Association between single nucleotide polymorphism of PD-L1 gene and non-small cell lung cancer susceptibility in a Chinese population

Associations of PD-1 and PD-L1 gene polymorphisms with cancer risk: a meta-analysis based on 50 studies

Programmed death-1 and its ligand-1 (PD-1/PD-L1), immune checkpoints proteins, play a crucial role in anti-tumor responses. A large number of studies have evaluated the relationships of PD-1/PD-L1 polymorphisms with risk of cancer, but evidence for the associations remains inconsistent. Therefore, we performed a meta-analysis to examine the associations between PD-1/PD-L1 single nucleotide polymorphisms (SNPs) and cancer predisposition. Results showed that PD-1.3 and PD-L1 rs17718883 were significantly correlated with overall cancer risk. PD-1.5 was prominently linked with cervical cancer (CC), non-small cell lung cancer (NSCLC), TC (thyroid cancer), brain tumor, AML (acute myelocytic leukemia) and UCC (urothelial cell carcinoma) risk, PD-1.9 with breast cancer (BC), AML, esophageal cancer (EC) and ovarian cancer (OC) risk, and PD-1.3 with colorectal cancer (CRC) and BCC (basal cell carcinoma) risk. PD-1.1 polymorphism slightly elevated BC and OC susceptibility, whereas the rs4143815 variant notably decreased the risk of gastric cancer (GC), hepatocellular carcinoma (HCC) and OC, but increased the risk of BC. PD-1.6 was closely linked with AML risk, PD-L1 rs2890658 with NSCLC, HCC and BC risk, rs17718883 with HCC and GC risk, rs10815225 with GC risk, and rs2297136 with NSCLC and HCC risk. Interestingly, the rs7421861, rs10815225, and rs10815225 markedly reduced cancer susceptibility among Asians. The rs7421861 polymrophism decreased cancer risk among Caucasians, rather than the rs10815225 elevated cancer risk. Our results supported that PD-1 and PD-L1 SNPs were dramatically correlated with cancer risk.

The Relationship Between PD-1(rs2227981) and PD-L1(rs2890658) Polymorphisms and Urothelial Cell Carcinoma

Background Urothelial cell carcinoma, which is believed to develop from the urothelium (transitional epithelium), is the most common aggressive tumor and accounts for the ten most prevalent cancers in the world. The risk factors for urothelial cell carcinoma are aging, smoking, gender, and genetic alternations. Programmed cell death1 (PD-1) has been widely described as a negative regulator of T-cells by sending inhibitory signals to the T-cell. Through PD-1 binding with PD-L1 (ligand for PD-1), an inhibitory signal is propagated to the T cell. The polymorphisms of PD-1 and PD-L1 lead to an efficient T-cell response and affect an anti-tumor reaction. The polymorphisms of PD-1 and PD-L1 could also affect the carcinogenesis of human cancer, including urothelial cell carcinoma. Therefore, in this study, we evaluated the relation between PD-1(rs2227981) and PD-L1(rs2890658) polymorphisms and the carcinogenesis of urothelial cell carcinoma. Materials and methods This study was conducted using 211 healthy controls and 256 cases of urothelial cell carcinoma among the Japanese population. The DNA samples were extracted from the peripheral white blood cells of each subject. The genotype was detected by using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method. Results C/T (Adjusted OR 1.55, 95% CI:1.02-2.35) and C/T+T/T (OR 1.46, 95% CI:1.01-2.12) genotypes of PD-1 rs2227981 were significant and risk factors for urothelial cancer. Male with A/A genotype in PD-L1 and CT genotype in PD-1 has a significant higher risk factor compared with other genotypes (Adjusted OR 1.83, 95% CI:1.05-3.21). Conclusions and discussion We found that C/T(PD-1) and "A/A (PD-L1) and C/T(PD-1)" were predominant in urothelial cell carcinoma cases. This indicates that C/T(PD-1) and "A/A (PD-L1) and C/T(PD-1)" genotypes could increase susceptibility to urothelial cell carcinoma. However, since our findings indicated that the effects of PD-1 and PD-L1 polymorphisms included discrepancies, additional research will be needed to evaluate the relationship between human cancer and PD-1 and PD-L1 polymorphisms. This is the first study that seeks to find the relation between PD-1(rs2227981) and PD-L1(rs2890658) polymorphisms concerning urothelial cell carcinoma among the Japanese population.

