Abstract |
The 5q- syndrome is a unique subtype of myelodysplastic syndromes typified by a relatively indolent course and responsiveness to lenalidomide. Here, we review the salient biologic features of this disease. Hemizygous deletion of a segment of chromosome 5q is believed to be the disease-initiating event. Recent molecular techniques have isolated the common deleted region and characterized key candidate genes contributing to the disease phenotype. Gene-specific RNA interference strategies revealed that haplo-insufficiency for the RPS14 gene, which encodes a ribosomal protein, is a critical effector of the p53-dependent erythroid hypoplasia and apoptotic loss of erythroid precursors. Disease-specific sensitivity to lenalidomide results from the drug's inhibitory effect on two haplodeficient phosphatases, PP2AcĪ± and CDC25c, which are coregulators of the G(2)/M checkpoint. Hyperphosphorylation of MDM2, as a result of inhibition of PP2A phosphatase activity, stabilizes MDM2, permitting p53 degradation and transition to G(2) arrest and clonal suppression. With the emerging data elucidating the pathogenesis of the 5q- syndrome and the success of clinical trials, a cohesive story connecting the biology and pharmacology associated with this subtype of myelodysplastic syndromes has emerged.
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Authors | Eric Padron, Rami Komrokji, Alan F List |
Journal | Expert review of hematology
(Expert Rev Hematol)
Vol. 4
Issue 1
Pg. 61-9
(Feb 2011)
ISSN: 1747-4094 [Electronic] England |
PMID | 21322779
(Publication Type: Journal Article, Review)
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Chemical References |
- Antineoplastic Agents
- Thalidomide
- Lenalidomide
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Topics |
- Anemia, Macrocytic
(genetics, metabolism, therapy)
- Antineoplastic Agents
(therapeutic use)
- Chromosome Deletion
- Chromosomes, Human, Pair 5
(genetics, metabolism)
- Clinical Trials as Topic
- Gene Deletion
- Humans
- Lenalidomide
- Thalidomide
(analogs & derivatives, therapeutic use)
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