Dataset Information

Mendelian randomization study of causal link from gut microbiota to colorectal cancer.

ABSTRACT: Recent studies have shown the relevance of gut microbiota in the occurrence and development of colorectal cancer (CRC), but the causal relationship remains unclear in the human population. The present study aims to assess the causal relationship from the gut microbiota to CRC and to identify specific causal microbe taxa via genome-wide association study (GWAS) summary statistics based two-sample Mendelian randomization (MR) analyses. Microbiome GWAS (MGWAS) in the TwinsUK 1,126 twin pairs was used as discovery exposure sample, and MGWAS in 1,812 northern German participants was used as replication exposure sample. GWAS of CRC in 387,156 participants from the UK Biobank (UKB) was used as the outcome sample. Bacteria were grouped into taxa features at both family and genus levels. In the discovery sample, a total of 30 bacteria features including 15 families and 15 genera were analyzed. Five features, including 2 families (Verrucomicrobiaceae and Enterobacteriaceae) and 3 genera (Akkermansia, Blautia, and Ruminococcus), were nominally significant. In the replication sample, the genus Blautia (discovery beta=-0.01, P = 0.04) was successfully replicated (replication beta=-0.18, P = 0.01) with consistent effect direction. Our findings identified genus Blautia that was causally associated with CRC, thus offering novel insights into the microbiota-mediated CRC development mechanism.

SUBMITTER: Ni JJ

PROVIDER: S-EPMC9804960 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mendelian randomization study of causal link from gut microbiota to colorectal cancer.

Ni Jing-Jing JJ Li Xiao-Song XS Zhang Hong H Xu Qian Q Wei Xin-Tong XT Feng Gui-Juan GJ Zhao Min M Zhang Zi-Jia ZJ Zhang Lei L Shen Gen-Hai GH Li Bin B

BMC cancer 20221230 1

Recent studies have shown the relevance of gut microbiota in the occurrence and development of colorectal cancer (CRC), but the causal relationship remains unclear in the human population. The present study aims to assess the causal relationship from the gut microbiota to CRC and to identify specific causal microbe taxa via genome-wide association study (GWAS) summary statistics based two-sample Mendelian randomization (MR) analyses. Microbiome GWAS (MGWAS) in the TwinsUK 1,126 twin pairs was us ...[more]

PMID: 36585646

Similar Datasets

Project description:BackgroundThere have been previously reported associations between the gut microbiota, immune cells, and colorectal cancer; however, the specific mechanisms underlying these relationships remain largely unexplored and require further research. Therefore, in this study, we aimed to unravel the interactions between the gut microbiota, immune cells, and colorectal cancer.MethodsThe analysis used genome-wide association study (GWAS) data encompassing 207 microbial taxa and 205 functional pathways and data on 731 immune cell phenotypes. Colorectal cancer data on 6 581 cases and 463 421 controls were sourced from the Integrative Epidemiology Unit Open GWAS Project. Univariate inverse-variance weighted Mendelian randomization analysis was used to identify gut microbial taxa associated with colorectal cancer. Mediation analysis was used to identify the mediating role of specific immune cells in the link between gut bacteria and colorectal cancer.ResultsUnivariate inverse-variance weighted Mendelian randomization analysis revealed that several microbial taxa from the Actinobacteria and Firmicutes phyla were significantly associated with colorectal cancer. Coriobacteriaceae (odds ratio [OR]: 0.84, 95% confidence interval [CI]: 0.72-0.97), Sutterellaceae (OR: 0.88, 95% CI: 0.78-0.99), Eggerthella (OR: 0.91, 95% CI: 0.84-0.99), Coriobacteriales (OR: 0.84, 95% CI: 0.72-0.97), Collinsella aerofaciens (OR: 0.85, 95% CI: 0.74-0.99), and Ruminococcus bromii (OR: 0.91, 95% CI: 0.83-0.99) were negatively associated with colorectal cancer, whereas Lactobacillales (OR: 1.11, 95% CI: 1.03-1.20), Veillonella (OR: 1.08, 95% CI: 1.01-1.15), and Bifidobacterium bifidum (OR: 1.05, 95% CI: 1.00-1.09) were positively associated with colorectal cancer. Mediation analysis revealed that in the causal pathway from Collinsella aerofaciens to colorectal cancer, CD127 on CD28+ CD45RA- CD8br and human leukocyte antigen (HLA) DR on CD33- HLA DR+, mediated 11.30% and - 6.52% of the effect, respectively, and that in the causal pathway from Ruminococcus bromii to colorectal cancer, IgD- CD38dim %lymphocyte mediated - 14.80% of the effect.ConclusionsThese results highlight the potential of gut microbiota and immune cell phenotypes as novel treatment strategies for colorectal cancer.

