Tumor marker pyruvate kinase type tumor M2 in patients suffering from diabetic nephropathy.
BACKGROUND
Compared to normal tissues all tumors investigated so far and especially those with a metastatic potential overexpress an isoenzyme of the pyruvate kinase, the pyruvate kinase type tumor M2 (TU M2-PK). Because of its monomeric structure, the TU M2-PK has no function at all.


METHODS
Using an enzyme-linked immuno sorbent assay (ELISA) developed by ScheBooTech (Wettenberg, Germany) we measured the concentration of TU M2-PK in EDTA-plasma of 12 probands with insulin-dependent diabetes mellitus and 91 patients suffering from non-insulin-dependent diabetes mellitus, both with diabetic nephropathy. Moreover we focused on the way it compares to other metabolic markers such as HbA1c, glucose and proteins.


RESULTS
Among the 12 patients afflicted by insulin-dependent diabetes mellitus 17%, and the 91 probands with non-insulin-dependent diabetes mellitus as many as 19% of the samples were raised over the cut-off of 25 U/ml EDTA-plasma. A correlation with the other investigated parameters could not be found.


CONCLUSIONS
This study shows that the TU M2-PK in EDTA-plasma of patients with diabetic nephropathy presents 38.8% "false-positive" data and thus must be questioned as a tumor marker.
Oremek
G M
GM
Central Laboratory, Hospital of the Johann Wolfgang Goethe-University, Frankfurt/Main, Germany.
Rutner
F
F
Sapoutzis
N
N
Sauer-Eppel
H
H
D015415:Biomarkers / Q000097:blood; D014408:Biomarkers, Tumor / Q000097:blood*; D001786:Blood Glucose / Q000378:metabolism; D001798:Blood Proteins / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000201:enzymology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000201:enzymology; D003928:Diabetic Nephropathies / Q000097:blood / Q000201:enzymology*; D004797:Enzyme-Linked Immunosorbent Assay; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D011770:Pyruvate Kinase / Q000097:blood*
D015415:Biomarkers; D014408:Biomarkers, Tumor; D001786:Blood Glucose; D001798:Blood Proteins; D006442:Glycated Hemoglobin; D007527:Isoenzymes; D011770:Pyruvate Kinase