title: Modulation of the c-myb, c-myc and p53 mRNA and protein levels during induced murine erythroleukemia cell differentiation.
abstract: The induction of murine erythroleukemia cells (MELC) to terminal differentiation by hexamethylene bisacetamide (HMBA) is accompanied by changes in the levels of c-myb and c-myc mRNA, and in p53 protein levels. We simultaneously examined the effects of HMBA on modulation of c-myb, c-myc and p53 mRNA and protein levels, and examined the relationship between these changes and commitment to terminal cell division. In MELC cultured with HMBA, c-myb protein levels paralleled c-myb mRNA levels except at 24h, when the protein level was equivalent to the level in control cultures, whereas the mRNA had decreased. The c-myc protein paralleled c-myc mRNA throughout induction. The p53 mRNA and protein behaved in a discordant fashion. The p53 protein decreased to very low levels between 4 and 8 h and remained low, while the mRNA, which initially decreased, reaccumulated by 24 and 48 h. Transfer of MELC after 12 to 48 h of culture with HMBA to medium without inducer resulted in rapid (less than 3 h) reaccumulation of the c-myb mRNA, c-myb protein, and p53 protein, and cessation of recruitment of cells to commitment. Cells already induced to commit to terminal differentiation continued to express the differentiated phenotype.
authors.affiliation: The DeWitt Wallace Research Laboratory, Memorial Sloan-Kettering Cancer Center, Cornell University, New York, NY 10021.
authors.forename: V M
authors.initials: VM
authors.lastname: Richon
authors.forename: R G
authors.initials: RG
authors.lastname: Ramsay
authors.forename: R A
authors.initials: RA
authors.lastname: Rifkind
authors.forename: P A
authors.initials: PA
authors.lastname: Marks
mesh_terms: D000081:Acetamides / Q000494:pharmacology; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D003907:Dexamethasone / Q000494:pharmacology; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D009363:Neoplasm Proteins / Q000032:analysis* / Q000235:genetics; D010750:Phosphoproteins / Q000032:analysis* / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000032:analysis* / Q000235:genetics; D020598:Proto-Oncogene Proteins c-myb; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger / Q000032:analysis*; D016159:Tumor Suppressor Protein p53
chemical_list: D000081:Acetamides; D009363:Neoplasm Proteins; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D020598:Proto-Oncogene Proteins c-myb; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; D003907:Dexamethasone; C014026:hexamethylene bisacetamide