Although the precise mechanism was not investigated in the present study, we speculated that since the effect of APOBEC3B on the increase in mutations may be greater than the effect of NEIL3 on a decrease in mutations through its DNA glycosylase activity, the coelevated expressions of NEIL3 and APOBEC3B may lead to the observed increase in the number of somatic mutations in cancer. This evidence concerns the gene NEIL3 and cancer.