Polymorphisms in the caspase-8 gene and the risk of lung cancer

Caspase-8 (CASP-8) is an initiator CASP in the cell death receptor-mediated apoptotic pathway, and plays an important role in the development of cancer. Polymorphisms and their haplotypes in the CASP-8 gene can result in alterations in CASP-8 expression and/or activity, thereby modulating the susceptibility to lung cancer. To test this hypothesis, we examined the association of -678_-673delAGTAAG (-678del) and IVS12-19G-->A polymorphisms and their haplotypes with the risk of lung cancer in a Korean population. The CASP-8 genotypes were determined in 432 lung cancer patients and 432 healthy age- and gender-matched control subjects. The distributions of the CASP-8 -678del and IVS12-19G-->A genotypes were not significantly different between the overall lung cancer cases and the controls. When the cases were categorized by tumor histology, however, the IVS12-19 AA genotype and the combined IVS12-19 GA + AA genotype were associated with a significantly decreased risk of small cell carcinoma (SmCC) compared with the IVS12-19 GG genotype [adjusted odds ratio (OR) = 0.14, 95% confidence interval (CI) = 0.03-0.64, P = 0.01; and adjusted OR = 0.56, 95% CI = 0.33-0.96, P = 0.03, respectively]. Consistent with the genotyping analyses, the -678del-/IVS12-19A haplotype containing 94% of the IVS12-19A allele in the study population was associated with a significantly decreased risk of SmCC compared with the -678del-/IVS12-19G (adjusted OR = 0.58, 95% CI = 0.36-0.93, P = 0.023, and Pc = 0.046). These findings suggest that the CASP-8 gene may contribute to an inherited predisposition to SmCC of the lung.     

Correlation between survivin genetic polymorphisms and lung cancer susceptibility

Aims: The purpose of the study was to analyze the relationship of survivin polymorphisms including -31G/C, -625G/C, 9194A/G and 9809T/C with the susceptibility to lung cancer. Methods: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to test the polymorphisms of -31G/C, -625G/C, 9194A/G and 9809T/C in 104 patients with lung cancer and 104 healthy controls. Then, linkage disequilibrium and haplotypes were analyzed by HaploView software. The differences of genotype, allele and haplotype frequencies in case and control group were assessed via chi-square test. Odds ratio (OR) with 95% CI were used to evaluate the correlation of survivin polymorphisms with lung cancer. Results: Genotype distribution of each polymorphism site in control group was in agreement with Hardy-Weinberg equilibrium (HWE) (P>0.05). The frequency of -31G/C CC genotype and C allele in case group were much higher than that of controls, respectively (CC: 33.6% vs. 22.1%; C: 57.2% vs. 46.6%) and CC genotype as well as C allele were appeared to be risk factors for lung cancer. Meanwhile, 9194A/G GG genotype could increase the risk for lung cancer (OR=2.86, 95% CI=1.14-7.20). The risk of G allele carriers for lung caner was higher than that of A allele (OR=1.63, 95% CI=1.08-2.47). The haplotypes analysis indicated that CGGC and GCAT were associated with the susceptibility to lung cancer (OR=2.79, 95% CI=1.58-4.92; OR=2.36, 95% CI=1.29-4.30). Conclusions: Survivin -31G/C and 9194A/G polymorphisms were associated with the risk of lung cancer. The CGGC and GCAT haplotypes carriers were more likely to develop lung cancer.     

