Associations between polymorphisms in folate-metabolizing genes and pancreatic cancer risk in Japanese subjects

Exploring Disparities in Pancreatic Ductal Adenocarcinoma Outcomes among Asian and Pacific Islander Subgroups

Pancreatic ductal adenocarcinoma (PDAC) is a challenging malignancy with known disparities in outcomes across ethnicities. Studies specifically investigating PDAC in Asian populations are sparse, overlooking the rich diversity within this group. This research seeks to fill that gap by examining survival differences across the broad spectrum of Asian ethnicities, acknowledging the complexity and varied experiences within these communities. Utilizing the National Cancer Database from 2004 to 2019, we categorized patients into East Asian, Southeast Asian, South Asian, and Pacific Islander groups. Non-Asians or Pacific Islanders were excluded. Overall survival was analyzed using a Cox hazards model. The study consisted of 13,254 patients. Most patients were East Asian (59.4%, n = 7,866). Southeast Asians exhibited the poorest survival in unadjusted analysis (HR, 1.32; 95% confidence interval, 1.23-1.42; P < 0.001) compared with South Asians who exhibited the best survival. Multivariable analysis revealed significantly worse survival for East Asians and Pacific Islanders relative to South Asians, whereas Southeast Asians' results were not significantly different. Asian subgroup differences notably affect PDAC outcomes. Research on genetic and cultural aspects, especially in Southeast Asians, and tackling health disparities are crucial for enhancing survival in this diverse disease.

SIGNIFICANCE

This study highlights the significant survival disparities among Asian subgroups with pancreatic cancer, utilizing a large national database. By differentiating among East Asian, Southeast Asian, South Asian, and Pacific Islander groups, it underscores the need for tailored research and healthcare approaches. Addressing these differences is essential for developing culturally sensitive interventions and potentially improving outcomes in a disease that uniquely affects these diverse populations.

Influence of MTHFR polymorphism, alone or in combination with smoking and alcohol consumption, on cancer susceptibility

5,10-methylenetetrahydrofolate reductase (MTHFR) mutations play a significant role in various types of cancers, serving as crucial regulators of folate levels in this process. Several studies have examined the effects of smoking and drinking on MTHFR-related cancers, yielding inconsistent results. Therefore, the objective of this study was to evaluate the magnitude of the effects of gene-smoking or gene-drinking interactions on cancer development. We conducted a comprehensive literature search in PubMed, Web of Science, CNKI, and Wan Fang databases up until May 10th, 2022, to identify relevant articles that met our inclusion criteria. The extracted data from these studies were used to calculate the overall odds ratio (OR) and corresponding 95% confidence interval (95% CI) using either a fixed-effect or random-effect model in Stata version 11.2. Stratified analyses were performed based on ethnicity, control group origin, and cancer classification to assess the risk of cancers associated with gene-smoking or gene-drinking interactions. Sensitivity analyses were conducted to investigate potential sources of heterogeneity, and publication bias was assessed using the Begg's test and Egger's test. Additionally, regression analysis was employed to explore the influence of relevant variables on heterogeneity. To evaluate the statistical correlations, analytical methods such as the false-positive report probability and the Bayesian false discovery probability were applied to assess the reliability of the findings. In our meta-analysis, a total of 47 articles were included, comprising 13,701 cases and 21,995 controls for the C677T polymorphism and 5,149 cases and 8,450 controls for the A1298C polymorphism. The results indicated a significant association between C677T polymorphism and cancer risks when combined with smoking (CT + TT vs CC, OR [95% CI] = 1.225 [1.009-1.487], p = 0.041). Stratified analysis further revealed a significant increase in liver cancer risk for individuals with the C677T when combined with smoking (liver cancer: CT + TT vs CC, OR [95% CI] = 1.564 [1.014-2.413], p = 0.043), particularly among Asian smokers (CT + TT vs CC, OR [95% CI] = 1.292 [1.007-1.658], p = 0.044). Regarding the A1298C polymorphism, an elevated risk of cancer was observed in mixed populations alone (CC + AC vs AA, OR [95% CI] = 1.609 [1.087-2.381], p = 0.018), as well as when combined with smoking (CC + AC vs AA, OR [95% CI] = 1.531 [1.127-2.080], p = 0.006). In non-drinkers, C677T polymorphism was found to be associated with esophageal cancer risk (C677T: CT + TT vs CC, OR [95% CI] = 1.544 [1.011-2.359], p = 0.044) and colon cancer risk (CC + AC vs AA, OR [95% CI] = 1.877 [1.166-3.054], p = 0.010), but there was no clear link between this polymorphism and cancer risk among drinkers. The association between the C677T polymorphism and cancer risk among smokers was found to be significant, suggesting that the combination of tobacco and the C677T polymorphism may enhance the carcinogenic process, particularly in liver cancer. However, no similar relationship was observed for the A1298C polymorphism. Interestingly, significantly increased cancer risk was observed in individuals with C677T genetic variants who were nondrinkers, but not among drinkers. These findings highlight the potential role of the C677T polymorphism in modifying cancer risk in specific contexts, such as smoking and alcohol consumption.

