Periostin: novel diagnostic and therapeutic target for cancer.

Periostin is a secreted protein that shares a structural homology to the axon guidance protein fasciclin I (FAS1) in insects and was originally named as osteoblast-specific factor-2 (Osf2). Periostin is particularly highly homologus to Betaig-h3, which promotes cell adhesion and spreading of fibroblasts. It has recently been reported that Periostin was frequently overexpressed in various types of human cancers. Although the detailed function of Periostin is still unclear, Periostin-integrin interaction through FAS1 domain is thought to be involved in tumor development. In addition, Periostin stimulates metastatic growth by promoting cancer cell survival, invasion and angiogenesis. Therefore, Periostin can be a useful marker to predict the behavior of cancer. This review summarizes the recent understanding of Periostin roles in tumor development and speculates on the usefulness of Periostin as a therapeutic and diagnostic target for cancer.