CD40 -1C>T polymorphism and the risk of lung cancer in a Chinese population

Background: The co-stimulatory molecule CD40 plays an important role in anti-tumor responses by promoting cytotoxic T lymphocyte (CTL) activity and differentiation of helper T cells. Growing evidence suggests that single nucleotide polymorphisms (SNPs) in CD40 are associated with the susceptibility to cancer. This study investigated the association between the CD40 -1C/T SNP (rs1883832) and lung cancer in a Chinese population. Methods: We conducted a hospital-based case-control study including 105 lung cancer patients and 109 healthy control subjects. The -1C/T SNP in CD40 was genotyped by the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), and its association with lung cancer susceptibility was evaluated. Results: The distribution of the genotypes of CD40-1C/T was significantly different between lung cancer patients and controls. The frequency of the TT genotype (adjusted P = 0.017; overall risk [OR] = 2.94; 95% confidence interval [CI] = 1.21-7.13) and TT/CT genotype (adjusted P = 0.020; OR = 1.95; 95% CI = 1.11-3.43) were significantly higher in lung cancer patients than that in controls. When the cases were categorized by tumor histology, the TT genotype was associated with a significantly increased risk of squamous cell carcinoma (adjusted OR = 6.53; 95% CI = 1.97-21.61; P = 0.002). Conclusion: Our findings suggest that the CD40 -1C/T SNP (rs1883832) is correlated with the susceptibility to lung cancer in Chinese, and the TT genotype may further increase the risk of lung cancer.     

Glutathione S-transferase T1-null genotype interacts synergistically with heavy smoking on lung cancer risk

We studied the influence of genotype for glutathione S-transferase T1 (GSTT1) on susceptibility to lung cancer among 184 Swedish lung cancer patients (88 never-smokers and 96 ever-smokers) and 162 matched population controls (79 never-smokers and 83 ever-smokers), with special emphasis on gene-environment interactions. Cases had significantly lower frequency of the GSTT1-null genotype than that of controls among never-smokers (4.6 vs. 16.5%, P = 0.02), whereas the frequencies were very close to each other among smokers (7.4 vs. 7.2%). Cases with high packyears of smoking, however, had a significantly higher frequency of the GSTT1-null genotype compared to that of cases with low packyears (18.3 vs. 5.6%, P = 0.005). Adjusted for age and gender, the GSTT1-null genotype appeared to be protective against lung cancer among never-smokers (odds ratio [OR] = 0.2, 95% confidence interval [CI] = 0.07-0.7), although it was associated with an increased risk for lung cancer among smokers (OR = 2.1, 95% CI = 0.8-5.9), mainly attributed to the group of heavy smokers (>23 packyears; OR = 3.5, 95% CI = 0.7-17.3). Heavy smoking conferred a threefold increased risk for lung cancer (OR = 2.6, 95% CI = 1.3-5.0) among GSTT1-positive individuals, but a ninefold increased risk when combined with the GSTT1-null genotype (OR = 9.3, 95% CI = 1.9-46.3, relative to GSTT1-positive light smokers). This joint effect was further demonstrated by a positive interaction between the GSTT1-null genotype and packyears of smoking. The risk of lung cancer increased steeply with increasing packyears among GSTT1-null smokers, whereas no such effect was seen among GSTT1-positive smokers. We conclude that the GSTT1-null genotype may strengthen the effect of heavy smoking on lung cancer risk.     

Lack of association between DNA repair gene ERCC1 polymorphism and risk of lung cancer in a Chinese population

The ERCC1 (Excision Repair Cross Complementation Group 1) gene is involved in the nucleotide excision repair pathway. This study was designed to examine whether ERCC1 Asn118Asn (G19007A) polymorphism, which has been associated with risk of some cancers among Caucasians, may be associated with risk of lung cancer in a Chinese population. ERCC1 Asn118Asn (G19007A) genotypes were determined in DNA samples from 151 cases and 143 controls. The distribution of genotypes between cases and controls was not associated with an increased risk of lung cancer (AA versus GG: adjusted OR (odds ratio) = 1.41, 95% CI (confidence interval) = 0.76-2.59; AG versus GG: adjusted OR = 0.78, 95% CI = 0.47-1.29; and AA + AG versus GG: adjusted OR = 0.93, 95% CI = 0.73-1.19). The frequency A (0.20) of the A-allele was significantly lower among these Chinese controls than in the Caucasian control populations (A = 0.54-0.65) (All P < 0.001). No statistically significant effects of age, histological subtype or smoking were found. These findings suggest that ERCC1 Asn118Asn (G19007A) polymorphism may play a limited role for lung cancer in this Chinese population.     

