However, it has also been found that high expression of RBBP7 has a cancer suppressive effect on early breast cancer cells instead, which are more susceptible to apoptosis activated by JNK signaling pathway, as RBBP7 is targeted by tumor suppression gene WT1 to activate growth arrest- and DNA damage-inducible gene GADD45 (Li et al., 2003). This evidence concerns the gene MAPK8 and breast cancer.