Search

The Autocrine Motility Factor (AMF) identified as a tumor cell motile stimulation factor is a key molecule of invasion and metastasis. The AMF is also identified as neuroleukin (NLK) and maturation factor (MF) which are secreted phosphohexose isomerase (PHI, PGI) from anaplastic cells. Tumor AMF promotes cellular locomotion or invasion, and regulates tumor MMPs secretion or apoptotic resistance. The AMF was thought to be an autocrine factor as the name shows it, and it is peculiar to malignant cells. However we found paracrine effect of AMF against tumor surrounding host tissues. Especially, endothelial cells which are essential parts of tumor induced angiogenesis or ascites accumulation express the AMF-receptor and they responded to AMF stimulation. Metastasis is a most complicated biological phenomenon that a large number of molecules or factors induced by tumor and host are related, thus AMF is also unusual molecule reacting between tumor and host tissues, and therefore AMF should be a target of treatment or diagnosis of cancer.

Locomotion of tumor cells and its regulation are thought to be crucial for metastasis. Autocrine motility factor (AMF) is a cytokine which stimulates in vitro motility and in vivo lung-colonizing ability of tumor cells via a receptor, a cell surface glycoprotein of 78kD (gp78)-mediated signaling pathway. AMF induces gp78 internalization to intracellular tubulovesicles including lysosome and transport to the leading edge. The AMF-gp78 complex internalization from the cell surface is involved in control of cell motility during metastasis.