PKP2 and primitive neuroectodermal tumor: We identified several components of desmosomes – Dsp, Dsg2, desmocollin 2 (Dsc2; MGI: 103221), and plakophilin 2 (Pkp2; MGI: 1914701) – whose expression was significantly downregulated in the highly invasive tumor lesions that develop in the RT2 mouse model of PNET.