Colorectal carcinogenesis is associated with stromal expression of COL11A1 and COL5A2.

Collagen is the major component of the interstitial extracellular matrix (ECM). ECM is known to play an active role in numerous biological processes such as cell shape, proliferation, migration, differentiation, apoptosis as well as carcinogenesis. We used mRNA differential display RT-PCR to study differentially expressed genes in tissue samples from 24 colorectal cancers and four normal colon epithelia. Twenty of the 24 tumours showed expression of a gene COL11A1, not expressed in the normal samples. This gene is not normally expressed in adult colon tissue, but was here found to be expressed in 27 out of a total of 34 (79%) colorectal carcinomas. An analysis of other collagens showed that COL5A2 was not expressed in normal colon but was co-expressed with COL11A1 in the tumours. Our results suggest that stromal expression of COL11A1 and COL5A2 is associated with malignancy in colorectal cancer.