Dihydroceramide Desaturase Activity in Tumors

A. G. Kandyba¹, V. A. Kobliakov², A. M. Kozlov³, I. Yu. Nagaev⁴, V. P Shevchenko⁴, and E. V. Dyatlovitskaya^1*

¹Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, Moscow, 117997 Russia; E-mail: dyatl@ibch.ru

²Institute of Carcinogenesis, Blokhin Cancer Research Center, Russian Academy of Medical Sciences, Kashirskoe Shosse 24, Moscow, 115478 Russia

³Institute of Experimental Diagnostics and Tumor Therapy, Blokhin Cancer Research Center, Russian Academy of Medical Sciences, Kashirskoe Shosse 24, Moscow, 115478 Russia

⁴Institute of Molecular Genetics, Russian Academy of Sciences, pl. Kurchatova 2, Moscow, 123182 Russia

^* To whom correspondence should be addressed.

Received August 29, 2001; Revision received October 22, 2001

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Dihydroceramide desaturase activity in the transplantable mouse hepatoma-22, rat hepatoma-27, M1 sarcoma, and RS1 rat cholangiocellular carcinoma has been investigated. It was found that the dihydroceramide desaturase activity in mouse hepatoma-22 is lower than that in normal mouse liver. However, the activity of this enzyme in subcutaneously and intrahepatically transplanted rat hepatoma-27 is increased compared to normal value. Dihydroceramide desaturase activity in subcutaneously and intrahepatically transplanted M1 sarcoma as well as in hepatoma-27 is dependent on the tumor microenvironment. The enzyme activity in RS1 tumor was not revealed. The data indicate that dihydroceramide desaturase activity depends on the tumor type and its microenvironment.

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KEY WORDS: sphinganine, ceramide, dihydroceramide desaturase, hepatoma, tumor

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