GPX4 and neoplasm: Notably, among these selenoproteins, considering only the two TNBC cell lines (MDAMB231 and MDAMB468) compared to normal epithelial breast MCF10A cells, we confirmed the overexpression of GPX1, SELENOS, TXNRD1 and TXNRD3 in both cell lines, and GPX4 in one cell line, as well as the downregulation of SELENOW in both cell lines (Figure S2A), overall suggesting again that these selenoproteins should play a tumor-related role in TNBC cells.