; Lung Neoplasms; Male; Middle Aged; Mutation; Nickel; Odds Ratio; Risk Factors; Smoking; Spectrophotometry, Atomic; Taiwan

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

Asbestos is a potent carcinogen associated with increased risks of malignant mesothelioma and lung cancer in humans. Although the mechanism of carcinogenesis remains elusive, the physicochemical characteristics of asbestos play a role in the progression of asbestos-induced diseases. Among these characteristics, a high capacity to adsorb and accommodate biomolecules on its abundant surface area has been linked to cellular and genetic toxicity. Several previous studies identified asbestos-interacting proteins. Here, with the use of matrix-assisted laser desorption ionization-time of flight mass spectrometry, we systematically identified proteins from various lysates that adsorbed to the surface of commercially used asbestos and classified them into the following groups: chromatin/nucleotide/RNA-binding proteins, ribosomal proteins, cytoprotective proteins, cytoskeleton-associated proteins, histones and hemoglobin. The surfaces of crocidolite and amosite, two iron-rich types of asbestos, caused more protein scissions and oxidative modifications than that of chrysotile by in situ-generated 4-hydroxy-2-nonenal. In contrast, we confirmed the intense hemolytic activity of chrysotile and found that hemoglobin attached to chrysotile, but not silica, can work as a catalyst to induce oxidative DNA damage. This process generates 8-hydroxy-2'-deoxyguanosine and thus corroborates the involvement of iron in the carcinogenicity of chrysotile. This evidence demonstrates that all three types of asbestos adsorb DNA and specific proteins, providing a niche for oxidative modification via catalytic iron. Therefore, considering the affinity of asbestos for histones/DNA and the internalization of asbestos into mesothelial cells, our results suggest a novel hypothetical mechanism causing genetic alterations during asbestos-induced carcinogenesis.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Asbestos, Amosite; Asbestos, Crocidolite; Asbestos, Serpentine; Chromatin; Cytoskeleton; Deoxyguanosine; DNA; DNA Damage; Hemoglobins; Histones; Iron; Lung Neoplasms; Mesothelioma; Mice; Oxidation-Reduction; Proteins; Rats; Ribosomal Proteins; RNA-Binding Proteins; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Surface Properties

Early diagnosis and prevention is very important for lung cancer patients. Previous studies have emphasized that the level of coenzyme Q10 (CoQ10), present primarily in mitochondria, decreases with age and is low in patients with chronic diseases. Our goal was to find out if there is any relationship between lung cancer and CoQ10 and lipid peroxidation levels.. Blood samples from lung cancer patients were collected. Total and oxide CoQ10 levels, 8-OHdG (product of DNA damage), and malondialdehyde (MDA) levels (lipid peroxidation) were analyzed with high performance liquid chromatography (HPLC).. The MDA level (P<0.001) and DNA damage rate (8-OHdG) (P<0.001) was higher in cancer patients than in the control group; in contrast, theCoQ10 enzyme level was significantly lower (P<0.001).. The results suggest that the aforementioned parameters can be useful for lung cancer risk assessment.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Biomarkers, Tumor; Case-Control Studies; Deoxyguanosine; DNA Damage; Humans; Lipid Peroxidation; Lung Neoplasms; Malondialdehyde; Mitochondria; Oxidative Stress; Risk Assessment; Ubiquinone

Chronic inflammation has been recognized as a contributing factor in the pathogenesis of lung cancer. In this process, reactive oxygen species released by neutrophils may play an important role. The aim of the present study was to investigate the capacity of the major neutrophilic oxidant hypochlorous acid (HOCl), which is formed by myeloperoxidase (MPO), to induce DNA damage and mutagenicity in lung cells. HOCl was mutagenic in lung epithelial A549 cells in vitro, showing at physiological concentrations a significant induction of mutations in the HPRT gene. We studied three major types of DNA lesions that could be relevant for this HOCl-induced mutagenicity. Single strand DNA breakage and 8-oxo-7,8-dihydro-2'-deoxyguanosine were not found to be increased following HOCl treatment. On the other hand, HOCl caused a significant increase in the formation of 3-(2-deoxy-beta-D-erythro-pentofuranosyl)pyrimido[1,2-alpha]purin-10(3H)-one (M(1)dG), which can be formed by either malondialdehyde (MDA) or base propenals. We observed an increased MDA formation upon exposure of A549 cells to HOCl, but a role of base propenals cannot be excluded. In line with this, we observed 4-fold increased M(1)dG adduct levels in mice that were intratracheally instilled with lipopolysaccharide to induce a pulmonary inflammation with neutrophil influx. Depletion of circulating neutrophils significantly reduced pulmonary MPO activity as well as M(1)dG adducts levels, thereby providing a causal link between neutrophils/HOCl and pulmonary genotoxicity in vivo. Taken together, these data indicate that MPO catalysed formation of HOCl during lung inflammation should be considered as a significant source of neutrophil-induced genotoxicity.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenoma; Animals; Cells, Cultured; Colony-Forming Units Assay; Deoxyguanosine; DNA Adducts; DNA Breaks, Single-Stranded; DNA Damage; Humans; Hypochlorous Acid; Hypoxanthine Phosphoribosyltransferase; Inflammation; Lipid Peroxidation; Lipopolysaccharides; Lung; Lung Neoplasms; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Mutation; Neutrophils; Oxidants; Peroxidase; Purine Nucleosides

The present study investigated the effects of a preparation of a gamma-tocopherol-rich mixture of tocopherols (gamma-TmT) on chemically induced lung tumorigenesis in female A/J mice and the growth of H1299 human lung cancer cell xenograft tumors. In the A/J mouse model, the lung tumors were induced by either 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK; intraperitoneal injections with 100 and 75 mg/kg on Week 1 and 2, respectively) or NNK plus benzo[a]pyrene (B[a]P) (8 weekly gavages of 2 mumole each from Week 1 to 8). The NNK plus B[a]P treatment induced 21 tumors per lung on Week 19; dietary 0.3% gamma-TmT treatment during the entire experimental period significantly lowered tumor multiplicity, tumor volume and tumor burden (by 30, 50 and 55%, respectively; P < 0.05). For three groups of mice treated with NNK alone, the gamma-TmT diet was given during the initiation stage (Week 0 to 3), post-initiation stage (Week 3 to 19) or the entire experimental period, and the tumor multiplicity was reduced by 17.8, 19.7 or 29.3%, respectively (P < 0.05). gamma-TmT treatment during the tumor initiation stage or throughout the entire period of the experiment also significantly reduced tumor burden (by 36 or 43%, respectively). In the xenograft tumor model of human lung cancer H1299 cells in NCr-nu/nu mice, 0.3% dietary gamma-TmT treatment significantly reduced tumor volume and tumor weight by 56 and 47%, respectively (P < 0.05). In both the carcinogenesis and tumor growth models, the inhibitory action of gamma-TmT was associated with enhanced apoptosis and lowered levels of 8-hydroxydeoxyguanine, gamma-H2AX and nitrotyrosine in the tumors of the gamma-TmT-treated mice. In cell culture, the growth of H1299 cells was inhibited by tocopherols with their effectiveness following the order of delta-T > gamma-TmT > gamma-T, whereas alpha-T was not effective. These results demonstrate the inhibitory effect of gamma-TmT against lung tumorigenesis and the growth of xenograft tumors of human lung cancer cells. The inhibitory activity may be due mainly to the actions of delta-T and gamma-T.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antioxidants; Apoptosis; Benzo(a)pyrene; Cell Line, Tumor; Cell Proliferation; Deoxyguanosine; Dinoprostone; Female; gamma-Tocopherol; Histones; Leukotriene B4; Lung Neoplasms; Mice; Neovascularization, Pathologic; Nitrosamines; Tyrosine; Xenograft Model Antitumor Assays

(-)-Epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, has been shown to inhibit tumorigenesis and cancer cell growth in animal models. Nevertheless, the dose-response relationship of the inhibitory activity in vivo has not been systematically characterized. The present studies were conducted to address these issues, as well as the involvement of reactive oxygen species (ROS), in the inhibitory action of EGCG in vivo and in vitro. We characterized the inhibitory actions of EGCG against human lung cancer H1299 cells in culture and in xenograft tumors. The growth of tumors was dose dependently inhibited by EGCG at doses of 0.1, 0.3 and 0.5% in the diet. Tumor cell apoptosis and oxidative DNA damage, assessed by the formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and phosphorylated histone 2A variant X (gamma-H2AX), were dose dependently increased by EGCG treatment. However, the levels of 8-OHdG and gamma-H2AX were not changed by the EGCG treatment in host organs. In culture, the growth of viable H1299 cells was dose dependently reduced by EGCG; the estimated concentration that causes 50% inhibition (IC(50)) (20 microM) was much higher than the IC(50) (0.15 microM) observed in vivo. The action of EGCG was mostly abolished by the presence of superoxide dismutase (SOD) and catalase, which decompose the ROS formed in the culture medium. Treatment with EGCG also caused the generation of intracellular ROS and mitochondrial ROS. Although EGCG is generally considered to be an antioxidant, the present study demonstrates the pro-oxidative activities of EGCG in vivo and in vitro in the described experimental system.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Anticarcinogenic Agents; Apoptosis; Catechin; Cell Line, Tumor; Cell Proliferation; Deoxyguanosine; DNA Damage; DNA Repair; Dose-Response Relationship, Drug; Histones; Humans; Lung Neoplasms; Male; Membrane Potential, Mitochondrial; Mice; Oxidative Stress; Reactive Oxygen Species; Xenograft Model Antitumor Assays

