RB1 and cancer: Indeed, RABL6A protein expression is dramatically increased in MPNSTs compared to patient-matched, benign neurofibromas.19 Notably, RABL6A controls many other cancer pathways besides CDK-RB1, including p53,29,32 AKT,34 and Myc.19,32,35 Therefore, we speculated it might have different effects on MPNST growth depending on the genetic context.