Since FS1 and TCam-2 cells seem to be promising tools for coculture experiments in context with seminoma development [51, 58], we aimed to further characterize both cell lines focusing on the junctional proteins Cx43, Cx45 and N-cadherin, as intercellular adhesion and communication might play a role in progression of the precursor stage GCNIS to invasive seminoma. Here, GJA1 is linked to seminoma.