Metabolic biomarkers and the risk of molecular subtypes of colorectal cancer

• Background: Body fatness measured as high body mass index (BMI) increase the risk for colorectal cancer (CRC). The mechanisms behind the relationship are not fully understood, but might include insulin resistance and changes in adipokine concentrations produced by adipose tissue. Yet, associations between circulating biomarkers related to these mechanisms and CRC risk have been somewhat inconsistent, possibly due to CRC heterogeneity. To better understand the role of insulin resistance and adipokines in CRC development, we therefore investigated circulating biomarkers related to these mechanisms in relation to molecular subtypes of CRC.Methods: This was a prospective case-control study of 1010 cases and 1:1 matched controls nested within the population-based Northern Sweden Health and Disease Study (NSHDS). Concentrations of insulin, C-peptide, adiponectin, and leptin were quantified in prediagnostic plasma using immunoassays and related to CRC and CRC subtypes defined by mutations in BRAF and KRAS, and microsatellite instability (MSI) status analyzed in tumor tissue. Odds ratios (ORs) and 95% confidence intervals (CIs) for CRC by metabolic biomarker levels were calculated with conditional logistic regression.Results: Higher C-peptide and lower adiponectin were associated with an increased CRC risk (ORs per 1 standard deviation increase (95% CI): 1.11 (1.01, 1.23) and 0.91 (0.83, 1.00), respectively). The associations were attenuated when adjusting for BMI (ORs (95% CI): 1.07 (0.96, 1.19) and 0.93 (0.84, 1.03), respectively), with the potential exception of the association of C-peptide in women. Circulating insulin and leptin were not associated with CRC risk. We found no clear differences in the association between any biomarkers and CRC risk by molecular subtypes defined by KRAS and BRAF mutation status (Pheterogeneity>0.6), or MSI status (Pheterogeneity>0.3).Conclusion: Circulating biomarkers of insulin resistance and adipokines were not associated with CRC or specific molecular subtypes of CRC defined by KRAS and BRAF mutation or MSI status.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Cancer och onkologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cancer and Oncology (hsv//eng)

Keyword

Cancer Epidemiology

cancerepidemiologi

Publication and Content Type

vet (subject category)

ovr (subject category)