RB1 and neoplasm: It is also known that several chromatin regulators are misregulated in RB and play a relevant role in tumor transformation following RB1 inactivation, including DNA methyltransferase (DNMT), Ubiquitin-like with PHD and ring finger domains 1 (UHRF1), and B lymphoma Mo-MLV insertion region 1 (BMI1) (Lee and Kim, 2021).