PTGS2 and colorectal cancer: The results showed that vitexin enhanced the inhibitory effect of aspirin on COX-2 expression in HT-29 cells at the protein (Figures 10A, B) and mRNA (Figure 10C) levels after 48 h treatment, suggesting that the inhibition of colorectal cancer cell proliferation by vitexin enhanced aspirin may be achieved through the inhibition of COX-2 expression.