In the search of MDM2 E3 ligase inhibitors to block in vitro proliferation of TGCT cell lines, that are mostly p53-wt, we subjected 2102EP(S), 2102EP(R), and NCCIT, three embryonal carcinoma TGCT cell lines, to a proliferation assay in the presence of increasing doses of sempervirine. Here, MDM2 is linked to embryonal carcinoma.