Cancer researchers reveal that tumor cells acquire mitochondria from immune cells, dampening anti-tumor immune responses and promoting lymph node metastasis through activation of the cGAS-STING pathway and type I interferon signaling.

Human data analyses associate higher mitochondrial transfer signatures with lymph node metastasis and activation of the cGAS-STING pathway, though predictive power depends on mitochondrial coverage and cell numbers.

Transfer requires direct cell contact and is enhanced under hypoxic and inflammatory conditions; disruption of transfer structures or key transfer factors reduces mitochondrial transfer and lowers lymph node metastasis in mouse models.

mtDNA polymorphism and donor-origin tracking confirmed that immune-derived mitochondria become part of tumor cells, providing evidence of cross-cell mitochondrial transfer as a mechanism for metastasis.

Targeting either mitochondrial transfer processes or the resulting cGAS-STING signaling could be a therapeutic strategy to limit early lymph node metastasis and potentially systemic cancer progression.

The authors propose a two-pronged model: loss of donor mitochondria impairs immune surveillance, while acquired mitochondria activate cGAS-STING in tumor cells to promote immune evasion and lymph node colonization.

Immune cells that lose mitochondria exhibit reduced antigen presentation and cytotoxic functions, while tumor cells receiving immune-derived mitochondria show increased immune-evasion markers and activation of interferon signaling linked to lymph node spread.

The study is published in Cell Metabolism (2026) by Azusa Terasaki et al., with supporting data from multiple experimental approaches and acknowledgment of funding and editorial checks.

The study tracked mitochondrial transfer across colon, breast, and melanoma models using tagged cancer cells and mitochondrial reporters in mice, showing higher transfer to tumor cells in draining lymph nodes than in primary tumors.