title: Role of apical caspases and glucocorticoid-regulated genes in glucocorticoid-induced apoptosis of pre-B leukemic cells.
abstract: Glucocorticoid (GC) sensitivity in hematopoietic cells requires the activation and nuclear translocation of the glucocorticoid receptor (GR) and the subsequent activation of caspases. To gain insight into the caspase cascade responsible for the execution phase of GC-induced apoptosis, 697 pre-B leukemic cells were stably transfected with dominant negative forms of caspase-8, caspase-9, or caspase-10 and the caspase-8 inhibitor CrmA. We observed that inhibition of caspase-9 or caspase-10 activity, but not caspase-8, caused partial resistance of 697 cells to GC-induced apoptosis. Inhibition of multiple caspases through the use of specific peptide inhibitors had an additive effect and caused complete resistance. To identify GR-regulated genes upstream of caspase activation in 697 cells, we performed DNA microarray analysis. 113 genes were identified, which were induced or repressed at least 3-fold by GC. Surprisingly, mitogen-activated protein kinase phosphatase-1 (MKP-1), a GR-induced gene in other cell types, was repressed 3-fold and correlated with an induction of JNK activity. These results suggest the involvement of mitogen activated protein kinases and apical caspase-9 and caspase-10 in the GC-induced apoptosis of pre-B lymphocytes.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
authors.forename: Sonia L
authors.initials: SL
authors.lastname: Planey
authors.forename: Marc T
authors.initials: MT
authors.lastname: Abrams
authors.forename: Noreen M
authors.initials: NM
authors.lastname: Robertson
authors.forename: Gerald
authors.initials: G
authors.lastname: Litwack
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism*; D002470:Cell Survival; D002999:Clone Cells; D017931:DNA Primers; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases; D007700:Kinetics; D015448:Leukemia, B-Cell / Q000235:genetics / Q000473:pathology*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011289:Preleukemia / Q000235:genetics / Q000473:pathology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D017931:DNA Primers; D005938:Glucocorticoids; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D020169:Caspases