Consistent with the above findings, no significant difference of AUC was observed when either miR-181a-5p or PSA was used as a parameter for diagnosis of prostate cancer (p = 0.1511 using cel-miR-40-3p as an exogenous control, p = 0.0546 using cel-miR-54-3p as an exogenous control) (Figure 3B and Figure S4B). Here, KLK3 is linked to prostate cancer.