Interactions between paraoxonase 1 genetic polymorphisms and smoking and their effects on oxidative stress and lung cancer risk in a Korean population

Genome-wide gene-bisphenol A, F and triclosan interaction analyses on urinary oxidative stress markers

BACKGROUND

Bisphenols and triclosan (TCS) are common endocrine disrupters (EDCs) that may induce oxidative stress. However, there is limited information as to whether these EDCs interact with genetic variants to modify the levels of oxidative stress on a genome-wide scale.

METHODS

We first performed a genome-wide scan among a Chinese population and also measured three urinary EDCs, including bisphenol A (BPA), bisphenol F (BPF) and TCS, and three urinary oxidative stress markers [4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), 8-iso-prostaglandin-F_2α (8-isoPGF_2α) and 8-hydroxy-deoxyguanosine (8-OHdG)]. Subsequently, we examined interactions between three urinary EDCs and nearly 4.6 million genetic variants for three urinary oxidative stress markers by the general linear model.

RESULTS

Urinary BPA, BPF and TCS were positively associated with HNE-MA, 8-isoPGF_2α and 8-OHdG. Significant rs6855040 (4p15.32/between SNORA75B and QDPR)-BPA, rs1112943 (4q35.1/SNX25)-TCS interactions were associated with the 8-isoPGF_2α levels (all P < 5 × 10^-8). In addition, rs4656116 (1p22.3/CACL1), rs16958760 (17p11.2/between USP43 and DHRS7C) and rs11651078 (17p11.2/LOC339260) showed significant gene-TCS interactions with 8-OHdG (all P < 5 × 10^-8). The gene-level analysis found significant interaction between SNX25 and TCS for 8-isoPGF_2α levels (P < 2.12 × 10^-6).

CONCLUSION

Our results identify several gene-EDCs interactions for oxidative stress, highlighting that EDCs may modify the effect of genetic variants on oxidative stress.

Association of PON1, TNF-α and TGF-β gene polymorphisms with prognosis in oral and oropharyngeal squamous cell carcinoma

OBJECTIVE

The oral and oropharyngeal squamous cell carcinoma (OOSCC) accounts for 90-95% of tumours in the oral cavity. Single nucleotide polymorphism (SNP) in the coding region of PON1, tumour necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β) have been associated with to development of different cancers. Our aim was to investigate the prognostic value of PON1 (rs854560 and rs662), TNF-α (rs1800629 and rs361525) and TGF-β (rs1800469) SNPs in OOSCC.

MATERIALS AND METHODS

We genotyped 163 OOSCC patients and 146 patients from group of control for PON1 (rs854560 and rs662), TNF-α (rs1800629 and rs361525) and TGF-β (rs1800469) SNPs by real-time polymerase chain reaction (PCR).

RESULTS

TNF-α (rs1800629) GG genotype was significantly more frequent in intraoral lesions and clinical stages III and IV, while the polymorphic AA genotype in lip lesion and clinical stages I and II. Moreover, TGF-β (rs1800469) AG and AA genotypes were significantly more frequent in larger tumours (T3 e T4). TNF-α (rs1800629) AG genotype had poor survival and patients carrying the PON1 (rs662) TT genotype tended to poor survival.

CONCLUSIONS

Results suggest that the rs1800629 and rs1800469 could exert influence in the more aggressive behaviour of OOSCC and the genotypes AG of rs1800629, and TT of rs662 could be markers with prognostic value in OOSCC.

Genetic variants in xenobiotic detoxification enzymes, antioxidant defenses and hormonal pathways as biomarkers of susceptibility to prostate cancer

