In vitro efficacy of forodesine and nelarabine (ara-G) in pediatric leukemia

Blood. 2011 Aug 25;118(8):2184-90. doi: 10.1182/blood-2011-02-337840. Epub 2011 Jul 5.

Abstract

Forodesine and nelarabine (the pro-drug of ara-G) are 2 nucleoside analogues with promising anti-leukemic activity. To better understand which pediatric patients might benefit from forodesine or nelarabine (ara-G) therapy, we investigated the in vitro sensitivity to these drugs in 96 diagnostic pediatric leukemia patient samples and the mRNA expression levels of different enzymes involved in nucleoside metabolism. Forodesine and ara-G cytotoxicities were higher in T-cell acute lymphoblastic leukemia (T-ALL) samples than in B-cell precursor (BCP)-ALL and acute myeloid leukemia (AML) samples. Resistance to forodesine did not preclude ara-G sensitivity and vice versa, indicating that both drugs rely on different resistance mechanisms. Differences in sensitivity could be partly explained by significantly higher accumulation of intracellular dGTP in forodesine-sensitive samples compared with resistant samples, and higher mRNA levels of dGK but not dCK. The mRNA levels of the transporters ENT1 and ENT2 were higher in ara-G-sensitive than -resistant samples. We conclude that especially T-ALL, but also BCP-ALL, pediatric patients may benefit from forodesine or nelarabine (ara-G) treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / therapeutic use*
  • Arabinonucleosides / therapeutic use*
  • Cell Line, Tumor
  • Child
  • Deoxycytidine Kinase / genetics
  • Deoxyguanine Nucleotides / metabolism
  • Drug Resistance, Neoplasm
  • Equilibrative Nucleoside Transporter 1 / genetics
  • Equilibrative-Nucleoside Transporter 2 / genetics
  • Gene Expression
  • Humans
  • In Vitro Techniques
  • Leukemia, Myeloid, Acute / drug therapy*
  • Leukemia, Myeloid, Acute / genetics
  • Leukemia, Myeloid, Acute / metabolism
  • Leukemia, Prolymphocytic, B-Cell / drug therapy*
  • Leukemia, Prolymphocytic, B-Cell / genetics
  • Leukemia, Prolymphocytic, B-Cell / metabolism
  • Phosphotransferases (Alcohol Group Acceptor) / genetics
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / drug therapy*
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / genetics
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / metabolism
  • Prodrugs / therapeutic use*
  • Purine Nucleosides / therapeutic use*
  • Purines / metabolism
  • Pyrimidinones / therapeutic use*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Neoplasm / genetics
  • RNA, Neoplasm / metabolism

Substances

  • Antineoplastic Agents
  • Arabinonucleosides
  • Deoxyguanine Nucleotides
  • Equilibrative Nucleoside Transporter 1
  • Equilibrative-Nucleoside Transporter 2
  • Prodrugs
  • Purine Nucleosides
  • Purines
  • Pyrimidinones
  • RNA, Messenger
  • RNA, Neoplasm
  • SLC29A1 protein, human
  • SLC29A2 protein, human
  • 9-arabinofuranosylguanine
  • forodesine
  • nelarabine
  • deoxyguanosine triphosphate
  • Phosphotransferases (Alcohol Group Acceptor)
  • deoxyguanosine kinase
  • Deoxycytidine Kinase