Genetic polymorphisms in cell cycle regulatory genes MDM2 and TP53 are associated with susceptibility to lung cancer

The tumor suppressor TP53 pathway plays a crucial role in preventing carcinogenesis through its ability to impose cell cycle arrest and apoptosis following DNA damage and oncogene activation. MDM2 is a key negative regulator of the TP53 pathway and is overexpressed in many cancers as oncoprotein. We investigated the association between genetic variation in the promoter region of MDM2 (c.-5+309G>T, rs2279744:g.G>T) and the coding region of TP53 (c.215G>C, rs1042522:g.G>C, designated Arg72Pro) and the risk of developing lung cancer. The genotypes of 1,106 patients and 1,420 controls were determined by tetra-primer amplification refractory mutation system (ARMS)-PCR or PCR-based restriction fragment length polymorphism (RFLP). Associations with risk of lung cancer were estimated by logistic regression. We observed an increased lung cancer risk associated with the MDM2 GG (odds ratio [OR] = 1.83, 95% confidence interval [CI] = 1.45-2.32) and TG (OR = 1.33, 95% CI = 1.09-1.63) genotypes. An increased risk was also associated with the TP53 Pro/Pro genotype (OR = 1.47, 95% CI = 1.17-1.85, P = 0.003) compared to the Arg/Arg genotype. The gene-gene interaction of MDM2 and TP53 polymorphisms increased lung cancer risk in a supermultiplicative manner (OR for the presence of both MDM2 GG and TP53 Pro/Pro genotypes = 4.56, 95% CI = 2.76-7.54). Significant interactions were observed between these polymorphisms (respectively and jointly) and smoking (OR = 10.41, 95% CI = 5.26-20.58) for smokers with both the MDM2 GG and TP53 Pro/Pro genotypes. In conclusion, genetic polymorphisms in cell cycle regulatory genes MDM2 and TP53 contribute to the risk of developing lung cancer.     

Association between EGFR polymorphisms and the risk of lung cancer

Target: The study aimed to investigate the role of epidermal growth factor receptor (EGFR) rs6965469 and rs763317 polymorphisms in the occurrence and development of lung cancer. Methods: We used polymerase chain reaction-ligation detection reaction (PCR-LDR) method to detect the genotypes of EGFR rs6965469 and rs763317 polymorphisms and the data were analyzed by GeneMapper software. Odds ratios (ORs) with 95% confidence intervals (CIs) was calculated by χ² test to estimate the significance difference of genotype and allele frequencies in case and control groups. ORs and 95% CIs were adjusted by logistic regression analysis with age, gender, drinking and smoking. The genotypes distributions of control group were tested by Hardy-Weinberg equilibrium (HWE). Results: The genotypes frequencies of controls for rs6965469 and rs763317 polymorphims were consistent with HWE. The distribution of rs6965469 TT genotype in two groups was significantly different (P<0.05) and TT genotype was associated with an increased risk of lung cancer (OR=6.92, 95% CI=1.33-36.00). AA genotype and A allele of rs763317 were also the susceptible factors of lung cancer. Individuals with AA genotype or A allele were more likely to suffer lung cancer (AA vs. GG: OR=7.20, 95% CI=1.33-39.07; A vs. G: OR=2.61, 95% CI=1.04-6.59). Conclusions: The EGFR rs6965469 and rs763317 polymorphisms may be risk factors for lung cancer.     

Association of interleukin-10 promoter polymorphisms with systemic lupus erythematosus