Cancer is considered a complex disease that in many cases results from the interaction between chemical exposures, either from environmental or dietary sources, and genetic polymorphisms of xenobiotic-metabolizing enzymes (XME) or antioxidant enzymatic defenses. This study explored associations and interactions between genetic and environmental risk factors on the risk of prostate cancer (PCa) in 323 subjects that underwent prostate biopsy due to prostate specific antigen (PSA) levels above 4 ng/ml (161 PCa and 162 non-PCa). Eleven genes involved directly or indirectly in xenobiotic detoxification, oxidative stress and estrogen signaling were studied (GSTM1, GPX1 (rs1050450 and rs17650792), NAT2 (rs1801280), TXNRD1 (rs7310505), PRDX3 (rs3740562), CYP17A1 (rs743572), PON1 (rs662), SOD1 (rs10432782), SOD2 (rs4880), CAT (rs1001179), and ESR1 (rs746432)). A structured questionnaire was administered to all individuals to assess environmental and dietary chemical exposures. Medical data was collected by urologists. GPX1 rs17650792 polymorphism was the only one showing a significant inverse association with PCa risk. PRDX3 and GPX1 (rs17650792) genetic polymorphisms were significantly associated with Gleason score and PSA levels, respectively. The intake of nuts and soya products was associated with a reduced risk of PCa, as well as the performance of physical activity. Moreover, a number of gene-environmental interactions were found to increase the risk of PCa, particularly exposure to pesticides and rs1801280 (NAT2) and tobacco smoking and rs1050450 (GPX1). These findings suggest that the association of genetic and environmental risk factors with PCa risk should be assessed jointly for a better understanding of this complex disease.

Assessment of PPARGC1A, PPARGC1B, and PON1 Genetic Polymorphisms in Esophageal Squamous Cell Carcinoma Susceptibility in the Eastern Chinese Han Population: A Case-Control Study Involving 2351 Subjects

Previous studies suggested that alterations in the energy metabolism might be underlying cancer initiation and progression. Polymorphisms of genes involved in energy metabolism regulation, such as peroxisome proliferator-activated receptor gamma coactivator 1α (PPARGC1A), -β (PPARGC1B), and paraoxonase 1 (PON1), might confer susceptibility to esophageal squamous cell carcinoma (ESCC) and partially explain its pathogenesis. We investigated the effects of several single nucleotide polymorphisms (SNPs) in three metabolic-related genes (e.g., PPARGC1A, PPARGC1B, and PON1) on ESCC susceptibility. In total, 829 patients with sporadic ESCC and 1522 nontumor controls were enrolled in the study. SNPs were genotyped using PCR-ligase detection reaction. Our study revealed that the PPARGC1A rs3736265 G/A SNP significantly increased the risk for ESCC (GA vs. GG: adjusted odds ratio [OR] = 1.25, 95% confidence interval [95% CI] = 1.02-1.54, p = 0.034; GA+AA vs. GG: adjusted OR = 1.25, 95% CI = 1.03-1.52, p = 0.027]. In addition, a stratified analysis revealed that the PPARGC1A rs3736265 SNP was correlated with the development of ESCC in male and nondrinking subgroups. We also confirmed that the PPARGC1B rs17572019 G/A SNP promoted the risk of ESCC in subgroup with high alcohol intake. The PPARGC1A rs8192678 C/T polymorphism decreased the susceptibility of ESCC in men. These findings highlight that polymorphisms in PPARGC1A and PPARGC1B may contribute to ESCC susceptibility. In the future, further well-designed epidemiological studies are needed to confirm our findings.

Urinary 8-OHdG as a Biomarker for Oxidative Stress: A Systematic Literature Review and Meta-Analysis

Oxidative stress reflects a disturbance in the balance between the production and accumulation of reactive oxygen species (ROS). ROS are scavenged by the antioxidant system, but when in excess concentration, they can oxidize proteins, lipids, and DNA. DNA damage is usually repaired, and the oxidized products are excreted in urine. 8-hydroxy-2-deoxyguanosine is considered a biomarker for oxidative damage of DNA. It is needed to define background ranges for 8-OHdG, to use it as a measure of oxidative stress overproduction. We established a standardized protocol for a systematic review and meta-analysis to assess background ranges for urinary 8-OHdG concentrations in healthy populations. We computed geometric mean (GM) and geometric standard deviations (GSD) as the basis for the meta-analysis. We retrieved an initial 1246 articles, included 84 articles, and identified 128 study subgroups. We stratified the subgroups by body mass index, gender, and smoking status reported. The pooled GM value for urinary 8-OHdG concentrations in healthy adults with a mean body mass index (BMI) ≤ 25 measured using chemical methods was 3.9 ng/mg creatinine (interquartile range (IQR): 3 to 5.5 ng/mg creatinine). A significant positive association was observed between smoking and urinary 8-OHdG concentrations when measured by chemical analysis. No gender effect was observed.

