title: ADAM23 methylation and expression analysis in brain tumors.
abstract: The ADAMs comprises a family of cell surface proteins with putative roles in cell-cell and/or cell-matrix interactions and in protease activities. In this work, we have examined the expression level and the methylation status of the 5' upstream region of the adhesion molecule ADAM23 in two brain tumor cell lines (A172 and T98G) as well as in three primary brain tumors (one grade II astrocytoma and two meningiomas) and 15 glioblastoma xenografts. Using bisulfite sequencing we verified that the percentage of methylated dinucleotides is higher in T98G when compared to A172 and that methylation significantly correlates with ADAM23 mRNA and protein expression. However, we were unable to detect methylation and down-regulation of the ADAM23 gene in brain tumors. Together, these results indicate that ADAM23 down-regulation by methylation in brain tumors is a rare event and it may help explain why brain tumor metastases are rarely found elsewhere in the body.
authors.affiliation: Laboratory of Molecular Biology and Genomics, Ludwig Institute for Cancer Research, SP, Brazil.
authors.forename: Fabrício F
authors.initials: FF
authors.lastname: Costa
authors.forename: Christian
authors.initials: C
authors.lastname: Colin
authors.forename: Sueli M O
authors.initials: SM
authors.lastname: Shinjo
authors.forename: Silvio M
authors.initials: SM
authors.lastname: Zanata
authors.forename: Suely K N
authors.initials: SK
authors.lastname: Marie
authors.forename: Mari C
authors.initials: MC
authors.lastname: Sogayar
authors.forename: Anamaria A
authors.initials: AA
authors.lastname: Camargo
mesh_terms: D051722:ADAM Proteins; D000818:Animals; D001254:Astrocytoma / Q000235:genetics* / Q000378:metabolism; D001932:Brain Neoplasms / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D019175:DNA Methylation; D015536:Down-Regulation / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D005909:Glioblastoma / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D008579:Meningioma / Q000235:genetics* / Q000378:metabolism; D008666:Metalloendopeptidases / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009711:Nucleotides / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D008562:Membrane Glycoproteins; D009711:Nucleotides; D012333:RNA, Messenger; D051722:ADAM Proteins; C114633:ADAM23 protein, human; D008666:Metalloendopeptidases