RAD51 Gene 135G/C polymorphism and the risk of four types of common cancers: a meta-analysis

RAD51 135G>C polymorphism in esophageal cancer and meta-analysis in gastrointestinal tract cancers

Background

A functional single-nucleotide polymorphism (SNP), 135G>C in the 5'UTR of the RAD51 gene, affects gene transcription activity with implications for the repair of damaged DNA related to tumorigenesis. Previous limited reported genetic studies to link the 135G>C polymorphism of RAD51 gene to the risk of gastrointestinal tract (GIT) cancers, especially esophageal cancer (EC), have been inconclusive.

Materials and Methods

The polymorphism was evaluated by RFLP-PCR in 252 EC patients and 252 healthy controls from Amritsar, Punjab, India, for case-control study. For a meta-analysis, a total of 78 studies on GIT cancers were assessed, out of which 14 eligible studies (including the present study) comprising 2842 cases and 3224 controls were included. Odds ratios (ORs) with 95% confidence intervals (CIs) and Chi-square test were used to assess the association in different inheritance models.

Results

The GC genotype (OR: 0.45, 95% CI: 0.29-0.68) and C allele (OR: 0.52, 95% CI: 0.36-0.75) were significantly lower (P = 0.0005) in cases as compared to controls. There was no significant association with any genetic model in the meta-analysis.

Conclusion

C allele provides protection for EC in the studied population contrary to previous reports in Polish, Chinese population probably due to ethic differences. Compared with previous meta-analysis on individual GIT cancers, present meta-analysis included all GIT cancers but found no association.

The Fanconi anemia pathway and Breast Cancer: A comprehensive review of clinical data

The development of breast cancer depends on several risk factors, including environmental, lifestyle and genetic factors. Despite the evolution of DNA sequencing techniques and biomarker detection, the epidemiology and mechanisms of various breast cancer susceptibility genes have not been elucidated yet. Dysregulation of the DNA damage response causes genomic instability and increases the rate of mutagenesis and the risk of carcinogenesis. The Fanconi Anemia (FA) pathway is an important component of the DNA damage response and plays a critical role in the repair of DNA interstrand crosslinks and genomic stability. The FA pathway involves 22 recognized genes and specific mutations have been identified as the underlying defect in the majority of FA patients. A thorough understanding of the function and epidemiology of these genes in breast cancer is critical for the development and implementation of individualized therapies that target unique tumor profiles. Targeted therapies (PARP inhibitors) exploiting the FA pathway gene defects have been developed and have shown promising results. This narrative review summarizes the current literature on the involvement of FA genes in sporadic and familial breast cancer with a focus on clinical data derived from large cohorts.

DNA repair pathways as guardians of the genome: Therapeutic potential and possible prognostic role in hematologic neoplasms

DNA repair pathways, which are also identified as guardians of the genome, protect cells from frequent damage that can lead to DNA breaks. The most deleterious types of damage are double-strand breaks (DSBs), which are repaired by homologous recombination (HR) and non-homologous end joining (NHEJ). Single strand breaks (SSBs) can be corrected through base excision repair (BER), nucleotide excision repair (NER), and mismatch repair (MMR). Failure to restore DNA lesions or inappropriately repaired DNA damage culminates in genomic instability and changes in the regulation of cellular functions. Intriguingly, particular mutations and translocations are accompanied by special types of leukemia. Besides, expression patterns of certain repair genes are altered in different hematologic malignancies. Moreover, analysis of mutations in key mediators of DNA damage repair (DDR) pathways, as well as investigation of their expression and function, may provide us with emerging biomarkers of response/resistance to treatment. Therefore, defective DDR pathways can offer a rational starting point for developing DNA repair-targeted drugs. In this review, we address genetic alterations and gene/protein expression changes, as well as provide an overview of DNA repair pathways.

Genetic Polymorphisms in the RAD51 Gene with a Risk of Head and Neck Cancer and Esophageal Cancer: A Meta-Analysis

Background

The role of RAD51 gene polymorphisms with the development of head and neck cancer (HNC) and esophageal cancer (EC) remains controversial. This meta-analysis was conducted to evaluate the correlation between the RAD51 polymorphisms and these two cancers quantitatively.

Methods

Databases of PubMed, Web of Science, and Embase were used to search relevant papers prior to August 17, 2019. STATA 11.0 was performed to observe the correlation.