The Association between PON1 (Q192R and L55M) Gene Polymorphisms and Risk of Cancer: A Meta-Analysis Based on 43 Studies

Q192R and L55M polymorphism were considered to be associated with the development of multiple cancers. Nevertheless, the results of these researches were inconclusive and controversial. Therefore, we conducted a meta-analysis of all eligible case-control studies to assess the association between PON1 (Q192R and L55M) gene polymorphisms and risk of cancer. With the STATA 14.0 software, we evaluated the strength of the association by using the odds ratios (ORs) and 95% confidence intervals (CIs). A total of 43 case-control publications 19887 cases and 23842 controls were employed in our study. In all genetic models, a significant association between PON1-L55M polymorphisms and overall cancer risk was observed. Moreover, in the stratified analyses by cancer type, polymorphism of PON1-L55M played a risk factor in the occurrence of breast cancer, hematologic cancer, and prostate cancer. Similarly, an increased risk was observed in the Caucasian and Asian population as well as hospital-based group and population-based group. For PON1-Q192R polymorphisms, in the stratified analyses by cancer type, PON1-Q192R allele was associated with reduced cancer risks in breast cancer. Furthermore, for racial stratification, there was a reduced risk of cancer in recession model in Caucasian population. Similarly, in the stratification analysis of control source, the overall risk of cancer was reduced in the heterozygote comparison and dominant model in the population-based group. In conclusion, PON1-Q192R allele decreased the cancer risk especially breast cancer; there was an association between PON1-L55M allele and increased overall cancer risk. However, we need a larger sample size, well-designed in future and at protein levels to confirm these findings.

Serum Paraoxonase-1-Related Variables and Lipoprotein Profile in Patients with Lung or Head and Neck Cancer: Effect of Radiotherapy

We investigated alterations in the levels of the antioxidant paraoxonase-1 (PON1) and the lipoprotein profile (analyzed by nuclear magnetic resonance) in patients with lung cancer (LC) or head and neck cancer (HNC), and the effects produced thereon by radiotherapy (RT). We included 33 patients with LC and 28 patients with HNC. Before irradiation, and one month after completion of RT, blood samples were obtained. The control group was composed of 50 healthy subjects. Patients had significantly lower serum PON1 activity and concentration before RT than the control group. PON1-related variables were good predictors of the presence of LC or HNC, with analytical sensitivities and specificities greater than 80%. Patients showed a significant increase in the number of particles of all subclasses of very-low-density lipoproteins (large, medium and small). However, these changes were not maintained when adjusted for age, sex, and other clinical and demographic variables. Irradiation was associated with a significant increase in PON1 concentration and, only in patients with HNC, with an increase in high-density lipoprotein-cholesterol concentration. Our results suggest that determinations of the levels of PON1-related variables may constitute good biomarkers for the evaluation of these diseases. Studies with a larger number of patients are needed to fully confirm this hypothesis.

Association between paraoxonase-1 gene Q192R and L55M polymorphisms and risk of gastric cancer: A case-control study from Iran

The aim of the present study was to examine the relation between two paraoxonase1 (PON1) polymorphisms, Q192R and L55M and susceptibility to gastric cancer in an Iranian population. In this case-control study the PON1 polymorphisms were assessed in 90 gastric cancer patients and 90 healthy controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Regarding PON1 Q192R polymorphism, a significant increase in the R allele in the patient group compared with the controls (p value = 0.0006) While the Q allele was more frequent in the control group. No significant difference was found in the genotype or allele frequency of the L55M polymorphism between healthy individuals and patients with gastric cancer. Our results demonstrated the protective effect of Q allele against gastric cancer.

High-Density Lipoprotein Components and Functionality in Cancer: State-of-the-Art

Cancer is the second leading cause of death in western countries, and thus represents a major global public health issue. Whilst it is well-recognized that diet, obesity, and smoking are risk factors for cancer, the role of low levels of high-density lipoprotein cholesterol (HDL-C) in cancer is less well appreciated. Conflicting evidence suggests that serum HDL-C levels may be either positively or negatively associated with cancer incidence and mortality. Such disparate associations are supported in part by the multitude of high-density lipoprotein (HDL) functions that can all have an impact on cancer cell biology. The aim of this review is to provide a comprehensive overview of the crosstalk between HDLs and cancer, focusing on the molecular mechanisms underlying this association.

