HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Mechanisms of resistance to azacitidine in human leukemia cell lines.

Abstract
The DNA methylation inhibitor azacitidine (5-azacytidine) is used against myelodysplastic syndrome and acute myeloid leukemia, but drug resistance is an ongoing, intractable problem. To investigate resistance mechanisms, we generated two azacitidine-resistant cell lines, THP-1/AR and HL60/AR, and studied genetic disparities between them and their corresponding parental lines. In cells treated with azacitidine, significant mitotic variations were noted in parental cells which were absent in resistant cells, suggesting that resistance arises from negating azacitidine-mediated activation of apoptosis signaling and reestablishing G2/M checkpoint. Importantly, both resistant cell lines have common point mutations in the uridine-cytidine kinase 2 (UCK2) gene, which encodes the rate-limiting enzyme of the azacitidine activation pathway. Forced expression of mutated UCK2 in parental THP-1 cells abrogated azacitidine-induced apoptosis, whereas overexpression of wild type UCK2 in resistant THP-1/AR cells restored sensitivity to azacitidine, implying that UCK2 gene mutations perturb azacitidine activation and advance azacitidine resistance. Our study provides new insights into azacitidine resistance and establishes models useful in developing effective strategies to overcome it.
AuthorsPiyanuch Sripayap, Tadashi Nagai, Mitsuyo Uesawa, Hiroyuki Kobayashi, Tomonori Tsukahara, Ken Ohmine, Kazuo Muroi, Keiya Ozawa
JournalExperimental hematology (Exp Hematol) Vol. 42 Issue 4 Pg. 294-306.e2 (Apr 2014) ISSN: 1873-2399 [Electronic] Netherlands
PMID24368162 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
CopyrightCopyright © 2014 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.
Chemical References
  • Antimetabolites, Antineoplastic
  • UCK2 protein, human
  • Uridine Kinase
  • Azacitidine
Topics
  • Antimetabolites, Antineoplastic (pharmacology)
  • Azacitidine (pharmacology)
  • Cell Division (drug effects, genetics)
  • Drug Resistance, Neoplasm (drug effects, genetics)
  • G2 Phase (drug effects, genetics)
  • HL-60 Cells
  • Humans
  • Leukemia, Myeloid
  • Point Mutation
  • Uridine Kinase (genetics, metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: