Changes in ganglioside contents, plasma sialic acid and cAMP levels in experimental hepatoma in mice

The present study was designed to assess whether changes in glycolipids and cyclic AMP contents might serve as markers for the diagnosis of malignancy in the liver. The experimental model was a transplantable murine hepatoma. Experimental mice were divided into three groups: (1) a therapeutic group, which had been transplanted with hepatoma and treated with the antimetabol ism drug 5-flurouracil (0.2 mg/day i.p.), (2) a control group, which had be en transplanted with hepatoma and treated with 0.2 ml 0.9% NaCl/day and (3) a normal group of mice. The ganglioside and cAMP contents in the hepatoma tissue, plasma cAMP, total- and lipid-bound sialic acid levels and red bloo d cell membrane sialic acid levels were determined. Results showed that the ganglioside content, total and lipid-bound sialic acid levels in the contr ol group were significantly higher than those in the livers of normal mice (p < 0.01) while these respective values in the therapeutic group were sign ificantly lower than those in the control group (p < 0.01). The cAMP levels of tumor tissues and plasma in the control group were lower than those in normal mice. No significant difference in red blood cell membrane sialic ac id content was observed between the therapeutic and control groups though l evels for both were higher than those in normal mice. These results indicat e that ganglioside content and sialic acid levels in hepatoma tissues were significantly elevated, and cAMP levels in hepatoma tissues were significan tly decreased during proliferation and abnormal differentiation.