Prealbumin subfractions in brain tumors--with special reference to ontogenic changes (author's transl)

Abstract

Prealbumin (PA) and its subfractions were analyzed to find their significance in the central nervous system from ontological and oncological points of view, using 7.5% polyacrylamide gel disc electrophoresis according to Ornstein51) & Davis.14) Tissues of 11 cases of normal human cerebrum, ranging from 5 or 6 months gestation to 64 years old, and 26 cases of brain tumor which included 12 gliomas, 8 meningiomas and 6 neurinomas were analyzed. Body fluids of 11 cases of brain tumor cysts, 12 ventricular cerebrospinal fluid with various neurological diseases, and 20 sera from the normal and the diseased were analyzed. 1. Tissue PA was subfractionated into five major peaks in the normal human brain, which we labeled PI through PV from the anodal side to the cathodal. In most of the brain tumors more than five peaks were subfractionated. 2. Concentration of PA subfractions changed in the developmental course in human brain. Among them, PIII and PIV changed remarkably in the fetal brain, namely, higher PIII and lower PIV levels were noted when compared to those of the adult brain. PI and PII showed no change during life. 3. Brain tumor had the same tendency as fetal brain regarding concentration of PIII and PIV subfractions. 4. PA III/IV ratios were compared as an index for showing some similarity in fetal brain and brain tumor tissues, and some tendency between them were observed. 5. PA fraction has been named as “neuronin” by Bowen et al.7)8)9)58) and as “SPR protein” by Kawakita32), and some of its subfractions have been identified, for instance, PI as S 100, PIV as 14-3-2 or antigen α, PV as a sensitive index for hypoxia or neurotubulin protein. PIII as well as PII still have not been identified. Further analysis of these proteins, immunochemically as well as electrophoretically, might answer the question of whether or not there are oncofetal proteins in the central nervous system.