Promoter Methylation Pattern of Caspase-8, P16INK4A, MGMT, TIMP-3, and E-Cadherin in Medulloblastoma

Martin EBINGER1, Leonore SENF2, Olga WACHOWSKI3, Wolfram SCHEURLEN2

1Department of Molecular Pathology, Institute of Pathology, Tübingen, Germany
2Cnopf'sche Kinderklinik, Nürnberg, Germany
3Zentrum für Kinderheilkunde und Jugendmedizin, University Hospital Gießen, Gießen, Germany


Methylation of promoter regions of CpG-rich sites is an important mechanism for silencing of tumor suppressor genes (TSG). To evaluate the role of tumor suppressor genes caspase-8 (CASP8), TIMP-3, E-cadherin (CDH1), p16INK4A, and MGMT in medulloblastoma tumorigenesis, 51 medulloblastomas (46 primary tumor specimens, 5 cell lines) were screened for methylation of promoter linked CpG-islands. For CASP8, we examined the 5' UTR region that has been shown to be associated with expression of CASP8. As detected by methylation specific PCR, methylation rate was low for TIMP-3 (3% of tumor samples; 1/5 cell lines), for MGMT (0% of tumor samples; 1/5 cell lines), for p16INK4A (2% of tumor samples; 2/5 cell lines) and for CDH1 (8% of tumor samples; 1/4 cell lines). CASP8, however, was methylated in 90% of tumor samples and 4/5 cell lines examined. Screening other tumor entities for CASP8 methylation, we found a similarly high level in 6 neuroblastoma cell lines in contrast to 5 osteosarcoma-, 4 Ewing's sarcoma- and 6 non-embryonic tumor cell lines without any increased promoter methylation. From our results we conclude that methylation of the CASP8 5' UTR region may play a role in inactivation of CASP8 in neural crest tumors. Pathology & Oncology Research, Vol 10, Nr 1, 17-21, 2004

Key words: aberrant promoter methylation; medulloblastoma; caspase-8; p16INK4A; MGMT; TIMP-3; CDH1

Received: Feb 1, 2004; accepted: Mar 1, 2004
Correspondence: Wolfram SCHEURLEN, Cnopf'sche Kinderklinik, St. Johannis-Mühlgasse 19 Nürnberg 90419, Germany; Tel: +49-911-3340-308, Fax: +49-911-3340-519; E-mail:

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