In vitro and ex vivo antitumor effect and mechanism of Tucatinib in leukemia stem cells and ABCG2overexpressing leukemia cells.
Oncol Rep
; 45(3): 1142-1152, 2021 03.
Article
em En
| MEDLINE
| ID: mdl-33650639
ABSTRACT
Leukemia stem cells (LSCs), which evade standard chemotherapy, may lead to chemoresistance and disease relapse. The overexpression of ATPbinding cassette subfamily G member 2 (ABCG2) is an important determinant of drug resistance in LSCs and it can serve as a marker for LSCs. Targeting ABCG2 is a potential strategy to selectively treat and eradicate LSCs, and, hence, improve leukemia therapy. Tucatinib (Irbinitinib) is a novel tyrosine kinase inhibitor, targeting ErbB family member HER2, and was approved by the Food and Drug Administration in April 2020, and in Switzerland in May 2020 for the treatment of HER2positive breast cancer. In the present study, the results demonstrated that tucatinib significantly improved the efficacy of conventional chemotherapeutic agents in ABCG2overexpressing leukemia cells and primary leukemia blast cells, derived from patients with leukemia. In addition, tucatinib markedly decreased the proportion of leukemia stem celllike side population (SP) cells. In SP cells, isolated from leukemia cells, the intracellular accumulation of Hoechst 33342, which is an ABCG2 substrate, was significantly elevated by tucatinib. Furthermore, tucatinib notably inhibited the efflux of [3H]mitoxantrone and, hence, there was a higher level of [3H]mitoxantrone in the HL60/ABCG2 cell line. The result from the ATPase assay revealed that tucatinib may interact with the drug substratebinding site and stimulated ATPase activity of ABCG2. However, the protein expression level and cellular location of ABCG2 were not affected by tucatinib treatment. Taken together, these data suggested that tucatinib could sensitize conventional chemotherapeutic agents, in ABCG2overexpressing leukemia cells and LSCs, by blocking the pump function of the ABCG2 protein. The present study revealed that combined treatment with tucatinib and conventional cytotoxic agents could be a potential therapeutic strategy in ABCG2positive leukemia.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxazóis
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Piridinas
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Quinazolinas
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Células-Tronco Neoplásicas
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Leucemia
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Células da Side Population
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Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP
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Proteínas de Neoplasias
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Antineoplásicos
Limite:
Adult
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Female
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Humans
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Male
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article