Figure 1. Effects of FDA-approved non-cancer drugs on early events of tumor metastasis. Lysine buffers the acidic extracellular pH and increases the integrity of the extracellular matrix (ECM). Aspirin inhibits platelet activation and thrombocytosis. Doxycycline and tigecycline has been shown to inhibit mitochondrial biogenesis. Mifepristone or tigecycline suppresses cell migration and invasion.