CCNA2 and colorectal cancer: According to Hsu et al. [29], methanol extracts of G. lucidum and G. tsugae inhibit the growth of colorectal cancer cells within 72 hrs by downregulating cyclin A and B1 and upregulating p21 and p27, thereby arresting the cell cycle in G2/M, and thus they are able to suppress tumor growth, induce cell death, and inhibit cell proliferation in human colorectal cancer cells in vivo.