Related Experiment Video
Updated: Feb 6, 2026
Studying the Stoichiometry of Epidermal Growth Factor Receptor in Intact Cells using Correlative Microscopy
Published on: September 11, 2015
Acid Degradable Cationic Galactose-Based Hyperbranched Polymers as Nanotherapeutic Vehicles for Epidermal Growth
Yi-Yang Peng1, Diana Diaz-Dussan2, Piyush Kumar2
1Department of Chemical and Materials Engineering , University of Alberta , Edmonton T6G 1H9 , Alberta , Canada.
Abstract:
Strong signaling cascades derived from upregulation and overexpression of growth factors such as the EGF-family (epidermal growth factors) have been crucially related to cancer pathogenesis. Gene silencing techniques to modulate the expression of oncogenes and tumor suppresor genes are a strategy that shows great promise for cancer management but still faces some limitations in the design of biocompatible and effective vectors. In this study, we synthesized, by reversible addition-fragmentation chain transfer (RAFT) polymerization, several acid degradable galactose-based hyperbranched cationic polymers with varying molecular weights (10 to 20 kDa) and compositions with 2-lactobioamidoethyl methacrylamide [LAEMA] and 2-aminoethyl methacrylamide hydrochloride [AEMA] at different ratios (2.0, 1.0, and 0.5). These polymers were then evaluated for their ability to enhance Epidermal Growth Factor Receptor (EGFR) knockdown in cervical carcinoma. All the polymer constructs have enhanced capabilities to condensate siRNA (small interfering RNA), showing low toxicity at higher LAEMA:AEMA ratios (1.0 and 2.0). Western blot assays were conducted to quantify the EGFR expression of each treatment group demonstrating superior gene knockdown efficiency for the polymers having a LAEMA:AEMA ratio of 2.0 than the lower ratio counterparts; while maintaining low toxicity levels. Gene silencing of EGFR of up to 60% was achieved with acid degradable polymers having 10 kDa molecular weight and a LAEMA:AEMA ratio of 2.0. The superior stability of the polyplexes under physiological conditions and the low cytotoxicity observed in the 48 h post-transfection demonstrated the high potential of these acid degradable galactose-based hyperbranched cationic polymers for EGFR silencing treatment applications at the clinical level.
Insights
New galactose-based polymers effectively silence the epidermal growth factor receptor (EGFR) in cervical cancer cells. These acid-degradable materials show low toxicity and high gene knockdown efficiency, offering promise for clinical cancer treatment.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Cancer Research
Background:
- Overexpression of growth factors like EGF is linked to cancer development.
- Gene silencing offers a promising cancer management strategy but requires effective delivery vectors.
- Current vectors face limitations in biocompatibility and efficacy for gene silencing applications.
Purpose of the Study:
- To synthesize and evaluate novel acid-degradable, galactose-based hyperbranched cationic polymers.
- To assess the polymers' efficacy in enhancing Epidermal Growth Factor Receptor (EGFR) gene silencing in cervical carcinoma.
- To determine the optimal polymer composition and molecular weight for efficient and safe siRNA delivery.
Main Methods:
- Synthesis of galactose-based hyperbranched cationic polymers via RAFT polymerization with varying LAEMA:AEMA ratios and molecular weights.
- Evaluation of siRNA condensation capabilities and cytotoxicity of the synthesized polymer constructs.
- Quantification of EGFR gene knockdown efficiency using Western blot assays in cervical carcinoma cells.
Main Results:
- All synthesized polymers effectively condensed siRNA, with higher LAEMA:AEMA ratios (1.0 and 2.0) exhibiting lower toxicity.
- Polymers with a LAEMA:AEMA ratio of 2.0 demonstrated superior EGFR gene knockdown efficiency compared to lower ratios.
- Up to 60% EGFR gene silencing was achieved using 10 kDa polymers with a 2.0 LAEMA:AEMA ratio, showing stability and low cytotoxicity.
Conclusions:
- Acid-degradable galactose-based hyperbranched cationic polymers are effective for EGFR gene silencing.
- The developed polymers exhibit low cytotoxicity and enhanced stability, crucial for therapeutic applications.
- These polymers hold significant potential for clinical translation in EGFR-targeted cancer therapy.
More Related Videos
Related Concept Videos
02:54Ions as Acids and Bases
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
02:34Polymers
02:33Lewis Acids and Bases
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...
00:57Cationic Chain-Growth Polymerization: Mechanism
03:26Acids, Bases and Neutralization Reactions
01:20Types of Step-Growth Polymers: Polyesters
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...