Dyatlovitskaya E V, Novikov A M, Gorkova N P, Bergelson L D
Eur J Biochem. 1976 Apr 1;63(2):357-64. doi: 10.1111/j.1432-1033.1976.tb10237.x.
The highly malignant rat hepatoma 27 was found to have increased amounts of lipid-bound sialic acid as compared with normal liver whereas in regenerating liver the lipid-bound sialic acid level was reduced. In contrast to the liver the hepatoma contained higher amounts of disialogangliosides and no trisialogangliosides, which are abundant in the liver. The main disialoganglioside of the hepatoma had no analogue among the liver gangliosides and was identified as Gal-GalNAc(AcNeu-AcNeu)-Glc-Cer (GD1b), which in other tissues is known to be a precursor of trisialogangliosides. These findings may be explained by a reduced activity of glycosyltransferases in the hepatoma and apparently do not simply reflect differences in growth rate since the ganglioside pattern of regenerating rat liver was not altered significantly in comparison with the liver. Liver and hepatoma microsomes were found to be enriched in gangliosides as compared with whole cells, liver mitochondria were slightly poorer, while the ganglioside level of hepatoma mitochondria was much higher than that of the hepatoma cells. It thus appears that the existing image of the plasma membranes as the only sites of high ganglioside concentration may not hold true for weakly differentiated hepatomas of high malignancy.
与正常肝脏相比，发现高恶性大鼠肝癌27中脂质结合唾液酸的含量增加，而在再生肝脏中脂质结合唾液酸水平降低。与肝脏相反，肝癌中含有较高量的二唾液酸神经节苷脂，且没有肝脏中丰富的三唾液酸神经节苷脂。肝癌的主要二唾液酸神经节苷脂在肝脏神经节苷脂中没有类似物，被鉴定为Gal-GalNAc(AcNeu-AcNeu)-Glc-Cer (GD1b)，在其他组织中它是三唾液酸神经节苷脂的前体。这些发现可能是由于肝癌中糖基转移酶活性降低所致，显然并不仅仅反映生长速率的差异，因为与肝脏相比，再生大鼠肝脏的神经节苷脂模式没有明显改变。与全细胞相比，发现肝脏和肝癌微粒体中神经节苷脂含量丰富，肝脏线粒体中神经节苷脂含量略低，而肝癌线粒体中的神经节苷脂水平远高于肝癌细胞。因此，对于高恶性低分化肝癌而言，现有的认为质膜是神经节苷脂高浓度唯一部位的观点可能并不成立。