In the present study, we investigated the relationship between the urinary excretion rate of the oxidized nucleoside 8-hydroxydeoxyguanosine (8-OHdG) and clinical factors in lung cancer patients.. The present study included 100 patients, who underwent a lung surgery. The patients included 62 men and 38 women with a mean age of 65.5 years ranging from 35 to 82. The diagnosis included 81 primary lung cancers, 9 metastatic lung cancers and 10 benign lung diseases. Urine samples collected for 24h were analyzed for the content of 8-OHdG using an ELISA assay.. The urinary excretion rate of 8-OHdG in smokers was significantly higher than that in never-smokers. Specifically, the 8-OHdG excretion rate of current smokers was higher than that of patients who had quit smoking for longer than 1 month. Excluding current smokers, the urinary excretion rate of 8-OHdG did not relate to age or gender, but to the malignant potential of the disease. The urinary 8-OHdG level increased in the order of metastatic lung cancer, primary lung cancer and benign disease. In lung cancer patients, furthermore, the mean urinary 8-OHdG level of patients with stages II-IV disease was significantly lower than that of patients with stage I disease.. Smoking significantly increased the urinary excretion rate of 8-OHdG, suggesting that smoking causes an increased rate of oxidative DNA modifications. On the other hand, the capacity to repair oxidative DNA modifications might be impaired to some extent in cancer patients.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Deoxyguanosine; Enzyme-Linked Immunosorbent Assay; Female; Humans; Lung Neoplasms; Male; Middle Aged; Neoplasm Metastasis; Oxidative Stress; Oxygen; Prospective Studies; Smoking

Resistance to chemotherapy is one of the major problems in treatment responses of lung cancer. This study explored the mechanism underlying the arsenic resistance of lung cancer. Four lung cancer cells with different proliferation activity were characterized for cytotoxicity, arsenic influx/efflux, and arsenic effects on intracellular glutathione and 8-hydroxy-2'-deoxyguanosine (8-OHdG) production. Our data revealed that relative proliferation potency of these cells was H1299>A549>CL3>H1355. Moreover, A549, H1299, and H1355 were markedly resistant to As(2)O(3) with IC50 approximately 100 microM, whereas CL3 was sensitive to As(2)O(3) with IC50 approximately 11.8 microM. After treatment with the respective As(2)O(3) at IC50, arsenic influx/efflux activity in CL3 was comparable to those in the other three arsenic-resistant cells. However, differences in glutathione levels and 8-OHdG production were also detected either before or after arsenic treatment, indicating that a certain degree of variation in anti-oxidative systems and/or 8-OHdG repair activity existed in these cell lines. By transfection of an aquaglyceroporin 9 (AQP9) gene, we showed that increased AQP9 expression significantly enhanced arsenic uptake and disrupted arsenic resistance of A549. The present study strongly suggests that membrane transporters responsible for arsenic uptake, such as AQP9, may play a critical role in development of arsenic resistance in human lung cancer cells.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Antineoplastic Agents; Aquaporins; Arsenic Trioxide; Arsenicals; Cell Line, Tumor; Deoxyguanosine; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Gene Expression Regulation, Neoplastic; Glutathione; Humans; Lung Neoplasms; Oxides

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

Oxidative stress is involved in many diseases, and the search for appropriate biomarkers is one major focus in molecular epidemiology. 8-Oxoguanine (8-oxoG), a potentially mutagenic DNA lesion, is considered to be a sensitive biomarker for oxidative stress. Another approach consists in assessing the repair capacity towards 8-oxoG, mediated predominantly by the human 8-oxoguanine DNA glycosylase 1 (hOGG1). With respect to the latter, during the last few years so-called cleavage assays have been described, investigating the incision of (32)P-labelled and 8-oxoG damaged oligonucleotides by cell extracts. Within the present study, a sensitive non-radioactive test system based on a Cy5-labelled oligonucleotide has been established. Sources of incision activity are isolated proteins or extracts prepared from cultured cells and peripheral blood mononuclear cells (PBMC). After comparing different oligonucleotide structures, a hairpin-like structure was selected which was not degraded by cell extracts. Applying this test system the impact of copper on the activity of isolated hOGG1 and on hOGG activity in A549 cells was examined, showing a distinct inhibition of the isolated protein at low copper concentration as compared to a modest inhibition of hOGG activity in cells at beginning cytotoxic concentrations. For investigating PBMC, all reaction conditions, including the amounts of oligonucleotide and cell extract as well as the reaction time have been optimized. The incision activities of PBMC protein extracts obtained from different donors have been investigated, and inter-individual differences have been observed. In summary, the established method is as sensitive and even faster than the radioactive technique, and additionally, offers the advantage of reduced costs and low health risk.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Colony-Forming Units Assay; Copper Sulfate; Deoxyguanosine; DNA Damage; DNA Glycosylases; DNA Repair; Embryo, Mammalian; Fibroblasts; Humans; Lung Neoplasms; Mice; Subcellular Fractions; Tumor Cells, Cultured

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

High incidence and poor prognosis of lung cancer make it a major health problem worldwide. Although smoking is a major cause of lung cancer, only some smokers develop lung cancer, which suggests that there is a genetic predisposition in some individuals. 8-OHG is an important oxidative base lesion and may elevate due to cancer and smoking. It is repaired by 8-hydroxyguanine DNA glycosylase 1 (OGG1), which has several polymorphisms. Although the Ser326Cys polymorphism is consistently associated with a range of cancers, findings about this polymorphism and lung cancer risk are contradictory. To date, no study has examined this association in the Turkish population. We conducted a case-control study to investigate the association between OGG1 Ser326Cys polymorphism and the risk of lung cancer using PCR-RFLP. We also evaluated gene-smoking interaction and excretion of urinary 8-OHdG. Our results suggest that the OGG1 Ser326Cys polymorphism is not a genetic risk factor for lung cancer, and that the heterozygous genotype is associated with a significantly reduced risk for lung cancer. The levels of 8-OHdG did not correlate with the polymorphism and smoking. Larger association studies are needed to validate our findings, and mechanistic studies are needed to elucidate the underlying molecular mechanisms of this association.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Case-Control Studies; Deoxyguanosine; DNA Glycosylases; Female; Genetic Predisposition to Disease; Humans; Lung Neoplasms; Male; Middle Aged; Polymorphism, Genetic; Smoking; Young Adult

Reactive oxygen species produced either endogenously or exogenously can attack lipids, proteins and DNA in human cells and cause potentially deleterious consequences. In recent years, their role in the pathogenesis of lung cancer and the preventive effect of antioxidants have been studied extensively. In this study, our aim was to investigate the levels of 8-hydroxy-2'-deoxyguanosine (8OHdG) and malondialdehyde as a marker for the effects of reactive oxygen species on DNA and lipids, the levels of antioxidant vitamins and the correlations between these oxidative stress markers and antioxidants in lung cancer.. Serum malondialdehyde, beta-carotene, retinol, and vitamins C and E were measured by high-performance liquid chromatography methods in fasting blood samples and 8OHdG was measured by gas chromatography-mass spectrometry in 24-h urine samples of patients with lung cancer (n=39) and healthy controls (n=31).. The levels of 8OHdG and malondialdehyde were significantly higher (p<0.05 and p<0.005, respectively) and beta-carotene, retinol, and vitamins C and E (p<0.0001, p<0.0001, p<0.0001, and p<0.05, respectively) were significantly lower in patients than in controls. There was a significantly positive correlation between 8OHdG and malondialdehyde (r=0.463, p=0.01) and a negative correlation between the levels of 8OHdG and retinol (r=-0.419, p=0.021) in the patient group.. Our results demonstrate that the oxidant/antioxidant balance was spoiled in favor of lipid peroxidation and DNA damage in lung cancer patients. Significant increases in the levels of malondialdehyde and 8OHdG and decreases in the levels of antioxidants suggest the possible involvement of oxidative stress in lung cancer.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Antioxidants; Ascorbic Acid; beta Carotene; Case-Control Studies; Chromatography, High Pressure Liquid; Deoxyguanosine; DNA Damage; Female; Humans; Lipid Peroxidation; Lung Neoplasms; Male; Malondialdehyde; Middle Aged; Oxidative Stress; Reactive Oxygen Species; Reference Values; Vitamin A; Vitamin E; Vitamins

