RESUMO
Periostin (POSTN), an osteoblast-specific secreted protein known to be associated with cell adhesion activity for bone formation and development by the epithelial cell-derived tumors, leads to a significant enhancement in angiogenesis and tumorigenesis. At present, little is known about the mechanisms underlying its transcriptional control either in physiological or neoplastic conditions. In this study we demonstrate that the ability of the human POSTN promoter to drive transcription mostly depends on the activity of YingYang-1 (YY1) zinc finger transcription factor. YY1, whose regulatory role in biology includes, besides transcriptional control, also chromatin remodeling, DNA damage repair and tumorigenesis, acts as a strong negative modulator of the POSTN expression. We retain that the identification of the functional role of YY1 in the transcriptional control of the human POSTN gene adds new insights in the studies focused on gene expression in normal and transformed cells.