Igniting Endogenous Calcipoptosis via ER-Mitochondrial Calcium Shuttle Hijacking for Potent Antitumor Immunity

Area of Science:

• Biomedical Engineering
• Cancer Immunology
• Cellular Biology

Background:

• Intracellular calcium ion (Ca²⁺) homeostasis is crucial for cell survival and immune regulation.
• Precisely controlling Ca²⁺ for antitumor immunotherapy is challenging.
• Existing strategies often rely on exogenous calcium, posing safety concerns.

Purpose of the Study:

• To develop a novel strategy for manipulating intracellular Ca²⁺ dynamics to enhance antitumor immunity.
• To engineer a nanoagonist capable of inducing calcipoptosis-mediated immune responses.
• To overcome limitations of conventional calcium-dependent immunotherapies.

Main Methods:

• Designed a modular peptide-programmed nanoagonist.
• Activated endogenous Ca²⁺ influx between organelles via endoplasmic reticulum stress and mitochondrial channel opening.
• Utilized ultrasound irradiation to trigger the nanoagonist's action.
• Assessed immune responses, including dendritic cell maturation and T-cell infiltration.

Main Results:

• The nanoagonist induced targeted organelle dysfunction, activating caspase-dependent apoptosis.
• This process released damage-associated molecular patterns, promoting anti-tumor immunity.
• Ca²⁺ dysregulation polarized macrophages and increased cancer cell stiffness, enhancing immunosurveillance.
• Demonstrated potent tumor ablation and suppressed metastasis in breast and liver cancer models.

Conclusions:

• This organelle crosstalk paradigm harnesses innate Ca²⁺ dynamics for calcipoptosis-mediated antitumor immunity.
• The nanoagonist enables customizable subcellular bioenergetic disruption with minimal systemic toxicity.
• Pioneers a translatable, calcium-based immunotherapy strategy for cancer treatment.