Polymorphisms in DNA repair genes in lung cancer patients living in a coal-mining region.

Air pollutants and ionizing radiation are well-known carcinogens involved in the pathogenesis of lung cancer, and residents of coal-mining regions are exposed routinely to these agents. Polymorphisms in DNA repair genes may be associated with an increased risk of malignant transformation. We investigated associations between the risk of lung cancer in residents of the coal-mining region and polymorphisms in the genes APEX1 (rs1130409), hOGG1 (rs1052133), XRCC1 (rs25489, rs25487), XRCC2 (rs3218536), XRCC3 (rs861539), ADPRT/PARP1 (rs1136410), XPD/ERCC2 (rs13181), XPG/ERCC5 (rs17655), XPC (rs2228001), ATM (rs1801516), and NBS1 (rs1805794). Three hundred and forty residents of the Kemerovo Region (a coal-mining region of western Siberia) were lung cancer patients exposed to air pollutants and ionizing radiation (case) and 335 were healthy donors (control). Genotyping was performed by real-time PCR and allele-specific PCR. We discovered that polymorphisms in the XPD gene in men [log-additive model: odds ratio (OR) = 1.64, 95% confidence interval (CI): 1.17-2.31], the ATM gene in women and nonsmokers (codominant model: OR = 0.11, 95% CI: 0.02-0.49 and OR = 0.25, 95% CI: 0.08-0.72, respectively), the APEX1 gene for smokers (recessive model: OR = 2.55, 95% CI: 1.34-4.85), and the NBS1 gene for those who work in the coal industry (overdominant model: OR = 0.40, 95% CI: 0.21-0.75) are associated with an increased risk of lung cancer. Using the multifactor dimensionality reduction method, we found a model of gene-gene interactions associated with the risk of lung cancer: NBS1 (rs1805794)-XRCC1 (rs25487)-hOGG1 (rs1052133)-XPG (rs17655). These results indicate an association between combinations of polymorphisms in the studied genes and the risk of lung cancer in residents of a coal-mining region.

Idiotypic and anti-idiotypic antibodies against polycyclic aromatic hydrocarbon in human blood serum are new biomarkers of lung cancer.

Evaluation of epidemiologic risk factor in relation to lung cancer invoked by polycyclic aromatic hydrocarbons has been inconsistent. To address this issue, we conducted a prospective evaluation of new biomarkers for lung cancer classified according levels of idiotypic and anti-idiotypic antibodies against polycyclic aromatic hydrocarbons in human blood serum. The blood serums of 557 lung cancer patients and 227 healthy donors were analysis of these antibodies by ELISA. Collected data were regrouped and analyzed by gender, smoking, and age as predictors of risk lung cancer factors. Also, the data of lung cancer patients were additionally analyzed by stages and types of lung cancer, surgery, and chemotherapy. It was suggested to use ratio of idiotypic and anti-idiotypic antibodies rather than distinguish level each of them separately. The ratio of levels in healthy people was 3.32 times higher than in lung cancer patients. This approach gave more precisely results and great prognostic value. The logistic regression model (AUC = 0.9) and neural networks (AUC = 0.95) were built to compare lung cancer patients and healthy donors by predictors. The ELISA data of 49 people random sampled from the originally ELISA data and ELISA data of 52 coal miners as a group of lung cancer risk were confirmed logistic regression model. So, suggested idiotypic and anti-idiotypic antibodies against polycyclic aromatic hydrocarbons were not only shown difference between healthy donors and lung cancer patients also elicited group of lung cancer risk among healthy people.

Chromosome aberrations in peripheral blood lymphocytes of lung cancer patients exposed to radon and air pollution.

Lung cancer is one of the most common forms of cancer. The aim of this study was to validate chromosome aberrations in peripheral blood lymphocytes of lung cancer patients living in a region with high air pollution and increased background radon levels as a biomarker of cancer risk. A total of 417 lung cancer patients and 468 control participants were analysed using a chromosome aberration assay in peripheral blood lymphocytes. The results showed that chromatid-type aberrations (2.26±1.58 vs. 1.60±1.58) and chromosome-type aberrations (CSAs) (0.96±1.36 vs. 0.42±0.70) in lung cancer patients were increased significantly in comparison with the controls. The most significant two-fold increase was detected for CSAs (nonsmoking patients: 0.84±1.54 vs. 0.41±0.73%, smoking patients: 0.99±1.31 vs. 0.44±0.67%). The frequency of dicentric and ring chromosomes, double minutes and rogue cells was significantly higher (P=0.002, 0.00002, 0.01, 0.0007) in the lung cancer patients. As both analysed groups lived in the same environment, our results show that increased radon levels were not the only source for the detected genome damage. Using binomial logistic regression, the estimated odds ratios and 95% confidence intervals adjusted for the main confounders (smoking, occupational exposure, age) were 1.31 (1.20-1.40) for chromatid-type aberrations, 1.28 (1.17-1.33), and 1.68 (1.49-1.88) for CSAs. It may be suggested that lung cancer patients show a significant increase in genome damage that may be caused by an interplay between exposure and individual low capacity of DNA repair, leading to genome instability.