Issn Print: 0147-5185
Publication Date: 2001/10/01
Colorectal Hyperplastic Polyps and the Risk of Cancer: More Information Needed
Jeremy Jass; Barbara Leggett
Excerpt
There must be a genetic basis to the alterations of migration, maturation, and exfoliation that characterize hyperplastic polyp epithelium. 1 We have described a novel gene that could be implicated. 3 Whereas the early genetic changes in adenomas contribute to the neoplastic genotype, the early changes in hyperplastic polyps may not. The hyperplastic polyp may serve as a privileged locale or sanctuary in which cells may accumulate genetic alterations that would normally lead to apoptosis. Demonstration of loss of expression of the DNA repair gene 0-6-methylguanine DNA methyltransferase 2 and the mismatch repair gene hMLH1 1 within subclones in hyperplastic polyps serves as evidence for this contention. Both alterations would be expected to result in multiple DNA alterations (methylguanine adducts and mismatches, respectively) leading in turn to an increased mutation rate. If hyperplastic cells are relatively resistant to apoptosis induced by DNA damage, they may accumulate genetic errors over a short time and this could be expressed as rapid malignant evolution. This would account for the observations described by Melato et al.
Facebook
Twitter
LinkedIn
Email
