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SHR Neuro Krebs Kardio Lipid

Verbrugge, SE; Al, M; Assaraf, YG; Kammerer, S; Chandrupatla, DM; Honeywell, R; Musters, RP; Giovannetti, E; O'Toole, T; Scheffer, GL; Krige, D; de Gruijl, TD; Niessen, HW; Lems, WF; Kramer, PA; Scheper, RJ; Cloos, J; Ossenkoppele, GJ; Peters, GJ; Jansen, G.
Multifactorial resistance to aminopeptidase inhibitor prodrug CHR2863 in myeloid leukemia cells: down-regulation of carboxylesterase 1, drug sequestration in lipid droplets and pro-survival activation ERK/Akt/mTOR.
Oncotarget. 2016; 7(5):5240-5257 [OPEN ACCESS]
Web of Science PubMed PUBMED Central FullText FullText_MUG


Autor/innen der Med Uni Graz:
Kammerer Sarah

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Plum Analytics:
Number of Figures: 7
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Aminopeptidase inhibitors are receiving attention as combination chemotherapeutic agents for the treatment of refractory acute myeloid leukemia. However, the factors determining therapeutic efficacy remain elusive. Here we identified the molecular basis of acquired resistance to CHR2863, an orally available hydrophobic aminopeptidase inhibitor prodrug with an esterase-sensitive motif, in myeloid leukemia cells. CHR2863 enters cells by diffusion and is retained therein upon esterase activity-mediated conversion to its hydrophilic active metabolite drug CHR6768, thereby exerting amino acid depletion. Carboxylesterases (CES) serve as candidate prodrug activating enzymes given CES1 expression in acute myeloid leukemia specimens. We established two novel myeloid leukemia sublines U937/CHR2863(200) and U937/CHR2863(5uM), with low (14-fold) and high level (270-fold) CHR2863 resistance. The latter drug resistant cells displayed: (i) complete loss of CES1-mediated drug activation associated with down-regulation of CES1 mRNA and protein, (ii) marked retention/sequestration of the prodrug, (iii) a substantial increase in intracellular lipid droplets, and (iv) a dominant activation of the pro-survival Akt/mTOR pathway. Remarkably, the latter feature coincided with a gain of sensitivity to the mTOR inhibitor rapamycin. These finding delineate the molecular basis of CHR2863 resistance and offer a novel modality to overcome this drug resistance in myeloid leukemia cells.
Find related publications in this database (using NLM MeSH Indexing)
Aminopeptidases - metabolism
Apoptosis -
Carboxylic Ester Hydrolases - metabolism
Down-Regulation -
Drug Resistance, Neoplasm - genetics
Humans -
Lipid Droplets -
Phosphorylation -
Prodrugs - metabolism
Proto-Oncogene Proteins c-akt - metabolism
TOR Serine-Threonine Kinases - metabolism

Find related publications in this database (Keywords)
lipid droplets
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