Fig. 1

NETs formation is enhanced in CRC, especially in Fn^−high CRC. A Representative images of FISH detection for Fn and representative IHC staining for CD66b in tissue sections from HCs, Fn^−low and Fn^−high CRC patients and their matched adjacent normal tissues. B The mean of IOD for CD66b IHC staining was analyzed utilizing the Image Pro Plus software. Data were quantified by densitometry calculated from 3 random fields of each tissue section from randomly selected HCs (n = 5), Fn^−low (n = 5) CRC patients, Fn^−high (n = 5) CRC patients and their matched adjacent normal tissues and are shown as fold changes relative to the HCs. C Representative images of FISH detection for Fn and representative IF images for MPO (red) and CitH3 (green) in tissue sections from HCs, Fn^−low and Fn^−high CRC patients and their matched adjacent normal tissues. D Western blot analysis of CitH3 expression in tissue samples from Fn^−low (n = 3) and Fn^−high (n = 3) CRC patients and their matched adjacent normal tissues. CitH3 protein levels were quantified by using densitometry and normalized to β-actin and are shown as fold changes compared to the control (Right). E Representative IF images for CitH3 in freshly isolated neutrophils from HCs, Fn^−low and Fn^−high CRC patients. F Western blot analysis of CitH3 expression in freshly isolated neutrophils from HCs (n = 3), Fn^−low (n = 3) and Fn^−high (n = 3) CRC patients. CitH3 protein levels were quantified by using densitometry and normalized to β-actin and are shown as fold changes compared to the control (Right). G ELISA analysis for MPO-DNA in the serum from HCs (n = 56), Fn^−low (n = 48) and Fn^−high (n = 47) CRC patients. H Correlation between serum MPO-DNA levels and -ΔCt of Fn quantification in the clinical fecal samples from CRC patients. White arrow: Fn; red arrow: CD66b.⁺ neutrophil. White scale bars: 100 μm; Black scale bars: 50 μm. *p < 0.05, **p < 0.01, ***p < 0.001