To explore the relation between proliferation and necrosis further, we examined how independent proliferation signatures associated with tumor necrosis and found higher Stathmin33, Oncotype DX34 and PCNA scores35 in tumors with necrosis, supporting increased tumor cell proliferation in breast cancer with tumor necrosis (TCGA; all P < 0.001, Fig. 4A). This evidence concerns the gene PCNA and breast carcinoma.