Altered saturated and monounsaturated plasma phospholipid fatty acid profiles in adult males with colon adenomas

Abstract

Background: Altered lipid metabolism and plasma fatty acid (FA) levels are associated with colorectal cancer. Obesity and elevated waist circumference (WC) increase the likelihood of developing precancerous colon adenomas. Methods: Venous blood was collected from 126 males, ages 48 to 65 years, who received routine colonoscopies. Plasma phospholipid (PPL) FAs were isolated, derivatized, and then analyzed using gas chromatography. ORs and 95% confidence intervals were determined using polytomous logistic regression after adjusting for confounding factors [i.e., age, smoking, WC, and body mass index (BMI)]. Results: PPL palmitic acid (PA) was inversely correlated with the presence of colon adenomas (P=0.01). For each unit increase in palmitoleic acid (OR, 3.75; P=0.04) or elaidic acid (OR, 2.92; P=0.04), an individual was more likely to have adenomas relative to no colon polyps. Higher enzyme activity estimates (EAE) of stearoyl-CoA desaturase-1 (SCD-1; P=0.02) and elongation of very long chain fatty acids protein-6 (ELOVL-6; P=0.03) were associated with an individual being approximately 1.5 times more likely to have an adenoma compared with no polyps. Conclusions: PPL FAs and EAEs, which have previously been associated with colorectal cancer, are significantly different in those with adenomas when compared with those without polyps. PPL PA, elaidic acid, and SCD-1 and ELOVL-6 EAEs are associated with adenomas independent of BMI and WC. Impact: PPL PA, elaidic acid, and SCD-1 and ELOVL-6 EAEs are associated with adenomas even after adjusting for obesityrelated risk factors and may function as novel biomarkers of early colorectal cancer risk. Cancer Epidemiol Biomarkers Prev; 25(3); 498-506.