ERBB2 and breast cancer: To reveal how Scissor+ tumor cells cause the poor overall survival in breast cancer patients, we further identified 200 upregulated and 317 downregulated DEGs in Scissor+ tumor cells and other tumor cells (Figure 2D and Table S2), finding that these top downregulated genes in Scissor+ tumor cells were IFI6, BTG2, CD74, SLC39A6, and SAA1, etc., while the top upregulated genes were KRT81, SCGB1B2P, GRB7, MIEN1, and ERBB2 (also called HER2), etc. (Figure 2D).