PD-L1 rs2890658 Polymorphism Increases Risk for Non-Small-Cell Lung Cancer in Northern China Population Based on Experimental Data and Meta-Analysis

Purpose

To dig the PD-L1 rs2890658 polymorphism with susceptibility of non-small-cell lung cancer (NSCLC) in northern China.

Patients and Methods

There were 600 NSCLC patients and 600 age and sex matched controls from the same ethnic origin recruited in the present research. Polymerase chain reaction-restriction fragment length polymorphism method genotyped PD-L1 rs2890658 polymorphism. PubMed and Embase were searched to get eligible literature for meta-analysis. The association between PD-L1 rs2890658 polymorphism and NSCLC risk was calculated with odds ratio and 95% confidence interval.

Results

It is more likely that individuals who have CC genotype and C allele are 2.15 and 1.41 times to develop NSCLC compared with individuals with AA genotype and A allele, respectively. Meta-analysis showed that the individuals who have C allele and CA genotype increased the risk of suffering from NSCLC.

Conclusion

PD-L1 rs2890658 polymorphism increased NSCLC risk in northern China population and it might predict the occurrence of NSCLC.

Programmed Death Ligand 2 Gene Polymorphisms Are Associated With Lung Adenocarcinoma Risk in Female Never-Smokers

Objectives

Lung cancer in never-smokers is a distinct disease associated with a different genomic landscape, pathogenesis, risk factors, and immune checkpoint inhibitor responses compared to those observed in smokers. This study aimed to identify novel single nucleotide polymorphisms (SNPs) of programmed death-1 (encoded by PDCD1) and its ligands, programmed death ligand 1 (CD274) and 2 (PDCD1LG2), associated with lung cancer risk in never-smoking women.

Materials and Methods

During September 2002 and July 2012, we enrolled never-smoking female patients with lung adenocarcinoma (LUAD) (n=1153) and healthy women (n=1022) from six tertiary hospitals in Taiwan. SNP data were obtained and analyzed from the genome-wide association study dataset and through an imputation method. The expression quantitative trait loci (eQTL) analysis was performed in both tumor and non-tumor tissues for the correlation between genetic expression and identified SNPs.

Results

A total of 12 PDCD1LG2 SNPs related to LUAD risk were identified in never-smoking women, including rs2381282, rs4742103, rs4237162, rs4742104, rs12237624, rs78096119, rs6476988, rs7857315, rs10975178, rs7854413, rs56001683, and rs7858319. Among them, six tagged PDCD1LG2 SNPs rs2381282, rs4742103, rs4237162, rs4742104, rs78096119, and rs56001683 were significantly associated with LUAD risk. Specifically, two PDCD1LG2 SNPs, rs12237624 and rs78096119, were associated with previous pulmonary tuberculosis infection in relation to LUAD susceptibility. Through an eQTL assay, we found that rs2381282 (p < 0.001), rs12237624 (p = 0.019), and rs78096119 (p = 0.019) were associated with the expression levels of programed death ligand 2.

Conclusions

Novel SNPs of programed death ligand 2 associated with lung adenocarcinoma risk were identified. Among them, two SNPs were associated with pulmonary tuberculosis infection in relation to lung adenocarcinoma susceptibility. These SNPs may help to stratify high-risk populations of never-smokers during lung cancer screening.

Relationship of Programmed Death-1 (PD-1) and Programmed Death Ligand-1 (PD-L1) Polymorphisms with Overall Cancer Susceptibility: An Updated Meta-Analysis of 28 Studies with 60 612 Subjects

Background

Programmed death-1 and its ligand-1 (PD-1/PD-L1) regulate tumor immunotherapy. A large number of studies have explored the relationship between PD-1, PD-L1, and different tumor susceptibility. However, these conclusions are not always consistent. Therefore, we updated this meta-analysis.

Material/Methods

MEDLINE, Web of Science, EMBASE and other databases were searched systematically to obtain related research. Then, we used STATA15.0 software to carry out the final meta-analysis. The computational advantage is better than OR to evaluate this relationship.

Results

A total of a total of 28 related studies were involved in our meta-analysis. It was found that PD-1 rs11568821 and rs7421861 increased the overall cancer probability in the allelic genetic model, while PD-1 rs36084323 effectively reduced the risk of cancer in the dominant genetic model. In the homozygous genetic model, PD-L1 rs17718883 effectively increased the probability of tumorigenesis. PD-L1rs4143815 is associated with a reduced incidence of cancer in heterozygote, homozygote and dominant genetic patterns. Subgroup analysis showed that PD-1rs2227981 can promote the susceptibility to breast cancer, while PD-1rs2227982 can reduce the susceptibility to breast cancer. PD-L1 rs2890658 can significantly reduce the risk of lung and liver cancer.