Project description:BackgroundA number of recent observational studies have indicated a correlation between the constitution of gut microbiota and the incidence of pancreatitis. Notwithstanding, observational studies are unreliable for inferring causality because of their susceptibility to confounding, bias, and reverse causality, the causal relationship between specific gut microbiota and pancreatitis is still unclear. Therefore, our study aimed to investigate the causal relationship between gut microbiota and four types of pancreatitis.MethodsAn investigative undertaking encompassing a genome-wide association study (GWAS) comprising 18,340 participants was undertaken with the aim of discerning genetic instrumental variables that exhibit associations with gut microbiota, The aggregated statistical data pertaining to acute pancreatitis (AP), alcohol-induced AP (AAP), chronic pancreatitis (CP), and alcohol-induced CP (ACP) were acquired from the FinnGen Consortium. The two-sample bidirectional Mendelian randomization (MR) approach was utilized. Utilizing the Inverse-Variance Weighted (IVW) technique as the cornerstone of our primary analysis. The Bonferroni analysis was used to correct for multiple testing, In addition, a number of sensitivity analysis methodologies, comprising the MR-Egger intercept test, the Cochran's Q test, MR polymorphism residual and outlier (MR-PRESSO) test, and the leave-one-out test, were performed to evaluate the robustness of our findings.ResultsA total of 28 intestinal microflora were ascertained to exhibit significant associations with diverse outcomes of pancreatitis. Among them, Class Melainabacteria (OR = 1.801, 95% CI: 1.288-2.519, p = 0.008) has a strong causality with ACP after the Bonferroni-corrected test, in order to assess potential reverse causation effects, we used four types of pancreatitis as the exposure variable and scrutinized its impact on gut microbiota as the outcome variable, this analysis revealed associations between pancreatitis and 30 distinct types of gut microflora. The implementation of Cochran's Q test revealed a lack of substantial heterogeneity among the various single nucleotide polymorphisms (SNP).ConclusionOur first systematic Mendelian randomization analysis provides evidence that multiple gut microbiota taxa may be causally associated with four types of pancreatitis disease. This discovery may contribute significant biomarkers conducive to the preliminary, non-invasive identification of Pancreatitis. Additionally, it could present viable targets for potential therapeutic interventions in the disease's treatment.

Project description:IntroductionPrevious studies have proposed a possible gut-skin axis, and linked gut microbiota to psoriasis risks. However, there is heterogeneity in existing evidence. Observational research is prone to bias, and it is hard to determine causality. Therefore, this study aims to evaluate possible causal associations between gut microbiota (GM) and psoriasis.MethodsWith published large-scale GWAS (genome-wide association study) summary datasets, two-sample Mendelian randomization (MR) was performed to sort out possible causal roles of GM in psoriasis and arthropathic psoriasis (PsA). The inverse variance weighted (IVW) method was taken as the primary evaluation of causal association. As complements to the IVW method, we also applied MR-Egger, weighted median. Sensitivity analyses were conducted using Cochrane's Q test, MR-Egger intercept test, MR-PRESSO (Mendelian Randomization Pleiotropy RESidual Sum and Outlier) global test, and leave-one-out analysis.ResultsBy primary IVW analysis, we identified nominal protective roles of Bacteroidetes (odds ratio, OR 0.81, P = 0.033) and Prevotella9 (OR 0.87, P = 0.045) in psoriasis risks. Bacteroidia (OR 0.65, P = 0.03), Bacteroidales (OR 0.65, P = 0.03), and Ruminococcaceae UCG002 (OR 0.81, P = 0.038) are nominally associated with lower risks for PsA. On the other hand, Pasteurellales (OR 1.22, P = 0.033), Pasteurellaceae (OR 1.22, P = 0.033), Blautia (OR 1.46, P = 0.014), Methanobrevibacter (OR 1.27, P = 0.026), and Eubacterium fissicatena group (OR 1.21, P = 0.028) are nominal risk factors for PsA. Additionally, E. fissicatena group is a possible risk factor for psoriasis (OR 1.22, P = 0.00018). After false discovery rate (FDR) correction, E. fissicatena group remains a risk factor for psoriasis (PFDR = 0.03798).ConclusionWe comprehensively evaluated possible causal associations of GM with psoriasis and arthropathic psoriasis, and identified several nominal associations. E. fissicatena group remains a risk factor for psoriasis after FDR correction. Our results offer promising therapeutic targets for psoriasis clinical management.

