Differences in Lipid Composition and Proliferative Activity of Rat Hepatoma-27 Depending on the Target Organ

V. A. Kobliakov¹, O. G. Somova², V. F. Kondalenko¹, N. M. Ostashkina³, A. G. Kandyba², T. K. Dubovaya³, and E. V. Dyatlovitskaya^2*

¹Institute of Carcinogenesis, Blokhin Cancer Research Center, Russian Academy of Medical Sciences, Kashirskoe Shosse 24, Moscow, 115478 Russia

²Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, Moscow, 117997 Russia; E-mail: dyatl@ibch.ru

³Russian State Medical University, ul. Ostrovityanova 1, Moscow, Russia

^* To whom correspondence should be addressed.

Received July 17, 2000; Revision received September 8, 2000

---

Proliferative activity and lipid composition (phospholipids and gangliosides) were studied in rat hepatoma-27 transplanted subcutaneously or intrahepatically (as models for primary and metastasizing tumors). The mitotic index of subcutaneously transplanted hepatoma far exceeded that of the intrahepatically transplanted tumor. The overall amounts of both phospholipids and gangliosides increased appreciably in the subcutaneously growing hepatoma (in contrast to the intrahepatically growing tumor) in comparison to the control hepatic tissue. The ganglioside composition in the tumors differs from that in the liver: ganglioside GD3 appears, whereas gangliosides GD1b and GT1b decrease in amount in the intrahepatic tumor compared to the control liver and disappear in the subcutaneously transplanted hepatoma. In both tumor types, the amounts of both phosphatidylethanolamine and sphingomyelin exceed the control values. Comparison of these results with previously reported data concerning the phospholipid and ganglioside composition in the regenerating rat liver indicates that the difference in the lipid composition between the subcutaneously and intrahepatically growing hepatomas-27 is due to their different proliferative status and also their microenvironment.

---

KEY WORDS: proliferation, liver, hepatoma, metastasis, phospholipids, gangliosides

---