The epithelium and the mesenchyme comprise the two important cellular partitions found in virtually every organ, and one influence the other via paracrine and cell-cell interactions. These epithelial-mesenchymal interactions have been shown to play important roles for normal tissue development during embryogenesis, and also exert crucial roles in the adult, being involved in roles as diverse as mammary gland development to skin homeostasis and repair. Studies have revealed that pathological disorders in these interactions may result in fibrogenesis and carcinogenesis, and a number of in vitro and in vivo models have been developed and employed to specifically investigate the epithelial-mesenchymal interactions in these scenarios. A thorough understanding of the roles of epithelial-mesenchymal interactions in tissue repair, fibrogenesis and carcinogenesis will facilitate and define the appropriate treatment for tissue fibrotic and carcinogenic states.
Keywords: extracellular matrix, matrix metalloproteinase, interleukin, insulin-like growth factor, Keloid-derived fibroblasts