SERPINB2 and neoplasm: Having observed the regulation of plasmin activity and tPA/PLAT, uPA/PLAU, and PAI‐2/SERPINB2 by ALDH1A3 in cultured TNBC cells along with positive gene expression correlations between ALDH1A3 and PLAT and PLAU in TNBC patient tumours (Figs 1, 2, 3), we wondered if these correlations would be observed at the protein level in tumours.