title: Downregulation of ARFGEF1 and CAMK2B by promoter hypermethylation in breast cancer cells.
abstract: To identify novel genes that are regulated by promoter methylation, a combinational approach involving in silico mining followed by molecular assay was performed. From the expression microarray data registered in the European bioinformatics institute (EBI), genes showing downregulation in breast cancer cells were initially screened and then selected by e-Northern analysis using the Unigene database. A series of these in silico methods identified CAMK2B and ARFGEF1 as candidates, and the two genes were revealed to be hypermethylated in breast cancer cell lines and hypomethylated in normal breast cell lines. Additionally, cancer cell lines showed downregulated expression of these genes. Furthermore, treatment of the cancer cell lines with a demethylation agent, 5-Aza-2'-deoxycytidine, recovered expression of CAMK2B and ARFGEF1, implying that hypermethyaltion silenced gene activity in cancer cells. Taken together, promoter methylations of CAMK2B and ARFGEF1 are novel epigenetic markers identified in breast cancer cell lines and can be utilized for the application to clinical cancer tissues.
authors.affiliation: Department of Life Science, Dongguk University-Seoul, Korea.
authors.forename: Ju Hee
authors.initials: JH
authors.lastname: Kim
authors.forename: Tae Woo
authors.initials: TW
authors.lastname: Kim
authors.forename: Sun Jung
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D001374:Azacitidine / Q000494:pharmacology; D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics*; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D019295:Computational Biology; D019175:DNA Methylation / Q000187:drug effects / Q000235:genetics*; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics*; D044127:Epigenesis, Genetic / Q000187:drug effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic
chemical_list: C119087:ARFGEF1 protein, human; D020662:Guanine Nucleotide Exchange Factors; C517658:CAMK2B protein, human; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D001374:Azacitidine