Neutralization of BCL-2/XL Enhances the Cytotoxicity of T-DM1 In Vivo.
Mol Cancer Ther
; 18(6): 1115-1126, 2019 06.
Article
em En
| MEDLINE
| ID: mdl-30962322
ABSTRACT
One of the most recent advances in the treatment of HER2+ breast cancer is the development of the antibody-drug conjugate, T-DM1. T-DM1 has proven clinical benefits for patients with advanced and/or metastatic breast cancer who have progressed on prior HER2-targeted therapies. However, T-DM1 resistance ultimately occurs and represents a major obstacle in the effective treatment of this disease. Because anti-apoptotic BCL-2 family proteins can affect the threshold for induction of apoptosis and thus limit the effectiveness of the chemotherapeutic payload, we examined whether inhibition of BCL-2/XL would enhance the efficacy of T-DM1 in five HER2-expressing patient-derived breast cancer xenograft models. Inhibition of BCL-2/XL via navitoclax/ABT-263 significantly enhanced the cytotoxicity of T-DM1 in two of three models derived from advanced and treatment-exposed metastatic breast tumors. No additive effects of combined treatment were observed in the third metastatic tumor model, which was highly sensitive to T-DM1, as well as a primary treatment-exposed tumor, which was refractory to T-DM1. A fifth model, derived from a treatment naïve primary breast tumor, was sensitive to T-DM1 but markedly benefited from combination treatment. Notably, both PDXs that were highly responsive to the combination therapy expressed low HER2 protein levels and lacked ERBB2 amplification, suggesting that BCL-2/XL inhibition can enhance sensitivity of tumors with low HER2 expression. Toxicities associated with combined treatments were significantly ameliorated with intermittent ABT-263 dosing. Taken together, these studies provide evidence that T-DM1 cytotoxicity could be significantly enhanced via BCL-2/XL blockade and support clinical investigation of this combination beyond ERBB2-amplified and/or HER2-overexpressed tumors.
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Base de dados:
MEDLINE
Assunto principal:
Sulfonamidas
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Neoplasias da Mama
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Imunoconjugados
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Proteínas Proto-Oncogênicas c-bcl-2
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Citotoxicidade Imunológica
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Proteína bcl-X
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Antineoplásicos Imunológicos
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Ado-Trastuzumab Emtansina
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Compostos de Anilina
Limite:
Animals
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Female
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Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article