Journal: Breast Cancer Research : BCR
Article Title: Nuclear PD-L1 drives IFN-γ-promoted lung metastasis of triple-negative breast cancer via POLR2A-mediated transcriptional activation of LY6E
doi: 10.1186/s13058-025-02193-5
Figure Lengend Snippet: LY6E is identified as a key downstream effector of nuclear PD-L1 in metastasis. A Left: Venn diagram illustrating the strategy for identifying downstream targets of IFN-γ/nuclear PD-L1 from RNA-seq data of PD-L1 WT and KO 4T1 cells treated with or without 50 ng/mL IFN-γ for 24 h. Right: Heatmap of four candidate genes. B – C qPCR validation of Cldn1, Ly6e, Anxa8, and Gnb4 mRNA expression in the indicated treatment groups of 4T1 cells ( n = 4). D Western blot analysis of Claudin-1 and Ly6E protein expression in PD-L1 WT and KO 4T1 cells treated with or without 50 ng/mL IFN-γ for 24 h. E – F qPCR analysis of CLDN1 and LY6E mRNA expression in PD-L1 WT and PD-L1 KO MDA-MB-231 cells treated with or without 50 ng/mL IFN-γ for 48 h. G – H Western blot analysis of Claudin-1 and Ly6E protein expression in PD-L1 WT and KO MDA-MB-231 cells treated with or without 50 ng/mL IFN-γ for 48 h. I Analysis of LY6E and CD274 mRNA expression in TCGA TNBC tumor and adjacent normal tissue samples. J Correlation analysis of LY6E and CD274 mRNA expression in TCGA TNBC samples. K Representative images of lungs and quantification of metastatic nodules from LY6E overexpression cells. Data are presented as mean ± SD. Student’s t-test was used for two-group data analysis, while One Way ANOVA was used for multiple-group data analysis
Article Snippet: Proteins (20–30 μg) were separated by SDS-PAGE, transferred to nitrocellulose (NC) membranes, and probed with primary antibodies against PD-L1 (CST, #13684; #60475), POLR2A (CST, #2629), LY6E (Proteintech, 22144-1-AP), Claudin-1 (Proteintech, 13050-1-AP), STAT1 and phosphorylated STAT1 (CST, #14994; #9167), and GAPDH (Proteintech, 60004-1-Ig).
Techniques: RNA Sequencing, Biomarker Discovery, Expressing, Western Blot, Over Expression