THE BIOCHEMICAL MODIFICATION OF THE ERYTHROCYTE-MEMBRANES FROM WOMEN WITH OVARIAN-CANCER

The aim of our work was quantitative evaluation of the protein and pho spholipid fractions of mature erythrocyte membranes separated from wom en with ovarian cancer. Blood was sampled from 30 women with ovarian c ancer, aged 24-79 years, in the third stage of clinical progression of the disease. Phospholipids were separated from membranes by Muller's acidic extraction method and analysed in thin-layer two-dimensional ch romatography. On the silica gel plates nine fractions of phospholipids were separated: sphingomyelin (SPH), phosphatidylethanolamine (PE), p hosphatidlyserine (PS), phosphatidylcholine (PC), lysophosphatidylchol ine (LPC), phosphatidic acid (PA), phosphatidylinositol (Ptd Ins), pho sphatidylinositol-4-phosphate (Ptd Ins-4-P), phosphatidylinositol-4,5- diphosphate (Ptd Ins-4,5-P2). The activity of phospholipase C in eryth rocyte membranes was determined by Akhrem's spectrophotometric method. Membrane proteins were separated by polyacrylamide gel electrophoresi s, SDS-PAGE. It was shown that PS, SPH, LPC and PA fractions were sign ificantly diminished. The concentration of Ptd Ins-4-P and Ptd Ins-4,5 -P2 was significantly increased with simultaneous reduction in Ptd Ins level. The inhibition of phospholipase C reached 80%. The quantitativ e protein evaluation showed a statistically significant decrease in sp ectrin and a significant increase in 4.1 protein. The quantitative cha nges, observed in phospholipid and protein fractions, led to the restr ucturing of the erythrocyte membrane cytoskeleton, which may be connec ted to increased susceptibility to haemolysis of red blood cells.