Mutational Pathways in Colorectal Carcinoma Cell Lines.

ABSTRACT

We studied the nature of mutational events in two highly malignant human colorectal carcinoma cell lines. In HCT116, the frequency of micro-satellite instability as detected by the electrophoretic shifts in the allele sizes of micro-satellite DNA sequence was 22% and 80% in two loci (D16S303 and D16S295) of dinucleotide repeats. In SW620, we failed to detect such mutation at any of the two micro satellite loci studied. However, there was a high frequency loss of heterozygosity in the micro satellite locus D16S303. Such high frequency loss of the D16S303 allele extended to other linked loci covering about 9 mega base pairs (Mbp). This set of data indicates that at least two pathway are involved in the development of colon tumour.