Format

Send to

Choose Destination
Cancer Res. 2019 Dec 1;79(23):6024-6031. doi: 10.1158/0008-5472.CAN-19-1529. Epub 2019 Oct 22.

Cys34 Adductomics Links Colorectal Cancer with the Gut Microbiota and Redox Biology.

Author information

1
School of Public Health, University of California, Berkeley, California.
2
Section of Nutrition and Metabolism, International Agency for Research on Cancer, Lyon, France.
3
Italian Institute for Genomic Medicine (IIGM), Torino, Italy.
4
MRC-PHE Centre for Environment & Health, Imperial College, London, United Kingdom.
5
Department of Statistics, University of California, Berkeley, California.
6
School of Public Health, University of California, Berkeley, California. srappaport@berkeley.edu.

Abstract

Chronic inflammation is an established risk factor for colorectal cancer. To study reactive products of gut inflammation and redox signaling on colorectal cancer development, we used untargeted adductomics to detect adduct features in prediagnostic serum from the EPIC Italy cohort. We focused on modifications to Cys34 in human serum albumin, which is responsible for scavenging small reactive electrophiles that might initiate cancers. Employing a combination of statistical methods, we selected seven Cys34 adducts associated with colorectal cancer, as well as body mass index (BMI; a well-known risk factor). Five adducts were more abundant in colorectal cancer cases than controls and clustered with each other, suggesting a common pathway. Because two of these adducts were Cys34 modifications by methanethiol, a microbial-human cometabolite, and crotonaldehyde, a product of lipid peroxidation, these findings further implicate infiltration of gut microbes into the intestinal mucosa and the corresponding inflammatory response as causes of colorectal cancer. The other two associated adducts were Cys34 disulfides of homocysteine that were less abundant in colorectal cancer cases than controls and may implicate homocysteine metabolism as another causal pathway. The selected adducts and BMI ranked higher as potentially causal factors than variables previously associated with colorectal cancer (smoking, alcohol consumption, physical activity, and total meat consumption). Regressions of case-control differences in adduct levels on days to diagnosis showed no statistical evidence that disease progression, rather than causal factors at recruitment, contributed to the observed differences. These findings support the hypothesis that infiltration of gut microbes into the intestinal mucosa and the resulting inflammation are causal factors for colorectal cancer. SIGNIFICANCE: Infiltration of gut microbes into the intestinal mucosa and the resulting inflammation are causal factors for colorectal cancer.

PMID:
31641032
PMCID:
PMC6891211
[Available on 2020-06-01]
DOI:
10.1158/0008-5472.CAN-19-1529

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center