Monoclonal antibody 4C5 prevents activation of MMP2 and MMP9 by disrupting their interaction with extracellular HSP90 and inhibits formation of metastatic breast cancer cell deposits

Dimitris Stellas,Avraam El Hamidieh,Evangelia Patsavoudi

doi:10.1186/1471-2121-11-51

Dimitris Stellas, Avraam El Hamidieh + Show 1 more

Open Access

https://doi.org/10.1186/1471-2121-11-51

Copy DOI

Abstract

BackgroundHeat shock protein 90 (HSP90) is a molecular chaperone that is considered a new target for the treatment of cancer. Increasing data reveal an extracellular chaperoning activity for HSP90. Here we investigate the interaction of the secreted isoforms of HSP90 with matrix metalloproteinases (MMP) MMP2 and MMP9. Moreover we examine the role of a monoclonal antibody (mAb) against HSP90, mAb 4C5, regarding these interactions and its value as a potential inhibitor of human breast cancer cell invasion and metastasis.ResultsOur results showed that both HSP90α and HSP90β are secreted by MDAMB453 human breast cancer cells and interact with MMP2 and MMP9. MAb 4C5, while not affecting the secretion of inactive MMPs, inhibits their activation by disrupting their interaction extracellularly with both isoforms of HSP90. The in vivo studies revealed that mAb 4C5 significantly inhibits the metastatic deposit formation of MDAMB453 cells into the lungs of SCID mice.ConclusionBoth isoforms of HSP90 are secreted by MDAMB453 cells and interact with MMP2 and MMP9. MAb 4C5 prevents MMP2 and MMP9 activation, by disrupting their interaction with HSP90. Finally mAb 4C5 significantly inhibits the metastatic deposit formation of MDAMB453 cells, by preventing their extravasation and infiltration in the lung tissue and therefore it could be used as a potential therapeutic agent for cancer metastasis.

Highlights

Heat shock protein 90 (HSP90) is a molecular chaperone that is considered a new target for the treatment of cancer
After taking into account our previously mentioned recent data showing that monoclonal antibody (mAb) 4C5 inhibits MDAMB453 human breast cancer cell invasion in vitro by disrupting the association of cell surface HSP90 with HER-2,[14] in this work we examined: a) the effect of mAb 4C5 on MMP2 and MMP9 secretion and activation b) the ability of this antibody to disrupt the interaction of extracellular HSP90 with MMP2 and/or MMP9 and c) the capacity of mAb 4C5 to inhibit in vivo, the formation of metastatic deposits of MDAMB453 cells in the lungs of SCID mice. Both the a and b isoforms of HSP90 are secreted by MDAMB453 breast cancer cells and interact with MMP2 and MMP9 In order to investigate the secretion of the a and b isoforms of HSP90 by MDAMB453 cells, cell lysates and concentrated supernatants derived from the culture of these cells were analyzed by Western blotting using mAb 4C5 which recognizes both isoforms of HSP90[16], and the commercially available anti-HSP90 a and anti-HSP90 b antibodies
After confirming the presence of both proMMP2 and pro-MMP9 as well as their activated forms in the culture medium of MDAMB453 cells (Figure.1B), we showed by immunoprecipitation experiments in the culture supernatant using anti-MMP2 and anti-MMP9 antibodies followed by Western blot analysis with antibodies against the a and b isoforms of HSP90, that both isoforms of HSP90 interact with the metalloproteinases examined (Figure.1B)

Summary

Introduction

Heat shock protein 90 (HSP90) is a molecular chaperone that is considered a new target for the treatment of cancer. The heat shock protein 90 (HSP90) is a molecular chaperone which exists in mammalian cells in two isoforms that share 86% aminoacid conservation (HSP90a and HSP90b). It is one of the most abundant cytoplasmic proteins in unstressed cells, where it performs housekeeping functions, controlling the activity, intracellular disposition and proteolytic turnover of a variety of proteins. We have presented data indicating that surface HSP90 interacts with the extracellular domain of HER-2 and that this interaction which is necessary for the receptor’s activation leading to breast cancer cell invasion, is disrupted by mAb 4C5 [14]

Methods

Results

Discussion

Conclusion