For example, curcumin, a flavonoid from Curcuma longa, inhibits COX-2 and its downstream genes resulting in the induction of apoptosis through the regulation of AMP-activated protein kinase (AMPK) in MCF-7 breast cancer cells and HT-29 colon cancer cells (Mortezaee et al., 2019). Here, PTGS2 is linked to breast cancer.