RA induced apoptosis by upregulating caspase-8, caspase-9, and caspase-3 cleavage rates, thus enhancing the Bax/Bcl-2 ratio, triggering ROS generation, and reducing the matrix metalloproteinase (MMP); therefore, a biological target of RA in osteosarcoma cells could be DJ-1 [57]. This evidence concerns the gene PARK7 and osteosarcoma.