Conclusions

PD-1rs11568821, rs36084323, rs7421861, pD-L1rs17718883, and rs4143815 are associated with tumor susceptibility. However, a review based on more experimental evidence is needed to verify our findings.

Impact of copy number variant and single nucleotide polymorphism of the programmed death-ligand 1 gene, programmed death-ligand 1 protein expression and therapy regimens on overall survival in a large group of Caucasian patients with non-small cell lung carcinoma

Anti-programmed death-1 or anti-programmed death-ligand 1 (PD-L1) blockade may be ineffective in some patients with non-small cell lung cancer (NSCLC) with high percentage of tumor cells with PD-L1 expression. In addition, immunotherapy may provide great benefits in patients without PD-L1 expression. The present study assessed PD-L1 protein expression by immunohistochemistry, copy number variation (CNV) of PD-L1 and two single nucleotide polymorphisms (SNPs), rs822335 and rs822336, in the promoter of PD-L1 by quantitative PCR in 673 patients with NSCLC. Overall survival time of patients with NSCLC depending on the assessed predictive factors (PD-L1 CNV or SNP) and the treatment methods (immunotherapy in first/second line of treatment or chemotherapy) was analyzed. The present study revealed significantly higher PD-L1 copies number in patients with ≥10% and ≥50% of tumor cells with PD-L1 expression compared to patients with lower percentage of PD-L1-positive tumor cells (P=0.02 and P=0.0002, respectively). There was a significant positive correlation (R=0.2; P=0.01) between number of PD-L1 copies and percentage of tumor cells with PD-L1 protein expression. Percentage of tumor cells with PD-L1 expression was lower in patients with TT genotype of the rs822335 polymorphism compared to those with CC genotype (P=0.03). The present study observed significantly higher risk of death in patients treated with chemotherapy compared to those treated with immunotherapy (P<0.0001; hazard ratio=2.4768; 95% confidence interval, 2.0120–3.0490). The present study demonstrated a close relationship between PD-L1 copies number, genotype of rs822335 PD-L1 polymorphism and PD-L1 protein expression on tumor cells. However, the impact of CNV and SNPs of PD-L1 on overall survival of patients with NSCLC requires further investigation.

Immune Checkpoint Molecules-Inherited Variations as Markers for Cancer Risk

In recent years, immunotherapy has been revolutionized by a new approach that works by blocking receptors called immune checkpoints (IC). These molecules play a key role in maintaining immune homeostasis, mainly by suppressing the immune response and by preventing its overactivation. Since inhibition of the immune response by IC can be used by cancer to avoid recognition and destruction by immune system, blocking them enhances the anti-tumor response. This therapeutic approach has brought spectacular clinical effects. The ICs present heterogeneous expression patterns on immune cells, which may affect the effectiveness of immunotherapy. The inherited genetic variants in regulatory regions of ICs genes can be considered as potential factors responsible for observed inter-individual differences in ICs expression levels on immune cells. Additionally, polymorphism located in exons may introduce changes to ICs amino acid sequences with potential impact on functional properties of these molecules. Since genetic variants may affect both expression and structure of ICs, they are considered as risk factors of cancer development. Inherited genetic markers such as SNPs may also be useful in stratification patients into groups which will benefit from particular immunotherapy. In this review, we have comprehensively summarized the current understanding of the relationship between inherited variations of CTLA-4, PDCD1, PD-L1, BTLA, TIM-3, and LAG-3 genes in order to select SNPs which can be used as predictive biomarkers in personalized evaluation of cancer risk development and outcomes as well as possible response to immunotherapy.

Evaluating the Possible Association between PD-1 (Rs11568821, Rs2227981, Rs2227982) and PD-L1 (Rs4143815, Rs2890658) Polymorphisms and Susceptibility to Breast Cancer in a Sample of Southeast Iranian Women

INTRODUCTION

Programmed cell death-1 (PD-1) and its ligands (PD-L1 and PD-L2) play a critical role as a  regulator of immune-system cells, including T cell, natural killer T (NKT), monocytes, dendritic cells (DC), and B cells.

