Indeed, the KrTB-N (25w) group only expressed endogenous BMI1 (i.e., No DOX) and was treated with 4-NQO and allowed to develop visible tongue lesions for a longer period of time (25 weeks, 15 weeks after 10 weeks of 4-NQO treatment; ref. 25). Here, BMI1 is linked to oral cavity neoplasm.