Evolving Thoughts

Evolution, culture, philosophy and chocolate! John Wilkins' continuing struggle to come to terms with impermanence... "Humanus sum, nihil humanum a me alienum puto" - Terence

Monday, March 27, 2006

Evolving cancers

Evolutionary Biology Research Techniques Predict Cancer

Here's an interesting study - precancerous tumours, those that are not yet proliferating but are mutant cell clusters, are more likely to become cancers if the genetic diversity in the cells is high. On reflection this is obvious - if becoming malignant depends on having a series of mutations that ends up with a cell line not apoptosing when crowded, then a variety of mutations that fail to stop growth will increase the chances that some further mutation will interfere with the apoptotic cascade[s]. But they did the hard empirical work and described 32,000 genotypes in precancerous lesions.

The logic of evolution (which in this case means both changes in allele frequency and also diversification, that is, a kind of cell phylogeny) is that the higher the viable variation, the more likely a viable further variant is. Since cell lineages are rather like asexual lineages of, say, bacteria, the same models ought to work.