A Phenotypic Screen for Small-Molecule Inhibitors of Constitutively Active Mutant Thrombopoietin Receptor Implicated in Myeloproliferative Neoplasms

Title:A Phenotypic Screen for Small-Molecule Inhibitors of Constitutively Active Mutant Thrombopoietin Receptor Implicated in Myeloproliferative Neoplasms

Volume: 19 Issue: 10

Author(s): Anna Ngo, Ann Zhufang Koay, Christian Pecquet, Carmen C. Diaconu, Yasmine Ould-Amer, Qiwei Huang, Congbao Kang, Anders Poulsen, May Ann Lee, David Jenkins, Andrew Shiau, Stefan N. Constantinescu and Meng Ling Choong

Affiliation:

Keywords: Myeloproliferative neoplasms, thrombopoietin receptor, G protein-coupled receptor, phenotypic screening, drug combination study, Janus Kinase 2.

Abstract: Background: Rather than a Janus Kinase 2 inhibitor (ruxolitinib), a specific thrombopoietin receptor (TpoR) inhibitor would be more specific for the treatment of myeloproliferative neoplasms due to TpoR mutations.

Objective: A cell-based phenotypic approach to identify specific TpoR inhibitors was implemented and a library of 505,483 small molecules was screened for inhibitory effects on cells transformed by TpoR mutants.

Results: Among the identified hits are two analogs of 3-(4-piperidinyl) indole. The analogs showed about five-fold preferential inhibition of cell viability towards Ba/F3 cells expressing the TpoR W515L mutation compared to the parental cells. There was no significant difference in inhibition of cell viability between the TpoR wild type and the TpoR W515L mutant cells. Preferential inhibition of viability was observed in Ba/F3 cells expressing erythropoietin receptor (EpoR) when stimulated with Epo compared to stimulation with interleukin-3 (IL3). The indole analog inhibited ex vivo colony formations of primary bone marrow cells from heterozygous JAK2 V617F knock-in mice. Drug combination treatment study was performed using ruxolitinib and the indole analog. Drug synergistic effects were observed when cells were stimulated to proliferate through both the IL3 and TpoR pathways. Our compound specifically targets monoamine receptors in the rhodopsin-like receptor family of G protein-coupled receptor.

Conclusion: This screen has identified a monoamine receptor inhibitor that can inhibit viability of cells with active TpoR or EpoR signalings. Drug synergism with ruxolitib is demonstrated.

Cite this article as:

Ngo Anna, Koay Zhufang Ann, Pecquet Christian, Diaconu C. Carmen, Ould-Amer Yasmine, Huang Qiwei, Kang Congbao, Poulsen Anders, Lee Ann May, Jenkins David, Shiau Andrew, Constantinescu N. Stefan and Choong Ling Meng, A Phenotypic Screen for Small-Molecule Inhibitors of Constitutively Active Mutant Thrombopoietin Receptor Implicated in Myeloproliferative Neoplasms, Combinatorial Chemistry & High Throughput Screening 2016; 19 (10) . https://dx.doi.org/10.2174/1386207319666161010163825

DOI https://dx.doi.org/10.2174/1386207319666161010163825	Print ISSN 1386-2073
Publisher Name Bentham Science Publisher	Online ISSN 1875-5402