High IGFBP-3 levels in marrow plasma in early-stage MDS: effects on apoptosis and hemopoiesis.
The pathophysiology of the myelodysplastic syndromes (MDS) is incompletely understood. Tumor necrosis factor (TNF)alpha levels are elevated, particularly in early-stage MDS, and apoptosis in marrow cells is upregulated. Observations in other models have shown a role for insulin-like growth factor binding protein 3 (IGFBP-3) in TNFalpha-mediated apoptosis. We observed increased levels of IGFBP-3 in the marrow plasma of patients with MDS (P = 0.005) and hypothesized that altered IGFBP-3 levels contribute to the dysregulation of hemopoiesis in MDS by affecting proliferation and apoptosis. Western analysis of marrow plasma from MDS patients revealed an increase in the ratio of intact vs fragmented IGFBP-3 in early-stage MDS (relative to controls) that decreased with MDS disease progression, suggesting increased proteolysis with more advanced disease. Thus, these results provide evidence for dysregulation of IGFBP-3 in patients with MDS. While the data are complex, they are consistent with a modulatory effect of IGFBP-3 on hemopoiesis in MDS. Conceivably, understanding these mechanisms may allow for the development of novel therapeutic strategies.
Wilson
H M P
HM
Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. hmwilson@u.washington.edu
Lesnikov
V
V
Plymate
S R
SR
Ward
J
J
Deeg
H J
HJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins; D001853:Bone Marrow / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000378:metabolism / Q000473:pathology; D006410:Hematopoiesis / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism* / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000378:metabolism; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; D018972:Insulin-Like Growth Factor Binding Protein 3; D008562:Membrane Glycoproteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha