Chromosomal translocation t(9;22) is responsible for appearance of an oncogene encoding BCR/ABL fusion tyrosine kinase, which induce chronic myelogenous leukemia (CML) and a cohort of acute lymphocytic leukemia (ALL). CML usually starts as a relatively benign chronic phase (CML-CP), which progresses to an aggressive disease - blast crisis (CML-BC). Malignant transformation of the disease is associated with accumulation of additional genetic errors. Imatinib mesylate (IM), a small molecule inhibitor of BCR/ABL kinase, revolutionized the treatment of CML-CP. Unfortunately patients may develop resistance to the drug caused by point mutations encoding amino acid substitutions in the BCR/ABL kinase domain. In conclusion, CML cells display genomic instability leading to resistance to IM and malignant progression of the disease. This proposal is focused on determination the mechanisms responsible for these phenomena and subsequently on prevention/inhibition of the development of IM resistance and CML-BC. BCR/ABL kinase stimulates numerous signaling pathways to induce and maintain transformation of hematopoietic cells. We, and others found that phosphatidylinositol-3 kinase (PI-3k) play an essential role in growth factor independent proliferation and protection from apoptosis in CML. Here we propose to study the role of PI-3k and its downstream effectors Akt and Rac in genomic instability in CML stem and progenitor cell populations. Using genetic approach (dominant-negative mutants, siRNA, antisense cDNA, knockout mice) and small molecule inhibitors (for example perifosine, NSC23766) we will determine how PI-3k and its downstream effectors generate the reactive oxygen species (ROS), which in turn may cause oxidative DNA damage and facilitate genomic instability. Long-term in vitro culture and mouse models of CML will be applied here. IM resistance will be detected in clonogenic assays and by sequencing BCR/ABL kinase domain, and chromosomal aberrations will be detected by SNPs and SKY. If successfully accomplished, these experiments will determine if PI-3k pathway inhibitors should be used to improve therapeutic effect of IM and prevent/delay CML progression toward lethal blast crisis.

Public Health Relevance

Although tyrosine kinase inhibitors (TKIs) revolutionized the treatment of chronic myelogenous leukemia (CML), patients can develop resistance to the drug and progress toward fatal malignant blast crisis of the disease. Both phenomena are associated with genetic instability caused by oncogenic BCR/ABL kinase. We will investigate the mechanisms responsible for mutations in BCR/ABL kinase causing TKI-resistance and for chromosomal aberrations leading to blast crisis. Molecular mechanisms of BCR/ABL-dependent phosphatidylinositol (PI-3k)-mediated production of reactive oxygen species (ROS) causing oxidative DNA damage, mutations, and chromosomal aberrations will be determined.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA134458-03
Application #
8271268
Study Section
Basic Mechanisms of Cancer Therapeutics Study Section (BMCT)
Program Officer
Mufson, R Allan
Project Start
2010-07-01
Project End
2015-05-31
Budget Start
2012-06-01
Budget End
2013-05-31
Support Year
3
Fiscal Year
2012
Total Cost
$307,951
Indirect Cost
$106,676
Name
Temple University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
057123192
City
Philadelphia
State
PA
Country
United States
Zip Code
19122
Maifrede, Silvia; Nieborowska-Skorska, Margaret; Sullivan-Reed, Katherine et al. (2018) Tyrosine kinase inhibitor-induced defects in DNA repair sensitize FLT3(ITD)-positive leukemia cells to PARP1 inhibitors. Blood 132:67-77
Nieborowska-Skorska, Margaret; Sullivan, Katherine; Dasgupta, Yashodhara et al. (2017) Gene expression and mutation-guided synthetic lethality eradicates proliferating and quiescent leukemia cells. J Clin Invest 127:2392-2406
Maifrede, Silvia; Martinez, Esteban; Nieborowska-Skorska, Margaret et al. (2017) MLL-AF9 leukemias are sensitive to PARP1 inhibitors combined with cytotoxic drugs. Blood Adv 1:1467-1472
Nieborowska-Skorska, Margaret; Maifrede, Silvia; Dasgupta, Yashodhara et al. (2017) Ruxolitinib-induced defects in DNA repair cause sensitivity to PARP inhibitors in myeloproliferative neoplasms. Blood 130:2848-2859
Podszywalow-Bartnicka, Paulina; Cmoch, Anna; Wolczyk, Magdalena et al. (2016) Increased phosphorylation of eIF2? in chronic myeloid leukemia cells stimulates secretion of matrix modifying enzymes. Oncotarget 7:79706-79721
Dasgupta, Yashodhara; Koptyra, Mateusz; Hoser, Grazyna et al. (2016) Normal ABL1 is a tumor suppressor and therapeutic target in human and mouse leukemias expressing oncogenic ABL1 kinases. Blood 127:2131-43
Sullivan, Katherine; Cramer-Morales, Kimberly; McElroy, Daniel L et al. (2016) Identification of a Small Molecule Inhibitor of RAD52 by Structure-Based Selection. PLoS One 11:e0147230
Synowiec, Ewelina; Hoser, Grazyna; Wojcik, Katarzyna et al. (2015) UV Differentially Induces Oxidative Stress, DNA Damage and Apoptosis in BCR-ABL1-Positive Cells Sensitive and Resistant to Imatinib. Int J Mol Sci 16:18111-28
Synowiec, Ewelina; Hoser, Grazyna; Bialkowska-Warzecha, Jolanta et al. (2015) Doxorubicin Differentially Induces Apoptosis, Expression of Mitochondrial Apoptosis-Related Genes, and Mitochondrial Potential in BCR-ABL1-Expressing Cells Sensitive and Resistant to Imatinib. Biomed Res Int 2015:673512
Nieborowska-Skorska, M; Flis, S; Skorski, T (2014) AKT-induced reactive oxygen species generate imatinib-resistant clones emerging from chronic myeloid leukemia progenitor cells. Leukemia 28:2416-8

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