Figure 1. Presence of autoantibodies in mice with colitis-associated cancer.

(a) Schematic overview of the AOM/DSS colorectal cancer model. Each rectangle represents one week. After an initial AOM injection (10 mg/kg), DSS was given in drinking water for a 2.5% final concentration (gray areas) followed by regular water. Histological staining for distal colon morphology and blood collection was performed at indicated days (black arrows). (b) Sera collected after the third DSS cycle (day 63) from 16 AOM/DSS-treated mice developing colorectal adenocarcinoma showed specific reactivity against p53, HCK, GTF2B, EDIL3, MST1/STK4, SRC and MAPKAPK3 with Annexin IV and GST as negative controls. Sera were tested by indirect ELISA using purified human recombinant proteins. NY-ESO-1 showed a weak response. Results are representative of two independent assays. C, vehicle-treated control mice. AD, AOM/DSS-treated mice. (c) Western blot analysis showed alterations in expression of p53, MAPKAPK3, MST1/STK4, EDIL3, GTF2B and SRC in distal colon from 5 AOM/DSS-treated and 5 control mice. Tubulin was used as loading control in the same gels. (d) Semi-quantitative PCR analysis showing mRNA expression in the distal colon tissue of AOM/DSS- and control mice. β-actin was used as a control. (c, d) WB and semi-quantitative PCR analyses were quantified by densitometry and normalized according to the expression of tubulin and β-actin, respectively. For the cropped images, samples from treated and control animals were run in the same gels under same experimental conditions and processed in parallel. Experiments were run in duplicate.