Rhus Verniciflua Stokes Inhibits PD-1 Expression and Induces Anticancer Effects by Enhancing T Cell Function.

Area of Science:

• Immunology
• Oncology
• Pharmacology

Background:

• Rhus verniciflua Stokes (RVS) has demonstrated anticancer effects in prior studies.
• The impact of RVS on immuno-oncology, particularly T cell function and phenotype, remains largely unexplored.
• Investigating RVS's role in modulating T cell responses is crucial for advancing cancer immunotherapy.

Purpose of the Study:

• To investigate the effects of RVS on immuno-oncology, focusing on T cell functional properties and phenotypes.
• To determine if RVS can enhance the anticancer activity of T cells against breast cancer.
• To explore the potential of RVS as a therapeutic agent for restoring T cell function in cancer patients.

Main Methods:

• Peripheral blood mononuclear cells (PBMCs) from breast cancer patients were used to generate cytokine-induced killer (CIK) cells.
• Anticancer activity of T cells was assessed against breast cancer cell lines (MCF-7, MDA-MB-231) using flow cytometry.
• T cell phenotype was analyzed by measuring PD-1 and CTLA-4 expression and key cytokine mRNA levels (IFN-γ, TNF-α, IL-2).

Main Results:

• RVS treatment significantly boosted T cell cytotoxicity against breast cancer cells, with a 20.6% increase against MCF-7 and 36.2% against MDA-MB-231 at 100 µg/mL.
• RVS administration led to a significant decrease in PD-1 expression on T cells.
• mRNA levels of IFN-γ, TNF-α, and IL-2 were analyzed to assess T cell activation.

Conclusions:

• RVS enhances T cell-mediated anticancer activity against breast cancer by downregulating PD-1 expression.
• These findings indicate that RVS components hold promise for revitalizing exhausted T cells in cancer immunotherapy.
• RVS may represent a novel therapeutic strategy to improve immune responses in cancer patients.