HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 278, Issue 8, 6222-6228, February 21, 2003

This Article Full Text Full Text (PDF) All Versions of this Article: 278/8/6222    most recent M207627200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ishizaki, T. Articles by Ogawa, K. Search for Related Content PubMed PubMed Citation Articles by Ishizaki, T. Articles by Ogawa, K. Social Bookmarking                      What's this?

Loss of Igf2 Imprinting in Monoclonal Mouse Hepatic Tumor Cells Is Not Associated with Abnormal Methylation Patterns for the H19, Igf2, and Kvlqt1 Differentially Methylated Regions^*

Tomoaki Ishizaki, Masumi Yoshie, Yuji Yaginuma, Tatsuya Tanaka, and Katsuhiro Ogawa

From the Departments of Pathology and Neurosurgery, Asahikawa Medical College, 2-1-1-1 East, Midorigaoka, Asahikawa 078-8510, Japan

IGFII, the peptide encoded by the Igf2 gene, is a broad spectrum mitogen with important roles in prenatal growth as well as cancer progression. Igf2 is transcribed from the paternally inherited allele, whereas the linked H19 is transcribed from the maternal allele. Igf2 imprinting is thought to be maintained by differentially methylated regions (DMRs) located at multiple sites such as upstream of H19 and Igf2 and within Kvlqt1 loci. Biallelic expression (loss of imprinting (LOI)) of Igf2 is frequently observed in cancers, and a subset of Wilms' and intestinal tumors have been shown to exhibit abnormal methylation at H19DMR associated with loss of maternal H19 expression, but it is not known whether such changes are common in other neoplasms. Because cancers consist of diverse cell populations with and without Igf2 LOI, we established four independent monoclonal cell lines with Igf2 LOI from mouse hepatic tumors. We here demonstrate retention of normal differential methylation at H19, Igf2, or Kvlqt1 DMR by all of the cell lines. Furthermore, H19 was found to be expressed exclusively from the maternal allele, and levels of CTCF, a multifunctional nuclear factor that has an important role in the Igf2 imprinting, were comparable with those in normal hepatic tissues with no mutational changes detected. These data indicate that Igf2 LOI in tumor cells is not necessarily linked to abnormal methylation at H19, Igf2, or Kvlqt1 loci.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				H. Tanaka, M. Yamamoto, N. Hashimoto, M. Miyakoshi, S. Tamakawa, M. Yoshie, Y. Tokusashi, K. Yokoyama, Y. Yaginuma, and K. Ogawa Hypoxia-Independent Overexpression of Hypoxia-Inducible Factor 1{alpha} as an Early Change in Mouse Hepatocarcinogenesis Cancer Res., December 1, 2006; 66(23): 11263 - 11270. [Abstract] [Full Text] [PDF]