Acetyl-Claudin-9 – Ion Channels and Transporters

Acetly-Claudin-9 is derived from the tight junction protein Claudin-9 which is encoded by the CLDN6 gene and can be found within epithelial cell to cell contacts. Structurally, the Claudin family, of which Claudin-9 is a member, are transmembrane proteins containing two extracellular loops and are involved in maintaining cell polarity and controlling paracellular ion flux. Reduction in the number of Claudins has been associated with tumour formation. This may be due to Claudin role in maintaining cell detachment and migration. Claudin-9 has been shown to be overexpressed in hepatocellular carcinoma (HCC) and has the ability to increase the metastasis of hepatocytes. It further influences the activation of the Stat3 signalling pathway through tyrosine kinase 2. Overall CLDN9 demonstrates itself to be a HCC proto-oncogene.