GJA1 and neoplasm: Connexin-43 (Cx43), the main GJ protein expressed in immune cells [19], has been shown by us and other groups, to accumulate at immunological synapses, allowing GJ-mediated intercellular communications (GJIC) between lymphocytes and DCs [20,21,22,23], between cytotoxic cells (CTLs and NK cells) and tumor cells [22,23,24,25], and between DCs and tumor cells [26].