Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D03343 (MDS)
 2,225 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the potential role of defective DNA-mismatch repair (MMR) as a mediator of leukemogenic susceptibility in patients with therapy-related myelodysplasia (t-MDS) and leukemia (t-leuk). Thirty-seven individuals with t-MDS/t-leuk were analyzed for microsatellite instability (MSI), the hallmark of defective DNA-MMR. Using standardized international criteria, 5/37 (14%) patients displayed high MSI, whereas 3 other patients had low MSI (8%). To determine the stage at which MSI had developed, we analyzed the primary tumors of 12 patients. Three of 4 patients with high MSI t-MDS/t-leuk also had microsatellite unstable primary tumors. Conversely, MSI was not detected in any primary malignancy of patients with low MSI or microsatellite stable t-MDS/t-leuk (P = 0.0182). In the high MSI group, we further investigated genes targeted by defective DNA-MMR (BAX, TGFBRII, IGFIIR, Caspase-5, APC, PTEN, E2F4, MBD4, MSH6, and MSH3) in both primary tumor and t-MDS/t-leuk. However, no mutation was found in any gene. The significant association of MSI in t-MDS/t-leuk and corresponding primary tumors suggests that defective DNA-MMR confers leukemogenic susceptibility to this cohort of patients.
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PMID:Defective DNA-mismatch repair: a potential mediator of leukemogenic susceptibility in therapy-related myelodysplasia and leukemia. 1197 58

Therapy-related myelodysplastic syndrome and acute myeloid leukemia (t-MDS/t-AML) are late complications of cytotoxic therapy used in the treatment of malignant diseases. The most common subtype of t-AML ( approximately 75% of cases) develops after exposure to alkylating agents, and is characterized by loss or deletion of chromosome 5 and/or 7 [-5/del(5q), -7/del(7q)], and a poor outcome (median survival 8 months). In the University of Chicago's series of 386 patients with t-MDS/t-AML, 79 (20%) patients had abnormalities of chromosome 5, 95 (25%) patients had abnormalities of chromosome 7, and 85 (22%) patients had abnormalities of both chromosomes 5 and 7. t-MDS/t-AML with a -5/del(5q) is associated with a complex karyotype, characterized by trisomy 8, as well as loss of 12p, 13q, 16q22, 17p (TP53 locus), chromosome 18, and 20q. In addition, this subtype of t-AML is characterized by a unique expression profile (higher expression of genes) involved in cell cycle control (CCNA2, CCNE2, CDC2), checkpoints (BUB1), or growth (MYC), loss of expression of IRF8, and overexpression of FHL2. Haploinsufficiency of the RPS14, EGR1, APC, NPM1, and CTNNA1 genes on 5q has been implicated in the pathogenesis of MDS/AML. In previous studies, we determined that Egr1 acts by haploinsufficiency and cooperates with mutations induced by alkylating agents to induce myeloid leukemias in the mouse. To identify mutations that cooperate with Egr1 haploinsufficiency, we used retroviral insertional mutagenesis. To date, we have identified two common integration sites involving genes encoding transcription factors that play a critical role in hematopoiesis (Evi1 and Gfi1b loci). Of note is that the EVI1 transcription factor gene is deregulated in human AMLs, particularly those with -7, and abnormalities of 3q. Identifying the genetic pathways leading to t-AML will provide new insights into the underlying biology of this disease, and may facilitate the identification of new therapeutic targets.
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PMID:Cytogenetic and genetic pathways in therapy-related acute myeloid leukemia. 1995 52

This study was purposed to investigate the significance of genomic comprehensive analysis information in diagnosis, therapy and prognosis of MDS through comprehensive analysis of a patient with MDS. The bone marrow specimen from a patient with MDS was comprehensively analyzed by a combination of genomic approaches, including chromosomal karyotyping, fluorescence in situ hybridization (FISH), genome scanning using Affymetrix high density SNP microarray platform, and next-generation sequencing (NGS) analysis using IonTorrent Cancer Gene Panel. The results showed that an abnormal clone was identified by standard G-banding karyotyping and confirmed by FISH, which contains interstitial deletions on the long arms of chromosome 5 and 11 respectively. SNP-array analysis defined the two genomic deletions to be an 81 Mb interstitial deletion on the long are of chromosome 5 and a 24 Mb interstitial deletion on the long are of chromosome 11. Meanwhile, SNP-array detected two genomic regions with acquired loss of heterozygosity (LOH), a 58 Mb region on the short arm of chromosome 1 and a 39 Mb region on the distal end of the long arm of chromosome 14. In addition, SNP-array identified multiple genomic regions with long stretch of absence of heterozygosity, representing about 5.3% of autosomal genome, indication a certain level of consanguinity between the parents. No clinically significant gene mutation was identified using IonTorrent 50 Cancer Gene Panel while 6 polymorphisms within 6 genes were observed including APC, FGFR3, KDR, KIT, PDGFRA, and RET. It is concluded that the combined genomic techniques are necessary to provide a full picture of the patient's genomic alterations. Some of the acquired genomic findings are important for the diagnosis and therapy selection. Germline genomic alterations warrant genetic counseling and are useful for further studies to explore the mechanisms leading to tumorigenesis of MDS patient.
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PMID:[Comprehensive analysis of genomic detection for a patient with myelodysplastic syndrome]. 2437 37