The analysis of cell line and tumour datasets showing that A3B gene expression is upregulated in malignant versus normal tissues and epithelial cell lines have shown correlations between A3B expression and the presence of certain somatic mutations, particularly in TP53 [3,142] and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) (figure 3) [143]. Here, APOBEC3B is linked to neoplasm.