Results

Ten relevant papers were enrolled in our analysis. Overall, a significant correlation was observed between the rs1801320 polymorphism and the increased risk of these two cancers (OR = 1.32, 95%CI = 1.03-1.71 for C vs. G; OR = 1.50, 95%CI = 1.03-2.19 for CG vs. GG; and OR = 1.44, 95%CI = 1.05-1.99 for CC+CG vs. GG). In subgroup analyses, an increased risk was found for EC (OR = 2.07, 95%CI = 1.01-4.25 for C vs. G; OR = 2.08, 95%CI = 1.17-3.71 for CC vs. GG; and OR = 1.78, 95%CI = 1.00-3.15 for CC vs. CG+GG), but not for HNC. Moreover, our analysis revealed that no statistical evidence of correlation was discovered between the polymorphism of rs1801321 and the increased risk of HNC. However, stratified analysis based on ethnicity suggested that rs1801321 polymorphism was related to the decreased risk of HNC among Caucasians (OR = 0.82, 95%CI = 0.72-0.95 for T vs. G).

Conclusions

rs1801320 polymorphism was strongly associated with the risk of these two associated cancers, especially with esophageal cancer. Moreover, our results revealed that rs1801321 polymorphism was correlated to the decreased risk of HNC among Caucasians.

Polymorphisms of 5’-UTR of rad51 gene in prostate cancer

Background. Notwithstanding that prostate cancer is largely studied all over the world for many decades, its etiology is not known and there is an intensive work to elucidate the cause and molecular markers for the development of this male cancer. Polymorphisms in DNA repairing genes may affect the DNA repairing capacity that in turn contributes to cancer development. This study aims to explore the polymorphisms of homologous recombination (HR) RAD51 gene (rs1801320 and rs1801321) as a possible risk factor for developing prostate cancer. Sequencing of 5'-UTR of RAD51 gene (rs1801320 and rs1801321) was studied in 80 DNA samples of prostate cancer and 50 DNA samples from a control group. Our results revealed a significant correlation between rs1801320 G>C polymorphism and the presence of prostate cancer in the Jordanian population (p = 0.041, X2 = 6.377). On the other hand, the rs1801321 G>T polymorphism was not associated with the presence of prostate cancer in the study population (p = 0.27, X2 = 2.6). In conclusion, our results shed a light on the possible role of RAD51 gene polymorphisms in the development of prostate cancer; however, a larger representative study is needed to elucidate a possible role of RAD51 gene polymorphisms in development and prognosis of prostate cancer.

Association between RAD51 135 G/C polymorphism and risk of 3 common gynecological cancers: A meta-analysis

AIM

Available data concerning the association between RAD51 135G/C (rs1801320) polymorphism and the risk of 3 common gynecological cancers still could not reach a consensus. Thus, we conducted a meta-analysis to explore the relationship.

METHODS

Several electronic databases and bibliographies of relevant articles were screened to identify the studies up to July 2017. Then a meta-analysis was performed to evaluate the connection between 3 common gynecological tumors' susceptibility and RAD51 135G/C polymorphism in different inheritance models. Simultaneously, we did subgroup analysis and sensitivity analysis if necessary.

RESULTS

A total of 11 articles including 14 studies involving 4097 cases and 5890 controls were included in this meta-analysis. Overall, RAD51 135G/C polymorphism increased the risk of 3 common gynecological tumors. The subgroup analysis stratified by cancer types- endometrial carcinoma (EC) and ovarian cancer (OC)-showed that RAD51 135G/C polymorphism increased the risk of EC: allele model (C vs G: odds ratio [OR] = 4.32, 95% confidence interval [CI] = 2.63-7.10, P < .00001), dominant model (CC + GC vs GG: OR = 2.28, 95% CI = 1.44-3.60, P = .004), recessive model (CC vs GC + GG: OR = 10.27, 95% CI = 14.71-22.38, P < .00001), and homozygous model (CC vs GG: OR = 7.26, 95% CI = 3.59-14.68, P < .00001), but there was no significant association between RAD51 135G/C polymorphism and OC. In the subgroup analysis stratified by source of controls, a significantly increased risk was observed in hospital-based studies. Nevertheless, the data showed RAD51 135G/C polymorphism had no link in population-based studies.

CONCLUSIONS

This meta-analysis suggested that RAD51 135G/C polymorphism was a risk factor for the three common gynecological tumors, especially for EC among hospital-based populations.

