Expression of LRP8 in gastric cancer and its significance in tumorigenesis

Background and purpose: Low-density lipoprotein receptor-related protein 8 (LRP8) plays an important role in the development of liver cancer, lung cancer, breast cancer, colorectal cancer and other tumors. This study aimed to explore the expression and prognostic role of LRP8 in gastric cancer, and evaluate the possibility of a new target for gastric cancer biotherapy. Methods: The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database were used to analyze the expression of LRP8 in gastric cancer tissues. The co-expressed gene with LRP8 in gastric cancer was analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. RNA interference (RNAi) was used for silencing the expression of LRP8 in AGS cell line, and functional assays were performed to evaluate the effects of LRP8 knockdown on theproliferation ability, invasiveness and the Wnt signaling pathway of AGS cell line in vitro. The relationship between LRP8 expression and prognosis of patients with gastric cancer was assessed by using Kaplan-Meier plotter database. To validate the 240 gastric cancer patients from TCGA database results, retrospective immunohistochemical analysis was performed to classify the relationship between the expression of LRP8 and clinical pathological features of 25 gastric cancer patients who underwent total or subtotal gastrectomy from August 2018 to July 2019 in the Fifth Affiliated Hospital of Zhengzhou University. Results: Data from the TCGA database showed LRP8 was overexpressed in gastric cancer tissues compared with normal gastric mucosa (P