PAHs (polycyclic aromatic hydrocarbons) are suspect lung cancer carcinogens that must be metabolically converted into DNA-reactive metabolites. P4501A1/P4501B1 plus epoxide hydrolase activate PAH to (+/-)- anti-benzo[ a]pyrene diol epoxide ((+/-)- anti-BPDE), which causes bulky DNA adducts. Alternatively, aldo-keto reductases (AKRs) convert intermediate PAH trans-dihydrodiols to o-quinones, which cause DNA damage by generating reactive oxygen species (ROS). In lung cancer, the types or pattern of mutations in p53 are predominantly G to T transversions. The locations of these mutations form a distinct spectrum characterized by single point mutations in a number of hotspots located in the DNA binding domain. One route to the G to T transversions is via oxidative DNA damage. An RP-HPLC-ECD assay was used to detect the formation of 8-oxo-dGuo in p53 cDNA exposed to representative quinones, BP-7,8-dione, BA-3,4-dione, and DMBA-3,4-dione under redox cycling conditions. Concurrently, a yeast reporter system was used to detect mutations in the same cDNA samples. Nanomolar concentrations of PAH o-quinones generated 8-oxo-dGuo (detected by HPLC-ECD) in a concentration dependent manner that correlated in a linear fashion with mutagenic frequency. By contrast, micromolar concentrations of (+/-)- anti-BPDE generated (+)- trans- anti-BPDE-N (2)-dGuo adducts (detected by stable-isotope dilution LC/MS methodology) in p53 cDNA that correlated in a linear fashion with mutagenic frequency, but no 8-oxo-dGuo was detected. Previous studies found that mutations observed with PAH o-quinones were predominately G to T transversions and those observed with (+/-)- anti-BPDE were predominately G to C transversions. However, mutations at guanine bases observed with either PAH-treatment occurred randomly throughout the DNA-binding domain of p53. Here, we find that when the mutants were screened for dominance, the dominant mutations clustered at or near hotspots primarily at the protein-DNA interface, whereas the recessive mutations are scattered throughout the DNA binding domain without resembling the spectra observed in cancer. These observations, if extended to mammalian cells, suggest that mutagenesis can drive the pattern of mutations but that biological selection for dominant mutations drives the spectrum of mutations observed in p53 in lung cancer.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Deoxyguanosine; DNA; Lung Neoplasms; Models, Molecular; Mutagenesis; Mutation; Polycyclic Aromatic Hydrocarbons; Protein Structure, Tertiary; Quinones; Saccharomyces cerevisiae; Tumor Suppressor Protein p53

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

Oxidative stress to DNA is recognized as a mechanism underlying carcinogenic effects of some environmental agents. Here, we hypothesized that dimethylarsinic acid (DMA(V)), an organic metabolite of inorganic arsenic in humans, might exert carcinogenic potential in a mouse line carrying a mutant Mmh allele of the Mmh/OGG1 gene encoding the enzyme 8-hydroxyguanine DNA glycosylase 1 (OGG1). Ogg1 mutant and wild type mice were treated with DMA(V) in their drinking water at a dose of 200 p.p.m. for up to 72 weeks. All DMA(V)-treated Ogg1(-/-)animals developed tumors, with a tendency for lower total incidences in the Ogg1(+/+) cases. Lung tumors in particular were induced as compared to the lack in non-carcinogen controls and were significantly more frequent in the homozygotes. At week 4, the levels of DNA 8-OH-dG and cell proliferation were significantly elevated in the lungs of non-treated Ogg1(-/-) as compared to Ogg1(+/+) mice and were strongly enhanced by DMA(V) treatment. Marked induction of Pola1, Cyp7b1, Ndfua3, Mmp13 and other genes specific to cell proliferation, cell signaling and xenobiotic metabolism in the lungs of DMA(V)-treated Ogg1(-/-) mice was found. Electron microscopic examination revealed the growth of microvilli, with increased numbers of mitochondria only in lungs and lung tumors of DMA(V)-exposed Ogg1(-/-) mice. Therefore, we strongly suggest that DMA(V) exerts carcinogenicity in the lungs of Ogg1(-/-) mutant mice, with a possible role for persistent accumulation of DNA oxidative adducts.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Apoptosis; Cacodylic Acid; Carcinogenicity Tests; Cell Proliferation; Deoxyguanosine; DNA Damage; DNA Glycosylases; DNA-(Apurinic or Apyrimidinic Site) Lyase; Female; Gene Expression Regulation, Neoplastic; Lung Neoplasms; Male; Mice; Mice, Knockout; Mutation; Oxidative Stress; Survival Rate

This study was to investigate the genotoxicity and cytotoxicity of the oil fumes formed from heating three common commercial cooking oils (soybean oil, sunflower oil, and lard) on human lung carcinoma pulmonary type II-like epithelium cell (A-549 cell). The major alkenal mutagenic compounds (trans-trans-2,4-decadienal, t-t-2,4-DDE; trans-trans-2,4-nonadienal, t-t-2,4-NDE; trans-2-decenal, t-2-DCA and trans-2-undecenal, t-2-UDA) contained in three oil fumes and their effects on the induction of reactive oxygen species (ROS) were also studied. It was found that the most potent mutagenic compound (t-t-2,4-DDE) of oil fumes was 66.4, 35.9 and 40.3 microg/g in soybean oil, sunflower oil and lard, respectively. The results indicated that the methanolic extracts of oil fumes could apparently lead to cytotoxicity and oxidative DNA damage. Glutathione (GSH) contents and the activities of antioxidant enzymes such as GSH reductase, and GSH S-transferase were adversely reduced by the methanolic extracts of oil fumes. When human A-549 cells were exposed to the methanolic extracts of oil fumes for 30 min, there was an increase in the formation of intracellular ROS, which was determined by dichlorofluorescein assay. Moreover, the methanolic extracts of oil fumes caused significant (p<0.05) oxidative damage through the 8-hydroxy-2'-deoxyguanosine formation in A-549 cells at the concentrations from 50 to 200 microg/ml. These results demonstrated that the DNA damage in A-549 cells, induced by cooking oil fumes, was related to the ROS formation. It is inferred that women exposed to emitted fumes from cooking oil were at higher risk of contracting lung cancer.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Air Pollutants; Cell Line, Tumor; Cell Survival; Comet Assay; Cooking; Deoxyguanosine; Dietary Fats; DNA Damage; Dose-Response Relationship, Drug; Epithelial Cells; Humans; Lung Neoplasms; Mutagens; Oxidative Stress; Plant Oils; Reactive Oxygen Species; Smoke; Soybean Oil; Sunflower Oil

Oxidative damage to DNA may be important in carcinogenesis and a possible risk factor for lung cancer. The urinary excretion of products of damaged nucleotides in cellular pools or in DNA may be important biomarkers of exposure to relevant carcinogens reflecting the rate of damage in steady state and may predict cancer risk. Oxidation of guanine in DNA or the nucleotide pool may give rise to 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) for urinary excretion. Oxoguanine glycosylase (OGG1) is the base excision enzyme repairing 8-oxodG in DNA by release of 8-oxoguanine. In a nested case-cohort design we examined associations between urinary excretion of 8-oxodG and risk of lung cancer as well as potential interaction with the OGG1 Ser326Cys polymorphism in a population-based cohort of 25 717 men and 27 972 women aged 50-64 years with 3-7 years follow-up. We included 260 cases with lung cancer and a sub-cohort of 263 individuals matched on sex, age and smoking duration for comparison. Urine collected at entry was analysed for 8-oxodG by HPLC with electrochemical detection. The excretion of 8-oxodG was higher in current smokers, whereas OGG1 genotype had no effect. Overall the incidence rate ratio (IRR) (95% confidence interval) of lung cancer was 0.99 (0.80-1.22) per doubling of 8-oxodG excretion and there was no interaction with OGG1 genotype. However, among never-smokers (eight cases and eight sub-cohort members) the IRR was 11.8 (1.21-115) per doubling of 8-oxodG excretion. The association between 8-oxodG excretion and lung cancer risk among never-smokers suggests that oxidative damage to DNA nucleotides is important in this group.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Chromatography, High Pressure Liquid; Cohort Studies; Deoxyguanosine; DNA; DNA Damage; Female; Follow-Up Studies; Humans; Incidence; Lung Neoplasms; Male; Middle Aged; Oxidative Stress; Polymorphism, Genetic; Prospective Studies; Risk

Measurement of the products of oxidatively damaged DNA in urine is a frequently used means by which oxidative stress may be assessed non-invasively. We believe that urinary DNA lesions, in addition to being biomarkers of oxidative stress, can potentially provide more specific information, for example, a reflection of repair activity. We used high-performance liquid chromatography prepurification, with gas chromatography-mass spectrometry (LC-GC-MS) and ELISA to the analysis of a number of oxidative [e.g., 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), 8-oxo-7,8-dihydro-guanine, 5-(hydroxymethyl)uracil], non-oxidative (cyclobutane thymine dimers) and oligomeric DNA products in urine. We analysed spot urine samples from 20 healthy subjects, and 20 age- and sex-matched cancer patients. Mononuclear cell DNA 8-oxodG levels were assessed by LC-EC. The data support our proposal that urinary DNA lesion products are predominantly derived from DNA repair. Furthermore, analysis of DNA and urinary 8-oxodG in cancer patients and controls suggested reduced repair activity towards this lesion marker in these patients.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Case-Control Studies; Chromatography, High Pressure Liquid; Colorectal Neoplasms; Deoxyguanosine; DNA; Female; Gas Chromatography-Mass Spectrometry; Humans; Leukocytes; Lung Neoplasms; Male; Middle Aged

