MMP9 and breast cancer: In ovarian cancer, BC, LC, and colon cancer, stress‐induced β2‐AR activation upregulates vascular endothelial growth factor (VEGF), MMP2, and MMP9 via β‐AR/cAMP/PKA signaling (targeting CREB, NF‐κB, and AP‐1), promoting angiogenesis and migration [175, 182].