Genomic instability and chromosomal abnormalities of colorectal cancer

Dr Kanade Katsura (Visiting Researcher, Department of Pathology, Clare Hall)

Saturday, 28 October, 2000; 7:30-9:30pm

Erasmus Room, Queens' College

It has been considered that carcinogenesis is a multistep process of genetic abnormalities and that malfunction of a single gene could not suffice to create cancer. In colorectal tumours, it has been shown that sequential genetic changes occur during progression from adenoma to carcinoma. Then, what is the mechanism which causes multiple genetic abnormalities? Recently genomic instability has come to be regarded as the most important factor, and two distinct patterns of instability have been identified in colorectal tumour cells. One of these is the replication error phenotype characterised by instability of microsatellite sequence repeat length. The other is chromosomal instability, but the causes of this instability are not apparent.
I will discuss gemonic instability by showing data of chromosome analysis of colorectal cancer cell lines obtained by CGH (comparative genomic hybridisation) and SKY (spectrum karyotyping).