Abstract 2634: Vasoactive intestinal polypeptide (VIP) regulates ZEB1 expression in cancer

Abstract

Abstract Background: In cancer immunology, VIP is a neuropeptide with pleiotropic effects that include inhibiting T cell activation, increasing Treg frequency, and augmenting the myeloid-derived suppressor cells function. VIP expression by cancer may represent a paracrine immune-checkpoint pathway while simultaneously having autocrine effects on cancer growth. We used an in silico model to identify genes whose over-expression in cancer was correlated with VIP expression and confirmed the role of VIP receptor (VIPR) signaling in vitro using VIPR inhibitors. Methods: The TCGA PanCan dataset (UCSC Xena) was used to compare mRNA expression data of VIP versus 760 genes involved in 48 cancer related pathways. Associations by cancer histology and germ layer were calculated. A Pearson’s Coefficient cutoff of R > [0.3] defined a significant gene association. VIP and target gene expression were confirmed and quantified by western blot analysis in cancer cell lines and VIPR signaling was inhibited using ANT008, a novel VIPR inhibitor. Results: Significant associations were observed between VIP expression and 10 genes (Table 1). Strong associations (R > [0.4]) were observed in cancers derived from ectodermal and mesodermal germ layers. The strongest gene association was for VIP and ZEB1 in stomach adenocarcinoma (STAD, R = 0.7643). In vitro experiments using Jurkat T cells confirmed expression of VIP and ZEB1 proteins. Treatment with the VIPR inhibitor ANT008 (10μM) reduced VIP and ZEB1 protein expression by 50%. A similar fold increase in ZEB1 expression was observed with exogenous VIP. PCR studies are currently underway. Conclusions: The results demonstrate autocrine signaling between VIP expression and cancer associated gene pathways. ZEB1 is a known EMT (epithelial mesenchymal transition) regulator, and our in vitro studies novelly link VIP to EMT and demonstrate that this pathway is therapeutically targetable using a VIPR inhibitor. Further studies in the pertinent tumor histologies are warranted. Table 1. Genes All Samples Ectoderm (All) Mesoderm (All) Endoderm (All) MAPK3 0.3120 0.3537 0.2252 0.3380 ZEB1 0.3621 0.4341 0.4901 0.3348 NOS2 0.3611 0.3186 0.4849 0.3428 TEK 0.3113 0.3336 0.5131 0.2600 PTCH1 0.3031 0.4040 -0.0061 0.2879 EI4G1 -0.3216 -0.4268 -0.3779 -0.2064 GMPS -0.3074 -0.4698 -0.3005 -0.0928 CDK2 -0.3186 -0.4687 -0.2345 -0.0563 RUVBL1 -0.3135 -0.3270 -0.4716 -0.1886 TIMELESS -0.3036 -0.4284 -0.3717 -0.1505 Citation Format: Ishani H. Rao, Rohan Dhamsania, Edmund K. Waller, Sanjay Chandrasekaran. Vasoactive intestinal polypeptide (VIP) regulates ZEB1 expression in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2634.