Evaluation of KLK4 as a prostate cancer biomarker in blood serum, as measured by ELISA.
A, Blood serum samples of three groups of men were analyzed: men with biopsy-confirmed prostate cancer (n = 36, serum PSA > 4 ng/ml, median age 63 y.o.), men with negative biopsy (n = 22, PSA > 4 ng/ml, median age 61) and healthy men (n = 3; serum PSA < 1 ng/ml, median age 36). Horizontal lines represent median concentrations of proteins in each sample set. No statistically significant differences between three groups of samples were detected (Kruskal-Wallis test p = 0.41). B, ROC curve for prediction of prostate cancer on biopsy using KLK4 measured in blood serum (AUC = 0.59, p = 0.26).