Identification of genes with a pathogenic role in colorectal tumour progression and metastasis

The metastasis of colorectal cancer (CRC) cells from the initial tumour to distant organs is a major problem in CRC patient survival, and a major organ of CRC metastasis is the liver.  Previous studies in this laboratory, and by others, showed that major genomic changes occur in colorectal cancer, and that the resulting metastases also exhibited these genomic changes. Furthermore, preliminary gene expression analysis of CRC tumours and their metastases  resulted in the identification of genes, as well as molecular pathways, which might play a role in CRC proliferation, invasion and metastasis, and a subset of these genes were found in the respective regions of genomic change (Stange et al. Gut 59, 1236-1244, 2010). 

The most significant candidate genes/gene products found during this initial CRC tumour genome/ expression screening are currently being analysed, in vitro, by transient/ stable over expression or shRNA induced inhibition of the respective candidate genes in established CRC cell lines. Proliferation, adhesion and migration assays are used to identify phenotypes, in vitro, and microarray analysis is being performed in order to find further interaction partners. Several further analyses such as chromosomal immunoprecipitation (ChIP), protein-protein binding studies and global DNA methylation are also being initiated for specific candidates.. Furthermore, the modified cell lines developed in this study will be used in a mouse metastasis model as a tool to analyse changes in the metastatic potential of these cells.

In a separate study, genes involved in CRC tumor formation and metastasis are being introduced into primary mouse intestine/ adenoma cells cultivated in a 3D in vitro organotypic culture system. Molecular biological analysis of these cells should allow further insights into the mechanisms responsible for CRC tumor formation and metastasis.