Figure 1B and 1C showed that the CP stromal transcriptomes contained minimal signals for epithelial genes such as ACPP (prostatic acid phosphatase), AZGP1 (zinc α2-glycoprotein), KLK2/hK2, KLK3/PSA, MSMB/PSP94, and epithelial cell keratins (the cancer cell transcriptome [18], contained luminal KRT8, KRT18, KRT19 expression and not that of KRT5, KRT14, KRT17 for basal or intermediate cells [40]). This evidence concerns the gene KLK2 and cancer.