Fig. 2: IRhom1 negatively regulates antigen presentation and antitumor immune response.
From: Inhibition of iRhom1 by CD44-targeting nanocarrier for improved cancer immunochemotherapy
a TCGA analysis of iRhom1 gene expression levels in various cancer subtypes. TNBC: triple negative breast cancer; non-TNBC: breast cancer patients other than TNBC patients; MSI-H: microsatellite instability-high; MSI-L: microsatellite instability-low; MSS: microsatellite stable. n (TNBC) = 115, n(non-TNBC) = 653, n(MSI-H) = 78, n(MSI-L) = 76, n(MSS) = 267. b Tumor growth curves of WT, iRhom1 KO, iRhom1 rescue and vector control CT26 cells in immunodeficient (n = 4 mice) or immunocompetent mice (n = 5 mice). c Activation of immune-related signaling pathways in iRhom1−/− CT26 cells (RNAseq analysis). d Flow analysis of H2Kb/SIINFEKL presentation on B16-OVA and iRhom1 KO B16-OVA (B16-OVA KO) cells, with or without re-expression of iRhom1 (+piRhom). n = 3 independent samples. e Cytolysis of WT or iRhom1 KO B16-OVA cells co-cultured with CD8+ T cells isolated from spleens of OT-I mice, with or without blockade by H2K antibody (H2K Ab). n = 3 independent samples. f The correlation of protein expression levels between iRhom1 and various APP-related proteins in the tumor samples of TNBC patients. n = 25. g Changes in ERAP1 protein levels in various cancer cell lines following iRhom1 KO and OE. h Co-Immunoprecipitation of HA-iRhom1 with anti-HA antibody led to pulldown of ERAP1 in HA-iRhom1 expressing 293 T cells and reciprocal immunoprecipitation of GFP-ERAP1 with anti-GFP beads led to pulldown of iRhom1 in GFP-ERAP1 expressing 293 T cells. i Changes in ERAP1 protein levels in iRhom1 WT, KO and OE cells after treatment with Eeyarestatin I (4.5 μM). j The stability (t1/2) of ERAP1 in iRhom1 WT and KO cells determined by cycloheximide chase experiment. The experiment was repeated three times independently and data were quantified by densitometry. k Representative WB of ERAP1 protein levels in cycloheximide chase experiments. Data are presented as mean ± s.e.m. in (b, d, e, j). Statistical analysis was performed by two-tailed Student’s t test for comparison in (a (upper panel), b (immunodeficient)), and one-way ANOVA with Tukey’s post hoc test for comparison in (a (lower panel), b (immunocompetent), d and e). Data are representative of two independent experiments in (b, c, d, e, g–i) and three independent experiments in (j, k). Source data are provided as a Source Data file for (b, d, e, g, h, i, j, k).
