A novel gamma-glutamyl transpeptidase in renal carcinoma in comparison with normal kidney enzyme

A novel gamma-glutamyl transpeptidase was found in a renal carcinoma tissue. This enzyme electrophoresed more quickly than that of normal kidney, but more slowly than normal liver enzyme. Their Rf values are 0.46, 0.33, and 0.52 for the renal carcinoma, normal kidney and normal liver enzyme, respectively. After treatment of the renal carcinoma and normal kidney enzyme with neuraminidase, the renal carcinoma gamma-glutamyl transpeptidase still electrophoresed slightly faster than that of normal kidney. The catalytic properties of the renal carcinoma gamma-glutamyl transpeptidase were almost the same as those of normal kidney except for molecular weight; the molecular weight for the renal carcinoma was estimated to be about 130 000, while that of normal kidney was about 90 000. These results may mean that the enzyme of the renal carcinoma is different from that of normal kidney in chemical constituents other than sialic acid. Of 10 patients with renal carcinoma examined electrophoretically, 5 posessed this novel enzyme in their renal carcinoma tissues.