LW106, a novel indoleamine 2,3-dioxygenase 1 inhibitor, suppresses tumour progression by limiting stroma-immune crosstalk and cancer stem cell enrichment in tumour micro-environment.
Br J Pharmacol
; 175(14): 3034-3049, 2018 07.
Article
em En
| MEDLINE
| ID: mdl-29722898
ABSTRACT
BACKGROUND AND PURPOSE:
Indoleamine 2,3-dioxygenase 1 (IDO1) is emerging as an important new therapeutic target for treatment of malignant tumours characterized by dysregulated tryptophan metabolism. However, the antitumour efficacy of existing small-molecule inhibitors of IDO1 is still unsatisfactory and the underlying mechanism remains largely undefined. Hence, we discovered a novel potent small-molecule inhibitor of IDO1, LW106, and studied its antitumour effects and the underlying mechanisms in two tumour models. EXPERIMENTALAPPROACH:
C57BL6 mice, athymic nude mice or Ido1-/- mice were inoculated with IDO1-expressing and -nonexpressing tumour cells and treated with vehicle, epacadostat or increasing doses of LW106. Xenografted tumours, plasma, spleens and other vital organs were harvested and subjected to kynurenine/tryptophan measurement and flow cytometric, histological and immunohistochemical analyses. KEYRESULTS:
LW106 dose-dependently inhibited the outgrowth of xenografted tumours that were inoculated in C57BL6 mice but not nude mice or Ido1-/- mice, showing a stronger antitumour efficacy than epacadostat, an existing IDO1 inhibitor. LW106 substantially elevated intratumoural infiltration of proliferative Teff cells, while reducing recruitment of proliferative Treg cells and non-haematopoietic stromal cells such as endothelial cells and cancer-associated fibroblasts. LW106 treatment resulted in a reduced subpopulation of cancer stem cells (CSCs) in xenografted tumours in which fewer proliferative/invasive tumour cells and more apoptotic tumour cells were observed. CONCLUSIONS AND IMPLICATIONS LW106 inhibits tumour outgrowth by limiting stroma-immune crosstalk and CSC enrichment in the tumour micro-environment. LW106 has potential as a immunotherapeutic agent for use in combination with immune checkpoint inhibitors and (or) chemotherapeutic drugs for cancer treatment.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Dioxigenases
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Neoplasias
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Antineoplásicos
Limite:
Animals
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Humans
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Male
Idioma:
En
Revista:
Br J Pharmacol
Ano de publicação:
2018
Tipo de documento:
Article