ON 01910.Na is selectively cytotoxic for chronic lymphocytic leukemia cells through a dual mechanism of action involving PI3K/AKT inhibition and induction of oxidative stress

• Published in: Clinical cancer research 2012-04, Vol.18 (7), p.1979-1991
• Main Authors: Chapman, Colby M, Sun, Xiameng, Roschewski, Mark, Aue, Georg, Farooqui, Mohamed, Stennett, Lawrence, Gibellini, Federica, Arthur, Diane, Pérez-Galán, Patricia, Wiestner, Adrian
• Format: Article
• Language: English
• Subjects: 1-Phosphatidylinositol 3-kinase; Activating Transcription Factor 3 - genetics; Activating Transcription Factor 3 - metabolism; AKT protein; Annexin V; Apoptosis; Apoptosis - drug effects; Blotting, Western; c-Jun amino-terminal kinase; Cancer; CD19 antigen; Cell Line, Tumor; Cell survival; Chemotherapy; Chronic lymphatic leukemia; Clinical trials; Cytotoxicity; Data processing; Dendritic cells; DNA microarrays; Female; Flow cytometry; Gene expression; Gene Expression Profiling; Glycine - analogs & derivatives; Glycine - pharmacology; HEK293 Cells; HL-60 Cells; Humans; Immunoglobulin Heavy Chains - genetics; Immunoglobulin Variable Region - genetics; Immunoglobulins; Leukemia, Lymphocytic, Chronic, B-Cell - genetics; Leukemia, Lymphocytic, Chronic, B-Cell - metabolism; Leukemia, Lymphocytic, Chronic, B-Cell - pathology; Leukocyte migration; Lymphocytes B; Lymphocytes T; Male; Malignancy; Membrane Potential, Mitochondrial - drug effects; Microenvironments; Mutation; Myelodysplastic syndrome; Oligonucleotide Array Sequence Analysis; Oxidative stress; Oxidative Stress - drug effects; Phosphatidylinositol 3-Kinases - genetics; Phosphatidylinositol 3-Kinases - metabolism; Proto-Oncogene Proteins c-akt - genetics; Proto-Oncogene Proteins c-akt - metabolism; Proto-Oncogene Proteins c-bcl-2 - genetics; Proto-Oncogene Proteins c-bcl-2 - metabolism; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference; Signal Transduction - drug effects; Stroma; Sulfones - pharmacology; Toxicity; Tumor Cells, Cultured; Tumors; Variable region; Western blotting
• ISSN: 1078-0432; 1557-3265; 1078-0432
• DOI: 10.1158/1078-0432.CCR-11-2113

Chronic lymphocytic leukemia (CLL), a malignancy of mature B cells, is incurable with chemotherapy. Signals from the microenvironment support leukemic cell survival and proliferation and may confer chemotherapy resistance. ON 01910.Na (Rigosertib), a multikinase phosphoinositide 3-kinase (PI3K) inhibitor, is entering phase III trials for myelodysplastic syndrome. Our aim was to analyze the efficacy of ON 01910.Na against CLL cells in vitro and investigate the molecular effects of this drug on tumor biology. Cytotoxicity of ON 01910.Na against CLL cells from 34 patients was determined in vitro with flow cytometry of cells stained with Annexin V and CD19. Global gene expression profiling on Affymetrix microarrays, flow cytometry, Western blotting, and cocultures with stroma cells were used to delineate ON 01910.Na mechanism of action. ON 01910.Na induced apoptosis in CLL B cells without significant toxicity against T cells or normal B cells. ON 01910.Na was equally active against leukemic cells associated with a more aggressive disease course [immunoglobulin heavy-chain variable region unmutated, adverse cytogenetics] than against cells without these features. Gene expression profiling revealed two main mechanisms of action: PI3K/AKT inhibition and induction of ROS that resulted in an oxidative stress response through activating protein 1 (AP-1), c-jun-NH(2)-terminal kinase, and ATF3 culminating in the upregulation of NOXA. ROS scavengers and shRNA mediated knockdown of ATF3- and NOXA-protected cells from drug-induced apoptosis. ON 01910.Na also abrogated the prosurvival effect of follicular dendritic cells on CLL cells and reduced SDF-1-induced migration of leukemic cells. These data support the clinical development of ON 01910.Na in CLL.