c-peptide and Colonic-Polyps

Dysregulated insulin signaling is thought to contribute to cancer risk.. To determine if insulin-related serum factors are associated with colon polyps, 126 asymptomatic men (48-65 years) were recruited at colonoscopy. Blood was collected. Odds ratios were determined using polytomous logistic regression for polyp number and type.. Males with serum C-peptide concentration >3.3 ng/mL were 3.8 times more likely to have an adenoma relative to no polyp than those with C-peptide ≤1.8 ng/mL. As C-peptide tertile increased, an individual was 2 times more likely to have an adenoma (P = 0.01) than no polyp. There were no associations between insulin-like growth factor or its binding proteins with polyp number or type. Males with soluble receptor for advanced glycation end products (sRAGE) concentration >120.4 pg/mL were 0.25 times less likely to have ≥3 polyps relative to no polyps compared with males with sRAGE ≤94.5 pg/mL. For each increase in sRAGE tertile, a man was 0.5 times less likely to have ≥3 polyps than no polyps (P = 0.03). Compared with males with a serum vascular endothelial growth factor (VEGF) concentration ≤104.7 pg/mL, males with a serum VEGF concentration >184.2 pg/mL were 3.4 times more likely to have ≥3 polyps relative to no polyps. As the VEGF tertile increased, a man was 1.9 times more likely to have ≥3 polyps than no polyps (P = 0.049).. Serum concentrations of C-peptide, sRAGE, and VEGF may indicate which men could benefit most from colonoscopy.. Identification of biomarkers could reduce medical costs through the elimination of colonoscopies on low-risk individuals.

Topics: Adenoma; Aged; C-Peptide; Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Glycation End Products, Advanced; Humans; Insulin; Logistic Models; Male; Middle Aged; Somatomedins; Vascular Endothelial Growth Factor A

Colon carcinogenesis is a multi-steps process in which many growth factors are involved. In some studies the increased risk of colon cancer development was observed in patients with diabetes mellitus type 2 with accompanying hyperinsulinemia. It is also known that insulin-like growth factor I (IGF-I) plays an important role in proliferation, growth, differentiation and inhibiting apoptosis of both epithelial and carcinoma cells. The aim of the study was to evaluate the serum concentration of insulin, C-peptide and IGF-I in patients with colon adenomas and colorectal cancer.. In 17 patients with colon cancer, 32 patients with colon adenomas and in 12 healthy persons the serum concentration of insulin, C-peptide and IGF-I was determined using ELISA kits.. In patients with colon cancer significantly higher serum IGF-I concentration comparing to the control group was observed (85.66 ng/ml vs. 60.96 ng/ml; p < 0.05). Higher IGF-I concentration was also observed in patients with distal tumors comparing to the proximal localisation (95.40 ng/ml vs. 64,65 ng/ml, p < 0.05) and in more differentiated tumors (84.36 ng/ml vs. 75.24 ng/ml). Similarly, higher C-peptide concentrations were observed in distal tumors (635.64 pmol/ I vs. 578.69 pmol/l) and in well-differentiated carcinoma (671.32 pmol/ I vs. 575.66 pmol/l). In patients with colon adenomatous polyps we also observed higher serum IGF-I concentrations I comparing to the control group (82.1 ng/ml vs. 60.96 ng/ml), in high dysplasia adenomas (84.12 ng/ml vs. 79.67 ng/ml) and in smaller adenomas to 1 cm diameter (97.98 ng/ml vs. 73.28 ng/ml), but the differences were not significant. We also observed higher concentration of C-peptide in patients with low grade dysplasia adenomas (665.24 pmol/l vs. 498.13 pmol/l) and with small polyps (611.51 pmol/l vs. 514.89 pmol/l). There were no differences in serum concentration of IGF-I and C-peptide between patients with tubular and villous adenomas. There was no statistical difference observed in insulin serum concentration in all groups of patients.. IGF-I is probably involved particularly in the early stage of colon carcinogenesis.

Topics: Adenoma; Adenomatous Polyps; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; C-Peptide; Colonic Polyps; Colorectal Neoplasms; Diabetes Mellitus, Type 2; Female; Humans; Hyperinsulinism; Insulin; Insulin-Like Growth Factor I; Male; Middle Aged