HSP90AA1 and osteosarcoma: HSP90AA1, as an important regulator of autophagy, promoted autophagy through the PI3K/Akt/mTOR pathway, inhibited apoptosis through the c-Junction N terminal kinase (JNK)/P38 pathway, and was a critical factor in the development of osteosarcoma chemoresistance (Xiao et al. 2018).