Ontology highlight
ABSTRACT: Purpose
The clinical relevance of targeting the RAS/RAF/MEK/ERK pathway, activated in 70% to 80% of patients with acute myelogenous leukemia (AML), is unknown.Experimental design
Selumetinib is an oral small-molecule inhibitor of MAP-ERK kinase (MEK)-1/2. Forty-seven patients with relapsed/refractory AML or 60 years old or more with untreated AML were enrolled on a phase II study. Patients were stratified by FLT3 ITD mutation status. The primary endpoint was response rate (complete, partial, and minor). Leukemia cells were analyzed for extracellular signal-regulated kinase (ERK) and mTOR phosphorylation.Results
Common drug-related toxicities were grade 1-2 diarrhea, fatigue, nausea, vomiting, and skin rash. In the FLT3 wild-type cohort, six of 36 (17%) patients had a response [one partial response, three minor responses, two unconfirmed minor responses (uMR)]. No patient with FLT3 ITD responded. NRAS and KRAS mutations were detected in 7% and 2% of patients, respectively. The sole patient with KRAS mutation had uMR with hematologic improvement in platelets. Baseline p-ERK activation was observed in 85% of patients analyzed but did not correlate with a response. A single-nucleotide polymorphism (SNP) rs3733542 in exon 18 of the KIT gene was detected in significantly higher number of patients with response/stable disease compared with nonresponders (60% vs. 23%; P = 0.027).Conclusions
Selumetinib is associated with modest single-agent antileukemic activity in advanced AML. However, given its favorable toxicity profile, combination with drugs that target other signaling pathways in AML should be considered. The potential association of SNP rs3733542 in exon 18 of the KIT gene with antileukemic activity of selumetinib is intriguing, but will require validation in larger trials.
SUBMITTER: Jain N
PROVIDER: S-EPMC4310865 | biostudies-literature | 2014 Jan
REPOSITORIES: biostudies-literature
Jain Nitin N Curran Emily E Iyengar Neil M NM Diaz-Flores Ernesto E Kunnavakkam Rangesh R Popplewell Leslie L Kirschbaum Mark H MH Karrison Theodore T Erba Harry P HP Green Margaret M Poire Xavier X Koval Greg G Shannon Kevin K Reddy Poluru L PL Joseph Loren L Atallah Ehab L EL Dy Philip P Thomas Sachdev P SP Smith Scott E SE Doyle L Austin LA Stadler Walter M WM Larson Richard A RA Stock Wendy W Odenike Olatoyosi O
Clinical cancer research : an official journal of the American Association for Cancer Research 20131031 2
<h4>Purpose</h4>The clinical relevance of targeting the RAS/RAF/MEK/ERK pathway, activated in 70% to 80% of patients with acute myelogenous leukemia (AML), is unknown.<h4>Experimental design</h4>Selumetinib is an oral small-molecule inhibitor of MAP-ERK kinase (MEK)-1/2. Forty-seven patients with relapsed/refractory AML or 60 years old or more with untreated AML were enrolled on a phase II study. Patients were stratified by FLT3 ITD mutation status. The primary endpoint was response rate (comple ...[more]