The effects of IQ on the promotion stage of DHPN-induced lung carcinogenesis and contributions of oxidative stress were investigated in rats. Groups of 20 male 6-week-old F344 rats were given 0.1% DHPN in their drinking water for 2 weeks for initiation. From the age of 9 weeks, they were treated with 0, 150 and 300 p.p.m. of IQ in the diet for 27 weeks. Control rats were similarly fed 300 p.p.m. IQ or basal diet alone without the preceding initiation. IQ clearly (P < 0.01) enhanced the multiplicity of lung tumors in a dose-dependent manner (DHPN alone, 3.63 +/- 1.80; DHPN +150 p.p.m. IQ, 11.50 +/- 5.04; DHPN +300 p.p.m. IQ, 18.83 +/- 4.58 [no./rat]). In addition, the incidence of lung tumors in the 300 p.p.m. IQ alone group (25%) was significantly (P < 0.05) higher than that in the non-treatment group (0%). In a second experiment, male rats were given IQ at doses of 0 and 300 p.p.m. in the diet for one week in order to analyze 8-OHdG formation, levels of TBARS and BrdU-LI in the lungs. There were no changes in 8-OHdG or TBARS levels, but significant elevation of BrdU-LI occurred in the IQ administration group. The overall data clearly indicate that IQ is a potent lung carcinogen in rats, in which oxidative stress may not be involved in lung carcinogenesis.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Bromodeoxyuridine; Carcinogens; Cell Proliferation; Disease Models, Animal; DNA; DNA Damage; Guanine; Lipid Peroxidation; Lung; Lung Neoplasms; Male; Nitrosamines; Oxidative Stress; Quinolines; Rats; Thiobarbituric Acid Reactive Substances

In the present study, we examined whether the level of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) in leukocyte DNA is higher in lung cancer patients compared to controls. Factors that may influence oxidative stress, such as antioxidant vitamins, were also determined. These parameters were analyzed in 4 groups of subjects: smokers with lung cancer, ex-smokers with lung cancer, healthy smokers with comparable smoking status and healthy nonsmokers. The 8-oxodGuo mean level in leukocytes of lung cancer patients reached values of 9.22/10(6) dGuo molecules (smokers) and 11.16/10(6) dGuo molecules (ex-smokers). These values were significantly higher than in DNA of healthy smokers and nonsmokers, where mean levels reached 6.99/10(6) dGuo molecules and 5.98/10(6) dGuo molecules, respectively. Mean levels of vitamin C in the plasma of controls and lung cancer patients were 56.17 microM (nonsmokers), 26.34 microM (healthy smokers), 23.83 microM (cancer patients, smokers) and 29.19 microM (cancer patients, ex-smokers). The difference between nonsmokers and the 3 other groups was statistically significant. Vitamin E level was significantly reduced in the plasma of cancer patients (smokers 19.94 microM, ex-smokers 19.59 microM) compared to healthy smokers (28.93 microM). No changes in vitamin A concentration were found. Our results suggest that a high level of 8-oxodGuo in leukocyte DNA and a low concentration of vitamin E in the blood may predict lung cancer risk. However, it is also possible that these phenomena may simply result from disease development.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Antioxidants; Case-Control Studies; Deoxyguanosine; DNA Damage; Female; Humans; Leukocytes; Lung Neoplasms; Male; Middle Aged; Oxidative Stress; Smoking; Vitamins

Although the genotoxic mechanism(s) of hexavalent chromium (CrVI) carcinogenicity remain to be fully elucidated, intracellular reduction of CrVI and concomitant generation of reactive intermediates including reactive oxygen species and subsequent oxidative damage to DNA is believed to contribute to the process of carcinogenesis. In the current study, substantial interindividual variation (7.19-25.84% and 8.79-34.72% tail DNA as assessed by conventional and FPG-modified comet assay, respectively) in levels of DNA strand breaks after in vitro treatment of WBC with sodium dichromate (100 micromol/L, 1 hour) was shown within a group of healthy adult volunteers (n = 72) as assessed by both comet and formamidopyrimidine glycosylase-modified comet assays. No statistically significant correlation between glutathione S-transferases M1 or T1, NADPH quinone oxidoreductase 1 (codon 187) and X-ray repair cross complementation factor 1 (codon 194) genotypes and individual levels of DNA damage were observed. However, individuals homozygous for the Cys(326) 8-oxo 7,8-dihydro-2'-deoxyguanosine glycosylase 1 (OGG1) polymorphism had a statistically significant elevation of formamidopyrimidine glycosylase-dependent oxidative DNA damage after treatment with sodium dichromate when compared with either Ser(326)/Ser(326) or Ser(326)/Cys(326) individuals (P = 0.008 and P = 0.003, respectively). In contrast, no effect of OGG1 genotype on background levels of oxidative DNA damage was observed. When individuals were divided on the basis of OGG1 genotype, Cys(326)/Cys(326) individuals had a statistically significant (P < 0.05, one-way ANOVA followed by Tukey test) higher ratio of oxidative DNA damage to plasma antioxidant capacity than either Ser(326)/Ser(326) or Ser(326)/Cys(326) individuals. The results of this study suggest that the Cys(326)/Cys(326) OGG1 genotype may represent a phenotype that is deficient in the repair of 8-oxo-7,8-dihydro-2'-deoxyguanosine, but only under conditions of cellular oxidative stress. We hypothesize that this may be due to oxidation of the Cys(326) residue. In conclusion, the homozygous Cys(326) genotype may represent a biomarker of individual susceptibility of lung cancer risk in individuals that are occupationally exposed to CrVI.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Carcinogens, Environmental; Chromates; Chromium; Comet Assay; Deoxyguanosine; DNA Damage; DNA Glycosylases; Female; Genotype; Humans; Leukocytes; Lung Neoplasms; Male; Middle Aged; Occupational Exposure; Oxidative Stress; Phenotype; Polymorphism, Genetic

Oxidative DNA damage plays an important role in carcinogens-induced carcinogenesis. 8-hydoxy-2deoxy-guanosine (8-OH-dG), a biomarker of oxidative DNA damage, plays important roles in initiation, progression, and prognosis of lung cancer, and closely relates with mutations of k-ras and p53 genes in carcinogenesis of lung tissue. This study was to detect protein expressions of 8-OH-dG, k-ras, and p53 genes in lung cancer tissues, and to analyze their values in distinguished diagnosis of lung cancer.. Protein levels of 8-OH-dG, k-ras, and p53 in pleural effusion cells from 53 patients with lung cancer, and 53 patients with other benign lung diseases were detected by immunocytochemistry.. Positive rates of 8-OH-dG, k-ras, and p53 protein in cancer group were significantly higher than those in benign disease group [75.5% (40/53) vs. 15.1% (8/53), P < 0.01; 64.2% (34/53) vs. 3.8% (2/53), P < 0.01; and 69.8% (37/53) vs. 18.9% (10/53), P < 0.01; respectively]. Protein levels of 8-OH-dG, k-ras, and p53 protein in cancer group were 1.68+/-1.21, 1.32+/-1.06, and 1.57+/-1.15,respectively. Rank correlation analysis showed that protein expression of 8-OH-dG positively correlated with those of k-ras (RS=0.643, P < 0.01), and p53 (RS=0.827, P < 0.01)u protein expression of k-ras positively correlated with that of p53 (RS=0.897, P < 0.01).. Protein expressions of 8-OH-dG, k-ras, and p53 are up-regulated in pleural effusion cells of lung cancer, and have mutual relations. They may be used as reference markers in diagnosing and screening for lung cancer.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Deoxyguanosine; Gene Expression Regulation, Neoplastic; Genes, p53; Genes, ras; Humans; Lung Neoplasms; Pleural Effusion, Malignant; ras Proteins; Tumor Suppressor Protein p53; Up-Regulation

Ambient particulate matter (PM) has been associated with increased risk of lung cancer. One proposed mechanism is that PM induces oxidative stress mediated by transition metals contained within this mixture. We examined the relationship between the personal exposure to water-soluble transition metals in PM(2.5) and oxidative DNA damage. In 49 students from central Copenhagen, we determined PM(2.5) exposure by personal sampling twice in 1 year, and measured in these PM(2.5) samples the concentration of the soluble transition metals vanadium, chromium, iron, nickel, copper, and platinum. Collected lymphocytes and 24-hour urine samples were analyzed for DNA damage in terms of 7-hydro-8-oxo-2'-deoxyguanosine (8-oxodG). We found that the 8-oxodG concentration in lymphocytes was significantly associated with the vanadium and chromium concentrations with a 1.9% increase in 8-oxodG per 1 microg/L increase in the vanadium concentration and a 2.2% increase in 8-oxodG per 1 microg/L increase in the chromium concentration. We have previously reported that in this study population the personal exposure to PM(2.5) was associated with an increase in 8-oxodG in lymphocytes. However, vanadium and chromium were associated with the 8-oxodG concentration in lymphocytes independently of the PM(2.5) mass concentration. The four other transition metals were not associated with 8-oxodG in lymphocytes and none of the transition metals was significantly associated with 8-oxodG in urine. Our results could indicate that vanadium and chromium present in PM(2.5) have an effect on oxidative DNA damage that is independent of particle mass and/or other possible toxic compounds contained within this particulate mixture.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Biomarkers; Denmark; Deoxyguanosine; DNA Damage; Environmental Pollutants; Female; Humans; Lung Neoplasms; Male; Metals, Heavy; Middle Aged; Oxidative Stress; Particle Size; Seasons; Students

