Western blot analysis of BTD and GPX3 in a blinded set of plasmas. (A, E) Western blot images of BTD and GPX3 in a blinded set of plasmas from 21 breast cancer and 21 normal healthy women. (B, F) Box-plots (left panels) and receiver operating characteristic (ROC) curves (right panels). (C) BTD levels according to breast cancer grade. (D) BTD levels according to estrogen receptor (ER) and progesterone receptor (PR) status.