Figure 1. Key genes for stem/progenitor cell control which are frequently, and often concordantly, aberrantly silenced, in association with promoter CpG island DNA hypermethylation in pre-invasive colon lesions.

Figure 1Key genes for stem/progenitor cell control which are frequently, and often concordantly, aberrantly silenced, in association with promoter CpG island DNA hypermethylation in pre-invasive colon lesions.

The top panel shows that normal stem cells in adult intestinal cell epithelial renewal utilize the genes listed as epigenetic gatekeepers to control stem/progenitor cell proliferation and generate precursor cells which mature normally. When these genes are abnormally silenced, especially in groups, as shown in the colon polyps in the middle panel, this helps foster, abnormal, pre-invasive stem/progenitor cell expansion (red box showing neoplastic self-renewing cells), creating polyps and a cancer risk state. The risk state, as per the text, can foster oncogenic responses to key mutations which are labeled as the genetic gatekeepers. This combination of epigenetic and genetic abnormalities, and other recurring ones, can lead to invasive colon cancers built upon the self-renewing cells originally present and new ones created by the combination of molecular changes.

From: Stem cells, cancer, and epigenetics

Cover of StemBook
StemBook [Internet].
Cambridge (MA): Harvard Stem Cell Institute; 2008-.
Copyright: © 2009 Stephen B. Baylin.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.