Evaluation of the Pyruvate Kinase isoenzyme tumor (Tu M2-PK) as a tumor marker for cervical carcinoma

Various isoforms of the glycolytic enzyme pyruvate kinase are expressed in different cell types. One of these isoforms, Tu M2-PK, is over-expressed in tumor cells and released into body fluids. Plasma determination of Tu M2-PK has been shown to discriminate between benign and malignant lesions. Tu M2-PK was quantitated in the plasma of 50 patients with cervical carcinoma, 10 patients with chronic cervicitis and 10 healthy controls. The concentration of Tu M2-PK was determined by commercial kits using a sandwich enzyme linked immunosorbent assay based on two monoclonal antibodies (clone I and II) specific for Tu M2-PK. The sensitivity of the test for discrimination of malignant from non-malignant condition was 82% with a specificity of 60%. Highly significant statistical difference was found in the means of three groups (P = 0.0002). The present results indicate that Tu M2-PK can be used as a tumor marker in follow-up of patients with cervical carcinoma.