# Single-Cell Transcriptomic Profiling Reveals That Macrophage-Induced Angiogenesis Contributes to Immunotherapy Resistance in Hepatocellular Carcinoma

## TL;DR

This study finds that a specific type of macrophage contributes to immunotherapy resistance in liver cancer by promoting blood vessel growth and immune suppression.

## Contribution

Identifies NFKBIZ+ M0 macrophages as a novel driver of anti-PD-1 resistance in hepatocellular carcinoma.

## Key findings

- NFKBIZ+ M0 macrophages are enriched in patients non-responsive to anti-PD-1 treatment.
- These macrophages promote angiogenesis and immune evasion through VEGFA, HBEGF, and inflammatory chemokines.
- FOSB–VEGFA and FOS–HBEGF signaling pathways drive the harmful macrophage behavior.

## Abstract

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide, and many patients do not respond well to immunotherapy. In this study, we identified a unique group of macrophages—called NFKBIZ+ M0 macrophages—that are enriched in patients non-responsive to anti-PD-1 treatment. These macrophages are activated by hypoxia and release factors such as VEGFA and HBEGF that promote new blood vessel formation and tumor growth. They also produce inflammatory molecules that suppress the immune system, helping the tumor evade immune attack. Further analysis revealed that specific signaling pathways (FOSB–VEGFA and FOS–HBEGF) drive this harmful macrophage behavior. Our findings uncover a new mechanism linking hypoxia, angiogenesis, and immune evasion to treatment resistance in HCC and suggest potential therapeutic targets to improve immunotherapy outcomes.

Hepatocellular carcinoma (HCC) ranks among the top causes of cancer-related mortality worldwide, and its complex tumor microenvironment (TME) contributes to poor responses to immunotherapy. Although PD-1/PD-L1 blockade has emerged as an effective treatment strategy, therapeutic resistance frequently limits its clinical benefit. Here, we uncover a distinct macrophage population associated with anti-PD-1 resistance in HCC. Single-cell transcriptomic profiling reveals an NFKBIZ+ M0 macrophage subset predominantly present in non-responders. Notably, these macrophages exhibit a hypoxia-induced phenotype characterized by the secretion of VEGFA and HBEGF, which cooperatively enhance tumor angiogenesis, alongside an elevated expression of the inflammatory chemokines CXCL2, CXCL3, and CXCL8 that consolidate an immunosuppressive, pro-tumorigenic microenvironment. Transcriptional regulatory network analysis further identified FOSB–VEGFA and FOS–HBEGF axes as key drivers of this pathogenic macrophage phenotype. Our findings define a distinct NFKBIZ+ macrophage population that mechanistically links hypoxia, angiogenesis, and immune evasion to PD-1 blockade resistance. This work provides new insights into the cellular and molecular basis of immunotherapy failure in HCC and highlights potential targets for overcoming treatment resistance.