Nitropyrenes (NPs) present in diesel and gasoline emissions are mutagenic and carcinogenic in experimental animals. Nitro-reduction of 1-NP causes oxidative stress. It is unclear whether 8-hydroxydeoxyguanosine (8-OH-dG) is produced from 1-NP and whether it contributes to the carcinogenic activity of 1-NP. In this study, we measured the level of reactive oxygen species (ROS) in cultured human lung epithelial cells after exposure to 1-NP and the intracellular level of 8-OH-dG and expression level of the 8-OH-dG repair enzymes. As results, 1-NP induced the generation of 8-OH-dG via ROS, but 8-OH-dG repair enzymes prevented an increase of 8-OH-dG formation in cellular DNA of the A549 cell line below 250 microM of 1-NP. These data suggest that 1-NP can induce oxidative DNA damage by generation of ROS, which may play a role in the carcinogenesis induced by 1-NP. These data also suggest that individuals with impaired DNA repair enzymes might be more susceptible to lung cancer induced by 1-NP.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Cell Culture Techniques; Cell Line; Deoxyguanosine; DNA Damage; DNA Repair Enzymes; Humans; Japan; Lung Neoplasms; Mutagens; Oxidative Stress; Pyrenes

Lung specimens were collected from 161 non-smoking male patients with carcinoma to determine the deposition of carbon particles and oxidative damage in lung tissues. Morphologically, carbon particles deposited in human lungs with carcinoma were similar to those of diesel exhaust like particles, and mass of particles showed a significant increase with the increasing age of the patients. An increasing age of patient with carcinomas was also associated with 8-oxodeoxy-guanosine (8-oxo-dG) formation, which was analyzed using the HPLC-electrochemical detector method. In addition, it was found that 8-oxo-dG increased in cancerous tissues rather than in non-cancerous ones. To determine whether particles in lung tissues were associated with 8-oxo-dG formation, carbon particles deposited in lung tissues were partially purified by cycling of alkali fusion with 1 M KOH; mutagenic chemicals in particles were extracted and excluded by removal with an equal volume of benzene/methanol and dichloromethane. It was also found that 8-oxo-dG was formed by non-mutagenic particles, and enhanced in the in vivo test using mouse rather than in the in vitro using RAW 254.7 tissue cultured cells. The 8-oxo-dG formation in vivo was due to the fact that hydroxyl radicals might be involved with phagocytosis of non-mutagenic particles in inflammatory cells, and the mutation was induced by hydroxylation of guanine residue on DNA. These results were also demonstrated by the occurrence of alveolar macrophages and neutrophils after intratracheal instillation of particles. These observations suggest that small particles from lung cancer patients further promote oxidative damage when used to treat the mouse lung. Especially, particles from which organic chemicals were removed were highly reactive to oxidative damage and formed 8-oxo-dG.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Animals; Carbon; Cell Line; Child; Deoxyguanosine; Dose-Response Relationship, Drug; Female; Humans; Lung; Lung Neoplasms; Macrophages, Alveolar; Male; Mice; Mice, Inbred BALB C; Mice, Inbred ICR; Microscopy, Electron, Scanning; Middle Aged; Monocytes; Particle Size; Pyrenes

We investigated the relationship between lung- and skin-tumor promotion and oxidative stress caused by administration of dimethylarsinic acid (DMA(V)) in mice. The incidence of lung tumors induced by lung tumor initiator (4NQO) and DMA(V) were, as well as 8-oxo-2'-deoxyguanosine (8-oxodG), suppressed by cotreatment with (-)epigallocatechin gallate (EGCG). When mice were topically treated with trivalent dimethylated arsenic (DMA(III)), a further reductive metabolite of DMA(V), not only an increase in skin tumors but also an elevation of 8-oxodG in epidermis were observed. These results suggest that tumor promotion due to DMA(V) administration is mediated by DMA(III) through the induction of oxidative stress.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenoma; Administration, Topical; Animals; Cacodylic Acid; Carcinogenicity Tests; Carcinogens; Deoxyguanosine; Female; Herbicides; Lung Neoplasms; Male; Mice; Mice, Hairless; Oxidative Stress; Skin Neoplasms

This study investigates the genotoxicity and cytotoxicity of oil fumes, formed when peanut oil is heated, on human lung carcinoma pulmonary type II-like epithelium cells. The major mutagenic compound (trans-trans-2,4-decadienal, t-t-2,4-DDE) contained in oil fumes and its effect on the induction of reactive oxygen species (ROS) is also discussed. The results indicate that the methanolic extract of oil fumes can apparently lead to cytotoxicity and oxidative DNA damage. Glutathione (GSH) content, and the activities of antioxidative enzymes such as GSH reductase, GSH peroxidase and GSH S-transferase were adversely reduced by the methanolic extract of oil fumes. t-t-2,4-DDE could produce superoxide anion, hydrogen peroxide and hydroxyl radicals in a phosphate buffer (pH 7.4), and form intracellular ROS, determined by dichlorofluorescein assay in A-549 cells. Moreover, t-t-2,4-DDE caused significant (P <0.05) oxidative damage of the 8-hydroxy-2'-deoxyguanosine formation in A-549 cells at concentrations from 50 to 200 microM. These results demonstrated that the DNA damage in A-549 cells, induced by t-t-2,4-DDE, was related to the ROS formation. The occurrence of t-t-2,4-DDE, therefore, was of significance in the genotoxicity of oxidized oil and fumes.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Aldehydes; Cell Line, Tumor; Cell Survival; Comet Assay; Deoxyguanosine; DNA Damage; Dose-Response Relationship, Drug; Hot Temperature; Humans; Lipid Peroxidation; Lung Neoplasms; Mutagens; Oxidative Stress; Plant Oils; Reactive Oxygen Species; Smoke

The broad spectrum of oxidative DNA damage biomarkers [urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OH-dGuo) and 8-hydroxyguanine (8-OH-Gua)] and the level of oxidative DNA damage and repair in leukocytes DNA were analyzed in three groups of subjects: (a) lung cancer patients [all smokers (n = 51)]; (b) healthy smokers with comparable smoking status (n = 26); and (c) healthy nonsmokers (n = 38). The mean level of 8-OH-Gua in urine samples of 38 healthy nonsmokers reached a value of 1.783 +/- 0.785 nmol/day/kg. This level was significantly lower than that in the urine of the two smoker groups (cancer patients and healthy smokers), in whom the levels reached values of 2.319 +/- 1.271 and 2.824 +/- 0.892 nmol/day/kg, respectively. Urinary excretion of 8-OH-dGuo was similar in all groups of subjects. The level of 8-OH-dGuo in DNA isolated from leukocytes of cancer patients was significantly higher than that in DNA isolated from the group of healthy smokers and nonsmokers (9.44 +/- 4.77 versus 7.20 +/- 2.83 and 5.88 +/- 2.47 molecules/10(6) deoxyguanosine, respectively). Repair activity of 8-OH-Gua, as estimated by the nicking assay, was significantly higher in blood leukocytes of healthy volunteers (44.6 +/- 20.21 and 37.54 +/- 13.43 pmol/h/mg protein for smokers and nonsmokers, respectively) than in the leukocytes of lung cancer patients (24.56 +/- 11.28 pmol/h/mg protein). Because oxidative DNA insult represented by urinary excretion of oxidative DNA lesions was similar in both groups of subjects with similar smoking status, it appears likely that a higher rate of generation of oxidative damage in cellular DNA of lung cancer patients is a result of deficiency of the repair mechanism(s) in this group.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Biomarkers; Deoxyguanosine; DNA Damage; DNA Repair; Female; Genetic Predisposition to Disease; Humans; Lung Neoplasms; Male; Middle Aged; Oxidation-Reduction; Oxidative Stress

To investigate the relationship among 8-OH-dG and the development of human lung cancer and cancer related genes, an 8-OH-dG-specific monoclonal antibody and biotin-streptavidin immuno-staining were used to detect the 8-OH-dG in 150 cases of human lung cancer tissues, 120 adjacent lung tissues without cancer cells, 40 benign lung lesions and 40 normal lung tissues. The expressions of P53, C-MYC, K-RAS, BCL-2 and hTERT(human telomerase reverse transcriptase) were determined by immunohistochemistry and the relationship among the 8-OH-dG and these genes was analyzed. The 8-OH-dG were positive in 139 of 150 (92.7%) lung cancer specimens, and the percentage of adduct labeling cell in lung cancer specimens was (24.00 +/- 25.11)% (mean +/- SE). 21 of 120 (17.5%) adjacent lung tissues were adduct positive, and the percentage of adduct labeling cell was 2.42 +/- 5.98%. 4 of 40 (10.0%) benign lung lesions were adduct positive, and the percentage of adduct labeling cell was 0.80 +/- 1.30%, whereas 2 of 40 (5.0%) normal lung tissues were weak positive with 8-oh-dG, and the percentage of adduct labeling cell in this group was (0.34 +/- 1.01)%. The level of 8-OH-dG in lung cancer tissues was significantly higher than that of adjacent lung tissues, benign lung lesions and normal lungs (P < 0.01). The lung cancer patients were stratified by sex, age, cell types and smoking history, but these characteristics were not correlated with the level of 8-OH-dG. In the investigation of the relationship between the 8-OH-dG and five cancer related genes, higher 8-OH-dG levels were observed in lung cancer patients with over-expression of K-RAS and BCL-2 than those of negative expressed patients (P-value were 0.035 and 0.034 respectively), whereas the expression of P53, C-MYC and hTERT were not correlated with level of 8-OH-dG. 8-OH-dG was an important biomarker that may reflect the oxidative DNA damages of cells, and 8-OH-dG may affect K-RAS and BCL-2 genes in the carcinogenesis of lung cancer.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Deoxyguanosine; DNA Damage; DNA-Binding Proteins; Gene Expression; Humans; Immunohistochemistry; Lung; Lung Neoplasms; Proto-Oncogene Proteins c-bcl-2; Proto-Oncogene Proteins c-myb; ras Proteins; Telomerase; Tumor Suppressor Protein p53

