Furthermore, the association of resveratrol and a grape seed extract (with a total phenolic content > 85% expressed as gallic acid equivalents, rich in catechin/epicatechin monomers and their oligomers) suppressed the sphere-formation ability of colorectal cancer stem cells (in vitro), down-regulated Wnt pathway proteins (pGSK3β, cyclin D1, c-Myc, β-catenin), increased the Bax/Bcl-2 protein ratio, increased p53 (the genome guardian), and decreased COX-2 activity [176]. Here, TP53 is linked to colorectal cancer.