Last, transcriptional analysis of PAM50 (Prediction Analysis of Microarray 50)–defined molecular subtypes (26) of clinical breast cancer tissues from 840 patients (27) indicates that, compared with normal tissue, S100A8/A9 is overexpressed in basal-like and Her2-enriched subtypes that have poor clinical outcomes and underexpressed in the two luminal subtypes (Fig. 1E). Here, S100A8 is linked to breast cancer.