Plasma concentrations of advanced glycation end-products and colorectal cancer risk in the EPIC study.
Aglago EK., Schalkwijk CG., Freisling H., Fedirko V., Hughes DJ., Jiao L., Dahm CC., Olsen A., Tjønneland A., Katzke V., Johnson T., Schulze MB., Aleksandrova K., Masala G., Sieri S., Simeon V., Tumino R., Macciotta A., Bueno-de-Mesquita B., Skeie G., Gram IT., Sandanger T., Jakszyn P., Sánchez M-J., Amiano P., Colorado-Yohar SM., Gurrea AB., Perez-Cornago A., Mayén A-L., Weiderpass E., Gunter MJ., Heath AK., Jenab M.
Advanced glycation end-products (AGEs) are a heterogeneous group of compounds formed by the non-enzymatic reaction between amino-acids and reducing sugars, or dicarbonyls as intermediate compounds. Experimental studies suggest that AGEs may promote colorectal cancer, but prospective epidemiologic studies are inconclusive. We conducted a case-control study nested within a large European cohort. Plasma concentrations of three protein-bound AGEs: N ε-(carboxy-methyl)lysine (CML), N ε-(carboxy-ethyl)lysine (CEL) and N δ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) were measured by ultra-performance liquid chromatography tandem mass-spectrometry in baseline samples collected from 1,378 incident primary colorectal cancer cases and 1,378 matched controls. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were computed using conditional logistic regression for colorectal cancer risk associated with CML, CEL, MG-H1, total AGEs, and [CEL+MG-H1: CML] and [CEL:MG-H1] ratios. Inverse colorectal cancer risk associations were observed for CML (OR comparing highest to lowest quintile, ORQ5vs.Q1=0.40, 95%CI:0.27-0.59), MG-H1 (ORQ5vs.Q1=0.73, 95%CI:0.53 - 1.00) and total AGEs (OR Q5vs.Q1=0.52, 95%CI:0.37 - 0.73) whereas no association was observed for CEL. A higher [CEL+MG-H1: CML] ratio was associated with colorectal cancer risk (ORQ5vs.Q1=1.91, 95%CI:1.31-2.79). The associations observed did not differ by sex, or by tumour anatomical subsite. Although individual AGEs concentrations appear to be inversely associated with colorectal cancer risk, a higher ratio of methylglyoxal-derived AGEs versus those derived from glyoxal (calculated by [CEL+MG-H1: CML] ratio) showed a strong positive risk association. Further insight on the metabolism of AGEs and their dicarbonyls precursors, and their roles in colorectal cancer development is needed.