Project description:BackgroundThe gut microbiota has been found to be associated with the risk of lung cancer. However, its causal relationship with various types of lung cancer remains unclear.MethodsWe conducted a Mendelian randomization (MR) study using the largest genome-wide association analysis of gut microbiota data to date from the MiBioGen consortium, with pooled statistics for various types of lung cancer from the Transdisciplinary Research in Cancer of the Lung, the International Lung Cancer Consortium, and FinnGen Consortium R7 release data. Inverse variance weighted, weighted model, MR-Egger regression, and weighted median were adapted to assess the causal relationship between gut microbiota and various types of lung cancer. Sensitivity analysis was used to test for the presence of pleiotropy and heterogeneity in instrumental variables. A reverse MR analysis was performed on these bacteria to determine their potential role in causing lung cancer. A reverse MR analysis was performed on these bacteria to determine their potential role in causing lung cancer. Multivariable Mendelian randomization (MVMR) was conducted to assess the direct causal impact of gut microbiota on the risk of various types of lung cancer.ResultsUsing IVW as the primary analytical method, we identified a total of 40 groups of gut microbiota with potential causal associations with various subtypes of lung cancer, of which 10 were associated with lung cancer, 10 with lung adenocarcinoma, 9 with squamous cell lung cancer, and 11 groups of bacteria associated with small cell lung cancer. After performing FDR correction, we further found that there was still a significant causal relationship between Peptococcaceae and lung adenocarcinoma. Sensitivity analyses demonstrated the robustness of these results, with no heterogeneity or pleiotropy found.ConclusionsOur results confirm a causal relationship between specific gut microbiota and lung cancer, providing new insights into the role of gut microbiota in mediating the development of lung cancer.

Project description:BackgroundGut microbiota is associated with endometrial cancer (EC); however, the causal relationship remains unexplored. This study attempted to explore the relationship between gut microbiota and EC using Mendelian randomization (MR) methods.MethodsIn this two-sample MR analysis, we used MiBioGen's gut microbiota data as the exposure and three datasets from European populations with EC as the outcome. The EC datasets included general EC, endometrioid histology, and non-endometrioid histology. Single nucleotide polymorphism (SNP) was used as the instrumental variable. Inverse variance weighted (IVW), multiplicative random effects IVW (MRE-IVW), Maximum likelihood (ML), MR Egger, MR-PRESSO, and the weighted median were used to perform MR analysis. Sensitivity analysis was conducted to assess the reliability of the results.ResultsIn this MR analysis of three EC datasets, specific gut microbiota were identified as potentially associated with different pathological types of EC. For general EC (ID: ebi-a-GCST006464), Family.Acidaminococcaceae (OR = 1.23, 95%CI: 1.02-1.48) and genus.Butyrivibrio (OR = 1.08, 95%CI: 1.01-1.16) were identified as risk factors, while genus.Ruminococcaceae UCG014 (OR = 0.82, 95%CI: 0.69-0.98) and genus.Turicibacter (OR = 0.84, 95%CI: 0.73-0.97) appeared to have protective effects. For endometrioid histology EC (ID: ebi-a-GCST006465), Family.Acidaminococcaceae (OR = 1.27, 95%CI: 1.01-1.59) and genus.Butyrivibrio (OR = 1.10, 95%CI: 1.01-1.19) were identified as risk factors, while several microbiota, including Family.Lactobacillaceae, genus.Coprococcus3, genus.Dorea, genus.Flavonifractor, genus.Lactobacillus, genus.Paraprevotella, and genus.Turicibacter, were identified as protective factors. For non-endometrioid histology EC (ID: ebi-a-GCST006466), Family.Rhodospirillaceae (OR = 1.41, 95%CI: 1.01-1.96) and genus.Peptococcus (OR = 1.43, 95%CI: 1.07-1.91) were identified as risk factors, while no significant protective factors were identified.ConclusionsThis two-sample MR study has identified gut microbiota with potential causal relationships with EC, varying by pathological type. These findings provide new insights into the pathogenesis of EC and suggest directions for future research on diagnosis and treatment strategies.

Dataset Information

Mendelian randomization study of causal link from gut microbiota to colorectal cancer.

Publications

Mendelian randomization study of causal link from gut microbiota to colorectal cancer.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets