Header

UZH-Logo

Maintenance Infos

Epigenetic regulation of L1CAM in endometrial carcinoma: comparison to cancer-testis (CT-X) antigens


Schirmer, Uwe; Fiegl, Heidi; Pfeifer, Marco; Zeimet, Alain G; Müller-Holzner, Elisabeth; Bode, Peter K; Tischler, Verena; Altevogt, Peter (2013). Epigenetic regulation of L1CAM in endometrial carcinoma: comparison to cancer-testis (CT-X) antigens. BMC Cancer, 13:156.

Abstract

BACKGROUND: L1CAM was originally identified as an adhesion molecule involved in neural development. In many human carcinomas L1CAM is over-expressed and is associated with a bad prognosis. We previously reported that L1CAM was absent in the vast majority of endometrioid endometrial carcinomas (ECs) (type 1) but was strongly expressed in the more aggressive serous and clear-cell ECs (termed type 2). The differential regulation of L1CAM in ECs is not well understood. Recent evidence suggests that it can be regulated by epigenetic mechanisms. Here we investigated the role of DNA-methylation of the L1CAM promoter for expression. We also studied the relationship to cancer testis (CT-X) antigens that co-localize with L1CAM on chromosome Xq28, a region that is often activated in human tumors. METHODS: We used EC cell lines and primary tumor tissues for our analysis. For expression analysis we employed RT-PCR and Western blotting. DNA-Methylation of the L1CAM promoter was determined after bisulfite conversation and DNA sequencing. Tumor tissues were examined by immunohistochemical (IHC) staining. RESULTS: We demonstrate that the treatment of L1CAM low/negative expressing EC cell lines with 5'-Azacytidine (5-AzaC) or knock-down of DNMT1 (DNA methyltransferase 1) as well as the HDAC (histone deacetylase) inhibitor Trichostatin A (TSA) up-regulated L1CAM at the mRNA and protein level. The L1CAM gene has two promoter regions with two distinct CpG islands. We observed that the expression of L1CAM correlated with hypermethylation in promoter 1 and 5-AzaC treatment affected the DNA-methylation pattern in this region. The CT-X antigens NY-ESO-1, MAGE-A3 and MAGE-A4 were also strongly up-regulated by 5-AzaC or knock-down of DNMT1 but did not respond to treatment with TSA. Primary EC tumor tissues showed a variable methylation pattern of the L1CAM promoter. No striking differences in promoter methylation were observed between tumor areas with L1CAM expression and those without expression. CONCLUSIONS: L1CAM expression correlated with methylation of the L1CAM promoter in EC cell lines. In negative cell lines L1CAM expression is up-regulated by epigenetic mechanism. Although genes localized on Xq28 are often re-expressed by human tumors, L1CAM and CT-X antigens show distinct regulation in response to HADC inhibitors and 5-AzaC.

Abstract

BACKGROUND: L1CAM was originally identified as an adhesion molecule involved in neural development. In many human carcinomas L1CAM is over-expressed and is associated with a bad prognosis. We previously reported that L1CAM was absent in the vast majority of endometrioid endometrial carcinomas (ECs) (type 1) but was strongly expressed in the more aggressive serous and clear-cell ECs (termed type 2). The differential regulation of L1CAM in ECs is not well understood. Recent evidence suggests that it can be regulated by epigenetic mechanisms. Here we investigated the role of DNA-methylation of the L1CAM promoter for expression. We also studied the relationship to cancer testis (CT-X) antigens that co-localize with L1CAM on chromosome Xq28, a region that is often activated in human tumors. METHODS: We used EC cell lines and primary tumor tissues for our analysis. For expression analysis we employed RT-PCR and Western blotting. DNA-Methylation of the L1CAM promoter was determined after bisulfite conversation and DNA sequencing. Tumor tissues were examined by immunohistochemical (IHC) staining. RESULTS: We demonstrate that the treatment of L1CAM low/negative expressing EC cell lines with 5'-Azacytidine (5-AzaC) or knock-down of DNMT1 (DNA methyltransferase 1) as well as the HDAC (histone deacetylase) inhibitor Trichostatin A (TSA) up-regulated L1CAM at the mRNA and protein level. The L1CAM gene has two promoter regions with two distinct CpG islands. We observed that the expression of L1CAM correlated with hypermethylation in promoter 1 and 5-AzaC treatment affected the DNA-methylation pattern in this region. The CT-X antigens NY-ESO-1, MAGE-A3 and MAGE-A4 were also strongly up-regulated by 5-AzaC or knock-down of DNMT1 but did not respond to treatment with TSA. Primary EC tumor tissues showed a variable methylation pattern of the L1CAM promoter. No striking differences in promoter methylation were observed between tumor areas with L1CAM expression and those without expression. CONCLUSIONS: L1CAM expression correlated with methylation of the L1CAM promoter in EC cell lines. In negative cell lines L1CAM expression is up-regulated by epigenetic mechanism. Although genes localized on Xq28 are often re-expressed by human tumors, L1CAM and CT-X antigens show distinct regulation in response to HADC inhibitors and 5-AzaC.

Statistics

Citations

9 citations in Web of Science®
11 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

114 downloads since deposited on 20 Aug 2013
17 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > University Hospital Zurich > Institute of Pathology and Molecular Pathology
Dewey Decimal Classification:610 Medicine & health
Language:English
Date:2013
Deposited On:20 Aug 2013 05:44
Last Modified:07 Dec 2017 22:00
Publisher:BioMed Central
ISSN:1471-2407
Free access at:PubMed ID. An embargo period may apply.
Publisher DOI:https://doi.org/10.1186/1471-2407-13-156
PubMed ID:23530769

Download

Download PDF  'Epigenetic regulation of L1CAM in endometrial carcinoma: comparison to cancer-testis (CT-X) antigens'.
Preview
Content: Published Version
Filetype: PDF
Size: 1MB
View at publisher
Licence: Creative Commons: Attribution 2.0 Generic (CC BY 2.0)