Header

UZH-Logo

Maintenance Infos

Structural basis for eliciting a cytotoxic effect in HER2-overexpressing cancer cells via binding to the extracellular domain of HER2


Jost, Christian; Schilling, Johannes; Tamaskovic, Rastislav; Schwill, Martin; Honegger, Annemarie; Plückthun, Andreas (2013). Structural basis for eliciting a cytotoxic effect in HER2-overexpressing cancer cells via binding to the extracellular domain of HER2. Structure, 21(11):1979-1991.

Abstract

Human epidermal growth factor receptor-2 (HER2) is a receptor tyrosine kinase directly linked to the growth of malignancies from various origins and a validated target for monoclonal antibodies and kinase inhibitors. Utilizing a new approach with designed ankyrin repeat proteins (DARPins) as alternative binders, we show that binding of two DARPins connected by a short linker, one targeting extracellular subdomain I and the other subdomain IV, causes much stronger cytotoxic effects on the HER2-addicted breast cancer cell line BT474, surpassing the therapeutic antibody trastuzumab. We determined crystal structures of these DARPins in complex with the respective subdomains. Detailed models of the full-length receptor, constrained by its rigid domain structures and its membrane anchoring, explain how the bispecific DARPins connect two membrane-bound HER2 molecules, distorting them such that they cannot form signaling-competent dimers with any EGFR family member, preventing any kinase dimerization, and thus leading to a complete loss of signaling.

Abstract

Human epidermal growth factor receptor-2 (HER2) is a receptor tyrosine kinase directly linked to the growth of malignancies from various origins and a validated target for monoclonal antibodies and kinase inhibitors. Utilizing a new approach with designed ankyrin repeat proteins (DARPins) as alternative binders, we show that binding of two DARPins connected by a short linker, one targeting extracellular subdomain I and the other subdomain IV, causes much stronger cytotoxic effects on the HER2-addicted breast cancer cell line BT474, surpassing the therapeutic antibody trastuzumab. We determined crystal structures of these DARPins in complex with the respective subdomains. Detailed models of the full-length receptor, constrained by its rigid domain structures and its membrane anchoring, explain how the bispecific DARPins connect two membrane-bound HER2 molecules, distorting them such that they cannot form signaling-competent dimers with any EGFR family member, preventing any kinase dimerization, and thus leading to a complete loss of signaling.

Statistics

Citations

31 citations in Web of Science®
32 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

0 downloads since deposited on 06 Feb 2014
0 downloads since 12 months

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > Department of Biochemistry
07 Faculty of Science > Department of Biochemistry
Dewey Decimal Classification:570 Life sciences; biology
Language:English
Date:2013
Deposited On:06 Feb 2014 13:43
Last Modified:05 Apr 2016 17:30
Publisher:Cell Press (Elsevier)
ISSN:0969-2126
Free access at:Publisher DOI. An embargo period may apply.
Publisher DOI:https://doi.org/10.1016/j.str.2013.08.020
PubMed ID:24095059

Download