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.
Subject(s)
Cell Movement , Gene Deletion , Histone Demethylases/metabolism , MicroRNAs/metabolism , Stomach Neoplasms/enzymology , Tetraspanin 29/metabolism , Animals , Cell Line, Tumor , Extracellular Vesicles/genetics , Extracellular Vesicles/metabolism , Female , Gene Expression Regulation, Neoplastic , HEK293 Cells , Histone Demethylases/genetics , Humans , Mice, Inbred BALB C , Mice, Inbred NOD , Mice, Nude , Mice, SCID , MicroRNAs/genetics , Neoplasm Invasiveness , Neoplasm Metastasis , Signal Transduction , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Tetraspanin 29/geneticsABSTRACT
Natural protoberberine alkaloids were first identified and characterized as potent, selective and cellular active lysine specific demethylase 1 (LSD1) inhibitors. Due to our study, isoquinoline-based tetracyclic scaffold was identified as the key structural element for their anti-LSD1 activity, subtle changes of substituents attached to the core structure led to dramatic changes of the activity. Among these protoberberine alkaloids, epiberberine potently inhibited LSD1 (IC50 = 0.14 ± 0.01 µM) and was highly selective to LSD1 over MAO-A/B. Furthermore, epiberberine could induce the expression of CD86, CD11b and CD14 in THP-1 and HL-60 cells, confirming its cellular activity of inducing acute myeloid leukemia (AML) cells differentiation. Moreover, epiberberine prolonged the survival of THP-1 cells bearing mice and inhibited the growth of AML cells in vivo without obvious global toxicity. These findings give the potential application of epiberberine in AML treatment, and the isoquinoline-based tetracyclic scaffold could be used for further development of LSD1 inhibitors.