TY - JOUR
T1 - Long range epigenetic silencing is a trans-species mechanism that results in cancer specific deregulation by overriding the chromatin domains of normal cells
AU - Forn, Marta
AU - Muñoz, Mar
AU - Tauriello, Daniele V.F.
AU - Merlos-Suárez, Anna
AU - Rodilla, Verónica
AU - Bigas, Anna
AU - Batlle, Eduard
AU - Jordà, Mireia
AU - Peinado, Miguel A.
PY - 2013/12
Y1 - 2013/12
N2 - DNA methylation and chromatin remodeling are frequently implicated in the silencing of genes involved in carcinogenesis. Long Range Epigenetic Silencing (LRES) is a mechanism of gene inactivation that affects multiple contiguous CpG islands and has been described in different human cancer types. However, it is unknown whether there is a coordinated regulation of the genes embedded in these regions in normal cells and in early stages of tumor progression. To better characterize the molecular events associated with the regulation and remodeling of these regions we analyzed two regions undergoing LRES in human colon cancer in the mouse model. We demonstrate that LRES also occurs in murine cancer invivo and mimics the molecular features of the human phenomenon, namely, downregulation of gene expression, acquisition of inactive histone marks, and DNA hypermethylation of specific CpG islands. The genes embedded in these regions showed a dynamic and autonomous regulation during mouse intestinal cell differentiation, indicating that, in the framework considered here, the coordinated regulation in LRES is restricted to cancer. Unexpectedly, benign adenomas in ApcMin/+ mice showed overexpression of most of the genes affected by LRES in cancer, which suggests that the repressive remodeling of the region is a late event. Chromatin immunoprecipitation analysis of the transcriptional insulator CTCF in mouse colon cancer cells revealed disrupted chromatin domain boundaries as compared with normal cells. Malignant regression of cancer cells by invitro differentiation resulted in partial reversion of LRES and gain of CTCF binding. We conclude that genes in LRES regions are plastically regulated in cell differentiation and hyperproliferation, but are constrained to a coordinated repression by abolishing boundaries and the autonomous regulation of chromatin domains in cancer cells.
AB - DNA methylation and chromatin remodeling are frequently implicated in the silencing of genes involved in carcinogenesis. Long Range Epigenetic Silencing (LRES) is a mechanism of gene inactivation that affects multiple contiguous CpG islands and has been described in different human cancer types. However, it is unknown whether there is a coordinated regulation of the genes embedded in these regions in normal cells and in early stages of tumor progression. To better characterize the molecular events associated with the regulation and remodeling of these regions we analyzed two regions undergoing LRES in human colon cancer in the mouse model. We demonstrate that LRES also occurs in murine cancer invivo and mimics the molecular features of the human phenomenon, namely, downregulation of gene expression, acquisition of inactive histone marks, and DNA hypermethylation of specific CpG islands. The genes embedded in these regions showed a dynamic and autonomous regulation during mouse intestinal cell differentiation, indicating that, in the framework considered here, the coordinated regulation in LRES is restricted to cancer. Unexpectedly, benign adenomas in ApcMin/+ mice showed overexpression of most of the genes affected by LRES in cancer, which suggests that the repressive remodeling of the region is a late event. Chromatin immunoprecipitation analysis of the transcriptional insulator CTCF in mouse colon cancer cells revealed disrupted chromatin domain boundaries as compared with normal cells. Malignant regression of cancer cells by invitro differentiation resulted in partial reversion of LRES and gain of CTCF binding. We conclude that genes in LRES regions are plastically regulated in cell differentiation and hyperproliferation, but are constrained to a coordinated repression by abolishing boundaries and the autonomous regulation of chromatin domains in cancer cells.
UR - http://www.scopus.com/inward/record.url?scp=84887990323&partnerID=8YFLogxK
U2 - 10.1016/j.molonc.2013.08.008
DO - 10.1016/j.molonc.2013.08.008
M3 - Article
C2 - 24035705
AN - SCOPUS:84887990323
SN - 1574-7891
VL - 7
SP - 1129
EP - 1141
JO - Molecular Oncology
JF - Molecular Oncology
IS - 6
ER -