BMI1 was able to suppress the ability of oral CSCs to form cell spheres in vitro, and a BMI1 inhibitor could arrest the progression of xenograft tumours in association with a reduced proportion of CSCs.156 All these results suggest that strategies targeting CSC self-renewal, such as BMI1 inhibition, have great potential to be combined with radiotherapy in oral cancer for better prognosis. Here, BMI1 is linked to lip and oral cavity carcinoma.