RARA and cancer: The therapeutic espectrum of berberine also involved the downregulation of Snail, Slug and zinc finger E-box binding homeobox 1 (Zeb1) as well as the regulation of PI3K/Akt and retinoic acid receptor alpha and beta (RARα/RARβ) signaling, acting on the proliferation capacity of various cancer cells (Liu et al., 2015; Kou et al., 2016).