Targeting HIF as a Promising Approach to Synergize With Immune Checkpoint Inhibitors.

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• Hypoxia-inducible factor (HIF) is upregulated in solid tumors, driving tumor cell adaptation and immune suppression.
• HIF signaling promotes tumor growth via metabolic reprogramming, angiogenesis, and malignant progression (EMT, CSCs, ECM remodeling).
• HIF in immune cells creates an immunosuppressive tumor microenvironment (TME), hindering immune surveillance and reducing therapeutic efficacy.

Purpose of the Study:

• To elucidate the multifaceted roles of HIF signaling in solid tumors and the tumor microenvironment.
• To explore the potential of HIF inhibitors as a strategy to overcome resistance to immune checkpoint inhibitors (ICIs).
• To highlight the therapeutic potential of HIF inhibition in enhancing immunotherapy for hypoxic solid tumors.

Main Methods:

• Review of preclinical and clinical studies on HIF signaling and HIF inhibitors in solid tumors.
• Analysis of HIF's impact on tumor cell biology and immune cell function within the TME.
• Evaluation of HIF inhibitors' efficacy, particularly in combination with ICIs.

Main Results:

• HIF signaling is a key driver of tumor progression and immune evasion, contributing to ICI resistance.
• HIF inhibitors have demonstrated antitumor effects in preclinical studies, with some progressing to clinical trials.
• A subset of HIF inhibitors shows synergistic effects with ICIs, suggesting potential for combination therapies.

Conclusions:

• HIF signaling is a critical target for overcoming ICI resistance in hypoxic solid tumors.
• HIF inhibitors represent a promising therapeutic strategy to reshape the TME and enhance immunotherapy.
• Targeting HIF offers a novel approach to improve treatment outcomes for patients with solid tumors.