MOLECULAR-BIOLOGY OF COLORECTAL ONCOGENESIS

Over the last 5 years there has been a rapid expansion of knowledge an d understanding regarding the molecular basis for colorectal cancer. I nitial observations suggested that at least four molecular events were important: ras mutations and loss of heterozygosity at the APC, p53 a nd DCC gene loci, respectively. Subsequently many other oncogenes and tumour suppressor genes have been identified which may play roles in t he genesis of colorectal cancer. In addition to identifying these gene s, research has started to focus on the biologic effects of such genet ic abnormalities. Our improved understanding of colorectal cancer biol ogy has clear clinical ramifications including: new screening strategi es, improved prognostication, treatment individualisation and in the l ong term, the possibility of 'gene therapies'.