Effects of Glutathione S-Transferase Gene Polymorphisms and Antioxidant Capacity per Unit Albumin on the Pathogenesis of Chronic Obstructive Pulmonary Disease

OBJECTIVES

To study the effects of GSTM1, GSTT1 gene polymorphisms, and organism antioxidant capacity and related indicators such as antioxidant capacity per unit of albumin (AC/ALB) on chronic obstructive pulmonary disease (COPD).

METHODS

Using polymerase chain reaction technology, GSTM1 and GSTT1 gene polymorphisms were detected in 33 COPD patients and 33 healthy people. The total antioxidant capacity (TAC) found in serum was determined using the I₂/KI potentiometric, KMnO₄ microtitration, and H₂O₂ potentiometric methods. The AC/ALB was defined as the TAC divided by the serum albumin concentration. Logistic regression analysis was carried out with biochemical screening indices, which was found to be closely related with the incidence of COPD.

RESULTS

The GSTM1 and GSTT1 gene deletion rate in the COPD group was significantly higher than that in the control group (P < 0.05). The differences in serum TAC between the COPD and control groups, GSTM1 (+) and GSTM1 (-) groups, and GSTT1 (+) and GSTT1 (-) groups were statistically significant (P < 0.001). In addition, there was a significant difference in the AC/ALB between the COPD and control groups (P < 0.05). Logistic regression analysis showed that the incidence of COPD was closely related to the AC/ALB (P < 0.05).

CONCLUSIONS

GSTM1 and GSTT1 gene polymorphisms are closely correlated with the pathogenesis of COPD, while the AC/ALB plays a decisive role in the occurrence and development of COPD.

Association between Paraoxonase 1 polymorphisms and risk of esophagogastric junction adenocarcinoma: a case-control study involving 2,740 subjects

Esophagogastric junction adenocarcinoma (EGJA) is a serious public health problem with high mortality in China. In this study, we assessed the association between Paraoxonase 1 (PON-1) rs662 C>T, rs854560 A>T polymorphisms and EGJA risk. This case-control study enrolled 2,740 participants of Asians origin from the Eastern Chinese Han populations. SNPscanTM genotyping assay was harnessed to determine the genotyping of PON1 polymorphisms. The PON-1 rs854560 A>T and rs662 C>T genotypes distribution accorded with Hardy–Weinberg equilibrium. We found that there was no difference in the frequency of PON-1 rs662 C>T, rs854560 A>T genotypes between the overall EGJA cases and controls. In the subgroup analyses, the results indicated that PON-1 rs662 C>T polymorphism might be associated with a significantly decreased risk of EGJA in ever smoking group (TT vs. CC/CT: adjusted OR = 0.58, 95% CI 0.35–0.95, P = 0.029). In conclusion, our study highlights PON-1 rs662 C>T polymorphism may decrease the risk of EGJA, which interacts with the tobacco using. In the future, a fine-mapping case-control study with detailed gene-environmental data is needed to further assess these potential relationship.

Paraoxonase-1 (PON1) induces metastatic potential and apoptosis escape via its antioxidative function in lung cancer cells

Paraoxonase-1 (PON1) gene polymorphisms have been closely associated with the development of advanced cancers while PON1 secretion to the serum is linked with inhibition of oxidized high-density lipoprotein by its antioxidative function. Our group previously demonstrated that post-translational modification of serum PON1 in form of fucosylated PON1 is a potential biomarker of small cell lung cancer. Here, we interrogated the role of PON1 in the pathobiology of lung cancer (LC) by addressing cell-autonomous mechanisms using gain-of-function and loss-of-function approaches and protein expression profiling of tissue samples in our clinical biobank. PON1 expression in LC patient tissues varied between overexpression in squamous cell carcinoma and minimal loss in adenocarcinoma sub-types. Simultaneous overexpression of PON1 both at the gene and protein stability levels induced pro-oncogenic characteristics in LC cells and xenografts. PON1 overexpression supported metastatic progression of LC by decreasing G1/S ratio and LC cell senescence involving p21Waf1/Cip1. PON1 suppressed drug- and ligand-induced cell death and protected LC cells from genotoxic damages with maintained ATP levels, requiring p53-directed signals. PON1 promoted ROS deregulation protecting the mitochondria from dysregulation. PON1 knockdown resulted in the blockage of its antioxidant function in LC cells through Akt signaling with reduced invasive signature as a consequence of scant expression. Targeted glycolysis stimulated PON1 antioxidant activity regulating phosphorylation of AMPK-α. The functional data imply that exploitation of the antioxidative function of PON1 is consequential in driving LC pathogenesis at the cell-autonomous mechanistic level with consequences on tumor growth.