OBJECTIVE

This study aimed to find a possible association between PD-1 (rs11568821, rs2227981, rs2227982), and PD-L1 (rs4143815, rs2890658) variants and Breast Cancer (BC) risk in a sample of southeast Iranian women.

METHOD

The case-control study consisted of 520 individuals, including 260 histologically confirmed BC patients and 260 non-cancer age-matching healthy women as the control group. The Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Tetra-Primer Amplification Refractory Mutation System-Polymerase Chain Reaction (T-ARMS-PCR) methods were used for genotyping of PD-1 (rs11568821, rs2227981, rs2227982), and PD-L1 (rs4143815, rs2890658) polymorphisms.

RESULTS AND CONCLUSION

Our findings indicated that the PD-L1 rs4143815 (G/C) variant meaningfully reduced the risk of BC. However, the PD-L1 rs2890658 variant increased the BC risk in the AC genotype as well as the A allele. Furthermore, we could not find a meaningful association between PD-1 rs11568821, PD-1 rs2227981, PD-1 rs2227982, and BC. Our team examined the possible association between variants and clinicopathological characteristics, including age, size of tumour, lymph node, histology, grade of tumour, estrogen and progesterone receptors status as well as human growth factor receptor 2 (HER2). Our findings demonstrated that PD-L1 rs4143815, PD-L1 rs2890658, PD-1 rs2227982 had a significant association with age. Additionally, we found a significant relation between PD-1 rs2227982 variant and tumour size. Statistical analyzes of PD-1 rs2227981 and PD-1 rs11568821 variants showed a meaningful relation between tumour grade and tumour stage (p=0.006), respectively.<br />.

The role of genetic polymorphism within PD-L1 gene in cancer. Review

The maintenance of homeostasis of the immune system depends on the balance between excitatory and inhibitory signals. Programmed death ligand (PD-L1) is a molecule which downregulates the immune system targeting the programmed death receptor 1 (PD-1). Under physiological conditions, the receptor is constitutively expressed in lymphocytes. The PD-L1 / PD-1 pathway plays a key role in completing the immune response in the right way, preventing excessive stimulation of the cells of the immune system, protecting the organism against autoimmunity. Under pathological conditions PD-L1 expression may take place in tumor cells. Binding of PD-1 to its ligand on tumor cells suppresses T lymphocytes through a negative feedback. This mechanism allows abnormal cells to avoid destruction by the host immune system. The expression of PD-L1 in tumors has been described in many histological types of cancer: melanoma, lung cancer, breast and ovarian, pancreatic and esophagus adenocarcinoma, kidney tumors and bladder cancers as well as in hematopoietic malignancies. Many studies report a significant effect of PD-L1 polymorphisms on clinical parameters of patients. Studies of PD-L1 polymorphisms showed their influence on the stage of cancer, effectiveness of chemotherapy and prognosis after tumor resection. Further analysis of the polymorphisms may result in development of effective therapies that restore anti-tumor immunity. Inhibition of PD-L1 / PD-1 is one of the most promising immunotherapies for various types of cancer. This work was intended to present information about the impact of PD-L1 gene expression and polymorphisms on the clinical parameters of patients with cancer.

Association between PD-1 and PD-L1 Polymorphisms and the Risk of Cancer: A Meta-Analysis of Case-Control Studies

A number of case-control studies regarding the association of the polymorphisms in the programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) genes with the risk of cancer have yielded inconsistent findings. Therefore, we have conducted a comprehensive, updated meta-analysis study to identify the impact of PD-1 and PD-L1 polymorphisms on overall cancer susceptibility. The findings revealed that PD-1 rs2227981 and rs11568821 polymorphisms significantly decreased the overall cancer risk (Odds Ratio (OR) = 0.82, 95% CI = 0.68–0.99, p = 0.04, TT vs. CT+CC; OR = 0.79, 95% CI = 0.67–0.94, p = 0.006, AG vs. GG, and OR = 0.82, 95% CI = 0.70–0.96, p = 0.020, AG+AA vs. GG, respectively), while PD-1 rs7421861 polymorphism significantly increased the risk of developing cancer (OR = 1.16, 95% CI = 1.02–1.33, p = 0.03, CT vs. TT). The PD-L1 rs4143815 variant significantly decreased the risk of cancer in homozygous (OR = 0.62, 95% CI = 0.41–0.94, p = 0.02), dominant (OR = 0.70, 95% CI = 0.50–0.97, p = 0.03), recessive (OR = 0.76, 95% CI = 0.60–0.96, p = 0.02), and allele (OR = 0.78, 95% CI = 0.63–0.96, p = 0.02) genetic models. No significant association between rs2227982, rs36084323, rs10204525, and rs2890658 polymorphisms and overall cancer risk has been found. In conclusions, the results of this meta-analysis have revealed an association between PD-1 rs2227981, rs11568821, rs7421861, as well as PD-L1 rs4143815 polymorphisms and overall cancer susceptibility.

