They also play a part in multiple diseases such as, the human immunodeficiency virus protease in acquired immunodeficiency syndrome [7], peptidyl dipeptidase A (ACE) in cardiovascular diseases [8], cathepsin K in osteoporosis [9,10], β-site APP-cleaving enzyme in Alzheimer’s disease [11,12], serine aminopeptidases in type 2 diabetes [13], and various proteases in cancers [14,15]. This evidence concerns the gene ACE and cancer.