The relationship between methionine synthase rs1805087 polymorphism and hematological cancers risk

Background: The relationship between hematological cancer susceptibility and methionine synthase MTR A2756G (rs1805087) polymorphism is inconclusive based on data from past studies. Hence, this updated meta-analysis was conducted to investigate the relationship between methionine synthase reductase (MTR) rs1805087 polymorphism and hematological cancers. Method: We searched EMBASE, Google Scholar, Ovid and PubMed databases for possible relevant articles up to December 31, 2019. Results: The overall pooled outcome of our analysis showed lack of association between the risk of hematological malignancies and MTR A2756G polymorphism under the allele model (G vs A: odds ratio = 1.001, 95% CI: 0.944-1.061; p = 0.983), recessive model (GG vs GA + AA: odds ratio = 1.050, 95% CI: 0.942-1.170; p = 0.382). Conclusion: The findings in this study demonstrate a lack of relationship between hematological cancers and MTR A2756G.

Computational Prediction of Probable Single Nucleotide Polymorphism-Cancer Relationships

Genetic variations such as single nucleotide polymorphisms (SNPs) can cause susceptibility to cancer. Although thousands of genetic variants have been identified to be associated with different cancers, the molecular mechanisms of cancer remain unknown. There is not a particular dataset of relationships between cancer and SNPs, as a bipartite network, for computational analysis and prediction. Link prediction as a computational graph analysis method can help us to gain new insight into the network. In this article, after creating a network between cancer and SNPs using SNPedia and Cancer Research UK databases, we evaluated the computational link prediction methods to foresee new SNP-Cancer relationships. Results show that among the popular scoring methods based on network topology, for relation prediction, the preferential attachment (PA) algorithm is the most robust method according to computational and experimental evidence, and some of its computational predictions are corroborated in recent publications. According to the PA predictions, rs1801394-Non-small cell lung cancer, rs4880-Non-small cell lung cancer, and rs1805794-Colorectal cancer are some of the best probable SNP-Cancer associations that have not yet been mentioned in any published article, and they are the most probable candidates for additional laboratory and validation studies. Also, it is feasible to improve the predicting algorithms to produce new predictions in the future.

Association of MTHFR gene polymorphisms with pancreatic cancer: meta-analysis of 17 case-control studies

BACKGROUND

Pancreatic cancer (PC) is a seriously malignant tumor with a low 5-year survival rate. The relationship between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and PC has been reported by several studies. However, the results were controversial. Thus, we conducted a meta-analysis to summarize available data on MTHFR gene and PC.

METHODS

We searched PubMed, Embase, Web of Science, Wanfang, CNKI databases prior to July 2019. Data were analyzed by RevMan 5.3 and STATA 12.0 software. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the strength of the association. Subgroup analysis, sensitivity analysis and assessment of publication bias were performed in this study.

RESULTS

Ten articles with 17 reports (10 for C677T, 7 for A1298C) were eligible for inclusion in the meta-analysis (1864 cases and 3165 controls for C677T, and 1488 cases and 1946 controls for A1298C). Our meta-analysis detected that C677T was associated with PC for three genetic models (allele model: OR = 1.24, 95% CI: 1.00-1.53, P = 0.047; recessive model: OR = 1.39, 95% CI: 1.04-1.86, P = 0.027; homozygous model: OR = 1.60, 95% CI: 1.04-2.45, P = 0.034). In the stratified analyses according to ethnicity, source of controls and genotyping method, significant association was observed in genotyping method subgroup. For the A1298C polymorphism, no significant association was observed either in overall analysis or in subgroup analysis under all genetic models.

CONCLUSIONS

MTHFR gene C677T rather than A1298C polymorphism may be associated with PC. Larger sample size studies should be performed to find the association between MTHFR gene and PC.

Methionine synthase A2756G polymorphism influences pediatric acute lymphoblastic leukemia risk: a meta-analysis

Plenty of studies have investigated the effect of methionine synthase (MTR) A2756G polymorphism on risk of developing pediatric acute lymphoblastic leukemia (ALL), but the available results were inconsistent. Therefore, a meta-analysis was conducted to derive a more precise estimation of the association between MTR A2756G polymorphism and genetic susceptibility to pediatric ALL. The PubMed, Embase, Google Scholar, Web of Science, ScienceDirect, Wanfang Databases and China National Knowledge Infrastructure were systematically searched to identify all the previous published studies exploring the relationship between MTR A2756G polymorphism and pediatric ALL risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were applied to evaluate the strength of association. Sensitivity analysis and publication bias were also systematically assessed. This meta-analysis finally included ten available studies with 3224 ALL cases and 4077 matched controls. The results showed that there was significant association between MTR A2756G polymorphism and risk of pediatric ALL in overall population (AG vs. AA: OR = 1.13, 95%CI = 1.02-1.26, P = 0.02; AG+GG vs. AA: OR = 1.13, 95%CI = 1.02-1.25, P = 0.01; G allele vs. A allele: OR = 1.10, 95%CI = 1.01-1.20, P = 0.03). In the stratification analyses by ethnicity, quality score and control source, significant association was found in Caucasians, population-based designed studies and studies assigned as high quality. In conclusion, this meta-analysis suggests that MTR A2756G polymorphism may influence the development risk of pediatric ALL in Caucasians. Future large scale and well-designed studies are required to validate our findings.

