Engineering Hypoxia-Lactate-Ca Coupling for Metabolic-Ion Intervention in Cancer Immunotherapy

Area of Science:

• Biomedical Engineering
• Cancer Research
• Immunology

Background:

• Tumor microenvironments (TMEs) are often hypoxic and rich in lactate, creating metabolic immunosuppression that hinders cancer immunotherapy.
• Blocking lactate export alone is insufficient due to continuous lactate production and can lead to intracellular stress.

Purpose of the Study:

• To develop a TME-activated nanoreactor (CZCH) that exploits lactate trapping to enhance cancer immunotherapy.
• To investigate the mechanism of Ca2+-mediated immunogenic stress amplification for tumor immunomodulation.

Main Methods:

• Designed a TME-activated nanoreactor (CZCH) that alleviates hypoxia, blocks lactate efflux, and releases Ca2+ within tumor cells.
• Investigated the synergistic effects of intracellular lactate trapping and Ca2+ release on mitochondrial dysfunction and immunogenic cell death.
• Assessed the impact of CZCH on immune cell populations (dendritic cells, macrophages) and tumor growth in vivo.

Main Results:

• CZCH effectively traps intracellular lactate and amplifies Ca2+-mediated stress, leading to mitochondrial dysfunction and immunogenic cell death.
• CZCH reshapes the immunosuppressive TME by promoting dendritic cell maturation and M1-like macrophage repolarization.
• In vivo studies showed CZCH suppressed primary tumor growth, reduced metastasis, and improved response to αPD-L1 blockade.

Conclusions:

• Lactate trapping combined with Ca2+ sensitization is a viable therapeutic strategy for cancer immunotherapy.
• CZCH offers a novel nanomaterial approach for metabolic-ionic intervention to overcome immunotherapy resistance.