Several lines of evidence suggest interleukin-10 gene (IL-10) is a candidate gene in susceptibility to systemic lupus erythematosus (SLE). We investigated the association of IL-10 promoter single-nucleotide polymorphisms (SNPs) (-3575T/A, -2849G/A, -2763C/A, -1082A/G, -819T/C and -592A/C) and microsatellites (IL10.R, IL10.G) with SLE in 554 Hong Kong Chinese patients and 708 ethnically matched controls. Six haplotypes (hts) were identified from the SNPs. The genotype distribution of the ht1 (T-C-A-T-A), which is associated with low IL-10 production, was different in patients and controls (P=0.009). The homozygous genotype of non-ht1 was significantly increased in patients (P=0.009, odds ratio (OR)=1.80, 95% CI: 1.15-2.82). The frequency of IL10.G4 of IL10.G was also significantly increased in patients (P=0.017, OR=2.53, 95% CI: 1.18-5.40). We found that the homozygous non-ht1 combined with short allele (CA repeat number < or =21) of IL10.G has a dose-dependent effect on SLE susceptibility: non-ht1/non-ht1 with homozygous short allele showed a higher OR (OR=4.11, 95% CI: 1.27-13.2, P=0.018) of association with SLE than the genotype of non-ht1/non-ht1 with heterozygous short/long allele (OR=2.98, 95% CI: 1.26-7.07, P=0.013) and homozygous long allele (OR=1.05, 95% CI: 0.62-1.78, P=0.848). The frequency of non-ht1 was significantly increased in patients with serositis (P<0.0001, OR=2.42, 95% CI: 1.55-3.80). In conclusion, the high expression promoter genotype is associated with SLE in Chinese.     

The interleukin-10-1082 promoter polymorphism and cancer risk: a meta-analysis

Interleukin-10 (IL-10) is a multifunctional cytokine with both immunosuppressive and anti-angiogenic properties and play an important role in the pathogenesis of cancer. IL-10-1082A>G polymorphism is the most extensively studied polymorphism in the IL-10 gene in cancer susceptibility. To date, a number of case-control studies were conducted to investigate the association between IL-10-1082A>G polymorphism and cancer risk in humans. However, the association between the IL-10-1082A>G polymorphism and cancer risk is still ambiguous. In an effort to solve this controversy, we performed a meta-analysis based on 61 case-control studies, including 14,499 cancer cases and 16,967 controls. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. In the stratified analyses by specific cancer type, increased risk was found in lung cancer (OR = 3.16, 95% CI = 1.16-8.63 for GA versus AA; OR = 2.07, 95% CI = 1.16-3.70 for GG versus AA; OR = 3.17, 95% CI = 1.31-7.68 for GA/GG versus AA) and non-Hodgkin's lymphoma (OR = 1.18, 95% CI = 1.02-1.36 for GA versus AA; OR = 1.17, 95% CI = 1.02-1.35 for GA/GG versus AA). The meta-analysis also indicated that the variant genotypes were associated with a moderately increased risk in Asians in all genetic models (OR = 1.80, 95% CI = 1.17-2.76 for GA versus AA; OR = 3.32, 95% CI = 1.62-6.82 for GG versus AA; OR = 1.67, 95% CI = 1.07-2.60 for GA/GG versus AA; OR= 2.93, 95% CI = 1.43-6.03 for GG versus AA/GA). The meta-analysis suggested that the IL-10-1082A>G polymorphism was associated with increased risk of cancer in Asians and lung cancer and non-Hodgkin's lymphoma. To draw comprehensive and true conclusions, more researches with larger numbers of worldwide participants are needed to examine associations between IL-10-1082A>G polymorphism and cancer risk.     

Comprehensive assessment of P21 polymorphisms and lung cancer risk

The purpose of this study is to comprehensively evaluate potential functional polymorphisms in the P21 gene in relation to the risk of lung cancer. We first determined the frequencies of P21 polymorphisms in 27 healthy Koreans, and then examined three polymorphisms (−2266G > A, S31R, and IVS2 + 16G > C), based on their frequencies and haplotype-tagging status, in a case–control study. Individuals with at least one −2266A allele were at a significantly decreased risk of lung cancer compared with those harboring the −2266 GG genotype [adjusted odds ratio (OR) = 0.71, 95% confidence interval (CI) = 0.53–0.95, P = 0.02). The haplotypes (ht2–4) carrying 31R or IVS2 + 16C alleles were associated with a significantly decreased risk of lung cancer compared with the haplotype 31S/IVS2 + 16G, which carried wild-type alleles at both loci (adjusted OR = 0.65, 95% CI = 0.50–0.83, P = 0.007)]. When the −2266A allele and ht2–4 were considered to be protective alleles, the risk of lung cancer decreased in a dose-dependent manner as the number of protective alleles increased (P = 0.0002). These results suggest that a combined analysis of these three P21 polymorphisms might better predict the risk of lung cancer than the analysis of a single polymorphism.     

