TY - JOUR
T1 - A high-throughput fluorimetric assay for 2-Hydroxyglutarate Identifies Zaprinast as a Glutaminase Inhibitor
AU - Elhammali, Adnan
AU - Ippolito, Joseph E.
AU - Collins, Lynne
AU - Crowley, Jan
AU - Marasa, Jayne
AU - Piwnica-Worms, David
PY - 2014/7
Y1 - 2014/7
N2 - Recently identified isocitrate dehydrogenase (IDH) mutations lead to the production of 2-hydroxyglutarate (2HG), an oncometabolite aberrantly elevated in selected cancers. We developed a facile and inexpensive fluorimetric microplate assay for the quantitation of 2HG and performed an unbiased small-molecule screen in live cells to identify compounds capable of perturbing 2HG production. Zaprinast, a phosphodiesterase 5 inhibitor, was identified as an efficacious modulator of 2HG production and confirmed to lower 2HG levels in vivo. The mechanism of action was not due to cGMP stabilization, but rather, profiling of metabolites upstream of mutant IDH1 pointed to targeted inhibition of the enzyme glutaminase (GLS). Zaprinast treatment reversed histone hypermethylation and soft-agar growth of IDH1-mutant cells, and treatment of glutamine-addicted pancreatic cancer cells reduced growth and sensitized cells to oxidative damage. Thus, Zaprinast is efficacious against glutamine metabolism and further establishes the therapeutic linkages between GLS and 2HG-mediated oncogenesis.
AB - Recently identified isocitrate dehydrogenase (IDH) mutations lead to the production of 2-hydroxyglutarate (2HG), an oncometabolite aberrantly elevated in selected cancers. We developed a facile and inexpensive fluorimetric microplate assay for the quantitation of 2HG and performed an unbiased small-molecule screen in live cells to identify compounds capable of perturbing 2HG production. Zaprinast, a phosphodiesterase 5 inhibitor, was identified as an efficacious modulator of 2HG production and confirmed to lower 2HG levels in vivo. The mechanism of action was not due to cGMP stabilization, but rather, profiling of metabolites upstream of mutant IDH1 pointed to targeted inhibition of the enzyme glutaminase (GLS). Zaprinast treatment reversed histone hypermethylation and soft-agar growth of IDH1-mutant cells, and treatment of glutamine-addicted pancreatic cancer cells reduced growth and sensitized cells to oxidative damage. Thus, Zaprinast is efficacious against glutamine metabolism and further establishes the therapeutic linkages between GLS and 2HG-mediated oncogenesis.
UR - http://www.scopus.com/inward/record.url?scp=84904042360&partnerID=8YFLogxK
U2 - 10.1158/2159-8290.CD-13-0572
DO - 10.1158/2159-8290.CD-13-0572
M3 - Article
C2 - 24740997
AN - SCOPUS:84904042360
SN - 2159-8274
VL - 4
SP - 828
EP - 839
JO - Cancer discovery
JF - Cancer discovery
IS - 7
ER -