Prolactin-induced expressionof cytokine-inducible SH2 signaling inhibitors in human hematopoietic progenitors
| Autor: | E.L Hooghe-Peters, Shlomit Cwikel, Shoshana Merchav, Luba Prolov, Ilana Silvian-Drachsler |
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| Přispěvatelé: | Pharmacology, Vrije Universiteit Brussel |
| Jazyk: | angličtina |
| Rok vydání: | 2001 |
| Předmět: |
Cancer Research
Transcription Genetic medicine.medical_treatment Antigens CD34 Suppressor of Cytokine Signaling Proteins chemistry.chemical_compound STAT5 Transcription Factor Receptor Cells Cultured medicine.diagnostic_test Reverse Transcriptase Polymerase Chain Reaction Intracellular Signaling Peptides and Proteins Hematology Protein-Tyrosine Kinases Fetal Blood Milk Proteins Recombinant Proteins DNA-Binding Proteins Haematopoiesis Cytokine Cord blood hormones hormone substitutes and hormone antagonists Signal Transduction Biology Immediate-Early Proteins src Homology Domains Suppressor of Cytokine Signaling 1 Protein Western blot Antigens CD Proto-Oncogene Proteins Genetics medicine Humans RNA Messenger Molecular Biology Infant Newborn Tyrosine phosphorylation Cell Biology Janus Kinase 2 Hematopoietic Stem Cells Molecular biology Reverse transcriptase In vitro Prolactin Repressor Proteins chemistry Gene Expression Regulation Trans-Activators Interleukin-3 Carrier Proteins |
| Popis: | The prolactin (PRL) receptor (PRLR) utilizes the JAK2/STAT-5 pathway and induces expression of cytokine-inducible SH2 (CIS)/JAK2 binding (JAB) signaling inhibitors. We and others recently showed that CIS-3 and JAB abolish PRLR-mediated JAK2 activation and STAT-5 activity, whereas CIS-1, CIS-2, and CIS-4 had a negligible effect. Human CD34(+) hematopoietic progenitors express PRLRs and respond to PRL in vitro by enhanced cytokine-induced colony formation. To assess the signaling mechanism(s) involved in PRL-mediated enhancement of hematopoiesis and to identify further the CIS/JAB targets for PRL-mediated cellular responses, we assayed the effect of PRL, alone or in the presence of interleukin-3 (IL-3), on activation of STAT-5 and expression of CIS/JAB RNA in human cord blood (CB) CD34(+) cells.Isolated CB CD34(+) cells were incubated in serum-free cultures in the absence or presence of recombinant human (rh)PRL, rhIL-3, or both. Cell lysates were subjected to Western blot analysis with anti-STAT-5 and anti-phospho-STAT-5 antibodies. Isolated RNA was subjected to semiquantitative reverse transcriptase polymerase chain reaction analysis of CIS/JAB expression.STAT-5 tyrosine phosphorylation was similarly induced by PRL and IL-3, with an additive effect detected in the presence of both stimuli. Both PRL and IL-3, alone or combined, failed to induce CIS-3 or JAB RNA expression in CD34(+) cells. Interferon-gamma had no effect on CIS-3/JAB induction in these cells. However, CIS-1 was induced by PRLIL-3PRL+IL-3, whereas CIS-2 expression was induced by PRL = IL-3PRL+IL-3.Our findings show that PRL induces activation of STAT-5 and expression of similar CIS/JAB family members as IL-3 does in human CB CD34(+) cells. Because CIS-1 abolishes STAT-5 activation via the IL-3 but not the PRL receptor, the hematopoietic growth-promoting effects of PRL may involve its capacity to provide sustained STAT-5-mediated stimulatory signals to the cells. |
| Databáze: | OpenAIRE |
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