Effect of oridonin-mediated hallmark changes on inflammatory pathways in human pancreatic cancer (BxPC-3) cells

To investigate the effect of oridonin on nuclear transcription factors and to study the relationship between biological behavior and inflammatory factors in human pancreatic cancer (BxPC-3) cells.

BxPC-3 cells were treated with various concentrations of oridonin, and viability curves were generated to test for inhibitory effects of the drug on cells. The expression of cytokines such as interleukin-1β (IL-1β), IL-6, or IL-33 was detected in BxPC-3 cell supernatants using an enzyme-linked immunosorbent assay (ELISA), and the protein expression of nuclear transcription factors including nuclear factor κB, activating protein-1, signal transducer and activator of transcription 3, bone morphogenetic protein 2, transforming growth factor β1 and sma and mad homologues in BxPC-3 cells was detected using Western blot. Carcinoma hallmark-related proteins such as survivin, vascular endothelial growth factor, and matrix metallopeptidase 2 were also detected using immunoblotting, and intra-nuclear IL-33 expression was detected using immunofluorescent staining.

Treatment with oridonin reduced the viability of BxPC-3 cells in a dose dependent manner. The cells exhibited reduced growth following treatment with 8 μg/mL oridonin (13.05% ± 3.21%, P < 0.01), and the highest inhibitory ratio was 90.64% ± 0.70%, which was achieved with oridonin at a dose of 32 μg/mL. The IC50 value of oridonin in BxPC-3 cells was 19.32 μg/mL. ELISA analysis revealed that oridonin down-regulated the inflammatory factors IL-1β, IL-6, and IL-33 in a dose-dependent manner. IL-1β expression was significantly reduced in the 16 and 32 μg/mL treatment groups compared to the control group (12.97 ± 0.45 pg/mL, 11.17 ± 0.63 pg/mL vs 14.40 ± 0.38 pg/mL, P < 0.01). Similar trends were observed for IL-6 expression, which was significantly reduced in the 16 and 32 μg/mL treatment groups compared to the control group (4.05 ± 0.14 pg/mL vs 4.45 ± 0.43 pg/mL, P < 0.05; 3.95 ± 0.13 pg/mL vs 4.45 ± 0.43 pg/mL, P < 0.01). IL-33 expression was significantly reduced in the 8, 16, and 32 μg/mL treatment groups compared to the control group (911.05 ± 14.18 pg/mL vs 945.25 ± 12.09 pg/mL, P < 0.05; 802.70 ± 11.88 pg/mL, 768.54 ± 10.98 pg/mL vs 945.25 ± 12.09 pg/mL, P < 0.01). Western blot and immunofluorescent staining analyses suggested that oridonin changed the hallmarks and regulated the expression of various nuclear transcription factors.

The results obtained suggest that oridonin alters the hallmarks of pancreatic cancer cells through the regulation of nuclear transcription factors.