Supernumerary lactate dehydrogenase isozymes in human gliomas

Supernumerary bands in agarose gel electrophoresis of lactate dehydrogenase (LDH) were frequently observed in extracts of human gliomas. The supernumerary fractions which migrated cathodic to LDH-2 and/or cathodic to LDH-3 were designated LDH-2' and LDH-3'. These extra bands were clearly seen in certain gliomas and less distinctly in others, being more frequent in primitive or undifferentiated tumours. The extra bands seen in gliomas differ from the LDH-X of the testis, but LDH-2' seemed correspond to LDH-Z in placenta, hydatidiform mole, and choriocarcinoma. These sub-bands are interpreted as being produced by gliomas and as oncofetal enzymes.