Multivalent exposure of trastuzumab on iron oxide nanoparticles improves antitumor potential and reduces resistance in HER2-positive breast cancer cells

Abstract

Targeted therapies have profoundly changed the clinical prospect in human epidermal growth factor receptor 2 (HER2)-positive breast cancer. In particular, the anti-HER2 monoclonal antibody trastuzumab represents the gold standard for the treatment of HER2+ breast cancer patients. Its contribution in dampening cancer progression is mainly attributed to the antibody-dependent cell-mediated cytotoxicity (ADCC) rather than HER2 blockade. Here, multiple half chains of trastuzumab were conjugated onto magnetic iron oxide nanoparticles (MNP-HC) to develop target-specific and biologically active nanosystems to enhance anti-HER2 therapeutic potential. HER2 targeting was assessed in different human breast cancer cell lines, where nanoparticles triggered site-specific phosphorylation in the catalytic domain of the receptor and cellular uptake by endocytosis. MNP-HC induced remarkable antiproliferative effect in HER2+ breast cancer cells, exhibiting enhanced activity compared to free drug. Accordingly, nanoparticles induced p27kip1 expression and cell cycle arrest in G1 phase, without loosing capability to prime ADCC. Finally, MNP-HC affected viability of trastuzumab-resistant cells, suggesting interference with the resistance machinery. Our findings indicate that multiple arrangement of trastuzumab half chain on the nanoparticle surface enhances anticancer efficacy in HER2+ breast cancer cells. Powerful inhibition of HER2 signaling could promote responsiveness of resistant cells, thus suggesting ways for drug sensitization.

Tailoring Iron Oxide Nanoparticles for Efficient Cellular Internalization and Endosomal Escape

“…In the case of VEGFR targeting, the preferred antibodies include bevacizumab [ 193 ] and anti-VEGF monoclonal antibodies [ 194 ]. The human epidermal receptor 2 (HER-2), a member of the EGFR family, has also been targeted with ION modified with a number of antibodies, including trastuzumab [ 195 ] and the anti-HER2 affibody [ 196 ]. Although HER-2 has no natural ligands and is rarely endocytosed, HER-2 antibody binding induces post-translational modifications that mediate its internalization through CME [ 197 ].…”

Dual pH- and GSH-Responsive Degradable PEGylated Graphene Quantum Dot-Based Nanoparticles for Enhanced HER2-Positive Breast Cancer Therapy

“…The selective targeting properties of anticancer drug carriers are key in enhancing their anticancer efficacies and reducing side effects. The significant difference in HER2 levels between HER2-negative and HER2-positive breast cancer enables HER-containing drug carriers to access HER2-positive breast cancer [44][45][46]. Prior to in vitro studies, validation of HER2 expression in the SK-BR-3 and MDA-MB-231 cell lines was conducted with SDS-PAGE and immunoblot analysis.…”

<p>Anti-MAdCAM-1-Conjugated Nanocarriers Delivering Quantum Dots Enable Specific Imaging of Inflammatory Bowel Disease</p>

“…The antibody binding was performed according to a previous protocol. 31 Briefly, in order to reduce the disulfide bridges between the two heavy chains of the antibody, anti-MAdCAM1 or trastuzumab (TZ, Herceptin, Genentech) were dissolved in EDTA–PBS (10 µg/mL) and added to the 2-mercaptoethanolamine kit (MEA, Thermo Fisher Scientific). The obtained half-chain antibody portions (HC) were immediately added to NPs (1 mg) and incubated for 3 h at 4°C.…”

“…At the end of incubation, cells were washed three times with PBS, detached and collected in eppendorf tubes for examination by TEM (Tecnai Spirit BioTWIN), as previously described. 31 …”

“…Cells were washed three times with PBS, stained with Alexa Fluor-488-conjugated secondary antibody and analyzed by CytoFLEX flow cytometer (Beckman Coulter), as previously reported. 31 …”