Critical Molecular Pathways in Cancer Stem Cells of Chronic Myeloid Leukemia: A Dissertation
Authors
Chen, YaoyuFaculty Advisor
Shaoguang Li M.D., Ph.D.Academic Program
Cancer BiologyUMass Chan Affiliations
MedicineDocument Type
Doctoral DissertationPublication Date
2011-05-11Keywords
LeukemiaMyelogenous
Chronic
BCR-ABL Positive
Neoplastic Stem Cells
5-Lipoxygenase-Activating Proteins
Amino Acids, Peptides, and Proteins
Cancer Biology
Cells
Genetic Phenomena
Hemic and Immune Systems
Neoplasms
Metadata
Show full item recordAbstract
Chronic myeloid leukemia (CML) is a disease characterized by the expansion of granulocytic cells. The BCR-ABL tyrosine kinase inhibitor imatinib, the frontline treatment for Ph+ leukemias, can induce complete hematologic and cytogenetic response in most chronic phase CML patients. Despite the remarkable initial clinic effects, it is now recognized that imatinib will unlikely cure patients because a small cell population containing leukemic stem cells (LSCs) with self-renewal capacity is insensitive to tyrosine kinase inhibitors. In Chapter I, I briefly review the BCR-ABL kinase and its related signaling pathways. BCR-ABL kinase activates several signaling pathways including MAPK, STAT, and JNK/SAPK. BCR-ABL also mediates kinase-independent pathways through SRC family kinases. I will also discuss pathways involving β-catenin, hedgehog, FoxO and Alox5 are critical to the regulation of self-renewal and differentiation in LSC of CML. As detailed in Chapter II, I describe our work evaluating the effects of omacetaxine, a novel CML drug inducing cell apoptosis by inhibition of protein synthesis, on self-renewal and differentiation of LSCs and BCR-ABL-induced CML and acute lymphoblastic leukemia (B-ALL) in mice. We found that treatment with omacetaxine decreased the number of LSCs and prolonged the survival of mice with CML or B-ALL. In chapter III, I describe that Alox5 is an essential gene in the function of LSCs and CML development. We show evidence that Alox5 affects differentiation, cell division, and survival of long-term LSCs. Treatment of CML mice with a 5-LO inhibitor also impaired the function of LSCs similarly and prolonged survival. In chapter IV, I present evidence of our work showing a further dissection the Alox5 pathway by comparing the gene expression profiles of wild type and Alox5-/- LSCs. We show that Msr1 deletion causes acceleration of CML development. We also show that Msr1 affects CML development by regulating the PI3K-AKT pathway and β-catenin. Taken together, these results demonstrate that some pathways including Alox5 and Msr1 play an important role in regulating the self-renewal and differentiation of LSC. More efforts should be put into developing the novel strategies that may effectively target LSCs and thus cure CML.DOI
10.13028/9zxx-3t73Permanent Link to this Item
http://hdl.handle.net/20.500.14038/31875Rights
Copyright is held by the author, with all rights reserved.ae974a485f413a2113503eed53cd6c53
10.13028/9zxx-3t73