ZO-1 is proangiogenic

What is it about?

Zonula occludens-1 (ZO-1) is a tight junction protein located at the cell membrane. In some conditions, as in cancer, it can be shutlled to cytoplasm and nucleus. In this context, we have shown that interleukin-8 (IL-8) expression is upregulated by ZO-1 when it is cyto-nuclear. Decipherment of this regulation by in vitro analyses have revealed that ZO-1 controls IL-8 level by a dependant mechanism of the NF-kB transcription factor. More, with murin in vivo models we have shown the pro-angiogenic abilities of this regulation axis, that have been correlated on human lung tumor samples.

Featured Image

Why is it important?

This work supports the concept that ZO-1 is more than a architectural protein. If it plays a central structural role in establishment of cell-cell junctions, ZO-1 acts also as signaling protein outside the perimeter of the membrane. The ZO-1 shuttle from the cell junction to the cyto-nuclear compartment may affect both the intrinsic invasive properties of tumor cells and the establishment of the pro-tumoral microenvironment.