Recently, an evaluation of the expression of these seven selenoproteins in human cancer cell lines DU145 (prostate carcinoma), MCF7 (breast adenocarcinoma) and HT-1080 (fibrosarcoma) after treatment with the Se-derived anti-cancer agent MSA [117,118] revealed that the expression pattern of SELENOM is opposite to SELENOT and SELENOF, which implicates the prioritization of Se and selenoprotein synthesis to allow for sorting according to the cell state [119]. Here, SELENOS is linked to fibrosarcoma.