L- and M2- pyruvate kinase expression in renal cell carcinomas and their metastases

Abstract

Using immunohistochemical and enzyme biochemical methods we investigated the expression of L- and M2-pyruvate kinase (PK) in normal renal tissue, renal cell carcinomas (RCCs; of clear cell, chromophilic cell and mixed cell type) and RCC metastases. L-PK was expressed in the proximal tubules of normal renal tissue and, to a variable extent, in 23/25 primary RCCs, in 1 RCC recurrence and in 10 RCC metastases. Staining intensity and percentage of stained tissue did not correlate with tumour grade. One renal oncocytoma and all extrarenal malignancies examined lacked L-PK immunoreactivity. M2-PK was mainly expressed in the distal tubules of the normal kidney and was found in all renal tumours as well as extrarenal malignancies. Quantitative biochemical investigations yielded a two- to seventeen-fold increase in PK activity in RCCs compared to the normal renal cortex taken from the same patient, whereas fructose-1,6-bisphosphatase and cytosolic glycerol-3-phosphate dehydrogenase activity was dramatically lower in RCCs. Otherwise, the activity of all other enzymes investigated (glucose-6-phosphate dehydrogenase, enolase and lactate dehydrogenase) was not significantly changed in the RCCs. The immunocytochemical results suggest that L-PK is a useful marker for RCC and its metastases, if acetone-fixed tissue is available. The quantitative changes of the concentration of PK and other enzymes in RCCs when compared with normal renal tissue probably reflect metabolic alterations related to tumour growth.

Expression Profiling in Progressive Stages of Fumarate-Hydratase Deficiency: The Contribution of Metabolic Changes to Tumorigenesis

“…Possible evidence for a more general extrapolation of this hypothesis is underlined by the observation in Fig. 3 that PKM2 is also found in renal tumors, especially those with extrarenal malignant metastasis (21). Confirming the potential ubiquity of this common metabolic pathway, as shown in Supplementary Fig.…”

“…6). Upregulation of HK (38,44), PFKP, ENO2 (22,23), PKM2 (21,33,42), and LDHA (ref. 17; with increased Aldoa in MEFs) coordinates the increased glycolysis as confirmed by the metabolomic studies, whereas downregulation of PCK1 (32) and G6PC retards the antagonistic effects of gluconeogenesis.…”

Tumor type M2 pyruvate kinase (TuM2‐PK) as a novel plasma tumor marker in melanoma

“…3 Moreover, TuM2-PK could be detected in the peripheral blood of cancer patients and might hereby serve as a tumor marker. [4][5][6][7] In our study, we show that TuM2-PK is overexpressed in tissue from metastatic melanoma lesions compared to healthy skin.…”

“…Frozen tissue specimen were thawed and extracted with a lysis buffer containing 10 mM Tris, 1 mM NaF and 1 mM mercaptoethanol (Merck, Darmstadt, Germany), pH 7.4 as described previously. 3 From this lysates, pyruvate kinase activities (V max ) were measured according to; 11 concentrations of TuM2-PK were quantified using a sandwich ELISA (ScheBo Biotech). For Western blotting, the tissue lysates were pre-diluted with lysis buffer to a final protein concentration of 2 lg/ll and thereafter diluted (1:2) with SDS sample buffer.…”

“…TuM2-PK molecules have been detected not only in malignant cells of different origin 2,3 but also in the peripheral blood 4-7 and stool 8 of cancer patients. For TuM2-PK quantification in the peripheral blood, plasma was shown to provide higher stability and therefore higher data reproducibility compared to serum.…”