Integrated analysis of multiple receptor tyrosine kinases identifies Axl as a therapeutic target and mediator of resistance to sorafenib in hepatocellular carcinoma.
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Background: Aberrant activation of Axl is implicated in the progression of HCC. We explored biologic significance and preclinical efficacy of Axl inhibition as a therapeutic strategy in sorafenib-naïve and resistant HCC.
Methods: We evaluated Axl expression in sorafenib-naïve and resistant (SR) clones of epithelial (HuH7) and mesenchymal origin (SKHep-1) using antibody arrays and confirmed tissue expression. We tested the effect of Axl inhibition with RNA-interference and pharmacologically with R428 on a number of phenotypic assays.
Results: Axl mRNA overexpression in cell lines (n=28) and RNA-seq tissue datasets (n=373) correlated with epithelial-to-mesenchymal transition (EMT). Axl was overexpressed in HCC compared to cirrhosis and normal liver. We confirmed sorafenib-resistance to be associated with EMT and enhanced motility in both HuH7-SR and SKHep-1-SR cells documenting a 4-fold increase in Axl phosphorylation as an adaptive feature of chronic sorafenib treatment in SKHep-1-SR cells. Axl inhibition reduced motility and enhanced sensitivity to sorafenib in SKHep-1SR cells. In patients treated with sorafenib (n=40) circulating Axl levels correlated with shorter survival.
Conclusions: Suppression of Axl-dependent signaling influences the transformed phenotype in HCC cells and contributes to adaptive resistance to sorafenib, providing a pre-clinical rationale for the development of Axl inhibitors as a measure to overcome sorafenib resistance.
Methods: We evaluated Axl expression in sorafenib-naïve and resistant (SR) clones of epithelial (HuH7) and mesenchymal origin (SKHep-1) using antibody arrays and confirmed tissue expression. We tested the effect of Axl inhibition with RNA-interference and pharmacologically with R428 on a number of phenotypic assays.
Results: Axl mRNA overexpression in cell lines (n=28) and RNA-seq tissue datasets (n=373) correlated with epithelial-to-mesenchymal transition (EMT). Axl was overexpressed in HCC compared to cirrhosis and normal liver. We confirmed sorafenib-resistance to be associated with EMT and enhanced motility in both HuH7-SR and SKHep-1-SR cells documenting a 4-fold increase in Axl phosphorylation as an adaptive feature of chronic sorafenib treatment in SKHep-1-SR cells. Axl inhibition reduced motility and enhanced sensitivity to sorafenib in SKHep-1SR cells. In patients treated with sorafenib (n=40) circulating Axl levels correlated with shorter survival.
Conclusions: Suppression of Axl-dependent signaling influences the transformed phenotype in HCC cells and contributes to adaptive resistance to sorafenib, providing a pre-clinical rationale for the development of Axl inhibitors as a measure to overcome sorafenib resistance.
Date Issued
2019-03-05
Date Acceptance
2018-12-14
Citation
British Journal of Cancer, 2019, 120 (5), pp.512-521
ISSN
0007-0920
Publisher
Springer Nature [academic journals on nature.com]
Start Page
512
End Page
521
Journal / Book Title
British Journal of Cancer
Volume
120
Issue
5
Copyright Statement
© The Author(s) 2019. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
Sponsor
The Academy of Medical Sciences
Grant Number
N/A
Subjects
Science & Technology
Life Sciences & Biomedicine
Oncology
SYSTEMIC THERAPIES
TUMOR PHENOTYPE
SURVIVAL
EXPRESSION
INHIBITOR
CANCER
HETEROGENEITY
PERSPECTIVES
ACTIVATION
MECHANISM
Oncology & Carcinogenesis
1112 Oncology and Carcinogenesis
Publication Status
Published
Date Publish Online
2019-02-15