ABSTRACT
This chapter describes the role of gap junctions in cell-to-cell communication, especially in cancer initiation and progression, is reviewed with a focus on 3D systems. The diffusion of molecules between adjacent cells through gap junctions is termed gap junctional intercellular communication (GJIC). On the membrane, the connexon floats laterally until it docks with a second connexon on the adjacent cell to form an intact gap junction channel. Multiple studies confirmed that a deficiency in gap junctions, and thus GJIC, is associated with the cancer phenotype. The chapter covers why only some cancers express connexins at early stages. Other reports have suggested that it may be due to a lack of cell-cell recognition. Current approaches for the development of in vitro tumor models aim to recapitulate the native microenvironment of gap junctions in vivo using 3D scaffolds in order to create better preclinical cancer models.
