**CCN Family: Matricellular Proteins in Cartilage and Bone Development**

John A. Arnott, Kathleen Doane and Sonia Lobo Planey

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/63199

#### **Abstract**

The extracellular matrix is the intricate scaffolding which surrounds and supports cells and helps to organize them into tissues and organs. The CCN family of matricellular proteins helps to regulate and modulate production, degradation, and remodeling of the extracellular matrix. In this chapter, we review the extracellular matrix of cartilage and bone, including an overview of chondrogenesis and skeletogenesis, and summa‐ rize the importance of the CCN proteins in establishment of the skeletal system. CCN proteins have both positive and negative regulatory roles in skeletal development, and their abnormal expression is related to the pathogenesis of several diseases observed in cartilage and bone that arise when inflammation or tissue injury becomes chronic, including fibrosis, arthritis, and cancer. Understanding the biological functions of the CCN proteins within this context offers opportunities for developing therapeutics by targeting CCN functions.

**Keywords:** matricellular proteins, CCN family, chondrogenesis; osteogenesis, extracellular matrix
