title: Drug resistance and methylation in myelodysplastic syndrome.
abstract: Myelodysplastic syndrome is a clonal hematopoietic stem cell disorder that presents a poor survival for patients treated with standard therapies other than stem-cell transplantation. Multi-drug resistance (MDR) to simultaneous drugs used in chemotherapy is a major concern in the treatment of cancer and also in MDS. ATP-binding cassette (ABC) transporters are involved in the main mechanism that confers drug resistance to cells. Increased expression of drug resistance genes, such as MDR1, MRP1 and LRP, is involved with multi-drug resistance in MDS. The expression of these drug efflux transporters acts in synergy with other alterations, such as epigenetic events, increases in multidrug resistance in MDS. Methylation, the main epigenetic mechanism is widely explored in other hematological malignancies; however, in MDS, this mechanism is poorly investigated. Clinical trials evaluated or are under ongoing evaluation of drugs that abrogated ABC transporters action or reversed the abnormal methylation of some genes in MDS. In this report, we explore the data available in the field of drug resistance and methylation both in pediatric and adult MDS.
authors: Laboratory of Molecular Biology and Genomics, Ludwig Institute for Cancer Research--São Paulo Branch, Brazil. dvidal@ludwig.org.br
authors: D O
authors: DO
authors: Vidal
authors: L F
authors: LF
authors: Lopes
authors: E T
authors: ET
authors: Valera
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D019175:DNA Methylation / Q000187:drug effects*; D004351:Drug Resistance / Q000187:drug effects*; D006801:Humans; D009190:Myelodysplastic Syndromes / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology*; D011379:Prognosis
chemical_list: D018528:ATP-Binding Cassette Transporters; D000970:Antineoplastic Agents