Possible roles of insulin, IGF-1 and IGFBPs in initiation and progression of colorectal cancer

Table 2 Comparisons of pre-operation and post-operation serum levels of biomarkers between colorectal cancer patients and healthy controls (x bar ± s)

Biomarker	Healthy controls (n = 650)	Pre-operation (n = 284)	Post-operation (n = 331)
Insulin (μIU/mL)	6.24 ± 4.70	9.82 ± 4.671	9.971 ± 6.011
IGF-1 (ng/mL)	136.73 ± 63.17	200.16 ± 44.071	209.84 ± 47.821
IGFBP-1 (ng/mL)	10.97 ± 3.58	12.23 ± 4.03	12.34 ± 4.31
IGFBP-3 (μg/mL)	9.24 ± 3.912	6.47 ± 3.053	7.05 ± 2.31
IGF-1/IGFBP-3	29.01 ± 10.002	39.02 ± 16.353	31.98 ± 13.49
Leptin (ng/mL)	9.01 ± 4.97	13.49 ± 8.351	13.79 ± 8.351

¹Compared to healthy controls, P < 0.001 and P < 0.05;

²Healthy controls compared to pre- and post- operation groups, which showed significant differences, P = 0.015 and P = 0.001;

³Pre-operation group compared to post-operation group, P = 0.02. IGF-1: Insulin-like growth factor-1; IFGBP-1: Insulin-like growth factor binding protein-1.