Mitochondrial transfer in the HSC–HCC–macrophage network shapes hepatocellular carcinoma progression

La Zhang, Cong Ren, Miao He, Xinyu Chen, Hongqing Liu, Yilin Liu, Jing Luo, Zhenghang Li,

Jianwei Wang, Wenjun Miao, Qiling Peng, and Ning Jiang

PNAS; February 5, 2026; 123 (6) e2512592123; https://doi.org/10.1073/pnas.2512592123

Significance

Hepatocellular carcinoma (HCC) cells employ a dual parasitic strategy: acquiring functional mitochondria from hepatic stellate cells via tunneling nanotubes (TNTs) to sustain growth and offloading damaged mitochondria to macrophages through extracellular vesicles (EVs) for survival. Disrupting this mitochondrial transfer into and out of cancer cells represents a promising therapeutic avenue. The responsive liposomal nanocarrier L&G@Lipo^PPV emerges as an effective intervention, targeting both TNT- and EV-mediated pathways to inhibit tumorigenesis, offering a targeted approach to combat HCC’s adaptive mitochondrial hijacking and evasion mechanisms.

Abstract

Mitochondrial crosstalk between tumor cells and components of the tumor microenvironment (TME) is a critical yet underexplored mechanism driving hepatocellular carcinoma (HCC) progression. Here, we demonstrate that in HCC, mitochondria can be transferred from hepatic stellate cells to cancer cells via tunneling nanotubes (TNTs), supplying essential energy for tumor growth. Simultaneously, cancer cells offload damaged mitochondria to macrophages through extracellular vesicles (EVs), facilitating their clearance and promoting tumor development. To disrupt this mitochondrial exchange, we developed a responsive liposomal nanocarrier (L&G@Lipo^PPV) coencapsulating L-778123 and GW4869 to simultaneously inhibit TNT-mediated and vesicle-mediated mitochondrial transfer. This work provides the first comprehensive evidence of mitochondrial transfer dynamics in the TME, with tumor cells as the central hub, and highlights L&G@Lipo^PPV as an innovative and effective strategy to block mitochondrial crosstalk. Our findings address critical challenges of drug solubility and delivery, offering a rational approach to reprogram the TME and suppress liver cancer progression.

See https://www.pnas.org/doi/10.1073/pnas.2512592123

Fig. 1. HSCs as the dominant contributors to mitochondrial transfer in HCC. (A) UMAP plot visualizing cellular populations in the HCC microenvironment. (B) Distribution of cell types in tumor and each tumor sample. (C) Schematic of experimental design for mitochondrial labeling and coculturation. HSCs, ECs, macrophages, and T cells were defined as the donor cell separately, labeled with mitoTracker and cocultured with HCC cells (Huh7 cells or MHCC-97H cells) marked with CellTrace green for different time intervals. (D–G) Confocal imaging of mitochondrial transfer dynamics from HSCs, ECs, macrophages, and T cells to Huh7 cells over 0, 8, 16, and 24 h after cell attachment. The mitochondria (red) in donor cells were labeled with mitoTracker before coculturing with Huh7 cells (green), rhodamine phalloidin (turquoise) labeling cellular actin and white dashed boxes represent Huh7 cells. (Scale bar: 20 μm). (H) Quantification of mean fluorescent intensity of mitochondria from donor cells in Huh7 cells of (D–G) (n = 6). (I–L) Flow cytometry analysis showing fluorescence intensity of transferred mitochondria in recipient HCC cells. (M–P) Confocal microscopy images showing mitochondrial transfer from HSCs, ECs, macrophages, and T cells to MHCC-97H cells at 0, 8, 16, and 24 h post-co-culture. Mitochondria in donor cells (red), MHCC-97H cells (green), actin filaments (turquoise), and white dashed boxes represent MHCC-97H cells. (Scale bar: 20 μm.) (U) Quantification of mean fluorescence intensity of mitochondria from donor cells transferred to MHCC97H cells as shown in (M-P) (n = 6). (Q-T) Flow cytometry analysis illustrating the fluorescence intensity of mitochondria transferred to MHCC-97H cells.