TP53 and osteosarcoma: TP53 is a transcription factor that stabilizes and induces cell cycle arrest after genotoxic stress to function as a tumor suppressor, however, mutated TP53 not only causes cell cycle dysregulation, but also enhances the proliferative capacity of osteosarcoma cells, the study found that in a pig model, the mutated TP53 and its circular counterpart play an important role in the occurrence and progression of osteosarcoma and various cancers 31.