Tumor M2 pyruvate kinase in plasma of patients with urological tumors

The M2 isoenzyme of pyruvate kinase (M2-PK) is specifically expressed in tu mor cells (TU M2-PK) and may therefore provide a tumor marker for malignanc ies. We have investigated the plasma concentrations of TU M2-PK in patients with renal cell carcinoma (RCC), transitional cell carcinoma of the bladde r (BCA), prostate cancer (PCA) and benign prostatic hyperplasia (BPH). TU M 2-PK was quantified with a commercially available enzyme-linked immunosorbe nt assay (ELISA) kit. Using this ELISA kit, plasma samples of 57 healthy in dividuals were compared to 63 patients with RCC, 36 patients with BCA, 58 p atients with PCA and 28 patients with BPH. Patients with carcinomas were su bdivided into those patients with nonmetastatic and those with metastatic d isease. Only patients with RCC (nonmetastatic and metastatic) showed signif icantly increased concentrations of TU M2-PK compared to normal individuals . In metastatic RCC, TU M2-PK levels were highest and were also significant ly enhanced compared to nonmetastatic RCC. The sensitivity for nonmetastati c RCC was 27.5% and for metastatic RCC 66.7% at the 95% reference value of the control group. In BCA, PCA and BPH, no significant differences could be detected. Our results indicate that TU M2-PK concentrations in plasma may be a potential biomarker of advanced RCC. Copyright (C) 2001 S. Karger AG, Basel.