Epigenetic inactivation of endothelin-2 and endothelin-3 in colon cancer. Academic Article uri icon


  • Endothelin-1 (ET-1) and its receptors are overexpressed in human cancers, but much less is known about the roles of ET-2 and ET-3 in cancer etiology. We sought to examine human and rat colon tumors for dysregulation of ET-2 and ET-3 expression and determine the underlying mechanisms. Human primary colon cancers and carcinogen-induced rat colon tumors were subjected to real-time RT-PCR, immunoblotting and immunohistochemistry; EDN2 and EDN3 genes were examined by methylation-specific PCR, bisulfite sequencing and pyrosequencing; and forced expression of ET-2 and ET-3 was conducted in human colon cancer cells followed by real-time cell migration and invasion assays. Rat and human colon tumors had markedly reduced expression of ET-2 and ET-3 mRNA and protein compared with matched controls. Mechanistic studies revealed hypermethylation of EDN2 and EDN3 genes in human primary colon cancers and in a panel of human colon cancer cell lines. Forced expression of ET-2 and ET-3 attenuated significantly the migration and invasion of human colon cancer cells. We conclude that epigenetic inactivation of ET-2 and ET-3 occurs frequently in both rat and human colon cancers. Current therapeutic strategies target overexpressed members of the ET axis via small molecule inhibitors and receptor antagonists, but this work supports a complementary approach based on the re-expression of ET-2 and ET-3 as natural antagonists of ET-1 in colon cancer.

published proceedings

  • Int J Cancer

altmetric score

  • 0.25

author list (cited authors)

  • Wang, R., Lhr, C. V., Fischer, K., Dashwood, W. M., Greenwood, J. A., Ho, E., ... Dashwood, R. H.

citation count

  • 36

complete list of authors

  • Wang, Rong||Löhr, Christiane V||Fischer, Kay||Dashwood, W Mohaiza||Greenwood, Jeffrey A||Ho, Emily||Williams, David E||Ashktorab, Hassan||Dashwood, Michael R||Dashwood, Roderick H

publication date

  • March 2013