Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myelodysplastic syndromes (MDS) represent a group of clonal hematopoietic disorders characterized by dyshemopoiesis and frequent evolution to acute leukemia. Tumor suppressor gene inactivation may be involved in MDS pathogenesis. The two families of cyclin-dependent kinase inhibitors (CDKIs) (INK4 family of p15, p16, p18 and p19 and CIP/KIP family of p21, p27 and p57) that negatively regulate cell cycle progression are known tumor suppressor genes. To determine whether genetic alterations of p16 and p27 genes play an important role in MDS pathogenesis, we examined DNA from 51 patients classified as 17 refractory anemias (RA), four refractory anemias with ringed sideroblasts (RARS), 19 refractory anemias with an excess of blasts (RAEB), 5 refractory anemias with excess of blasts in transformation (RAEB-t) and 6 chronic myelomonocytic leukemias (CMML). Southern blot analysis detected no homozygous deletions of p16 and p27. Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and sequencing did not reveal point mutations for both genes with the exception of two allelic polymorphisms, namely a C --> G transition at 447 bp of p16exon3 and a T --> A transition at 791 bp of p27exon1 genes. Our results suggest that mutations of p16 and p27 genes resulting in abnormal p16 and p27 proteins do not represent a mechanism of gene inactivation involved in the pathogenesis of MDS.
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PMID:Absence of p16 and p27 gene rearrangements and mutations in de novo myelodysplastic syndromes. 1610 74

Transcriptional silencing of tumor suppressor genes, associated with DNA methylation, is a common epigenetic event in hematologic malignancies. Although DNA hypermethylation of CpG islands is well described in acute leukemias and myelodysplastic syndromes, much less is known of the specific methylation changes that commonly occur in follicular B cell lymphomas. Earlier methylation studies of follicular lymphoma involved only cell lines; however there is a growing literature of methylation changes in primary human FL samples. Published studies of primary follicular lymphoma specimens have demonstrated that: androgen receptor, SHP1, and death-associated protein kinase genes are commonly methylated. By contrast, the cyclin dependent kinase inhibitors p15, p16, and p57 are uncommon epigenetic events in follicular lymphoma. Methylation of cyclin dependent kinase inhibitors is more common in high grade lymphomas, and may be an important step in the progression and transformation of follicular lymphoma. Further methylation studies in follicular lymphoma should investigate the prognostic and therapeutic significance of these epigenetic changes and investigate methylation of other genes. Finally, reactivation of methylated tumor suppressor genes through the use of hypomethylating agents is a promising and novel approach to the treatment of indolent and transformed follicular lymphomas.
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PMID:Tumor suppressor gene methylation in follicular lymphoma: a comprehensive review. 1702 65

This study was purposed to explore the expression of p57kip2 in the bone marrow of patients with de novo myelodysplastic syndrome (MDS) and its role in MDS pathogenesis, as well as the relationship between the expression of p57kip2 and SDF-1/CXCR4 signal. The expression of p57kip2 and CXCR4 in 67 de novo MDS patients was measured by real-time quantitative PCR. The percentage of CD34(+) cells in the bone marrow from MDS patients was measured by flow cytometry. 18 healthy volunteers were recruited for control. The effect of SDF-1 on p57kip2 expression in bone marrow mononuclear cell (BMMNC) from MDS or normal controls was investigated in vitro, and difference between them was compared. The results showed that low-risk MDS and high-risk MDS displayed a significant reduction of p57kip2 mRNA expression in BMMNC compared with that in control group (P < 0.001) and there was a negative correlation between p57kip2 expression and percentage of CD34(+) (r = -0.458, P < 0.001); the patients with abnormal karyotype showed lower expression of p57kip2 gene, compared to patients with normal karyotype (P = 0.045). Although the expression of CXCR4 had no difference between MDS patients and normal controls, a positive correlation between p57kip2 and CXCR4 in MDS patients was still found (r = 0.609, P < 0.001). Moreover, SDF-1 increased p57kip2 expression in normal BMMNC in dose-dependent manner, but BMMNC from MDS patients showed no response to SDF-1. SDF-1-induced p57 expression was blocked by AMD3100. It is concluded that the low expression of p57 gene in MDS may play a role in the pathogenesis of MDS. Furthermore, SDF-1-induced p57kip2 expression in BMMNC, and the decreasing response of BMMNC to SDF-1 may contribute to the low expression of p57kip2 in MDS patients.
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PMID:[Expression of p57kip2 in patients with de novo myelodysplastic syndrome and its relationship with SDF-1/CXCR4 axis]. 2254 Oct 97