BMI1 and sarcoma: As intrinsic regulatory factors, we included cell cycle regulators (such as BMI1, MYC protoncogene (cMyc), TP53 together with cyclin-dependent kinases inhibitors (CDKN) and cyclins), proliferative pathways involving phosphoinositide 3-kinase (PI3K) and rat sarcoma (RAS), regulators of ROS, regulators of apoptosis and all potential cross-regulation among them.