Smoking-promoted oxidative DNA damage response is highly correlated to lung carcinogenesis

Oxidative stress induced by tobacco smoking is one of the main causes of DNA damage and is known to be involved in various cancers. Smoking is the leading cause of lung cancer, while the role of cigarette smoke-induced oxidative DNA damage response during lung carcinogenesis is largely unknown. In this study, we investigated oxidative DNA damage response levels in smoking and nonsmoking patients with lung cancer, and evaluated the potential diagnostic value of 8-OHdG for lung cancer. We observed a higher level of 8-OHdG expression and secretion in airways of lung cancer patients than that of noncancer controls. 8-OHdG expression was associated with the TNM stages. Additionally, cigarette smoke-induced oxidative DNA damage response was observed in bronchial epithelial cells in vitro and in vivo. A statistical significance correlation was found between the levels of 8-OHdG and smoking index. With a cut-off value of 2.86 ng/ml, 8-OHdG showed a sensitivity and specificity of 70.0% and 73.7%, respectively, to identify a patient with lung cancer. These findings not only underscore the importance of smoking in oxidative DNA damage response of lung cancer patients, but also suggest 8-OHdG as a potential diagnostic biomarker for lung cancer.

Association Between COX-2 Polymorphisms and Lung Cancer Risk

BACKGROUND Multiple relevant risk factors for lung cancer have been reported in different populations, but results of previous studies were not consistent. Therefore, a meta-analysis is necessary to summarize these outcomes and reach a relatively comprehensive conclusion. MATERIAL AND METHODS STATA 12.0 software was used for all statistical of the relationship between COX-2 polymorphisms and lung cancer risk. Inter-study heterogeneity was examined with the Q statistic (significance level at P<0.1). The publication bias among studies in the meta-analysis was analyzed with Begg's funnel plot and Egger's test. Hardy-Weinberg equilibrium was tested in all controls of the studies. RESULTS COX-2 rs20417 polymorphism had a significant association with reduced risk of lung cancer under homozygous and recessive models, and similar results were observed in white and population-based subgroups under 2 and 3 contrasts, respectively. Additionally, rs2066826 polymorphism manifested a strong correlation with increased risk of lung cancer under 5 genetic models. CONCLUSIONS In COX-2 gene, rs20417 may have a certain relationship with reduced risk of lung cancer, while rs2066826 may increase the risk of lung cancer.

Association of Paraoxonase 1 Gene Polymorphisms With the Risk of Hepatitis B Virus-related Liver Diseases in a Guangxi Population: A Case-control Study

Paraoxonase 1 (PON1), a liver-induced glycoprotein enzyme responsible for antioxidant defense against reactive oxygen species and anti-inflammatory, has been linked to various cancers. The objective of this study was to explore the association of PON1 rs662 and rs705382 with the risk of chronic hepatitis B (CHB), hepatitis B virus-related liver cirrhosis (LC), and hepatocellular carcinoma (HCC) in patients living in the Guangxi region of southern China. The PON1 rs662 and rs705382 single-nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 99 CHB patients, 84 LC patients, 258 HCC patients, and 221 healthy controls.Significant associations with CHB risk were observed for the rs705382 SNP after adjusting for sex, age, ethnicity, smoking, alcohol consumption, and body mass index. When stratified by sex and age, this positive association was significantly strengthened among men and individuals over 40 years old. Moreover, a decreased risk of LC was associated with the rs705382 CG and the combined GG + CG genotypes among women, with borderline statistical significance. In haplotype analyses, the haplotype GA was associated with a 1.68-fold increase in the risk of HCC.Our results showed that the PON1 rs705382 SNP might be a risk factor for CHB in Guangxi populations.