Dimethylarsinic acid (DMA), a major metabolite of inorganic arsenics, and arsenic exposure is associated with tumor development in a wide variety of human tissues. In the present study, we examined whether DMA has tumor-promoting activity on rat lung carcinogenesis initiated with N-bis(2-hydroxypropyl)nitrosamine (DHPN). Male, 8-week-old, F344 rats were treated with DHPN at a concentration of 0.1% in drinking water for 1 week, and starting 1 week thereafter, DMA was administered at concentrations of 0, 100, 200 or 400 ppm in the drinking water for 30 weeks. Induction of epithelial lesions, classified as alveolar epithelial hyperplasia, adenoma, and adenocarcinoma was evident in the lungs of DHPN-initiated animals, but no significant differences were found between DMA-treated groups and control groups. Furthermore, no significant differences in 5-bromo-2'-deoxyuridine labeling indices, as a marker of cell proliferation were observed among the groups. An additional group treated with DMA at concentrations of 200 ppm alone, without prior DHPN initiation was found to develop no epithelial lesions in the lung. There was no significant gain in 8-hydroxydeoxyguanosine formation, as a marker of oxidative stress, in the lungs of rats treated with DMA in their drinking water. In conclusion, oral-administered DMA does not exert promoting effects on rat lung carcinogenesis initiated with DHPN.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Administration, Oral; Animals; Arsenicals; Carcinogens; Cell Survival; Deoxyguanosine; Lung; Lung Neoplasms; Male; Mutagens; Nitrosamines; Pulmonary Alveoli; Rats; Rats, Inbred F344

Hexavalent chromium is a genotoxic human pulmonary carcinogen that elevates DNA oxidation, apparently through the generation of reactive DNA-damaging intermediates including Cr(V), Cr(IV) and reactive oxygen species. We tested the hypothesis that elevation of DNA oxidation may also be through inhibition of the expression of the repair glycosylase for 8-oxo deoxyguanine (hOGG1) in cultured A549 human lung epithelial cells. Treatment with sodium dichromate (0-100 microM, 16 h) resulted in a concentration-dependent decrease in the levels of OGG1 mRNA as measured by both RT-PCR and RNase protection assay. Sodium dichromate at 25 microM and above gave a marked reduction of OGG1 mRNA expression which was not seen at 1 microM and below. No effect on the expression of the apurinic endonuclease hAPE or the house-keeping gene GAPDH was observed at any of the concentrations of sodium dichromate investigated. Treatment of cells with the pro-oxidant H(2)O(2) (0-200 microM) for 16 h had no detectable effect on the levels of OGG1 mRNA or protein expression suggesting that the effect of sodium dichromate is not mediated by H(2)O(2). Western blotting demonstrated that sodium dichromate (100 microM; 16 h and >25 microM; 28 h) markedly reduced levels of OGG1 protein in nuclear cell extracts. Additionally, treatment of cells with sodium dichromate (>25 microM, 28 h) resulted in a concentration-dependent decrease in the ability of nuclear extracts to nick a synthetic oligonucleotide containing 8-oxo deoxyguanine (8-oxo dG). We conclude that the elevation of 8-oxo dG levels observed in A549 cells treated with sodium dichromate may be, at least in part, due to a reduced capacity to repair endogenous and hexavalent chromium-induced 8-oxo dG.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenosine Triphosphate; Blotting, Western; Cell Extracts; Chromates; Deoxyguanosine; DNA Repair; DNA-Formamidopyrimidine Glycosylase; Down-Regulation; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Humans; Hydrogen Peroxide; In Situ Nick-End Labeling; Lung Neoplasms; N-Glycosyl Hydrolases; Nuclear Proteins; Reactive Oxygen Species; RNA, Messenger; Tumor Cells, Cultured

Reactive nitrogen species, such as peroxynitrite, nitrogen oxides and nitryl chloride, have been implicated as a cause of diverse pathophysiological conditions, including inflammation, neurodegenerative and cardiovascular diseases and cancer. We previously reported that 8-nitroguanine is formed by reactions of guanine or calf-thymus DNA with peroxynitrite in vitro. In the present study, we have studied the formation of 8-nitroguanosine and 8-oxo-7,8-dihydroguanosine in reactions of calf-liver RNA with various reactive nitrogen species. 8-Nitroguanosine in RNA was found to be much more stable than 8-nitro-2' -deoxyguanosine in DNA, which rapidly depurinates to release 8-nitroguanine. Both 8-nitroguanosine and 8-oxo-7,8-dihydroguanosine were formed in calf-liver RNA following exposure to various reactive nitrogen species, such as synthetic peroxynitrite. They were also formed in RNA by reactive species formed from nitric oxide and superoxide anion generated concomitantly from 3-morpholino-sydnonimine (SIN-1) and those formed with myeloperoxidase or horseradish peroxidase in the presence of nitrite and hydrogen peroxide. 8-Nitroguanosine was detected by HPLC with an electrochemical detector in enzymatic hydrolyzates of RNA isolated from human lung carcinoma cells incubated with synthetic peroxynitrite. Our results indicate that 8-nitroguanosine in cellular RNA could be measured as a marker of damage caused by endogenous reactive nitrogen species in tissues and cells.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Biomarkers; Carcinoma; Cattle; Deoxyguanosine; Guanine; Humans; Lung Neoplasms; Molsidomine; Peroxynitrous Acid; RNA, Neoplasm; Tumor Cells, Cultured

In experiments using the renal carcinogen ferric nitrilotriacetate (Fe-NTA) in male ddY mice, primary pulmonary cancers were also induced in bronchiolar and alveolar tissues. 4-Hydroxy-2-nonenal (4-HNE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), products of oxidative processes, increased in bronchiolar and alveolar cells after administration of Fe-NTA. These substances disappeared after oral administration of propolis or artepillin C, as shown histochemically, and correlated with an anticancer prophylactic effect of propolis and artepillin C. From our investigation, lipid peroxidation seems to play an important role in pulmonary carcinogenesis. Malignant progression from adenoma of bronchiolar or alveolar origin to malignant tumors has been proposed to involve a stepwise transformation. In our study, adenomas developed into adenocarcinomas and large cell carcinomas after treatment with Fe-NTA. In contrast, after oral administration of propolis or artepillin C, adenomas did not progress to carcinomas. Instead of developing into large cell cancers, as induced by Fe-NTA in control mice, adenomas showed remarkable proliferation of macrophages and local anti-oxidant activity after treatment with either propolis or artepillin C. Propolis and artepillin C therefore appear to inhibit lipid peroxidation and the development of pulmonary cancers.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Antineoplastic Agents; Deoxyguanosine; Ferric Compounds; Immunohistochemistry; Lipid Peroxidation; Lung Neoplasms; Male; Mice; Nitrilotriacetic Acid; Nuclear Proteins; Phenylpropionates; Proliferating Cell Nuclear Antigen; Propolis; Thyroid Nuclear Factor 1; Transcription Factors

The purpose of this study is to examine the carotenoid effects on lung tumorigenesis induced by intratracheal instillation of diesel exhaust particles (DEP) into mice weekly for 20 wk. It was suggested that active oxygen radicals might play an important role in DEP-induced lung tumorigenesis. Mice were divided to 4 groups of diet containing 0.02% of palm oil carotene, 0.02% of beta-carotene, or no carotenoid with or without DEP. The BF group (4% fat) and the HF group (16% fat) were prepared for each diet group. The experimental period was 12 mo. By the administration of palm oil carotene, neither adenocarcinoma nor adenoma was found in the BF group. In the HF group with palm oil carotene, no adenocarcinoma was observed, and adenoma was reduced. Adenoma in the HF group was not greatly reduced by beta-carotene, but rather increased in the BF group. No adenocarcinoma was found in either the BF or the HF groups with beta-carotene. The 8-hydroxydeoxyguanosine/deoxyguanosine ratio in palm carotene groups was lower than in the other groups, while that in beta-carotene groups was not. From these results, palm oil carotene was suggested to prevent lung tumorigenesis by its protective effect on DNA from active oxygen. Beta-carotene was supposed to have different effects from palm oil carotene on lung tumorigenesis. Besides the chemopreventive effect, the growth of mice was inhibited by the administration of palm oil carotene. Further studies are necessary to elucidate the mechanisms of carotenoid effects.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Adenoma; Animals; Antioxidants; beta Carotene; Carotenoids; Deoxyguanosine; Dietary Fats; DNA Damage; Growth; Lung; Lung Neoplasms; Male; Mice; Mice, Inbred ICR; Reactive Oxygen Species; Time Factors; Vehicle Emissions; Vitamins

