Journal: Journal for immunotherapy of cancer
Article Title: Orlistat facilitates immunotherapy via AKT-FOXO3a-FOXM1-mediated PD-L1 suppression.
doi: 10.1136/jitc-2024-008923
Figure Lengend Snippet: Figure 3 Orlistat suppressed PD-L1 via inhibition of FOXM1 signaling. (A) Volcano plot of the expression of the reported transcription factors that regulated the expression of PD-L1. These TFs include STAT1, ATF3, IRF2, TFEB, IRF1, YY1, STAT3, JUN, HSF1, NFκB, SP1, FOXP3, BRD4, EZH2, MYC, HIF-1α, and FOXM1. (B, C) qRT-PCR measurement of mRNA expression of FOXM1 after orlistat (40 µM) treatment for 0 hour, 24 hours, or 48 hours in AGS and HCT116 (B), MC38 and CT26 cells (C). (D) WB analysis of FOXM1 protein levels after orlistat treatment for different times (0 hour, 24 hours, 48 hours) in AGS, HCT116, MC38, and CT26 cells. (E) Representative images of immunohistochemical staining of FOXM1 protein expression in resected tumors at day 25. Scale bar=50 µm. (F) The expression of PD-L1 mRNA in AGS and MC38 cells after transfection with FOXM1 overexpression or knockdown. (G) WB for PD-L1 protein levels after FOXM1 overexpression or knockdown in AGS and MC38 cells. (H) Schematic representation of the PD-L1 gene promoter regions and primer pairs used for ChIP assays. (I) ChIP-qPCR assay was used to detect the binding of FOXM1 to the PD-L1 promoter at the (+222 to +450 bp) region in AGS cells. (J) ChIP-qPCR analysis of the impact of orlistat (40 µM) on the binding of FOXM1 to the PD-L1 promoter. (K) The luciferase activity of PD-L1 promoter after FOXM1 overexpression with or without orlistat (40 µM). HEK293T cells in 24-well plates were transfected with FOXM1 plasmids or control. The luciferase activity was measured 36 hours later. *p<0.05, **p<0.01, ***p<0.001.
Article Snippet: Following activation, STAT1 (TargetMol, TMPJ- 00961) was immobilized on the sensor chip surface using a sodium acetate buffer (pH 5.0).
Techniques: Inhibition, Expressing, Quantitative RT-PCR, Immunohistochemical staining, Staining, Transfection, Over Expression, Knockdown, ChIP-qPCR, Binding Assay, Luciferase, Activity Assay, Control