XPG Asp1104His, XRCC2 Rs3218536 A/G and RAD51 135G/C Gene Polymorphisms and Colorectal Cancer Risk: A Meta-Analysis

Background:

DNA repair mechanisms are crucial for sustaining DNA integrity and preventing carcinogenesis. The xeroderma pigmentosum group G (XPG), X-ray repair cross complementing group 2 (XRCC2) and RAD51 are candidate genes for DNA repair pathways.

Methods:

We performed a meta-analysis of 26 studies that assessed the impact of XPG Asp1104His, XRCC2 rs3218536 A/G and RAD51 135G/C polymorphisms on colorectal cancer (CRC) risk. This study included 10288 CRC patients and 11885 controls, and odds ratio (OR) with its 95% confidence interval (CI) were used to calculate the strength of association.

Results:

The results of overall meta-analysis suggested an association between the XPG Asp1104His polymorphism and CRC susceptibility in allele (OR=1.06; 95% CI=1.01-1.12) and heterozygote model (OR=1.16; 95%CI=1.02-1.31). In the subgroup analysis based on ethnicity and source of control, we found significantly increased CRC cancer risk in Asians (OR=1.12, 95%CI=1.04-1.21) and in hospital-based (OR=1.22, 95%CI=1.08-1.38) populations. Moreover, the RAD51 135 G/C polymorphism increased the risk of CRC in total using allele (OR=1.21) and recessive models (OR=1.62). However, XRCC2 rs3218536 A/G was not associated with the risk of CRC in total or in subgroups.

Conclusions:

According to the results of our meta-analysis, the XPG Asp1104His and RAD51 135 G/C polymorphisms might influence colorectal cancer risk.

The Association of Low-Penetrance Variants in DNA Repair Genes with Colorectal Cancer: A Systematic Review and Meta-Analysis

Objectives:

Approximately 35% of colorectal cancer (CRC) risk is attributable to heritable factors known hereditary syndromes, accounting for 6%. The remainder may be due to lower penetrance polymorphisms particularly of DNA repair genes. DNA repair pathways, including base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), direct reversal repair (DRR), and double-strand break repair are complex, evolutionarily conserved, and critical in carcinogenesis. Germline mutations in these genes are associated with high-penetrance CRC syndromes such as Lynch syndrome. However, the association of low-penetrance polymorphisms of DNA repair genes with CRC risk remains unclear.

Methods:

A systematic literature review of PubMed, Embase, and HuGENet databases was conducted. Pre-specified criteria determined study inclusion/exclusion. Per-allele, pooled odds ratios disclosed the risk attributed to each variant. Heterogeneity was investigated by subgroup analyses for ethnicity and tumor location; funnel plots and Egger’s test assessed publication bias.

Results:

Sixty-one polymorphisms in 26 different DNA repair genes were identified. Meta-analyses for 22 polymorphisms in 17 genes revealed that six polymorphisms were significantly associated with CRC risk within BER (APE1, PARP1), NER (ERCC5, XPC), double-strand break (RAD18), and DRR (MGMT), but none within MMR. Subgroup analyses revealed significant association of OGG1 rs1052133 with rectal cancer risk. Egger’s test revealed no publication bias.

Conclusions:

Low-penetrance polymorphisms in DNA repair genes alter susceptibility to CRC. Future studies should therefore analyze whole-genome polymorphisms and any synergistic effects on CRC risk.

Translational impact:

This knowledge may enhance CRC risk assessment and facilitate a more personalized approach to cancer prevention.

Association between a functional variant in RAD51 gene's 3' untranslated region and its mRNA expression in lymphoblastoid cell lines

Object

Variants of microRNA (miRNA)-binding sites in RAD51 gene’s 3′ untranslated region (3′UTR) are significantly associated with cancer risk, but the roles of these genetic variants in post-transcriptional regulation have not been elucidated.

Methods

The SNPs of RAD51 were identified both in the regulatory region and in the coding region by means of the online database. The bioinformatic tool SNP Function Prediction was used to predict the potential functional relevance of the miRNA-binding sites. We used additional data on RAD51 genotypes and mRNA levels available online for the genotype-phenotype association analysis.

Results

We found that rs12593359, rs7180135, rs11855560, and rs45507396 in the RAD51 3′UTR affect possible miRNA-binding sites according to bioinformatic analysis. Only rs12593359 was significantly associated with RAD51 mRNA expression in lymphoblastoid cell lines (P = 0.022).