PD-L1 gene copy number and promoter polymorphisms regulate PD-L1 expression in tumor cells of non-small cell lung cancer patients

Most drugs targeting PD-1 or PD-L1 are more effective when cancer cells of non-small cell lung cancer (NSCLC) patients express PD-L1 protein. The polymorphisms of PD-L1 gene and PD-L1 gene copy number could be responsible for PD-L1 mRNA and protein expression. We analyzed PD-L1 protein expression using two IHC assays, mRNA (PD-L1) expression by qRT-PCR, PD-L1 gene promoter region polymorphisms (rs822335 and rs822336) by qPCR and PD-L1 gene copy number by fluorescence in situ hybridization method. Patients with CC genotype in rs822335 had significantly (p = 0.043) higher percentage of tumor cells with PD-L1 expression (test with 22C3 antibody) than patients with CT or TT genotypes. PD-L1 gene copy number significantly positively correlated with percentage of tumor cells with PD-L1 expression detected in tests with 22C3 antibody (p = 0.005, R = +0.442) and with SP142 antibody (p = 0.021, R = +0.369). PD-L1 gene copy number did not correlate with PD-L1 mRNA expression. Patients with PD-L1 expression tested with 22C3 antibody had significantly higher expression of PD-L1 mRNA (p = 0.023), number of chromsosme 9 centromeres (p = 0.023) and PD-L1 gene copy number (p = 0.003) than patients without PD-L1 expression on tumor cells PD-L1 gene polymorphisms and PD-L1 gene copy number may be a predictor for PD-L1 protein expression on tumor cells.

Association of PD-L1 gene rs4143815 C>G polymorphism and human cancer susceptibility: A systematic review and meta-analysis

Programmed death ligand 1(PD-L1) mediated immune escape play important roles in the development of cancer. The gene polymorphism of PD-L1, in particular rs4143815 C > G, has been associated with the cancer risks, but with conflicting results. Therefore, this meta-analysis was aimed to assess the association between rs4143815 C > G and cancer susceptibility. A systematic literature search was performed to select the studies and the pooled odds ratio (OR) with 95% confidence interval (CI) was used to evaluate the strength of association. Eleven eligible studies containing 3711 cases and 3704 controls were enrolled in the meta-analysis. The results suggested that there is a strong association between rs4143815 C > G and the cancer risks (G vs. C: OR = 1.386, 95% CI: 1.132-1.696, p = 0.002; GG vs. CG + CC: OR = 1.843 95% CI: 1.300-2.613, p = 0.002; GG + CG vs. CC: OR = 1.280, 95% CI: 1.040-1.576, p = 0.020). Subgroup analysis based on cancer type suggested that PD-L1 rs4143815 C > G might increase the susceptibility to gastric cancer (G vs. C: OR = 1.842, 95% CI: 1.403-2.418, p < 0.001) and bladder cancer (G vs. C: OR = 2.015, 95% CI: 1.556-2.608, p < 0.001), and genotype GG carriers of PD-L1 rs4143815 C > G might have higher risks of HCC (GG vs. CG + CC: OR = 2.226 95% CI: 1.562-3.172, p < 0.001). PD-L1 rs4143815 C > G might confer an increased cancer risk, indicating this SNP may contribute to the pathogenesis of cancer and might be used as a potential biomarker to predict the susceptibility to cancer.

