Silencing of FAM111B inhibits tumor growth and promotes apoptosis by decreasing AKT activity in ovarian cancer

Abstract

Ovarian cancer is the most lethal gynecological tumor in women worldwide. FAM111B (family with sequence similarity 111 member B) is an oncoprotein associated with multiple cancers, but its biological functions in ovarian cancer remain elusive. In this study, FAM111B was overexpressed in ovarian cancer tissues and cell lines. Functional studies in vitro revealed that silencing of FAM111B inhibited ovarian cancer cell proliferation, invasion, and migration, as well as increased cell apoptosis. Furthermore, FAM111B silencing arrested the ovarian cancer cell cycle at the G1/S phase. Furthermore, western blot assays demonstrated that silencing of FAM111B resulted in downregulation of phospho-AKT (p-AKT) protein expression, as well as upregulation of p53 and caspase-1 protein expression. The xenograft animal model of ovarian cancer demonstrated that FAM111B silencing inhibited tumor growth, enhanced cell apoptosis, and inhibited Ki-67 and proliferating cell nuclear antigen (PCNA) protein expression in vivo. Conversely, the overexpression of FAM111B exhibited opposite effects on the ovarian cancer xenograft. It was previously established that inactivating AKT inhibited ovarian cancer progression. This study found that silencing of FAM111B inhibits tumor growth and promotes apoptosis by decreasing AKT activity in ovarian cancer. Caspase-1 and p53 signaling also influenced the function of FAM111B in SKOV3 cells. Collectively, our results demonstrate that silencing of FAM111B is a potential therapeutic strategy against ovarian cancer.

Unravelling the Intricate Roles of FAM111A and FAM111B: From Protease-Mediated Cellular Processes to Disease Implications

“…Furthermore, the direct or indirect activation of FAM111B by p53 has also been reported [ 22 ]. Moreover, it has been previously shown that the knockout or silencing of FAM111B affects the expression of p53 and p53-related proteins, such as p16, BAG3, BCL-2, CCNB1 [ 22 , 23 , 24 ], AKT and caspase-1 [ 23 ]. Therefore, in addition to FAM111B’s role in DNA repair, its proposed cellular function can be extended to cell cycle regulation.…”