Non-Covalently Stapled H⁺ /Cl^- Ion Channels Activatable by Visible Light for Targeted Anticancer Therapy

Area of Science:

• Biomedical Engineering
• Materials Science
• Cancer Therapy

Background:

• Cancer therapy requires selective targeting to minimize side effects.
• Artificial ion channels offer potential for precise control of cellular processes.
• Stimuli-responsive materials enable targeted drug delivery and therapy activation.

Purpose of the Study:

• To develop novel stimuli-responsive artificial ion channels for selective cancer therapy.
• To investigate the mechanism of action and efficacy of these channels in cancer cells.
• To assess the safety profile of the artificial channels in normal cells.

Main Methods:

• Synthesis and characterization of non-covalently stapled self-assembled artificial channels (C4F-L).
• Activation of channels using biocompatible visible light (442 nm).
• Assessment of H+/Cl- ion transport efficiency and selectivity.
• Evaluation of cytotoxicity against human colorectal cancer cells and normal intestine cells.
• Investigation of cancer cell death pathways, including apoptosis and autophagy.

Main Results:

• Developed artificial channels activated by visible light with H+/Cl- transport selectivity of 6.0.
• Photoirradiation restored 90% ion transport efficiency within 10 minutes.
• Achieved a 10.5-fold enhancement in cytotoxicity against colorectal cancer cells (IC50 = 8.5 μM).
• Demonstrated minimal toxicity towards normal intestine cells at high concentrations (200 μM).
• Identified cancer cell death mechanisms involving caspase-9 apoptosis and autophagy disruption.

Conclusions:

• Light-activatable artificial ion channels represent a promising strategy for selective cancer therapy.
• These channels effectively induce cancer cell death via apoptosis and autophagy disruption.
• The developed system exhibits high selectivity and a favorable safety profile, sparing normal cells.