Positively Charged Combinatory Drug Delivery Systems against Multi-Drug-Resistant Breast Cancer: Beyond the Drug...

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Oncology

Background:

• Cancer treatment often faces challenges like drug resistance, relapse, and metastasis due to complex, multi-pathway involvement.
• Monotherapy can be insufficient against multi-drug-resistant (MDR) cancers, necessitating combination strategies targeting multiple pathways simultaneously.
• Angiogenesis and multiple signaling pathways are critical in cancer formation and progression.

Purpose of the Study:

• To develop and evaluate a combinatory drug delivery system for treating multi-drug-resistant (MDR) cancer.
• To investigate the synergistic effects of SN38, KLAK peptide, and survivin siRNA in a reductive-responsive system.
• To assess the in vitro and in vivo anticancer efficacy, including tumor accumulation, penetration, and vasculature targeting.

Main Methods:

• Preparation of combinatory drug delivery systems with high drug loading capacity, incorporating SN38, KLAK peptide, and survivin siRNA.
• Evaluation of in vitro cytotoxicity and pro-apoptotic ability against doxorubicin-resistant breast cancer cells (MCF-7/ADR).
• Assessment of in vivo anticancer efficacy, focusing on tumor accumulation, penetration, and vasculature targeting.

Main Results:

• The combinatory systems efficiently inhibited the growth of doxorubicin-resistant breast cancer cells (MCF-7/ADR) through synergistic effects and positive charge.
• Systems without siRNA demonstrated superior in vivo anticancer efficacy compared to those with siRNA.
• The enhanced in vivo efficacy was attributed to preferential tumor accumulation, strong tumor penetration, and excellent tumor vasculature targeting of SN38 and KLAK micelles.

Conclusions:

• A positively charged combinatory multitarget therapeutic system was established, capable of inducing tumor accumulation and vasculature targeting for simultaneous inhibition of tumor cells and vasculature.
• The design of combinatory drug delivery systems requires consideration of factors beyond simple drug combination, including tumor accumulation, penetration, and vascular targeting.
• This work provides insights into developing effective combination therapies for challenging cancers like MDR breast cancer.