Oleic acid and oleoylethanolamide decrease interferon-γ-induced expression of PD-L1 and induce apoptosis in human...

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Programmed death-ligand 1 (PD-L1) inhibition is a strategy to prevent cancer progression.
• Oleic acid exhibits anti-cancer properties, but its effect on PD-L1 is unproven.

Purpose of the Study:

• To investigate the effects of oleic acid and oleoylethanolamide (OEA) on PD-L1 expression and tumorigenesis biomarkers.
• To explore the potential of these compounds in cancer prevention.

Main Methods:

• Utilized RT-PCR to analyze PD-L1 and apoptosis-related gene expression in A549, HuH-7, MCF-7, DLD-1, and LoVo cancer cell lines.
• Employed western blotting to assess Interferon-gamma (IFN-γ)-induced PD-L1 protein modulation.
• Examined the impact on STAT phosphorylation.

Main Results:

• IFN-γ stimulation increased PD-L1 expression across tested cancer cell lines, notably in A549 cells.
• Oleic acid and OEA reduced IFN-γ-induced PD-L1, Bax, Bcl-2, and caspase 3 expression in A549 cells.
• Both compounds decreased IFN-γ-induced STAT phosphorylation.

Conclusions:

• Oleic acid and OEA inhibit PD-L1 expression and promote apoptosis via STAT phosphorylation.
• These findings suggest oleic acid and OEA may prevent cancer formation by modulating the STAT pathway.
• Results offer new insights into the anti-cancer potential of oleic acid-rich oils like olive oil.