Journal: Frontiers in Immunology
Article Title: Identifying the therapeutic potential of niclosamide in overcoming IFN-gamma dependent cancer immune evasion in the tumor microenvironment
doi: 10.3389/fimmu.2026.1761715
Figure Lengend Snippet: IFNγ up-regulate PD-L1 expression in MC38 cells through IFN-STAT1 signaling. PD-L1 expression on MC38 cell surface was significantly increased in the presence of IFN-γ analyzed by flow cytometry (A) and by immune fluorescent staining (B-C) at 24 hours. (D) When treated with siRNA of STAT1, the up-regulation of PD-L1 was significantly reduced, while siRNA of STAT3 has an opposite effect. (E, F) The small interfering RNA reaches a sufficient knock down of STAT1 and STAT3, as shown by real-time PCR assay. (G-I) The mRNA of STAT1 target genes such as CXCL10 and IL-15 shown similar trend of regulation by IFN-γ as PD-L1. (J) The mRNA of STAT3 target gene, MCL-1, shown totally different regulation under normal condition and under treatment of siRNAs. (K, L) The expression of STAT1/STAT3 normal and phosphorylated proteins, and PD-L1 proteins in MC38 cell lines were measured by Western blotting with different dose of IFN-γ stimulation (K) or after knocking down of STAT1 (siSTAT1) or STAT3 (siSTAT3) (L ). The number on the image indicates the relative abundance of PD-L1 protein (fold of control). The results are expressed as the mean ± SEM of triplicate measurements in each group. *p<0.05, **p<0.01, ***p<0.001.
Article Snippet: STAT1 inhibitor Fludarabine (F-ara-A, NSC 118218) (MedChemExpress, Cat. No.: HY-B0069) and STAT3 inhibitor Niclosamide (BAY2353, MedChemExpress, Cat. No.: HY-B0497) were purchased from MedChemExpress (Monmouth Junction, NJ, USA).
Techniques: Expressing, Flow Cytometry, Staining, Small Interfering RNA, Knockdown, Real-time Polymerase Chain Reaction, Western Blot, Control