biostudies-literatureUnknown29(22)Hsieh MJThis research did not receive external funding.Quinovic acid is a key constituent of cat's claw (Uncaria tomentosa) extract and exhibits antioxidant and anti-inflammatory activities. In this study, we investigated the potential of quinovic acid to enhance natural killer (NK) cell activity by using the KHYG-1 cell line. Our data indicated that quinovic acid increased the expression levels of cytolytic molecules, including perforin, granzymes A and B, Fas ligand, and granulysin, and induced the phosphorylation of the transcription factors CREB and STAT4, thereby enhancing cytotoxic activity against K562 cells. Furthermore, when KHYG-1 cells were cocultured with K562 cells in the presence of quinovic acid, we observed an increase in the expression of t-Bid, cleaved caspases 3, 8, and 9, and PARP, promoting apoptosis in K562 cells. QuinoviJournal of cellular and molecular medicinee70957https://www.ebi.ac.uk/biostudies/studies/S-EPMC12648300biostudies-literatureQuinovic Acid Enhances the Cytotoxicity of KHYG-1 Cells by Modulating the Ras/MAPK Signalling Pathway and Interferon-Gamma Expression.PMC12648300Hsieh MJLin JTHo HYLin CCLo YSChen MKChuang YCfalseQuinovic Acid Enhances the Cytotoxicity of KHYG-1 Cells by Modulating the Ras/MAPK Signalling Pathway and Interferon-Gamma Expression.Quinovic acid is a key constituent of cat's claw (Uncaria tomentosa) extract and exhibits antioxidant and anti-inflammatory activities. In this study, we investigated the potential of quinovic acid to enhance natural killer (NK) cell activity by using the KHYG-1 cell line. Our data indicated that quinovic acid increased the expression levels of cytolytic molecules, including perforin, granzymes A and B, Fas ligand, and granulysin, and induced the phosphorylation of the transcription factors CREB and STAT4, thereby enhancing cytotoxic activity against K562 cells. Furthermore, when KHYG-1 cells were cocultured with K562 cells in the presence of quinovic acid, we observed an increase in the expression of t-Bid, cleaved caspases 3, 8, and 9, and PARP, promoting apoptosis in K562 cells. Quinovi2025-01-01T00:00:00Z2025 Nov2026-06-05T17:54:38.797Z2026-05-19T03:11:56.014ZS-EPMC126483004129404310.1111/jcmm.70957