Claudin-12: guardian of the tissue barrier or friend of tumor cells

• Published in: Tissue barriers p. 2387408
• Main Authors: Apostolova, Desislava, Apostolov, Georgi, Moten, Dzhemal, Batsalova, Tsvetelina, Dzhambazov, Balik
• Format: Journal Article
• Language: English
• Published: United States 01.08.2024
• Subjects: Claudin-12; cell polarity; metastasis; paracellular permeability; Cancer
• ISSN: 2168-8370; 2168-8370
• DOI: 10.1080/21688370.2024.2387408

Tight junctions (TJs) are an important component of cellular connectivity. Claudin family proteins, as a constituent of TJs, determine their barrier properties, cell polarity and paracellular permeability. Claudin-12 is an atypical member of the claudin family, as it belongs to the group of non-classical claudins that lack a PDZ-binding domain. It has been shown that claudin-12 is involved in paracellular Ca transients and it is present in normal and hyperplastic tissues in addition to neoplastic tissues. Dysregulation of claudin-12 expression has been reported in various cancers, suggesting that this protein may play an important role in cancer cell migration, invasion, and metastasis. Some studies have shown that claudin-12 gene functions as a tumor suppressor, but others have reported that overexpression of claudin-12 significantly increases the metastatic properties of various tumor cells. Investigating this dual role of claudin-12 is of utmost importance and should therefore be studied in detail. The aim of this review is to provide an overview of the information available to date on claudin-12, including its structure, expression in various tissues and substances that may affect it, with a final focus on its role in cancer.