BMI1 and pachyonychia congenita: Interestingly, high-dose VPA in combination with gemcitabine has a synergic effect enhancing the sensitivity of PANC-1 and Patu8988 PC cell lines to gemcitabine, meanwhile low-dose of VPA potentiates migration, invasion, and promotes ROS production, activating AKT that induces STAT3/Bmi1 signaling cascade activation as well as migration and invasion of PC cells induced by gemcitabine.