MIR-29B REGULATES CELL PROLIFERATION AND INVASION IN HUMAN OVARIAN CLEAR CELL CARCINOMA BY TARGETING LYSYL OXIDASE (LOX)

Ovarian cancer is the leading cause of death from gynecologic cancer, reflecting its chemoresistance and frequent late diagnosis, and suggesting that a more effective treatment approach is needed. Lysyl oxidase (LOX) is involved in important biological processes such as gene regulation, cell signaling and cell motility, its deregulation contributing to tumor formation and development. Although it is known that LOX is involved in proliferation, migration and invasion in several types of tumors, studies of LOX in ovarian cancers are scarce. To explore the molecular regulation mechanisms in ovarian cancer tumorigenesis, the expression change and the function of LOX was confirmed in ovarian tissues and cells, which suggested that LOX is a tumor suppressor gene. To further understand how LOX expression is regulated in ovarian cancer, microRNAs (miRNAs) were considered because of their role in post-transcriptional regulation of many genes. Recent work has described differential expression of mature miRNAs in human cancers. Bioinformatics prediction which was used to find the appropriate miRNA regulating LOX, revealed that miR-29b regulates LOX protein level via its binding site on the 3'UTR of LOX mRNA in ES-2 cells, a human ovarian clear cell carcinoma cell line. miR-29b knockdown inhibited proliferation and invasion in ES-2 cells. Taken together, these findings suggest that influencing LOX regulation by changing the level of miR-29b expression could provide a novel potential approach for treating human ovarian clear cell carcinoma.