c-Met up-regulates the expression of PD-L1 through MAPK/NF-κBp65 pathway

Area of Science:

• Hepatocellular Carcinoma (HCC) Research
• Cancer Immunology
• Molecular Oncology

Background:

• Sorafenib resistance in hepatocellular carcinoma (HCC) is a significant clinical challenge.
• Programmed death-ligand 1 (PD-L1) is implicated in HCC immune escape and drug resistance, but its regulatory mechanism remains unclear.
• Understanding PD-L1 regulation is crucial for developing effective HCC therapies.

Purpose of the Study:

• To elucidate the regulatory mechanism controlling PD-L1 expression in HCC.
• To investigate the role of c-Met in PD-L1 regulation and HCC progression.
• To identify potential therapeutic targets for overcoming sorafenib resistance in HCC.

Main Methods:

• Comparative analysis of c-Met and PD-L1 expression in HCC cell lines (Huh-7SR).
• In vitro and in vivo studies to assess the impact of c-Met on HCC proliferation and migration.
• Investigation of the MAPK signaling pathway and NF-κBp65 transcription factor activation.
• Analysis of c-Met's interaction with the PD-L1 promoter region.

Main Results:

• Abnormal high expression of c-Met was observed in HCC cells with high PD-L1 expression.
• c-Met significantly promoted HCC proliferation and migration both in vitro and in vivo.
• c-Met activation of the MAPK signaling pathway led to downstream NF-κBp65 activation.
• Activated NF-κBp65 interacted with the PD-L1 promoter, enhancing PD-L1 transcription.

Conclusions:

• c-Met regulates PD-L1 transcription through the MAPK/NF-κBp65 pathway in HCC.
• This c-Met-mediated PD-L1 upregulation contributes to HCC progression and potentially sorafenib resistance.
• c-Met represents a promising therapeutic target for HCC treatment, particularly in overcoming drug resistance.