Role of autophagy in drug resistance and regulation of osteosarcoma (Review)

Abstract

Osteosarcoma (OS) is a malignant tumor originating from primitive mesenchymal tissue that occurs mostly in children and adolescents. It is the most common type of malignant tumor originating from bone. The combination of chemotherapy and surgery is an important treatment strategy for OS; however, multidrug resistance frequently leads to failure of chemotherapy for OS. Autophagy is considered an important mechanism through which bone tumor cells escape apoptosis; inhibition of autophagy may significantly increase the sensitivity of tumor cells to chemotherapeutic drugs. The present review discusses the relationship between chemotherapy resistance and autophagy-related genes, the regulation of autophagy in OS, as well as drugs that inhibit protective autophagy in tumors or cause autophagic death of OS cells or increase their sensitivity to chemotherapy drugs, thereby reducing chemotherapy resistance and increasing efficacy.

Keywords: autophagy; drug regulation; drug resistance; osteosarcoma.

Figure 1

Schematic illustration of the different types of autophagy. Macroautophagy is a common autophagic pathway, mitophagy is a specific type of autophagy, which may occur in mitochondria, and chaperone-mediated autophagy is a selective type of autophagy with a unique mechanism. KFERQ is a pentapeptide motif. HSC70, heat shock cognate 71 kDa protein; LAMP, lysosomal-associated membrane protein.