Fig. 3

IGFBP3 increases PD-L1 expression by up-regulating the phosphorylation of STAT3 in GBM cells. A KEGG analysis of differential genes. B Correlation analysis of IGFBP3 and STAT3 in TCGA and CGGA databases, and statistical significance was assessed using the spearman’s rank test. C Immunoblotting analysis of IGFBP3, p-JAK2, p-STAT3, and PD-L1 expression in U251 cell treated with different concentrations of IGFBP3 for 24 h. D Immunoblotting analysis of IGFBP3, p-JAK2, p-STAT3, and PD-L1 expression in U251 cells infected with IGFBP3 overexpressing and empty vector lentivirus. E Immunoblotting was performed to examine the expression of IGFBP3, p-JAK2, p-STAT3, and PD-L1 in LN229 cell transfected with si-IGFBP3 and si-NC. F Immunoblotting analysis of IGFBP3, p-JAK2, p-STAT3, and PD-L1 expression in LN229 cell infected with sh-IGFBP3 and sh-con. G LN229 and T98G cells with IGFBP3 knockdown were treated with the JAK2/STAT3 inhibitor WP1066 for 24 h, cell lysate was used to analyze the expression of p-JAK2, p-STAT3 and PD-L1. H Immunoblotting was used to analyze the expression of IGFBP3, p-STAT3, and PD-L1 in STAT3-silenced LN229 and T98G cells stimulated with different concentrations of exogenous IGFBP3 for 24 h