Genetic polymorphisms of TP53-binding protein 1 (TP53BP1) gene and association with breast cancer risk

In the present study, we evaluated the association between the TP53BP1 Glu353Asp and T-885G polymorphisms and breast cancer risk as well as with the clinicopathological characteristics of the patients. Genotyping of these polymorphisms was performed on 387 breast cancer patients and 252 normal and healthy women who had no history of any malignancy using PCR-RFLP method in a hospital-based Malaysian population. Breast cancer risk was not observed among women who were heterozygous (OR(adj) = 0.887; 95% CI, 0.632-1.245) or homozygous (OR(adj) = 1.083; 95% CI, 0.595-1.969) for Asp allele, and those carriers of Asp allele (OR(adj) = 0.979; 95% CI, 0.771-1.243). Similarly, women who were TG heterozygotes (OR(adj) = 1.181; 95% CI, 0.842-1.658) or GG homozygotes (OR(adj) = 1.362; 95% CI, 0.746-2.486) and carriers of G allele (OR(adj) = 1.147; 95% CI, 0.903-1.458) were not associated with increased risk of breast cancer. Asp allele genotype was significantly associated with ER negativity (p = 0.0015) and poorly differentiated tumours (p = 0.008), but G allele genotype was not associated with the clinicopathological characteristics. In conclusion, Glu353Asp and T-885G polymorphic variants might not have an influence on breast cancer risk, thus might not be potential candidates for cancer susceptibility. Glu353Asp variant might be associated with tumour aggressiveness as defined by its association with ER negativity and poorly differentiated tumours.     

Association of Rs61764370 polymorphism within let-7 microRNA-binding site with lung cancer in Iranian population

IntroductionPolymorphisms within miRNAs binding sites are associated with miRNAs function. The aim of this study was to investigate the relationship between rs61764370 polymorphism within let-7 miRNA binding site in KRAS gene and the risk of lung cancer in Iranian population.MethodsThis case-control study was conducted with 100 lung cancer patients and 100 healthy persons. The rs61764370 polymorphism was analyzed using PCR-RFLP technique and direct sequencing.ResultsWe found a significant relationship between rs61764370 (T / G) polymorphism and lung cancer risk, the GT genotype (OR: 6.25; 95% CI = 2.605–15.00; P= 0.000) and G allele (OR: 5.25; 95% CI = 2.259–12.208; P= 0.000) were significantly associated with an increased risk of lung cancer.ConclusionAccording to our findings, there is a significant relationship between the KRAS rs61764370 polymorphism and lung cancer risk in Iranian population and this polymorphism may be used as a marker in detection of lung cancer in the future.     

Meta-analysis of TNF-alpha promoter -308 A/G polymorphism and SLE susceptibility

Alleles of tumor necrosis factor-alpha (TNF-alpha) gene have been inconsistently associated with systemic lupus erythematosus (SLE), particularly the 308-A/G functional promoter polymorphism. To generate large-scale evidence on whether 308-A/G promoter polymorphism is associated with SLE susceptibility we have conducted a meta-analysis. We have identified 21 studies of this polymorphism and SLE using MEDLINE search. Meta-analysis was performed for genotypes A/A (recessive effect), A/A+A/G (dominant effect), and A allele in fixed or random effects models. All control samples were in Hardy-Weinberg proportion. The overall odds ratio (OR) of the A/A genotype was 3.2 (95% CI=2.0-5.3, P<0.001). Stratification by ethnicity indicated that the A/A genotype was associated with SLE in European-derived population (OR=4.0, CI=2.5-6.4, P<0.001). No association was detected in Asian-derived population (OR, 1.3, CI=0.3-6.3, P=0.76). The overall OR for the risk genotypes (A/A and A/G) was 2.0 (CI=1.3-3.1, P<0.001). Similar results were found between the risk allele A and SLE where a significant association was found in European population (OR=2.1, CI=1.6-2.7, P<0.001), but not in Asian (OR=1.4, CI=0.8-2.3, P=0.2) or African (OR=1.2, CI=0.6-2.5, P=0.59) populations. In summary, this meta-analysis demonstrates that the TNF-alpha promoter -308 A/G polymorphism may confer susceptibility to SLE, especially in European-derived population.     

