The role of periostin in neoplastic processes.

Periostin, also called osteoblast-specific factor 2 (OSF-2), is a multifunctional glycoprotein that belongs to the group of matricellular proteins. Due to its characteristic molecular structure containing integrin-binding domains, periostin is capable of binding to multiple integrin receptors (αvβ3, αvβ5, α6β4), thus affecting the regulation of the intracellular signaling pathways associated with protein kinases PI3K/AKT and focal adhesion kinase (FAK). This protein thus plays a role in the adhesion process, in the migration of many cells, and importantly, epithelial-mesenchymal transition of cancer cells. Periostin also participates in the processes of angiogenesis and lymphangiogenesis, metastases of cancer cells, and remodeling of the extracellular matrix. Increased expression of periostin has been observed in various tumor types, including breast, NSCLC, colorectal, pancreatic, prostate, and ovarian cancers, as well as tumors of the head and neck, and glioblastomas. Many groups have recently reported on periostin's key role in tumor progression, which suggests that periostin can be considered a potential therapeutic target.