Development of High-Loading Trastuzumab PLGA Nanoparticles: A Powerful Tool Against HER2 Positive Breast Cancer Cells

Abstract

Tania Mariastella Caputo,1,* Giovannina Barisciano,2,* Chiara Mulè,1 Angela Maria Cusano,3 Anna Aliberti,1 Livio Muccillo,2 Vittorio Colantuoni,2 Lina Sabatino,2 Andrea Cusano1,3 1Optoelectronics Group, Department of Engineering, University of Sannio, Benevento, Italy; 2Department of Sciences and Technologies, University of Sannio, Benevento, Italy; 3CeRICTscrl Regional Center Information Communication Technology, Benevento, Italy*These authors contributed equally to this workCorrespondence: Anna Aliberti; Lina Sabatino, Email [email protected]; [email protected]: Trastuzumab, a therapeutic monoclonal antibody directed against HER2, is routinely used to treat HER2-positive breast cancer with a good response rate. However, concerns have arisen in the clinical practice due to adverse side effects. One way to overcome these limitations is to encapsulate trastuzumab in nanoparticles to improve cytotoxic activity, increase intracellular drug concentrations, escape the immune system and avoid systemic degradation of the drug in vivo.Methods: A double emulsion method was used to encapsulate trastuzumab into poly(lactic-co-glycolic) nanoparticles, effective for their biocompatibility and biodegradability. These nanocarriers, hereafter referred to as TZPs, were characterised in terms of size, homogeneity, zeta potential and tested for their stability and drug release kinetics. Finally, the TZPs cytotoxicity was assessed in vitro on the HER2 positive SKBR3 breast cancer cell line and compared to free trastuzumab.Results: The TZPs were stable, homogeneous in size, with a reduced zeta potential. They showed higher encapsulation efficiency and drug loading, a prolonged trastuzumab release kinetics that retained its physicochemical properties and functionality. TZPs showed a stronger cytotoxicity and increased apoptosis than similar doses of free trastuzumab in the cell line analysed. Confocal microscopy and flow cytometry assessed TZPs and trastuzumab cellular uptake while Western blot evaluated downstream signalling, overall HER2 content and shedding.Conclusion: TZPs exert more robust effects than free trastuzumab via a dual mode of action: TZPs are taken up by cells through an endocytosis mechanism and release the drug intracellularly for longer time. Additionally, the TZPs that remain in the extracellular space release trastuzumab which binds to the cognate receptor and impairs downstream signalling. This is the sole modality used by free trastuzumab. Remarkably, half dose of TZPs is as efficacious as the highest dose of free drug supporting their possible use for drug delivery in vivo. Keywords: PLGA nanoparticles, double-emulsion method, trastuzumab, breast cancer, signaling transduction

Keywords

• plga nanoparticles
• double-emulsion method
• trastuzumab
• breast cancer
• signaling transduction.