Fig. 4: The IRE1α kinase inhibitor KIRA6 blunts CXCL8 production after immunogenic treatment.

A CXCL8 secretion was measured by ELISA in conditioned medium of A375 cells 24 h after treatment with MTX in co-incubation with the PERK inhibitor GSK2606414 (1 μM) or the IRE1α kinase inhibitor KIRA6 (1 μM). B CXCL8 secretion was measured by ELISA in conditioned medium of A375 cells 24 h after treatment with MTX in co-incubation with the IRE1α RNAse inhibitors 4μ8C (100 μM) and STF-083010 (50 μM) or IRE1α kinase inhibitor KIRA6 (1 μM). C NF-κB activity measured by luciferase assay in A375 cells stably expressing the reporter 4 h after treatment with MTX in the presence or absence of KIRA6 (1 μM). Data are expressed as fold change compared to untreated control, indicated with a dotted line. D Impact of KIRA6 (1 μM) on intracellular levels of cJUN and cFOS in basal condition and 4 h after treatment with Hyp-PDT. β-actin was used as loading control. E, F CXCL8 secretion was measured by ELISA in conditioned medium of HeLa and HCT-116 cells 24 h after treatment with MTX in co-incubation with GSK2606414 (1 μM), KIRA6 (1 μM) or BAY11-7082 (10 μM). G CXCL1 secretion was measured by ELISA in conditioned medium of murine CT26 cells 24 h after treatment with MTX in co-incubation with GSK2606414 (1 μM), KIRA6 (1 μM), and BAY11-7082 (10 μM). In all graphs values are presented as mean ± SD of at least n = 3 independent biological replicates. Data are analyzed by one-way ANOVA followed by Dunnett’s multiple comparison test in all the graphs except for two-tailed Student’s t-test in (C, D). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.