BMI1 and neoplasm: The MKK3 tumor-suppressing role depended on Bmi-1 downregulation and p38MAPK activation, as the SB203580 rescued Bmi-1 expression downregulating p16 INK4A and p15 INK4B to normal levels and suppressing the MKK3-induced cell cycle arrest in HepG2 and PLC-PRF-5 cells [43].