Integrin alpha-2 and beta-1 expression increases through multiple generations of the EDW01 patient-derived xenograft model of breast cancer—insight into their role in epithelial mesenchymal transition in vivo gained from an in vitro model system

Loading...
Thumbnail Image
File version

Version of Record (VoR)

Author(s)
Wafai, R
Williams, ED
de Souza, E
Simpson, PT
McCart Reed, AE
Kutasovic, JR
Waltham, M
Snell, CE
Blick, T
Thompson, EW
Hugo, HJ
Griffith University Author(s)
Primary Supervisor
Other Supervisors
Editor(s)
Date
2020
Size
File type(s)
Location
Abstract

Background: Breast cancers acquire aggressive capabilities via epithelial to mesenchymal transition (EMT), in which various integrins/integrin-linked kinase signalling are upregulated. Methods: We investigated this in two patient-derived xenografts (PDXs) developed from breast-to-bone metastases, and its functional significance in a breast cancer cell line system. ED03 and EDW01 PDXs were grown subcutaneously in immunocompromised SCID mice through 11 passages and 7 passages, respectively. Tumour tissue was assessed using immunohistochemistry (IHC) for oestrogen receptor (ER)-alpha, E-cadherin, vimentin, Twist1, beta-catenin, P120-RasGAP, CD44, CD24 and Ki67, and RT-qPCR of EMT-related factors (CDH1, VIM, CD44, CD24), integrins beta 1 (ITGB1), alpha 2 (ITGA2) and ILK. Integrin and ILK expression in epidermal growth factor (EGF)-induced EMT of the PMC42-ET breast cancer cell line was assessed by RT-qPCR and Western blotting, as were the effects of their transient knockdown via small interfering RNA +/− EGF. Cell migration, changes in cell morphology and adhesion of siRNA-transfected PMC42-ET cells to various extracellular matrix (ECM) substrates was assessed. Results: The ED03 (ER+/PR−/HER2−/lobular) and EDW01 (ER+/PR−/HER2−/ductal) PDXs were both classified as molecular subtype luminal A. ED03 xenografts exhibited mutated E-cadherin with minimal expression, but remained vimentin-negative across all passages. In EDW01, the hypoxic indicator gene CAIX and Twist1 were co-ordinately upregulated at passages 4–5, corresponding with a decrease in E-cadherin. At passages 6–7, VIM was upregulated along with ITGB1 and ITGA2, consistent with an increasing EMT. The ED03 PDX displayed minimal change over passages in mice, for all genes examined. ILK, ITGB1 and ITGA2 mRNAs were also increased in the EGF-induced EMT of PMC42-ET cells (in which CDH1 was downregulated) although siRNA against these targets revealed that this induction was not necessary for the observed EMT. However, their knockdown significantly reduced EMT-associated adhesion and Transwell migration. Conclusion: Our data suggest that despite an increase in ITGA2 and ITGB1 gene expression in the EMT exhibited by EDW01 PDX over multiple generations, this pathway may not necessarily drive the EMT process.

Journal Title

Breast Cancer Research

Conference Title
Book Title
Edition
Volume

22

Issue

1

Thesis Type
Degree Program
School
Publisher link
Patent number
Funder(s)
Grant identifier(s)
Rights Statement
Rights Statement

© The Author(s). 2020 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 licence, and indicate if changes were made.

Item Access Status
Note
Access the data
Related item(s)
Subject

Biomedical and clinical sciences

Oncology and carcinogenesis

Cancer cell biology

Breast cancer

EMT

Hypoxia

Integrin

Patient-derived xenograft (PDX)

Persistent link to this record
Citation

Wafai, R; Williams, ED; de Souza, E; Simpson, PT; McCart Reed, AE; Kutasovic, JR; Waltham, M; Snell, CE; Blick, T; Thompson, EW; Hugo, HJ, Integrin alpha-2 and beta-1 expression increases through multiple generations of the EDW01 patient-derived xenograft model of breast cancer—insight into their role in epithelial mesenchymal transition in vivo gained from an in vitro model system, Breast Cancer Research, 2020, 22 (1), pp. 136

Collections