Anticancer activity of paclitaxel-loaded keratin nanoparticles in two-dimensional and perfused three-dimensional breast cancer models

Abstract

PurposeTaxanes are highly effective cytotoxic drugs for progressing breast cancer treatment. However, their poor solubility and high toxicity urge the development of innovative formulations of potential clinical relevance.Materials and methodsBy using a simple and straightforward aggregation method, we have generated paclitaxel (PTX) loaded in keratin nanoparticles (KER-NPs-PTX). Their activities were tested against human breast cancer MCF-7 and MDA MB 231 cell lines in conventional two-dimensional (2D) cultures and in a dynamic three-dimensional (3D) model with perfused bioreactor (p3D). Moreover, KER-NPs-PTX activity was compared to free PTX and to PTX loaded in albumin nanoparticles (HSA-NPs-PTX). Cell viability, induction of apoptosis, and gene expression analysis were used as readouts.ResultsIn 2D cultures, KER-NPs-PTX was able to inhibit tumor cell viability and to induce apoptosis similarly to PTX and HSA-NPs-PTX. In the p3D model, a lower sensitivity of tumor cells to treatments was observed. Importantly, only KER-NPs-PTX was able to induce a statistically significant increase in apoptotic cell percentages following 24 h treatment for MCF-7 (16.7±4.0 early and 11.3±4.9 late apoptotic cells) and 48 h treatment for MDA MB 231 (21.3±11.2 early and 10.5±1.8 late apoptotic cells) cells. These effects were supported, at least for MCF-7 cells, by significant increases in the expression of proapoptotic BAX gene (5.8±0.5) 24 h after treatment and of cleaved caspase 3 (CC3) protein.ConclusionKER-NPs-PTX, generated by a simple procedure, is characterized by high water solubility and enhanced PTX-loading ability, as compared to HSA-NPs-PTX. Most importantly, it appears to be able to exert effective anticancer activities on breast cancer cells cultured in 2D or in p3D models.

Functionalized Keratin as Nanotechnology-Based Drug Delivery System for the Pharmacological Treatment of Osteosarcoma

“…In the aggregation method, the high affinity of PTX for keratin hydrophobic domains induces the spontaneous formation of stable nanoparticles [ 23 ], thus it does not require the use of toxic crosslinking agents and tedious purification procedures, such as ultrafiltration and dialysis. To maintain a fixed amount of Ker-Ce6, a double volume of PTX is required to provide PTX-Ce6@ker ag formation.…”

“…[ 22 ]. To overcome these limitations, several materials, both synthetic and natural, are currently being extensively investigated as valid alternatives to become drugs carriers in cancer treatment and hence to improve drugs efficacy [ 23 ]. In the present work, we focused our attention on keratin.…”

“…This natural biopolymer is a cysteine-rich structural protein, highly biocompatible and with exclusive tri-peptidic sequences present on its backbone, such as the “Arg–Gly–Asp” (RGD) and “Leu–Asp–Val” (LDV) sequences, that specifically bind vitronectin integrin receptors which are overexpressed by several cancer cells, including osteosarcoma cells [ 24 ]. Moreover, when compared to albumin, keratin displays higher drug-loading ability, yields, reproducibility, and easier scalability, due to its unique structural and chemical features [ 23 , 25 ]. All of these properties make keratin a promising material for nanoparticles-mediated drug delivery.…”

The comparative analysis of the methods for keratin extraction from sheep wool and human hair

“…This feature of keratin provides its use in various fields. In the literature there are many information about the application of keratin to develop nanofibers [18], hydrogels [13], films [11], 3D-scaffold for tissue engineering [19], nanocontainers for controlled drug delivery [6,14], wound healing [9], nerve regeneration [16], for the creation of functional nanomaterials [7].…”

The Role of Biomimetic Hypoxia on Cancer Cell Behaviour in 3D Models: A Systematic Review

“…We identified a total of 42 publications [ 16 , 19 , 22 , 23 , 30 , 41 , 42 , 45 , 49 , 52 , 56 , 59 , 61 , 64 , 68 , 72 , 74 , 80 , 85 , 89 , 100 , 101 , 102 , 103 , 105 , 106 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 ] comparing cell response to chemotherapy and other interventions between 2D and 3D in vitro tumour models, using a variety of anticancer agents and taking into account any publications which involved more than one type of anticancer agents, yielding in total 85 separate findings, including 79 outcomes concerning chemotherapy agents, three involving radiotherapy, and a further five exploring natural compound agents such as orange-peel flavones. The definitions for drug response varied throughout the studies in terms of markers used and duration over which drug responses were measured.…”