CCN2 in orofacial tissue development and remodeling

SummaryCCN2 is one of the representative members of the CCN family, a group of proteins that orchestrate the extracellular signaling network. As anticipated by the original name, connective tissue growth factor, this molecule promotes the growth and development of mesenchymal tissues, including bone and cartilage. Indeed, CCN2 is required for the proper development of the orofacial region, which requirement is typically suggested by the frequent emergence of cleft palate in CCN2-null mice. The significant contribution of CCN2 to mandibular morphogenesis and tooth germ development has also been indicated. Of note, CCN2 functions not only during development, but also later in life, as it is a critical promoter of physiological and pathological tissue remodeling, the latter of which denotes fibrotic reconstruction of tissue. In addition to its involvement in fibrotic disorders in a variety of organs, CCN2 has been also reported to be a mediator of periodontal fibrosis caused by several factors including smoking. Based on these cumulative findings, the utility of CCN2 to accelerate oral tissue regeneration by a harmonized remodeling process is discussed herein, together with regulation of the gene expression and molecular function of CCN2 as a therapeutic strategy against periodontal fibrosis.