PD-1 and cancer: molecular mechanisms and polymorphisms

The programmed cell death protein 1 (PD-1) is expressed by activated T cells that act as an immunoregulatory molecule, and are responsible for the negative regulation of T cell activation and peripheral tolerance. The PD-1 gene also encodes an inhibitory cell surface receptor involved in the regulation of T cell functions during immune responses/tolerance. Beyond potent inhibitory effects on T cells, PD-1 also has a role in regulating B cell and monocyte responses. An overexpression of PD-1 has been reported to contribute to immune system avoidance in different cancers. In particular, PD-1 over-expression influences tumor-specific T cell immunity in a cancer microenvironment. Blocking the PD-1/PD-1 ligand (PD-L1) pathway could potentially augment endogenous antitumor responses. Along these lines, the use of PD-1/PD-L1 inhibitors has been applied in clinical trials against diverse forms of cancer. It was believed that antibodies targeting PD-1/PD-L1 might synergize with other treatments that enhance endogenous antitumor immunity by blocking inhibitory receptor-ligand interactions. However, in all cases, the host genetic status (as well as that of the tumor) is likely to have an impact on the expected outcomes. Various investigations have evaluated the association between PD-1 polymorphisms and the risk of various types of cancer. Frequently studied PD-1 polymorphisms, PD-1.1 (rs36084323), PD-1.3 (rs11568821), PD-1.5 (rs2227981), PD-1.9 (rs2227982), and PD-1 rs7421861, and their associations in the risk of susceptibility to different types of cancer are mentioned in this review, as are studies highlighting the significance of conducting genetic association studies in different ethnic populations.

PD-L1 Gene Polymorphism and High Level of Plasma Soluble Pd-L1 Protein may be aSsociated with Non-Small Cell Lung Cancer

Background

PD-1 and its ligand PD-L1 belong to the co-inhibition molecules, which can downregulate immune responses. The PD-L1 polymorphism and the level of soluble PD-L1 (sPD-L1) were investigated in non-small cell lung cancer (NSCLC).

Methods

A total of 288 NSCLC patients and 300 controls were enrolled. An A/C polymorphism at position 8923 in the PD-L1 gene was genotyped using the polymerase chain reaction-restriction fragment length polymorphism method.

Results

The prevalence of the 8923C allele was significantly higher in NSCLC patients than controls (10.2% versus 5.3%, p = 0.002, odds ratio 2.03, 95% confidence interval 1.30-3.17; data were adjusted for age and sex). NSCLC patients also showed increased plasma levels of sPD-L1 compared to controls (1.92 ng/mL versus 0.91 ng/mL, p<0.001). Furthermore, lung adenocarcinoma patients had higher sPD-L1 levels than patients with squamous cell carcinoma (p<0.01). However, no association was observed between the different genetic variants and plasma concentrations of sPD-L1.

Conclusions

The PD-L1 8923A/C polymorphism could be associated with increased susceptibility to NSCLC. Plasma levels of sPD-L1 are significantly increased in NSCLC patients, especially those with adenocarcinoma.

The role of PD-1 and PD-L1 in T-cell immune suppression in patients with hematological malignancies

T-cell activation and dysfunction relies on direct and modulated receptors. Based on their functional outcome, co-signaling molecules can be divided as co-stimulators and co-inhibitors, which positively and negatively control the priming, growth, differentiation and functional maturation of a T-cell response. We are beginning to understand the power of co-inhibitors in the context of lymphocyte homeostasis and the pathogenesis of leukemia, which involves several newly described co-inhibitory pathways, including the programmed death-1 (PD-1) and PD-1 ligand (PD-L1) pathway. The aim of this review is to summarize the PD-1 and PD-L1 biological functions and their alterative expression in hematological malignancies. The role of PD-1 and PD-L1 in T-cell immune suppression and the potential for immunotherapy via blocking PD-1 and PD-L1 in hematological malignancies are also reviewed.

A meta-analysis of the relationship between glutathione S-transferase T1 null/presence gene polymorphism and the risk of lung cancer including 31802 subjects

The relationship between glutathione S-transferase T1 (GSTT1) null/presence gene polymorphism and the risk of lung cancer from the published reports are still conflicting. This study was conducted to evaluate the relationship between GSTT1 null/presence gene polymorphism and the risk of lung cancer using meta-analysis method. The association studies were identified from PubMed, and Cochrane Library on July 1, 2012, and eligible investigations were included and synthesized using meta-analysis method. 51 reports were recruited into this meta-analysis for the association of null genotype of GSTT1 with lung cancer susceptibility, consisting of 15,140 patients with lung cancer and 16,662 controls. There was a marked association between GSTT1 null genotype and lung cancer risk in overall populations (OR = 1.15, 95 % CI 1.04-1.27, P = 0.007). Furthermore, GSTT1 null genotype was associated with the lung cancer risk in Asians (OR = 1.47, 95 % CI 1.23-1.76, P < 0.0001). However, GSTT1 null genotype was not associated with the risk of lung cancer in Caucasians, Brazilian population and Africans. In conclusion, GSTT1 null genotype is associated with the lung cancer in overall populations and in Asians.