상세정보
Export to Refworks부가기능
Non-chemotherapeutic Methods of Treating T Cell Acute Lymphoblastic Leukemia
상세 프로파일
| 자료유형 | 학위논문 |
|---|---|
| 서명/저자사항 | Non-chemotherapeutic Methods of Treating T Cell Acute Lymphoblastic Leukemia. |
| 개인저자 | Walker, Kirsti L. |
| 단체저자명 | The University of Wisconsin - Madison. Cellular & Molecular Pathology. |
| 발행사항 | [S.l.]: The University of Wisconsin - Madison., 2019. |
| 발행사항 | Ann Arbor: ProQuest Dissertations & Theses, 2019. |
| 형태사항 | 186 p. |
| 기본자료 저록 | Dissertations Abstracts International 81-04B. Dissertation Abstract International |
| ISBN | 9781687938978 |
| 학위논문주기 | Thesis (Ph.D.)--The University of Wisconsin - Madison, 2019. |
| 일반주기 |
Source: Dissertations Abstracts International, Volume: 81-04, Section: B.
Advisor: Capitini, Christian M. |
| 이용제한사항 | This item must not be sold to any third party vendors. |
| 요약 | Relapsed/refractory T-cell acute lymphoblastic leukemia (T-ALL) is difficult to salvage with current chemotherapy regimens, but achieving complete remission is essential for allogeneic bone marrow transplants to cure patients. Chemotherapy is the first-line treatment for relapsed/refractory T-ALL patients, but presently used regimens lead to only 23% 5-year event-free survival. In addition, chemotherapy results in long-term toxicity and can be fatal due to increased risks of infection and other complications. Therefore, there is a need for the development of non-chemotherapeutic treatment strategies for T-ALL. In Chapters I and II, two signaling pathways, the JAK/STAT and BCL2 pathway are demonstrated to be upregulated in T-ALL to promote increased T-ALL proliferation and survival. Ruxolitinib is a small molecule inhibitor of the JAK/STAT pathway, while venetoclax is a potent BCL2 inhibitor. The overriding hypothesis of chapter II was that dual inhibition of the JAK/STAT and BCL2 pathways with ruxolitinib and venetoclax would be synergistic, resulting in maximal T-ALL cell death. In vitro experiments demonstrate that ruxolitinib and venetoclax combination treatment synergistically reduces survival and proliferation of Jurkat T-ALL and Loucy early T cell precursor (ETP)-ALL cells. I then developed a T-ALL xenograft model using Jurkat cells into immunocompromised NOD-SCID-[Special character(s) omitted]c-/- (NSG) mice. Surprisingly, the robust anti-leukemia effect seen in vitro did not translate in vivo due to homing of the Jurkat cells into the central nervous system (CNS). Because it was unknown if either ruxolitinib or venetoclax could cross the blood-brain barrier (BBB), Liquid chromatography - tandem mass spectrometry (LC-MS-MS) of whole NSG mice brains and spinal cords was performed following ruxolitinib or venetoclax treatment. This experiment indicated that subtherapeutic amounts of 50 mg/kg ruxolitinib can cross the BBB and pentrate the brain and spinal cord tissue and subtherapeutic amounts of 100 mg/kg venetoclax can be detected in the spinal cord. This observation may have explained why the lower synergistic doses used in our experimental model (30 mg/kg/day ruxolitinib and 35 mg/kg/day venetoclax) were ineffective against the CNS T-ALL burden seen in the brain and spinal cord. I next investigated a possible mechanism by which T-ALL could escape from systemic treatment with ruxolitinib and venetoclax by trafficking into the CNS. It was previously demonstrated that CXCR4 expression was required to initiate leukemia cell activity, as well as regulate migration and homing of T-ALL into its target organs, including the CNS. It has also been demonstrated that CXCL12 produced from vascular endothelial niches controls T-ALL maintenance, suggesting the CXCR4-CXCL12 pathway regulated T-ALL escape into the CNS. CRISPR-Cas9 deletion of CXCR4 from Jurkat cells was performed, and after tumor challenge in NSG mice, demonstrated prolonged survival and reduced overall and neurological clinical scores in vivo, demonstrating the critical role this receptor plays in T-ALL progression. In chapter III, I investigated if there was a way to target CNS T-ALL tumor burden with the use of adoptive cell therapy. Using human NK cells expanded and activated ex vivo with IL-15 and CD137L expressing artificial antigen presenting cells, I was able to demonstrate that these ex vivo expanded and activated NK cells can be produced in high enough numbers to allow for infusion of fresh and cryopreserved doses for future use. Further, these cryopreserved batches were thawed and demonstrated similar expression of NKG2D and Granzyme B as well as potent ADCC compared to fresh ex vivo expanded NK cells. Ruxolitinib treatment of ex vivo expanded and activated fresh NK cells abrogated gamma interferon secretion, but had no effect on cryopreserved NK cells. These observations suggest that usage of fresh or cryopreserved/thawed ex vivo expanded NK cells could a therapeutic option that could be combined with ruxolitinib and venetoclax treatment to treat systemic and CNS T-ALL disease.Collectively, this thesis demonstrates the potential of using ruxolitinib and venetoclax as a non-chemotherapeutic means to target T-ALL, with further investigation required in vivo. This thesis demonstrates the limitations of ruxolitinib and venetoclax to effectively cross the BBB and penetrate tissue of the CNS. This study also confirms that the CXCR4-CXCL12 pathway in Jurkat cells is necessary for regulating T-ALL progression in an NSG mouse model, but deletion of CXCR4 was not sufficient in preventing the eventual lethality of the disease. In conclusion, ruxolitinib and venetoclax could potentially be combined with either inhibitors of CXCR4, or adoptive cell therapy with ex vivo expanded and activated NK cells, to target primary CNS disease or prevent CNS relapse of T-ALL. |
| 일반주제명 | Immunology. Biology. |
| 언어 | 영어 |
| 바로가기 | 
: 이 자료의 원문은 한국교육학술정보원에서 제공합니다. |
