Abstract 5166: Lysyl oxidase regulates cell surface EGFR, and directionality of cancer cell invasion

Abstract

Abstract Lysyl oxidase (LOX) remodels the tumour microenvironment by cross-linking the extracellular matrix. LOX overexpression is associated with poor cancer outcomes. We find that LOX regulates the epidermal growth factor receptor (EGFR) to drive tumour progression. LOX regulates EGFR by suppressing TGFβ1 signalling through the secreted protease HTRA1. This increases the expression of Matrilin2 (MATN2), an EGF-like domain containing protein that traps EGFR at the cell surface to facilitate its activation by EGF. A novel pharmacological inhibitor of LOX, CCT365623, disrupts EGFR cell surface retention in vitro and delays the growth of primary tumour cells in vivo. In addition to its role in controlling primary tumour growth, LOX expression is also implicated in the processes of cancer cell invasion, and thereby the process of metastasis. Notably, we find that when LOX is depleted or inhibited, cancer cells are no longer able to sence a chemo-attractive gradient, and invade in a directional manner. Importantly, LOX produced by both cancer cells and fibroblasts can mediate this behaviour. Together, we show that LOX regulates EGFR cell surface retention to drive tumour progression. We also find that LOX does not regulate cancer cell invasion per se, but rather that it regulates the directionality of cancer cell migration, and both the cancer and stromal cells appear to contribute to this behaviour. Citation Format: Haoran Tang, Caroline Springer, Richard Marais. Lysyl oxidase regulates cell surface EGFR, and directionality of cancer cell invasion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5166.