A self-amplified ROS-responsive chemodrug-inhibitor conjugate for multi-drug resistance tumor therapy

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cancer Therapy

Background:

• P-glycoprotein (P-gp) mediated multidrug resistance (MDR) significantly limits the efficacy of cancer chemotherapy.
• Current combination therapies struggle with incomplete drug release in the tumor microenvironment, leading to poor therapeutic outcomes.

Purpose of the Study:

• To develop a self-amplified, reactive oxygen species (ROS)-responsive co-delivery system for a chemodrug and P-gp inhibitor to overcome MDR.
• To enhance cancer treatment efficacy by improving drug release and overcoming P-gp mediated drug efflux.

Main Methods:

• Conjugation of tamoxifen (TAM) with D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) via an ROS-responsive aryl boronic ester bond.
• Self-assembly of TPGS-TAM conjugates into uniform spherical nanoparticles (NPs) for co-delivery.
• In vitro and in vivo assessments of the TPGS-TAM NPs in an MCF-7/ADR tumor model.

Main Results:

• The TPGS-TAM NPs demonstrated self-amplified ROS-responsive drug release, with released α-tocopherol succinate (α-TOS) further generating ROS and impairing ATP-dependent P-gp efflux.
• The developed system achieved a high tumor inhibition rate (TIR) of 74.6 ± 6.1% in the MCF-7/ADR tumor model.
• Systematic in vitro and in vivo evaluations confirmed the enhanced antitumor efficacy.

Conclusions:

• The self-amplified ROS-responsive TPGS-TAM conjugate system offers a promising carrier-free approach for co-delivery of chemodrugs and P-gp inhibitors.
• This strategy effectively reverses MDR and enhances antitumor effects, showing potential for clinical application in MDR cancer therapy.