The Hallmark signatures captured similar processes to the curated signatures, with several processes likely reflecting the change in microenvironmental composition: for example, the Hallmark epithelial-mesenchymal transition (EMT) signature correlated with the breast cancer stromal signatures (r = 0.86–0.91) and the Hallmark KRAS signaling signature correlated with the immune signature (ESTIMATE) (r = 0.76), suggesting each of these captured a relative change in the number of stromal or immune cells rather than differences between the tumor cells. Here, KRAS is linked to breast cancer.