KRT5 and prostate cancer: Currently, AMACR gene expression is used in prostate cancer diagnosis in combination with other biomarkers such as 34E12, CK5/6 or p63 (Amin et al., 2014) or with prostate cancer antigen 3 (Ouyang et al., 2009), as AMACR is most consistently upregulated in prostate cancer tissue (Thornburg et al., 2006).