Tight junctions and their role in cancer metastasis

Tight Junctions govern the permeability of endothelial and epithelial cells and are the most topical structures of these cell types. Tight junctions c reate an intercellular barrier and intramembrane diffusion fence. An import ant step in the formation of cancer metastases is interaction and penetrati on of the vascular endothelium by dissociated cancer cells. Early studies demonstrated a correlation between the reduction of tight jun ctions and tumour differentiation and experimental evidence has emerged to place tight junctions in the frontline as the structure that cancer cells m ust overcome in order to metastasise. Changes in tight junction function ar e thus an early and key aspect in cancer metastasis. Further work is required to fully realise the potential that this structure has in cancer invasion and metastasis in order to develop new and novel th erapies in the prevention of tumour metastasis.