Extended Data Figure 8: Overexpression of SERPINE2 and SLPI in human breast cancer cell lines.

a, MDA-MB-231 cells infected with an empty overexpression vector plated on Matrigel (top) and MDA-MB-231 cells overexpressing SERPINE2 (NM_0016216) plated on Matrigel (bottom). b, Full quantification of tubular structures in basal cell lines MDA-MB-231 and MDA-MB-436 when infected with an empty overexpression vector or when infected with vectors for overexpressing SERPINE2 or SLPI (P < 0.05, Friedman test, for SERPINE2 isoform NM_0016216 and SLPI, n = 4 fields). c, Quantification of CD31⁻/PAS⁺ channels in MDA-MB-436-derived primary tumours cells that have been infected with an empty retroviral vector or vectors for overexpression of SERPINE2 or SLPI (P < 0.002, Wilcoxon rank-sum, for SERPINE2 isoform NM_001136528 and SLPI, n = 20 fields for empty, SERPINE2 NM_001136528 and NM_0016216 and n = 25 fields for SLPI). d, The percentage of lung metastatic burden after orthotopic injection of MDA-MB-231 cells that have been infected with an empty retroviral vector or vectors for overexpression of SERPINE2 or SLPI (P < 0.05, Wilcoxon rank-sum, n = 9 mice). e, Quantification of the number of lung metastatic nodules after orthotopic injection of MDA-MB-436 cells that have been infected with an empty retroviral vector or vectors for overexpression of SERPINE2 or SLPI (Wilcoxon rank-sum P < 0.05 for SERPINE2 isoform NM_001136528 and SLPI, n = 9 mice). f, Sub-clonal analysis of MDA-MB-436 cells that have been infected with an empty retroviral vector or vectors for overexpression of SERPINE2 or SLPI. Each cell line was infected with a barcode library and then the number of clones were quantified in the primary tumour, cardiovascular CTCs and lung metastatic cells (P < 0.02, Wilcoxon rank-sum, for SERPINE2 isoform NM_001136528 and SLPI in CTCs and lung metastasis, n = 5 mice). For all box plots, the edges of the box are the twenty-fifth and seventy-fifth percentiles. The error bars extend to the values q3 + w(q3 − q1) and q1 − w(q3 − q1), where w is 1.5 and q1 and q3 are the twenty-fifth and seventy-fifth percentiles.