Physical activity and molecular subtypes of colorectal cancer: a pooled observational analysis and Mendelian randomisation study
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Background
Physical activity is associated with lower colorectal cancer (CRC) risk, but its association with molecular subtypes defined by genetic and epigenetic alterations of the disease is unclear. Such information may enhance the understanding of the mechanisms related to the benefits of physical activity.
Methods
Pooled observational (ncases=5,386, ncontrols=6,798; nstudies=5) and genome-wide association data (ncases=8,178, ncontrols=10,472; nstudies=5) were utilised. We used multivariable logistic regression models and Mendelian randomisation (MR) to assess the association between physical activity and the risk of CRC subtypes defined by individual tumour markers (and marker combinations), namely microsatellite instability (MSI) status, CpG island methylator phenotype (CIMP) status, BRAF and KRAS mutations. We used case-only analysis to test for differences between molecular subtypes. We applied Bonferroni correction to account for multiple tests.
Results
In the pooled observational analysis, higher levels of physical activity were associated with lower CRC risk (ORObs-per 1SD=0.94, 95%CI 0.90-0.97), with an association that was stronger in males (ORObs-per 1SD=0.91, 95%CI 0.87-0.96) than in females (ORObs-per 1SD=0.97, 95%CI 0.91-1.03) (Pinteraction=0.04). Higher physical activity was associated with a lower risk of CRC across all molecular subtypes, especially in males. There was no difference in the associations by subtypes by pooled observational or MR analyses. The findings did not differ by study design, anatomical site, and early or late age onset of CRC.
Conclusions
Our findings suggest that physical activity is not differentially associated with the four major molecular subtypes involved in colorectal carcinogenesis, indicating that its benefits extend broadly across colorectal cancer pathogenesis.
Physical activity is associated with lower colorectal cancer (CRC) risk, but its association with molecular subtypes defined by genetic and epigenetic alterations of the disease is unclear. Such information may enhance the understanding of the mechanisms related to the benefits of physical activity.
Methods
Pooled observational (ncases=5,386, ncontrols=6,798; nstudies=5) and genome-wide association data (ncases=8,178, ncontrols=10,472; nstudies=5) were utilised. We used multivariable logistic regression models and Mendelian randomisation (MR) to assess the association between physical activity and the risk of CRC subtypes defined by individual tumour markers (and marker combinations), namely microsatellite instability (MSI) status, CpG island methylator phenotype (CIMP) status, BRAF and KRAS mutations. We used case-only analysis to test for differences between molecular subtypes. We applied Bonferroni correction to account for multiple tests.
Results
In the pooled observational analysis, higher levels of physical activity were associated with lower CRC risk (ORObs-per 1SD=0.94, 95%CI 0.90-0.97), with an association that was stronger in males (ORObs-per 1SD=0.91, 95%CI 0.87-0.96) than in females (ORObs-per 1SD=0.97, 95%CI 0.91-1.03) (Pinteraction=0.04). Higher physical activity was associated with a lower risk of CRC across all molecular subtypes, especially in males. There was no difference in the associations by subtypes by pooled observational or MR analyses. The findings did not differ by study design, anatomical site, and early or late age onset of CRC.
Conclusions
Our findings suggest that physical activity is not differentially associated with the four major molecular subtypes involved in colorectal carcinogenesis, indicating that its benefits extend broadly across colorectal cancer pathogenesis.
Date Issued
2025-12-01
Date Acceptance
2025-09-18
Citation
JNCI Cancer Spectrum, 2025, 9 (6)
ISSN
2515-5091
Publisher
Oxford University Press
Journal / Book Title
JNCI Cancer Spectrum
Volume
9
Issue
6
Copyright Statement
© The Author(s) 2025. Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
10.1093/jncics/pkaf095/8269781
Publication Status
Published
Article Number
pkaf095
Date Publish Online
2025-10-01