Fig. 7

CD147 promotes the expression of CXCL1 by activating the transcriptional activity of AP-1. A Overexpression of CD147 increases AP-1 luciferase activity in keratinocytes. CD147 was transfected with pGL3-AP-1 or pGL3-ctrl plasmids containing the Renilla luciferase reporter gene, and the AP-1 activity was assessed by luciferase assay. Data from multiple experiments are expressed as the mean ± SD (n = 3). The significance of differences was evaluated using one-way ANOVA. B-C CD147 elevates AP-1 DNA binding activity in keratinocytes. Nuclear protein was extracted from CD147-overexpressing JB6 (B upper panel) and CD147-deficient HaCaT cells (C upper panel) treated with EGF and subjected to an EMSA. Bar charts of the average fluorescence intensity of AP-1 in JB6 (B lower panel) and HaCaT cells (C lower panel) were presented. Data were shown as the mean ± SD. The significance of differences was evaluated using two-way ANOVA. D CD147 enhances AP-1 association with CXCL1 promoter. Schematic diagram of the CXCL1 (D upper panel) promoters, and PROMO predicted several binding sites of AP-1. ChIP assays were performed to examine AP-1 recognition of the CXCL1 promoters (D lower panel). Data from multiple experiments are expressed as the mean ± SD (n = 3). The significance of differences was evaluated using Student’s t-test. The data of Primer 1 and Primer 2 were not shown as the experiment did not work. E-F The expression of CD147 correlates with the levels of CXCL1 in keratinocytes. CD147-overexpressing JB6 cells (E) and CD147-deficient HaCaT cells (F) were stimulated with EGF for 30 min and subjected to RT-PCR analysis of CXCL1. Data are presented as the mean ± SD. The significance of differences was evaluated using Student’s t-test