Targeting lectin-like oxidized low-density lipoprotein receptor-1 triggers autophagic program in esophageal cancer

Abstract

Autophagy is a highly conserved catabolic process to maintain cellular homeostasis. However, dysfunctional autophagy contributes to a context-dependent role in cancer. Here, we clarified the exact role of autophagy modulated by the scavenger receptor lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) in esophageal cancer (EC). A comprehensive analysis in various cancers displayed that LOX-1 was upregulated the most in EC tissues and associated with poor prognosis of patients. Deletion of LOX-1 ex vivo and in vivo suppresses EC development by inducing autophagic cell death. Receptor for activated C kinase 1 (RACK1) was identified as a signal adapter of LOX-1, which incented RAS/MEK/ERK pathway and TFEB nuclear export signal and safeguarded tumorigenesis. A sulfated polysaccharide fucoidan extracted from brown seaweed was found to bind with LOX-1 and mediate its proteasomal degradation but not the lysosome pathway, leading to autophagy-related cell death in EC. These results reveal a central contribution of LOX-1 to EC development and provide genetic ablation or bioactive polysaccharide as an effective intervention for EC therapy.