Exposure to low dose of ionizing radiation was found to suppress cancer cell proliferation via suppressing p38 kinase in MCF-7 human breast cancer cells [103], inhibiting JNK as well as ERK phosphorylation [87], and down-regulating NF-κB through suppressing TNFα-induced degradation of inhibitor of kappa B (IκB) protein and release of p65 subunit to the nucleus, reducing NF-κB activity [104]. This evidence concerns the gene MAPK8 and breast cancer.