LSD1 deletion represses gastric cancer migration by upregulating a novel miR-142-5p target protein CD9

Abstract

LSD1 (histone lysine specific demethylase 1) takes part in the physiological process of cell differentiation, EMT (epithelial-mesenchymal transition) and immune response. In this study, we found LSD1 expression in metastatic gastric cancer tissues was significantly higher than that in normal tissues. Furthermore, LSD1 deletion was found to suppress gastric cancer migration by decreasing intracellular miR-142−5p, which further led to the upregulation of migration suppressor CD9, a newly identified target of miR-142−5p. While LSD1 was reported as a demethylase of H3K4me1/2, H3K9me1/2 and several non-histone proteins, this is a new evidence for LSD1 as a functional regulator of miRNA. On the other hand, our data suggested that promoting the secretion of miR-142−5p using small extracellular vesicles as vehicles is a new mechanism for LSD1 abrogation to down-regulate intracellular miR-142−5p. Taken together, this study uncovered a new mechanism for LSD1 that can contribute to gastric cancer migration by facilitating miR-142−5p to target CD9.