pH-Responsive Supramolecular System for Activation of Cellular Calcium Channels

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Precise activation of ion channels within the tumor microenvironment (TME) is crucial for cellular signaling but remains a significant challenge.
• Existing methods lack on-demand control and specificity in targeting tumor-specific conditions.

Purpose of the Study:

• To engineer a pH-responsive supramolecular assembly for targeted ion channel activation in the TME.
• To investigate the potential of this system in modulating calcium influx and enhancing antitumor immune responses.

Main Methods:

• Development of a pH-responsive supramolecular assembly using a cationic oligophenylenevinylene derivative (OPV-hex) and an acid-cleavable molecule (DMMA).
• Assessment of the assembly's disassembly and release of OPV-hex in acidic, tumor-mimicking conditions.
• Electrophysiological experiments and inhibitor studies to confirm ion channel activation (TRPV1, voltage-gated Ca2+ channels) and calcium influx (Ca2+).
• Transcriptomic analysis to evaluate pathway enrichment (apoptosis, calcium signaling) and macrophage polarization.

Main Results:

• The supramolecular assembly effectively shields OPV-hex at physiological pH and releases it in acidic TME conditions.
• Released OPV-hex targets the plasma membrane, activating calcium ion channels and leading to significant Ca2+ influx in tumor cells and macrophages.
• Confirmation of TRPV1 and voltage-gated Ca2+ channel involvement in the observed calcium influx.
• Transcriptomic data revealed enrichment of apoptosis and calcium-related pathways, alongside potential for enhanced antitumor immunity via macrophage polarization.

Conclusions:

• A novel molecular conformation-driven strategy for pH-triggered ion channel modulation was successfully developed.
• The pH-responsive system demonstrates potential as a targeted platform for cancer therapy by modulating ion channels and immune responses.
• This approach offers a promising avenue for precise, on-demand activation of cellular signaling pathways within the tumor microenvironment.