For example, Liu et al., (2015) discovered that Rh2inhibitedthe proliferation, decreased HDAC activity and promoted histone acetylation in K562 cells, which further suggested its role as a HDAC inhibitor.Rg3 also exerted antiproliferative activity in melanoma by reducing the activity of HDACs and increasing p53 acetylation in both experimental and clinical research (Sun et al., 2019). Here, HDAC9 is linked to melanoma.