Hexavalent chromium [Cr(VI)] is a genotoxic carcinogen for which inhalation is a major potential route of exposure in occupational settings. In the present study, the ability of sodium dichromate to cause DNA strand breaks in three populations of cells, human whole blood cells, isolated human peripheral blood lymphocytes and cultured A549 lung epithelial cells, was investigated. Treatment with non-cytotoxic concentrations of sodium dichromate (for 1 h) resulted in a concentration-dependent increase in the number of DNA strand breaks as measured by the Comet assay. The lowest concentrations of sodium dichromate that resulted in a statistically significant (P < 0.01) increase in the number of DNA strand breaks were 500, 50 and 10 microM, respectively, in these cells. The use of formamidopyrimidine glycosylase increased the sensitivity of detection of strand breaks in A549 cells 10-fold, suggesting a role for DNA base oxidation in the mechanism of dichromate-induced DNA strand breaks. In support of this hypothesis, immunocytochemistry indicated an elevation of 8-oxodeoxyguanosine in A549 cells treated with 10 and 500 microM sodium dichromate for 1 h. We also demonstrated 2.11- and 2.5-fold ranges in the level of control and dichromate (500 microM)-induced DNA strand breaks, respectively, in cells of whole blood within a group of healthy volunteers (n = 26). A statistically significant (P < 0.001) positive Pearson's correlation (r = 0.606) was found between control and treated levels of DNA strand breaks, suggesting that factors responsible for relatively low levels of DNA strand breaks in untreated PBL may also offer protection against the formation of dichromate-induced DNA strand breaks.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adolescent; Adult; Cells, Cultured; Chromates; Chromium; Comet Assay; Deoxyguanosine; DNA; DNA Damage; DNA, Neoplasm; Female; Humans; Immunohistochemistry; Lung Neoplasms; Lymphocytes; Male; Middle Aged; Oxidative Stress; Tumor Cells, Cultured

The purpose of this study was to examine the level of smoking-related aromatic DNA adducts and oxidative DNA damage in current smokers from a lung cancer case-control study in African Americans and Mexican Americans. In addition, mutagen sensitivity (bleomycin-induced chromatid breaks), a marker of genetic susceptibility, was assessed in these patients and correlated with the level of DNA damage. Lymphocyte DNA from cases and age-, sex-, and ethnicity-matched controls was analyzed for aromatic DNA adducts (43 cases and 47 controls) and the level of 7, 8-dihydro-8-oxo-2'-deoxyguanosine (8-oxo-dG) was determined in 46 cases and 48 controls using (32)P-postlabeling. Overall, lung cancer cases had significantly (P < 0.05) higher levels of aromatic DNA adducts and 8-oxo-dG (mean+/-SEM; 6.03+/-1.16/10(8) nucleotides and 5.82+/-0.77/10(5) nucleotides, respectively) compared to the controls (2.80+/-0.36/10(8) nucleotides and 3.65+/-0.56/10(5) nucleotides, respectively). The case-control differences for these two biomarkers were especially evident in current smokers. Both male and female lung cancer cases had higher levels of aromatic DNA adducts compared to the corresponding controls but only in men was the difference statistically significant (P=0.002). Cases who started smoking at earliest age had highest levels of aromatic DNA adducts and 8-oxo-dG. The level of aromatic DNA adducts in lung cancer cases, but not controls, was positively correlated with bleomycin-induced chromatid breaks (P=0.011). In contrast, the level of 8-oxo-dG was not correlated with mutagen sensitivity in either cases or controls or with the level of aromatic DNA adducts. The data suggest that levels of both aromatic DNA adducts and 8-oxo-dG may be useful in predicting risk of lung cancer in these minority populations. The correlation between aromatic DNA adducts and mutagen sensitivity in lung cancer cases and the trend for higher levels of DNA damage in cancer cases who started smoking earliest are particularly interesting and merit further study.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Black People; Case-Control Studies; Deoxyguanosine; DNA; DNA Adducts; Female; Humans; Lung Neoplasms; Lymphocytes; Male; Mexican Americans; Middle Aged; Minority Groups; Risk Factors; Smoking; Texas

Polymorphic genes for the peroxide scavenger glutathione peroxidase I (GPX1) and 8-hydroxydeoxyguanosine (8-OHdG) DNA glycosylase/apurinic (AP) lyase (hOGG1) map to loci on chromosome 3p which are subject to frequent loss of heterozygosity (LOH) in lung tumours. Levels of the pro-mutagenic, oxidative DNA lesion 8-OHdG, were measured in 37 paired normal and tumorous lung specimens using HPLC with electrochemical detection. Lung tumours were also analysed for 3p LOH by fluorescent PCR with Genescan analysis. No significant difference was observed between 8-OHdG levels in tumour [7.7 +/- 6.7 (mean +/- SE) 8-OHdG/10(6) 2'-deoxyguanosine (dG)] and normal (8.1 +/- 8.8 8-OHdG/10(6) dG) lung tissue. Adduct levels in normal lung tissue DNA were not associated with constitutive hOGG1 genotype although there was a trend towards lower 8-OHdG levels in individuals possessing the ALA6 GPX1 polymorphism. Lung tumours exhibiting 3p LOH (40%) contained higher levels of 8-OHdG adducts (10.9 +/- 2.6 8-OHdG/10(6) dG) (P = 0.05) and lower GPX1 enzyme activity [45.5 nmol glutathione (GSH)/min/mg] (P = 0.09) when compared with tumours without LOH at these sites (5.55 +/- 0.87 8-OHdG/10(6) dG and 63.6 nmol GSH/min/mg, respectively). In conclusion, tumours with 3p LOH at loci associated with hOGG1 and GPX1 appear to have compromised oxidative defence mechanisms as measured by reduced GPX1 enzyme activity and elevated 8-OHdG levels and this may affect the prognosis of lung cancer patients.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Amino Acid Substitution; Carcinoma, Squamous Cell; Chromosomes, Human, Pair 3; Deoxyguanosine; DNA Adducts; DNA-Formamidopyrimidine Glycosylase; DNA, Neoplasm; Female; Genotype; Glutathione Peroxidase; Humans; Isoenzymes; Loss of Heterozygosity; Lung Neoplasms; Male; N-Glycosyl Hydrolases; Neoplasm Proteins; Oxidative Stress; Polymorphism, Genetic; Smoking

The hOGG1 gene encodes a DNA glycosylase that excises 8-hydroxyguanine (oh8Gua) from damaged DNA. Structural analyses of the hOGG1 gene and its transcripts were performed in normal and lung cancer cells. Due to a genetic polymorphism at codon 326, hOGG1-Ser326 and hOGG1-Cys326 proteins were produced in human cells. Activity in the repair of oh8Gua was greater in hOGG1-Ser326 protein than in hOGG1-Cys326 protein in the complementation assay of an E. coli mutant defective in the repair of oh8Gua. Two isoforms of hOGG1 transcripts produced by alternative splicing encoded distinct hOGG1 proteins: one with and the other without a putative nuclear localization signal. Loss of heterozygosity at the hOGG1 locus was frequently (15/ 23, 62.2%) detected in lung cancer cells, and a cell line NCI-H526 had a mutation leading to the formation of the transcripts encoding a truncated hOGG1 protein. However, the oh8Gua levels in nuclear DNA were similar among lung cancer cells and leukocytes irrespective of the type of hOGG1 proteins expressed. These results suggest that the oh8Gua levels are maintained at a steady level, even though multiple hOGG1 proteins are produced due to genetic polymorphisms, mutations and alternative splicing of the hOGG1 gene.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Alleles; Alternative Splicing; Cell Line; Codon; Cysteine; Deoxyguanosine; DNA; DNA Damage; DNA Repair; DNA-Formamidopyrimidine Glycosylase; Gene Frequency; Genes; Genetic Variation; Genotype; Humans; Leukocytes, Mononuclear; Loss of Heterozygosity; Lung Neoplasms; Mutation; N-Glycosyl Hydrolases; Polymorphism, Genetic; Serine; Transcription, Genetic; Tumor Cells, Cultured

The 8-hydroxydeoxyguanosine (8-OH-dG) levels in the peripheral parts of human lung tissues were compared between lung cancer patients (n=70) and non-cancer patient controls (n=15). An increased level of 8-OH-dG was observed in the lung cancer group, in both the adenocarcinoma and non-adenocarcinoma (mainly squamous cell carcinoma) groups, as compared to the non-cancer control group. This result suggests that reactive oxygen species are partly involved in the induction of lung carcinomas (both adenocarcinoma and non-adenocarcinoma).