A single-nucleotide polymorphism (rs1805087) in the methionine synthase (METH) gene increases the risk of prostate cancer

Methionine synthase (METH, i.e., MTR) is a key enzyme in the folate pathway, which plays a critical role in the synthesis, repair, and methylation of DNA. The association between METH gene polymorphisms and prostate cancer susceptibility remains ambiguous. Thus, we performed an updated meta-analysis of METH single-nucleotide polymorphism rs1805087 involving 12 independent case-control studies comprising 9986 prostate cancer patients and 40134 controls. The odds ratio and 95% confidence intervals were applied to evaluate the relation of this single-nucleotide polymorphism with prostate cancer. Statistical analysis was performed in STATA 11.0. A significant association was found between rs1805087 and increased prostate cancer risk, overall and with Hardy-Weinberg equilibrium. In subgroup analyses (based on ethnicity, source of control, genotyping methods, or publication status), similar associations were observed (e.g., genotype GA vs. AA: odds ratio 1.19, 95% confidence interval 1.01-1.40 among whites; G allele vs. A allele: odds ratio 1.14, 95% confidence interval 1.02-1.28 among hospital-based controls). Thus, the common polymorphism (rs1805087) of METH may be associated with increased prostate cancer risk. Further studies with a larger sample size and detailed gene-environment interactions should be conducted to identify the role of METH polymorphisms in prostate cancer susceptibility.

TSER polymorphism is not associated with risk of pediatric acute lymphoblastic leukemia: A meta-analysis

BACKGROUND

Accumulating studies have explored the effect of thymidylate synthase enhancer region (TSER) variation on risk of pediatric acute lymphoblastic leukemia (ALL) with controversial results. Therefore, this quantitative meta-analysis was performed to assess synthetically the association of TSER variation with susceptibility to develop pediatric ALL.

METHODS

The PubMed, ScienceDirect, Google Scholar, Wanfang Database, and China National Knowledge Infrastructure were systematically retrieved to obtain the published case-control studies about the relationship between TSER variation and pediatric ALL risk. The quality assessment of the included studies was preformed and relevant information was collected. Odds ratios (ORs) and 95% confidence intervals (CIs) were applied to evaluate the strength of association.

RESULTS

This meta-analysis finally included 2681 children with ALL and 3854 matched controls from 11 investigations. The quantitative synthesis results found no significant association between TSER variation and susceptibility to pediatric ALL in overall comparisons under 5 genetic models (2R/3R vs 3R/3R: OR = 0.95, 95% CI = 0.84-1.07, P = 0.41; 2R/2R vs 3R/3R: OR = 0.99, 95% CI = 0.84-1.16, P = 0.90; 2R2R vs 3R/3R+2R/3R: OR = 1.05, 95% CI = 0.92-1.21, P = 0.45; 2R/3R+2R/2R vs 3R/3R: OR = 0.97, 95% CI = 0.87-1.09, P = 0.63; 2R vs 3R: OR = 1.03, 95% CI = 0.92-1.15, P = 0.61). Similarly, there was no significant association existed in the stratification analyses according to ethnicity, control source, and quality score.

CONCLUSION

This meta-analysis shows that TSER variation is not related to the development risk of pediatric ALL.

Association of MTRR A66G polymorphism with cancer susceptibility: Evidence from 85 studies

Methionine synthase reductase (MTRR) is a key regulatory enzyme involved in the folate metabolic pathway. Previous studies investigating the association of MTRR A66G polymorphism with cancer susceptibility reported inconclusive results. We performed the current meta-analysis to obtain a more precise estimation of the possible association. Published literatures were identified from PubMed, Embase and CBM databases up to October 2016. The strength of the association between the MTRR A66G polymorphism and cancer susceptibility was assessed using odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Eighty five published studies with 32,272 cases and 37,427 controls were included in this meta-analysis. Pooled results indicated that the MTRR A66G polymorphism was associated with an increased overall cancer risk (homozygous model: OR = 1.08, 95% CI = 1.02-1.15, P = 0.009; recessive model: OR = 1.06, 95% CI = 1.00-1.12, P < 0.001 and allele comparison: OR = 1.03, 95% CI = 1.00-1.06, P < 0.001). Stratification analysis further indicated significant associations in head and neck cancer, Caucasians, Africans, and high quality studies. However, to avoid the "false-positive report", the significant findings were assessed by the false-positive report probability (FPRP) test. Interestingly, the results of FPRP test revealed that the increased risk for MTRR A66G polymorphism among Africans need further validation due to the high probabilities of false-positive results. This meta-analysis suggests that the MTRR A66G polymorphism is associated with significantly increased cancer risk, a finding that needs to be confirmed in single large studies.