MMP9 and breast cancer: We further demonstrated that critical proinflammatory factors (interleukin-17 (IL-17), IL-6, matrix metallopeptidase-9 (MMP-9), cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), and tumor necrosis factor-alpha (TNF-α)) triggered by AA serve as chemoattractants for recruitment, retention, and proliferation of BC cells in the bones and lungs [8,9].