Conclusion

This study demonstrated that rs12593359 may be a putative variant mediating the post-transcriptional regulation of the RAD51 gene. Deeper understanding of how 3′UTR variants influence RAD51 activity will pave the way to targeting of the RAD51 pathway as a cancer treatment.

Effects of Rosuvastatin and MiR-126 on Myocardial Injury Induced by Acute Myocardial Infarction in Rats: Role of Vascular Endothelial Growth Factor A (VEGF-A)

BACKGROUND The present study investigated the effects of VEGF-A targeted by miR-126 on myocardial injury after acute myocardial infarction (AMI) in rats, along with the contributions of rosuvastatin to the synergic effect. MATERIAL AND METHODS SD rats were obtained to construct AMI models by ligating their left anterior descending coronary arteries (LAD). We conducted echocardiography to check the 6 involved indexes: left ventricular ejection fractions (LVEF), fractional shortening (FS), left ventricular end-systolic volume (LVV), left ventricular end-diastolic volume (LVVd), cardiac output (CO), and heart rate (HR). Moreover, antibody sandwich enzyme-linked immunosorbent assay was carried out to determine MI markers: creatine kinase (CK), CK Isoenzyme (CK-MB), and Troponin I (cTn I). Dual-Luciferase Reporter Assay was performed to confirm the targeting of miR-126 and VEGF-A. MTT assay provided insight into the proliferation of myocardial fibroblasts. Finally, RT-RCR and Western blot were used for the detection of miR-126 and VEGF-A expressions in vivo and in vitro. RESULTS Luciferase activity assay showed that miR-126 transfection significantly decreased the relative luciferase activity in HEK293T cells when it was bound to normal 3' UTR of VEGF-A (P<0.05). In comparison to the control group, rats in the AMI model group had significantly lower LVEF, FS, and CO, and substantially higher LVVs, LVVd, HR, CK/U, CK-MB/U, and cTn-1/U (all P<0.05). Down-regulated miR-126 and up-regulated VEGF-A were also observed in MI models (P<0.05). CONCLUSIONS miR-126 and rosuvastatin have protective effects on AMI risk, and VEGF-A antagonizes effects on AMI is imposed by.

A Comprehensive Meta-Analysis of MicroRNAs for Predicting Colorectal Cancer

Colorectal cancer (CRC) has been defined as a common malignancy due to its prevailing incidence in both males and females. Recently, the intrinsic value of microRNAs (miRNAs) with respect to early cancer diagnosis has been contentious as the diagnostic accuracy of miRNAs significantly varied across different studies. As a result of this, this pioneer meta-analysis was proposed to address this issue. Qualified studies were obtained through electronic systematical searching in Medline, Embase, and PubMed. On the basis of the random-effects model, we calculated the pooled sensitivity (SEN), specificity (SPE), and area under the receiver operating characteristics curve (AUC) to assess the diagnostic accuracy of miRNAs. Subgroup analysis and meta-regression were implemented to determine how different confounding factors affect the overall diagnostic accuracy which were considered important sources of heterogeneity. All the statistical analyses were conducted with R 3.2.1 software. We incorporated 103 studies from 36 articles with a total of 3124 CRC patients and 2579 healthy individuals. MiRNAs have a good performance with the following pooled estimates: SEN = 0.769 (95% CI = 0.733-0.802), SPE = 0.806 (95% CI = 0.781-0.829), AUC = 0.857, and partial AUC = 0.773. As suggested by subgroup analyses and meta-regression, multiple miRNAs appeared to be more favorable than single miRNA (AUC: 0.918 > 0.813, partial AUC: 0.848 > 0.701, sensitivity = 0.853 > 0.718, specificity = 0.860 > 0.772). Compared with samples of plasma, blood, tissue, and feces, miRNA obtained from serum samples were more powerful for detecting CRC particularly in Asian. Our study provided exclusive evidence that multiple miRNAs extracted from serum samples had superior diagnostic performance over single miRNA for screening CRC. Therefore, this approach that is characterized by high specificity and noninvasive nature may assist in early diagnosis of CRC particularly in Asian.

