title: Circumvention of glucocorticoid resistance in childhood leukemia.
abstract: In this study, we determined if in vitro resistance to prednisolone and dexamethasone could be circumvented by cortivazol or methylprednisolone, or reversed by meta-iodobenzylguanidine in pediatric lymphoblastic and myeloid leukemia. As there were strong correlations between the LC50 values (drug concentration inducing 50% leukemic cell kill, LCK) of the different glucocorticoids and median prednisolone/methylprednisolone, prednisolone/dexamethasone and prednisolone/cortivazol LC50 ratios did not differ between the leukemia subtypes, we conclude that none of the glucocorticoids had preferential anti-leukemic activity. Meta-iodobenzylguanidine however, partially reversed glucocorticoid resistance in 19% of the lymphoblastic leukemia samples.
authors.affiliation: Department of Pediatric Hematology/Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands. eg.haarman@vumc.nl
authors.forename: E G
authors.initials: EG
authors.lastname: Haarman
authors.forename: G J L
authors.initials: GJ
authors.lastname: Kaspers
authors.forename: R
authors.initials: R
authors.lastname: Pieters
authors.forename: M M A
authors.initials: MM
authors.lastname: Rottier
authors.forename: A J P
authors.initials: AJ
authors.lastname: Veerman
mesh_terms: D049109:Cell Proliferation; D002648:Child; D003907:Dexamethasone / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy* / Q000473:pathology; D008775:Methylprednisolone / Q000627:therapeutic use*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000473:pathology; D011239:Prednisolone / Q000627:therapeutic use; D011281:Pregnatrienes / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured
chemical_list: D005938:Glucocorticoids; D011281:Pregnatrienes; D003907:Dexamethasone; D011239:Prednisolone; D008775:Methylprednisolone; C005924:cortivazol