VDAC2 loss elicits tumour destruction and inflammation for cancer therapy

Area of Science:

• Immunology
• Molecular Biology
• Cancer Research

Background:

• Tumor cells frequently evade immune surveillance and therapeutic interventions, with underlying mechanisms remaining largely unknown.
• CD8+ T cell and immunotherapy resistance poses a significant challenge in cancer treatment.
• Understanding tumor immune evasion is critical for developing effective cancer therapies.

Purpose of the Study:

• To identify novel molecular targets that mediate tumor immune evasion.
• To investigate the role of metabolic factors in tumor resistance to immune attack.
• To explore VDAC2 as a potential target for enhancing anti-tumor immunity and immunotherapy.

Main Methods:

• In vivo and in vitro CRISPR-Cas9 genetic screens targeting metabolic factors.
• Genome-scale genetic interaction screens to identify interacting genes.
• Analysis of interferon-gamma (IFNγ) signaling pathways and mitochondrial damage.
• Assessment of cGAS-STING activation and type I IFN response.

Main Results:

• Voltage-dependent anion channel 2 (VDAC2) was identified as an immune signal-dependent checkpoint limiting IFNγ-mediated tumor destruction.
• Targeting VDAC2 in tumor cells enhanced IFNγ-induced cell death, cGAS-STING activation, and anti-tumor responses.
• BAK was identified as a key mediator of VDAC2 deficiency-induced effects, leading to uncontrolled BAK activation and mitochondrial damage.
• Aberrant release of mitochondrial DNA triggered cGAS-STING signaling and type I IFN response, enhancing anti-tumor immunity.

Conclusions:

• VDAC2 is a critical target for overcoming tumor immune evasion by enhancing both adaptive and innate immune responses.
• Targeting VDAC2 promotes tumor cell death and inflammation, improving the efficacy of cancer immunotherapies.
• Coordinated tumor destruction and inflammation are essential for successful cancer immunotherapy.