RAD51 Gene 135G/C polymorphism and ovarian cancer risk: a meta-analysis

Previous studies suggest that the RAD51 gene 135G/C polymorphism could be potentially associated with the risk of ovarian cancer. However, results from observational studies are conflicting rather than conclusive. We performed a meta-analysis of the literature aiming to clarify the relationship between the polymorphism of RAD51 gene 135G/C polymorphism and the risk of ovarian cancer. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. We identified five eligible articles, 2336 ovarian cancer cases and 3548 controls. Meta-analysis results showed no significant association between 135G/C polymorphism in the RAD51 gene and ovarian cancer risk (GG vs CC: OR=0.42, 95% CI 0.16-1.06; GC vs CC: OR=0.37, 95% CI 0.12-1.16; Dominant model: OR=0.38, 95% CI 0.13-1.06; Recessive model: OR=1.20, 95% CI 0.91-1.58). No publication bias was found in the present study. This meta-analysis suggests that the RAD51 gene 135G/C polymorphism was not associated with risk of ovarian cancer. Further large and well-designed studies are needed to confirm this conclusion.

Association between RAD 51 rs1801320 and susceptibility to glioblastoma

Glioblastoma is the most common and aggressive malignant primary brain tumor. Despite decades of research and the advent of new therapies, patients with glioblastoma continue to have a very poor prognosis. Radiation therapy has a major role as adjuvant treatment for glioblastoma following surgical resection. Many studies have shown that polymorphisms of genes involved in pathways of DNA repair may affect the sensitivity of the cells to treatment. Although the role of these polymorphisms has been investigated in relation to response to radiotherapy, their role as predisposing factors to glioblastoma has not been clarified yet. In the present study, we evaluated the association between polymorphisms in DNA repair genes, namely: XRCC1 rs25487, XRCC3 rs861539 and RAD51 rs1801320, with the susceptibility to develop glioblastoma. Eighty-five glioblastoma patients and 70 matched controls were recruited for this study. Data from the 1000 Genomes Project (98 Tuscans) were also downloaded and used for the association analysis. Subjects carrying RAD51 rs1801320 GC genotype showed an increased risk of glioblastoma (GC vs GG, χ(2) = 10.75; OR 3.0087; p = 0.0010). The C allele was also significantly associated to glioblastoma (χ(2) = 8.66; OR 2.5674; p = 0.0032). Moreover, RAD51 rs1801320 C allele increased the risk to develop glioblastoma also when combined to XRCC1 rs25487 G allele and XRCC3 rs861539 C allele (χ(2) = 6.558; p = 0.0053).

Polymorphisms of homologous recombination RAD51, RAD51B, XRCC2, and XRCC3 genes and the risk of prostate cancer

Genetic polymorphisms in DNA repair genes may induce individual variations in DNA repair capacity, which may in turn contribute to the risk of cancer developing. Homologous recombination repair (HRR) plays a critical role in maintaining chromosomal integrity and protecting against carcinogenic factors. The aim of the present study was to evaluate the relationship between prostate cancer risk and the presence of single nucleotide polymorphisms (SNPs) in the genes involved in HRR, that is, RAD51 (rs1801320 and rs1801321), RAD51B (rs10483813 and rs3784099), XRCC2 (rs3218536), and XRCC3 (rs861539). Polymorphisms were analyzed by PCR-RFLP and Real-Time PCR in 101 patients with prostate adenocarcinoma and 216 age- and sex-matched controls. A significant relationship was detected between the RAD51 gene rs1801320 polymorphism and increased prostate cancer risk. Our results indicate that the RAD51 gene rs1801320 polymorphism may contribute to prostate cancer susceptibility in Poland.

Genetic 135G/C polymorphism of RAD51 gene and risk of cancer: a meta-analysis of 28,956 cases and 28,372 controls

The RAD51 gene is essential for the repair of damaged DNA related to tumor development. Although a number of genetic studies have attempted to link the 135G/C polymorphism of RAD51 gene to the risk of cancer, the results were inconclusive. The present study aimed at investigating the pooled association using the more comprehensive meta-analysis. The PubMed, EBSCO, and BIOSIS databases were searched to identify eligible studies which were published in English before March 2014. Data were extracted using standardized methods. The association was assessed by odds ratio (OR) with 95 % confidence interval (CI). Begg's test was used to measure publication bias. Sensitivity analyses were also performed to assess the stability of the results. A total of 45 eligible studies with 28,956 patients and 28,372 controls were included in this meta-analysis. Overall, significant association was detected between 135G/C polymorphism and increased cancer risk (C allele vs. G allele: OR 1.23, 95 % CI 1.18-1.28; CC vs. GG: OR 2.41, 95 % CI 2.12-2.74; CC vs. CG: OR 3.86, 95 % CI 3.41-4.37; recessive model: OR 3.57, 95 % CI 3.19-4.00). In further stratified analysis, significantly elevated cancer risk was observed among Caucasians but not Asians. Subgroup analysis by different cancers also showed their significant associations in breast cancer, hematologic malignances, ovarian cancer, colorectal cancer and endometrial cancer, but not in head and neck cancer. Our results indicated that the RAD51 135G/C polymorphism was a candidate for susceptibility of cancer. The effect of the variants on the expression levels and the possible functional role of the variants in different cancers should be addressed in further studies.

