Fig. 2

Mechanisms mediating the resistance of CSCs to scores of therapy. Multiple intrinsic and extrinsic resistant mechanisms controlling CSC respond to traditional or novel therapy. In the process or after therapy, CSCs display several properties: higher degree of drug efflux activity, active DNA repair, high ROS levels, the tendency of VM; moreover, non-CSCs may reacquire CSC properties by EMT, microenvironment, autophagy and extracellular vesicles also contribute to tumor relapse