Ras-related protein Rab-40B (RAB40B)

Ras-related protein Rab-40B (RAB40B) is a member of the Rab family of small GTPases, functioning as an adaptor in ECS E3 ubiquitin ligase complexes and regulating intracellular vesicle trafficking, particularly in secretory pathways. It cycles between an inactive GDP-bound and an active GTP-bound state, orchestrating vesicle formation, movement, and fusion by recruiting effector proteins. RAB40B activity regulates actin cytoskeleton dynamics and extracellular matrix degradation, impacting cancer cell migration and invasion. Overexpression of RAB40B has been linked to cancer progression, especially in hepatocellular carcinoma, where it drives cell proliferation and metastasis through the PI3K/AKT signaling axis and upregulation of cell cycle-related proteins and metalloproteinases. Knockdown or inhibition suppresses tumor growth, induces cell cycle arrest, and promotes apoptosis, highlighting its role as a potential therapeutic target in oncology[1][2][3].

Other names

SEC4LProtein RarRARSOCS box-containing protein RARGTP-binding protein homologous to Saccharomyces cerevisiae SEC4

Inhibition of RAB40B reduces cell proliferation, migration, and invasion by downregulating cyclin D1, cyclin E1, and MMP2 via the PI3K/AKT pathway; promotes apoptosis and cell cycle arrest