Glutathione S-transferase M1 null genotype meta-analysis on gastric cancer risk

Background

Glutathione S-transferases (GSTs) have proved to be involved in the detoxifying several carcinogens and may play an important role in carcinogenesis of cancer. Previous studies on the association between Glutathione S-transferase M1 (GSTM1) polymorphism and gastric cancer (GC) risk reported inconclusive results. To get a precise result, we conducted this present meta-analysis through pooling all eligible studies.

Methods

A comprehensive databases of Pubmed, Embase, Web of Science, and the Chinese Biomedical Database (CBM) were searched for case–control studies investigating the association between GSTM1 null genotype and GC risk. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to assess this possible association. A χ2-based Q-test was used to examine the heterogeneity assumption. Begg’s and Egger’s test were used to examine the potential publication bias. The leave-one-out sensitivity analysis was conducted to determine whether our assumptions or decisions have a major effect on the results of present work. Statistical analyses were performed with the software program STATA 12.0.

Results

A total of 47 eligible case–control studies were identified, including 6,678 cases and 12,912 controls. Our analyses suggested that GSTM1 null genotype was significantly associated with increased risk of GC (OR = 1.186, 95% CI = 1.057-1.329, P_{heterogenetiy} = 0.000, P = 0.004). Significant association was also found in Asians (OR = 1.269, 95% CI = 1.106-1.455, P_{heterogenetiy} = 0.002, P = 0.001). However, GSTM1 null genotype was not contributed to GC risk in Caucasians (OR = 1.115, 95% CI = 0.937-1.326, P_{heterogenetiy} = 0.000, P = 0.222). In the subgroup analysis stratified by sources of controls, significant association was detected in hospital-based studies (OR = 1.355, 95% CI = 1.179-1.557, P_{heterogenetiy} = 0.001, P = 0.000), while there was no significant association detected in population-based studies (OR = 1.017, 95% CI = 0.862-1.200, P_{heterogenetiy} = 0.000, P = 0.840).

Conclusion

This meta-analysis showed the evidence that GSTM1 null genotype contributed to the development of GC.

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XPC Lys939Gln polymorphism contributes to colorectal cancer susceptibility: evidence from a meta-analysis

Abstract

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Association between tumor necrosis factor-alpha gene polymorphisms and prostate cancer risk: a meta-analysis

BACKGROUND

Tumor necrosis factor-alpha (TNF-α) is an important inflammatory cytokine that may play a role in controlling the progression of prostate cancer. Two common polymorphisms in the TNF-α gene, -308G/A and -238C/T, have been suggested to alter the risk for prostate cancer, but the results have been inconclusive so far. In order to obtain a better understanding of the effects of these two polymorphisms on prostate cancer risk, all available studies were considered in a meta-analysis.

METHODS

We conducted a comprehensive literature search in the Cochrane Library, PubMed, EMBASE, Chinese Biomedical Literature database (CBM), and the China National Knowledge Infrastructure (CNKI). The associations were evaluated by calculating the pooled odds ratio (OR) with 95% confidence interval (95% CI).

RESULTS

In this meta-analysis, we included 14 studies with 5,757 patients and 6,137 control subjects for the TNF-α-308G/A polymorphism and 1,967 patients and 2,004 control subjects for the TNF-α-238C/T polymorphism. A significantly increased prostate cancer risk was found to be associated with the TNF-α-308C/T polymorphism in studies with healthy volunteers (AA + AG vs. GG: OR = 1.531, 95% CI = 1.093-2.145; P = 0.013; AG vs. GG: OR = 1.477, 95% CI = 1.047-2.085; P = 0.026). No significant association was found between the TNF-α-238G/A polymorphism and prostate cancer risk in the overall or subgroup analyses. There was no risk of publication bias in this meta-analysis.

CONCLUSIONS

Our results suggest that while the TNF-α-238G/A polymorphism may not be associated with prostate cancer the TNF-α-308C/T polymorphism may significantly contribute to prostate cancer susceptibility in healthy volunteers.

VIRTUAL SLIDES

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