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Deoxyguanosine; DNA; DNA Damage; Female; Humans; Lung; Lung Neoplasms; Male; Middle Aged; Reactive Oxygen Species

In order to clarify the involvement of oxygen radicals in lung carcinogenesis induced by diesel exhaust particles (DEP), the relationship between lung tumour response and formation of 8-hydroxydeoxyguanosine (8-OHdG) in lung DNA was examined. The role of high dietary fat and beta-carotene on these responses was also studied. Mice were intratracheally injected with 0.05, 0.1 and 0.2 mg of DEP per animal once weekly for 10 weeks. After 12 months, the lung tumour incidence in mice treated with 0.05 mg and 0.1 mg showed similar increases (30% and 31%), but was decreased to 24% at 0.2 mg. High dietary fat enhanced the incidence of both benign and malignant tumours. beta-carotene partially prevented the tumour development. After the 10 weekly treatments of DEP, inflammatory reaction was observed in the respiratory tract and alveoli. The formation of 8-OHdG in lung DNA from mice treated with DEP showed a dose dependent increase. 8-OHdG formation was enhanced by high dietary fat and partially reduced by beta-carotene. Formation of 8-OHdG was significantly correlated with the lung tumour incidence except at 0.2 mg. These results suggest that the induction of oxidative DNA damage may be an important factor in the initiation of DEP-induced lung carcinogenesis, and that beta-carotene and high dietary fat may play a role in the regulation of tumour development via modulation of the formation of 8-OHdG.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Body Weight; Carcinogenicity Tests; Deoxyguanosine; Dietary Fats; DNA; DNA Damage; Incidence; Lung; Lung Neoplasms; Lymphoma; Male; Mice; Mice, Inbred ICR; Neoplasms, Experimental; Vehicle Emissions

Exposure of rats to quartz (or various other particles) can lead to the development of lung tumors. At the moment, the mechanisms involved in particle-induced tumor formation are not clarified. However, it is suggested that inflammation, in conjunction with the production of reactive oxygen species (ROS) and an enhancement of epithelial cell proliferation, may play a key role in the development of lung tumors. ROS induces 8-oxoguanine (8-oxoGua) and other mutagenic DNA oxidation products, which can be converted to mutations in proliferating cells. Mutation formation in cancer-related genes is a critical event with respect to tumor formation. In this study we investigated the effects of quartz (DQ12) and of the nontumorigenic dust corundum on the induction of 8-oxoGua in the DNA of rat lung cells, as well as on cell proliferation and pulmonary inflammation. Wistar rats were exposed by intratracheal instillation to quartz (2.5 mg/rat) or corundum (2.5 mg/rat) suspended in physiological saline; control animals exposed to physiological saline or left untreated. Measurements were carried out 7, 21, and 90 days after the exposures. 8-oxoGua levels were determined in lung tissue sections at the single cell level by immunocytological assay using a rabbit anti-8-oxoGua antibody. After exposure to quartz, 8-oxoGua levels were significantly increased at all time points of investigation. Additionally, we observed inflammation and an enhanced cell proliferation. Exposure to corundum had no adverse effects on the lung; neither increased 8-oxoGua levels nor enhanced cell proliferation or inflammation were detected. These observations support the suggestion that inflammation associated with increased 8-oxoGua levels in lung cells and increased cell proliferation is an important determinant for particle-induced development of lung tumors in the rat.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Air Pollutants; Animals; Bronchoalveolar Lavage Fluid; Cell Division; Deoxyguanosine; Dust; Guanine; Image Processing, Computer-Assisted; Immunohistochemistry; Lung; Lung Neoplasms; Quartz; Rabbits; Rats; Rats, Wistar; Reactive Oxygen Species

We analyzed the level of 8-oxo-2'-deoxyguanosine in lymphocytes DNA of cancer patients undergoing radiotherapy. The results of this work indicate that exposure of cancer patients to therapeutic doses of ionizing radiation causes significant increase of the amount of 8-oxo-dG in DNA isolated from their lymphocytes.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Chromatography, High Pressure Liquid; Colorectal Neoplasms; Deoxyguanosine; DNA, Neoplasm; Dose-Response Relationship, Drug; Electrochemistry; Humans; Individuality; Lung Neoplasms; Lymphocytes; Male; Middle Aged; Spectrophotometry, Ultraviolet

The tobacco-specific N-nitrosamine, NNK, is a potent carcinogen in laboratory animals. The authors have shown previously that NNK-induced lung tumorigenesis in A/J mice can be reduced significantly by certain nonsteroidal antiinflammatory drugs (NSAIDs), such as sulindac, ibuprofen, or piroxicam treatments. In this study, the authors investigated whether NSAIDs could reduce NNK-induced oxidative, DNA damage and/or inhibit endogenous lipid peroxidation, or prostaglandin E2 (PGE2) synthesis in A/J mice. In the first experiment, A/J mice were gavaged with NNK (112 mumol/kg b.w.) three times a week while being maintained on a diet to which either ibuprofen (263 mg/kg diet), naproxen (230 mg/kg), sulindac (123 mg/kg), piroxicam (25 mg/kg), indomethacin (5 mg/kg), or no NSAIDs had been added. Levels of 8-OH-dG in the DNA of lung and liver were measured by high-performance liquid chromatography with electron capture detector. Treatment with NSAIDs had no significant effects on the endogenous or NNK-induced formation of 8-OH-dG in the lung of the mice. In a second experiment, after treatment of A/J mice with NSAIDs for 2 weeks, lipid peroxidation was assayed by determining thiobarbituric acid-reactive substances (TBA-RS) in lung tissues, and prostaglandin E2 levels were measured in plasma by an enzyme immunoassay. Treatments with some NSAIDs lowered the levels of lipid peroxidation and plasma levels of PGE2 below basal levels. Taken together, these results suggest that the inhibition of NNK-induced lung tumorigenesis by NSAIDs is more likely related to an inhibition of prostaglandin synthesis than to a direct inhibition of lipid peroxidation or oxidative DNA damage induced by NNK.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Deoxyguanosine; Dinoprostone; DNA; DNA Damage; Female; Ibuprofen; Lipid Peroxidation; Liver; Lung; Lung Neoplasms; Mice; Mice, Inbred A; Naproxen; Nitrosamines; Oxidation-Reduction; Oxidative Stress; Piroxicam; Sulindac

Occupational exposure to silica has often been associated with the development of pulmonary fibrosis and, occasionally, lung cancer. Their development may be mediated by oxidant-induced cellular injury. The short- and long-term effects of a single intratracheal instillation of silica in rats (10 mg/200 microliters/saline per rat) was assessed by measuring 8-hydroxy-2'-deoxyguanosine (oh8dG) levels in lung tissue and peripheral blood leukocytes. Cell differentials, reduced glutathione (GSH), and superoxide dismutase (SOD), lipid peroxide, and total phospholipids in peripheral blood and/or bronchoalveolar lavage fluid (BALF) were also measured. The pulmonary oh8dG levels increased approximately 2.24- 2.86-fold from 1 to 5 days after exposure to silica. It was still elevated 1 and 4 weeks after installation, but the difference was no longer statistically significant. The oh8dG levels in peripheral blood leukocytes were never significantly different, but they were generally higher than in the controls. The low SOD levels in the BALF of exposed rats in the early stage and the higher GSH levels in the late stage may represent protective reactions against the generation of oxygen species. A significant increase in oh8dG levels in lung tissue suggested the possible carcinogenicity of silica.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Bronchoalveolar Lavage Fluid; Cell Differentiation; Deoxyguanosine; Disease Models, Animal; DNA Damage; Glutathione; Leukocytes; Lipid Peroxidation; Lung; Lung Neoplasms; Male; Occupational Exposure; Oxidative Stress; Phospholipids; Pulmonary Fibrosis; Rats; Rats, Wistar; Silicon Dioxide; Specific Pathogen-Free Organisms; Superoxide Dismutase; Trachea

In this study we examined the effects of green tea and its major components, (-)-epigallocatechin gallate (EGCG) and caffeine, on the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in A/J mice. We also studied the effects of green tea and EGCG on O6-methylguanine and 8-hydroxydeoxyguanosine (8-OH-dGuo) formation in lung tissues caused by NNK treatment. Mice were given 2% tea, 560 ppm EGCG, or 1120 ppm caffeine in drinking water for 13 weeks. During this time, NNK (11.65 mg/kg body weight) was administered by gavage three times weekly for 10 weeks from weeks 3 to 12. The bioassay was terminated 6 weeks after the last NNK treatment. Mice treated with NNK developed 22.5 lung adenomas per mouse, whereas NNK-treated mice that drank green tea or EGCG as drinking water developed only 12.2 (P less than 0.01) and 16.1 (P less than 0.05) tumors per mouse, respectively. Mice that drank green tea or caffeine solution showed lower body weight gains, although little difference in water and diet consumption was noted in these groups. While green tea and EGCG exerted little effect on the formation of O6-methylguanine, a critical DNA lesion in NNK lung tumorigenesis, both treatments suppressed the increase of 8-OH-dGuo levels in mouse lung DNA. The inhibition of 8-OH-dGuo formation in lung DNA by green tea and EGCG is consistent with their ability to inhibit lung tumorigenesis by NNK. Because 8-OH-dGuo is a DNA lesion caused by oxidative damage, these results suggest that the mechanism of inhibition by green tea and EGCG in NNK-induced lung tumorigenesis is due at least partly to their antioxidant properties.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Caffeine; Carcinogens; Catechin; Deoxyguanosine; DNA; Female; Guanine; Liver; Lung; Lung Neoplasms; Mice; Mice, Inbred A; Nitrosamines; Tea