JCHAIN and breast cancer: After quality control, we obtained 70,713 single cells in breast cancer (Figure 1B and Figure S1), including 26,473 T cells (CD3D+, CD3E+), 8872 mesenchymal cells (PDGFRB+), 17,515 epithelial cells (EPCAM+, KRT18+), 5992 endothelial cells (PECAM1+), 2928 B cells (MS4A1+, CD79A+), 3064 plasma cells (JCHAIN+, MZB1+), 4627 myeloid cells (CD68+, LYZ+), and 1224 proliferating cells (MKI67+) (Figure 1B,C).