北京地区汉族人群DNA修复基因XPD单核苷酸多态性与肺癌及食管癌风险的研究

目的：研究核苷酸切除修复基因XPD单核苷酸多态性与北京地区汉族人群肺癌及食管癌风险的关系。方法：采用以医院患者为基础的病例－对照研究方法，包括正常对照383人，肺癌患者351例，食管癌患者325例。以聚合酶链反应－限制性片段长度多态性方法分析了XPD基因Asp312 Asn和Lys751Gln多态性，比较不同基因型与肺癌及食管癌风险的关系，并探讨吸烟与基因多态交互作用对患癌风险的影响。结果：与携带312 Asp/Asp基因型者比较，携带至少1个312Asn等位基因者（即Asp/Asn和Asn/Asn基因型）罹患肺鳞癌的风险增加1．8倍（95％CI1．10－2．93），而与肺腺癌无关（校正的比值比为1．07，95％CI0．55－2．08）。分层分析显示，风险型等位基因312Asn和751Gln与吸烟有明显的交互作用。吸烟剂量≥29包／年且携带312Asn或751Gln者罹患肺鳞癌的风险最高，校正的比值比分别为12．44（95％CI4．97－31．17）和10．74（95％CI4．51－25．57）。XPD基因Asp312Asn和Lys751Gln多态与食管鳞癌风险无关。结论：XPD基因Asp312Asn和Lys751Gln多态是地区汉族人群肺鳞癌遗传易感因素，而与肺腺癌以及食管鳞癌风险无关，可能反映了不同组织学类型肺癌以及肺癌和食管癌之间的病因学差异。     

RAD51基因135G/C多态与人群发生肺癌的易感性研究

目的 探讨DNA双链断裂修复基因RAD51的5'-UTR区135G/C多态与我国人群肺癌发病的关联.方法 采用PCR-RFLP技术,检测300对肺癌病例与正常对照RAD51基因135FG/C多态位点的基因型.用SAD9.13软件进行非条件Logistic回归,校正混杂因素的影响,分析该位点变异与肺癌发病的关联.结果 病例及对照组中,皆未检测出135CC基因型.病例组135GC基因型频率显著低于对照组(26.7%比34.7%,P=0.0336).以携带GG野生基因型个体为参照,携带GC基因型能显著减少个体发生肺癌的危险性(调整优势比=0.72;95%置信区间=0.49～0.98;P=0.042).结论 RAD51的5'-UTR区135G/C多态与我国人群肺癌发病存在显著性关联,135C可能是我国人群肺癌发生的一个遗传保护因素.     

基质金属蛋白酶1基因多态性与肺癌易感性的关联研究

目的研究我国西北汉族人群基质金属蛋白酶（matrix metalloproteinase 1，MMP1）基因-1607（1G→2G）多态与肺癌发生风险的关系。方法应用聚合酶链反应-限制性片段长度多态性分析的方法，检测了150例肺癌患者和200名正常对照者删1G→2G多态的基因型，比较不同基因型与肺癌发生风险的关系。结果肺癌组2G／2G基因型频率要高于对照组（X^2=5．896，P〈0．05），2G／2G基因型者患肺癌的风险是1G／2G和1G／1G基因型的1．77倍（OR=1．77；95％CI：1．12—2．91）。吸烟者中2G／2G基因型发生肺癌的风险是1G／2G和1G／1G基因型的3．20倍（OR=3．20；95％CI：1．50～6．82）。结论我国西北汉族人群MMP1基因-1607（1G→2G）多态性与肺癌易感性有关，2G／2G基因型可以增加肺癌发生风险。