Dynamics of genome alterations in Crohn’s disease associated colorectal carcinogenesis

To determine the pattern of copy number alterations that characterizes Crohn’s disease associated colorectal carcinomas (CD-CRCs), we performed array-based comparative genomic hybridization (aCGH) of CD-CRCs. As control group, we used histomorphologically similar sporadic mucinous colorectal adenocarcinomas. To gain insight into the dynamics of copy number alterations in CD associated colorectal tumor development, we additionally analyzed non-dysplastic, i.e., normal or inflamed, mucosa samples and dysplastic lesions from CD-CRC patients by aCGH. This revealed the gain of chromosome arm 5p as a distinctive feature of CD related colorectal carcinogenesis, while the overall pattern of copy number changes in CD-CRC was similar to sporadic mucinous CRC, including gains of chromosomes and chromosome arms 7, 8, 13 and 20q, and losses of 5q, 8p, 17p and 18q. We analyzed 73 tissue samples by aCGH. These comprised CD-CRCs (n = 32), dysplastic lesions (n = 3), inflamed mucosa samples (n = 7), histologically normal mucosa samples (n = 4), lymph node metastases (n = 2) and a local recurrence (n = 1) along with sporadic mucinous CRCs (n = 24). Biological replicates: 73.