ag-490 and Myelodysplastic-Syndromes

To investigate the effect of Yisui Jiedu Recipe (YSJDR), a compound traditional Chinese herbal medicine, on cytokines and their corresponding just another kinase 2-signal transducers and activators of transcription 5 (JAK2-STAT5) signal transduction pathway in bone marrow hematopoietic cells from patients with myelodysplastic syndrome-refractory anemia (MDS-RA).. Fluorogenic quantitative polymerase chain reaction (FQ-PCR) method was established to detect the levels of JAK2, STAT5 and Bcl-xL mRNA expressions, and JAK2-STAT5 signal transduction pathway was activated by granulocyte-macrophage-colony stimulating factor (GM-CSF) in cultured bone marrow hematopoietic cells from 10 patients with MDS-RA. The levels of interleukin-2 (IL-2), interleukin-3 (IL-3), gamma-interferon (gamma-INF) and tumor necrosis factor-alpha (TNF-alpha) in the cultural supernatant of untreated control, AG490-treated and YSJDF-treated cells were measured by enzyme-linked immunosorbent assay.. The levels of IL-2 and TNF-alpha in YSJDR-treated group were significantly lower than those in untreated control group and AG490-treated group (P<0.01, P<0.05), and IL-3 level in YSJDP-treated group was remarkably higher than that in the other two groups (P<0.01). There were no significant differences in the levels of IL-2 and IL-3 between AG490-treated group and untreated control group (P>0.05), while the TNF-alpha level in AG490-treated group was decreased obviously as compared with the untreated control group (P<0.01). There was no significant difference in gamma-INF level between YSJDR-treated group and AG490-treated group (P>0.05), while TNF-alpha level in the two groups were significantly lower than that in the untreated control group (P<0.01). The expressions of JAK2, STAT5 and Bcl-xL mRNAs were significantly down-regulated in the YSJDR-treated and the AG490-treated groups as compared with those in the untreated control group (P<0.05, P<0.01), while there were no differences in the expressions of JAK2, STAT5 and Bcl-xL mRNAs between YSJDR-treated group and AG490-treated group.. YSJDR can modulate cytokine level in bone marrow hematopoietic cells of MDS-RA, suppress JAK2-STAT5 signal transduction, and inhibit the Bcl-xL mRNA expression.

Topics: Adult; Aged; Anemia, Refractory; Bone Marrow Cells; Cells, Cultured; Drugs, Chinese Herbal; Female; Hematopoiesis; Humans; Janus Kinase 2; Male; Middle Aged; Myelodysplastic Syndromes; RNA, Messenger; Signal Transduction; STAT5 Transcription Factor; Tyrphostins

Cells from patients with MDS-derived AML display heterogeneous proliferative responses to transforming growth factor beta (TGF beta). We analyzed growth inhibition and SMAD2 phosphorylation by TGF beta in CD34+ cells from nine patients, as compared to normal controls. While TGF beta consistently inhibited thymidine incorporation of normal cells (41% of control, P < 0.05), cells from patients with AML were growth-inhibited in only four of seven cases (40%), whereas TGF beta stimulated thymidine incorporation in the three other samples (166%). Remarkably, TPO reverted the stimulatory effect of TGF beta to profound growth inhibition. Upon exposure to TGF beta, SMAD2 protein was phosphorylated in normal CD34+ cells (n = 3), CD34+ leukemic blasts from all examined patients with AML (n = 4), and in the myeloid leukemic cell lines M-07e and HEL. TGF beta inhibited TPO-mediated thymidine incorporation, cell proliferation and survival in all samples analyzed. In M-07e cells and CD34+ cells from healthy donors, this inhibition was enhanced by an antagonist of JAK2 (AG490), but not a MEK-1 antagonist (PD098059). Conversely, in CD34+ cells from a patient with AML, both AG490 and PD098059 significantly enhanced TGF beta-mediated suppression of TPO-induced thymidine incorporation. Thus, in MDS-derived AML, altered responses to TGF beta may be due to defects downstream of SMAD2 and may involve MAPK activation.

Topics: Acute Disease; Adult; Antigens, CD34; Cell Division; Disease Progression; DNA Replication; DNA-Binding Proteins; DNA, Neoplasm; Enzyme Inhibitors; Flavonoids; Hematopoietic Stem Cells; Humans; Interleukin-3; Janus Kinase 2; Leukemia, Myeloid; MAP Kinase Kinase 1; MAP Kinase Signaling System; Mitogen-Activated Protein Kinase Kinases; Myelodysplastic Syndromes; Neoplasm Proteins; Neoplastic Stem Cells; Phosphorylation; Protein Processing, Post-Translational; Protein Serine-Threonine Kinases; Protein-Tyrosine Kinases; Proto-Oncogene Proteins; Reverse Transcriptase Polymerase Chain Reaction; Smad2 Protein; Thrombopoietin; Thymidine; Trans-Activators; Transforming Growth Factor beta; Tyrphostins