• Media type: E-Article
  • Title: Targeting JAK1/2 and mTOR in murine xenograft models of Ph-like acute lymphoblastic leukemia
  • Contributor: Maude, Shannon L.; Tasian, Sarah K.; Vincent, Tiffaney; Hall, Junior W.; Sheen, Cecilia; Roberts, Kathryn G.; Seif, Alix E.; Barrett, David M.; Chen, I-Ming; Collins, J. Racquel; Mullighan, Charles G.; Hunger, Stephen P.; Harvey, Richard C.; Willman, Cheryl L.; Fridman, Jordan S.; Loh, Mignon L.; Grupp, Stephan A.; Teachey, David T.
  • Published: American Society of Hematology, 2012
  • Published in: Blood, 120 (2012) 17, Seite 3510-3518
  • Language: English
  • DOI: 10.1182/blood-2012-03-415448
  • ISSN: 0006-4971; 1528-0020
  • Origination:
  • Footnote:
  • Description: Abstract CRLF2 rearrangements, JAK1/2 point mutations, and JAK2 fusion genes have been identified in Philadelphia chromosome (Ph)–like acute lymphoblastic leukemia (ALL), a recently described subtype of pediatric high-risk B-precursor ALL (B-ALL) which exhibits a gene expression profile similar to Ph-positive ALL and has a poor prognosis. Hyperactive JAK/STAT and PI3K/mammalian target of rapamycin (mTOR) signaling is common in this high-risk subset. We, therefore, investigated the efficacy of the JAK inhibitor ruxolitinib and the mTOR inhibitor rapamycin in xenograft models of 8 pediatric B-ALL cases with and without CRLF2 and JAK genomic lesions. Ruxolitinib treatment yielded significantly lower peripheral blast counts compared with vehicle (P < .05) in 6 of 8 human leukemia xenografts and lower splenic blast counts (P < .05) in 8 of 8 samples. Enhanced responses to ruxolitinib were observed in samples harboring JAK-activating lesions and higher levels of STAT5 phosphorylation. Rapamycin controlled leukemia burden in all 8 B-ALL samples. Survival analysis of 2 representative B-ALL xenografts demonstrated prolonged survival with rapamycin treatment compared with vehicle (P < .01). These data demonstrate preclinical in vivo efficacy of ruxolitinib and rapamycin in this high-risk B-ALL subtype, for which novel treatments are urgently needed, and highlight the therapeutic potential of targeted kinase inhibition in Ph-like ALL.
  • Access State: Open Access