TP53 and hepatocellular carcinoma: When HCC cells were co-transfected with ATAD2 siRNA and MKK3/6 siRNA, the additional suppression of MKK3/6 reduced the enhancement of p-p38, and also rescued cells from apoptosis (measured by c-PARP) caused by ATAD2 suppression in all four HCC cell lines, especially those with mutant p53 (Figure 5C).