Corrigendum: β-Sitosterol and Gemcitabine Exhibit Synergistic Anti-Pancreatic Cancer Activity by Modulating Apoptosis and Inhibiting Epithelial–Mesenchymal Transition by Deactivating Akt/GSK-3β Signaling - Cao, Zhang-qi; Wang, Xue-xi; Lu, Li; Xu, Jing-wen; Li, Xiao-bin; Zhang, Guang-ru; Ma, Zhan-jun; Shi, An-chen; Wang, Yan; Song, Yu-jun (Frontiers in Pharmacology, 2020)