# Overcoming MDSC-Mediated Immunosuppression in Hepatocellular Carcinoma: From Mechanisms to Novel Immunotherapeutic Approaches

## TL;DR

This paper reviews how myeloid-derived suppressor cells (MDSCs) hinder immune responses in liver cancer and explores new therapies to overcome this resistance.

## Contribution

The paper introduces multi-modal strategies targeting MDSCs, including metabolic modulators and microbiome interventions, combined with AI-driven precision immunotherapy.

## Key findings

- MDSCs promote immunosuppression in HCC via JAK–STAT3 and CXCL12-CXCR4 pathways.
- Therapies like STAT3 inhibitors and microbiome modulation show promise in preclinical and clinical studies.
- AI-driven multi-omics integration aids in discovering biomarkers for personalized HCC treatments.

## Abstract

Myeloid-derived suppressor cells (MDSCs) play a central role in promoting immune evasion and resistance to immune checkpoint blockade (ICB) therapies in hepatocellular carcinoma (HCC), a leading cause of cancer-related deaths worldwide. This review elucidates key mechanisms driving MDSC-mediated immunosuppression, including interconnected signaling pathways like JAK–STAT3 and CXCL12-CXCR4, metabolic reprogramming such as enhanced glycolysis and lipid metabolism, and epigenetic modifications that sustain tumor tolerance. Emerging therapeutic strategies, including STAT3 inhibitors, metabolic modulators (e.g., tadalafil and SQLE blockers), microbiome interventions via fecal microbiota transplantation or probiotics, and combinations with ICB or locoregional therapies like transarterial chemoembolization, demonstrate promising efficacy in preclinical and clinical studies by depleting MDSCs, reprogramming the tumor microenvironment, and enhancing antitumor immunity. These insights position MDSCs as pivotal targets for precision immunotherapy, with AI-driven multi-omics integration facilitating biomarker discovery and personalized regimens to improve response rates and patient outcomes in HCC.

Background: Myeloid-derived suppressor cells (MDSCs) drive immunosuppression in the hepatocellular carcinoma (HCC) tumor microenvironment (TME), contributing to immune checkpoint blockade (ICB) resistance. This review explores underlying mechanisms and therapeutic strategies. Methods: We synthesize the recent literature on MDSC biology in HCC, focusing on signaling pathways, metabolic/epigenetic reprogramming, and novel interventions, including AI-driven analyses. Results: Key mechanisms include JAK–STAT3 activation for MDSC expansion, CXCL12-CXCR4 for recruitment, enhanced glycolysis/lipid metabolism for suppressive function, and epigenetic changes sustaining immunosuppression. Therapeutic approaches encompass inhibitors, differentiation promoters, metabolic modulators, transcriptional reprogramming, microbiome modulation, and combinations with ICB/locoregional therapies or standard chemoimmunotherapy, yielding improved outcomes in trials. Conclusions: Targeting MDSC redundancies via multi-modal strategies offers a roadmap for overcoming resistance, with AI enhancing biomarker-guided precision immunotherapy in HCC.