Fig. 7

MS-275 enhances HLA-E expression through acetylation of STAT3. A A Venn diagram showing the analysis of the KnockTF, ENCODE, and ChIP-Atlas databases revealed 56, 113, and 422 HLA-E transcription factors, respectively. Intersection analysis identified 11 most likely HLA-E transcription factors, including JUND, NFYA, NFYB, RELA, RFX5, RNF2, STAT1, STAT2, STAT3, STAT5A and TRIM28. B-C Lollipop chart showing correlation analysis between 11 potential transcription factors (JUND, NFYA, NFYB, RELA, RFX5, RNF2, STAT1, STAT2, STAT3, STAT5A, and TRIM28) and HLA-E expression in BSG (B) or DMG (C) patients. The point size represents the correlation coefficient. D Integrated Genomics Viewer (IGV) screenshot showing the results of STAT3 ChIP-seq in peaks at the genomic regions of HLA-E. E Analysis of the JASPAR database showing the potential binding region of STAT3 to the HLA-E promoter. F The protein expression of HLA-E and total STAT3 in TT150630 cells expressing sh-NC or sh-STAT3 was detected via Western blotting. β-Actin was used as the internal control (left). The quantified results are presented in the plot (right). Statistical significance was assessed via one-way ANOVA with **p < 0.01 and ***p < 0.001. G HLA-E expression on the cell surface of TT150630 cells expressing sh-NC or sh-STAT3 was detected via flow cytometry. The quantification of the results is shown on the right. Statistical significance was assessed via one-way ANOVA with ****p < 0.0001. H TT150630 cells treated with MS-275 (1 μM) or DMSO for 2 days were analyzed for STAT3 recruitment to the HLA-E promoter via ChIP analysis. The ChIP results are shown as the fold change relative to the IgG control. Statistical significance was assessed via Student’s t test, with **p < 0.01 and ***p < 0.001. I The protein expression of HLA-E, total STAT3, p-STAT3 (S727), p-STAT3 (Y705), and ac-STAT3 (K685) in TT150630 and TT190326 cells treated with 1 μM MS-275 for 2 days was detected via Western blotting. β-Actin was used as the internal control. J The protein expression of HLA-E, total STAT3, p-STAT3 (S727), and p-STAT3 (Y705) in TT150630 and TT190326 cells treated with 1 μM Stattic for 2 days was detected via Western blotting. β-Actin was used as the internal control. K The protein expression of HLA-E, total STAT3, and ac-STAT3 (K685) in TT150630 cells or TT190326 cells expressing sh-NC or sh-STAT3 treated with DMOS or 1 μM MS-275 for 2 days was detected via Western blotting. β-Actin was used as the internal control