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Identification of small molecules that disrupt signaling between ABL and its positive regulator RIN1.

ABSTRACT: Constitutively active BCR-ABL kinase fusions are causative mutations in the pathogenesis of hematopoietic neoplasias including chronic myelogenous leukemia (CML). Although these fusions have been successfully targeted with kinase inhibitors, drug-resistance and relapse continue to limit long-term survival, highlighting the need for continued innovative drug discovery. We developed a time-resolved Förster resonance energy transfer (TR-FRET) -based assay to identify compounds that disrupt stimulation of the ABL kinase by blocking its ability to bind the positive regulator RIN1. This assay was used in a high throughput screen (HTS) of two small molecule libraries totaling 444,743 compounds. 708 confirmed hits were counter-screened to eliminate off-target inhibitors and reanalyzed to prioritize compounds with IC50 values below 10 μM. The CML cell line K562 was then used to identify five compounds that decrease MAPK1/3 phosphorylation, which we determined to be an indicator of RIN1-dependent ABL signaling. One of these compounds is a thiadiazole, and the other four are structurally related acyl piperidine amides. Notably, these five compounds lower cellular BCR-ABL1 kinase activity by blocking a positive regulatory interaction rather than directly inhibiting ABL catalytic function.

SUBMITTER: Ting PY

PROVIDER: S-EPMC4374917 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Identification of small molecules that disrupt signaling between ABL and its positive regulator RIN1.

Ting Pamela Y PY Damoiseaux Robert R Titz Björn B Bradley Kenneth A KA Graeber Thomas G TG Fernández-Vega Virneliz V Bannister Thomas D TD Chase Peter P Nair Reji R Scampavia Louis L Hodder Peter P Spicer Timothy P TP Colicelli John J

PloS one 20150326 3

Constitutively active BCR-ABL kinase fusions are causative mutations in the pathogenesis of hematopoietic neoplasias including chronic myelogenous leukemia (CML). Although these fusions have been successfully targeted with kinase inhibitors, drug-resistance and relapse continue to limit long-term survival, highlighting the need for continued innovative drug discovery. We developed a time-resolved Förster resonance energy transfer (TR-FRET) -based assay to identify compounds that disrupt stimulat ...[more]

PMID: 25811598

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Identification of small molecules that disrupt signaling between ABL and its positive regulator RIN1.

Publications

Identification of small molecules that disrupt signaling between ABL and its positive regulator RIN1.

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