Epidermal growth factor elevates the activity levels of glycolipid sulfotransferases in renal-cell-carcinoma cells.
Accumulation of sulfoglycolipids associated with markedly elevated levels of glycolipid-sulfotransferase activity was previously demonstrated in human renal-cell-carcinoma cells. To elucidate the regulatory mechanisms of sulfoglycolipid metabolism in renal-cell carcinoma, effects of various growth factors on the sulfotransferase-activity levels were investigated using a human renal-cell-carcinoma cell line, SMKT-R3. Exogenous epidermal growth factor (EGF) significantly increased the activity levels of the sulfotransferases in a dose-dependent manner, but did not change that of arylsulfatase A, which hydrolyzes sulfoglycolipids. Furthermore, metabolic labeling with 35S-sulfate revealed that the addition of EGF to the culture medium of the cells resulted in an increment of sulfoglycolipid synthesis. The expression of the EGF receptor on SMKT-R3 cells was demonstrated by affinity cross-linking with 125I-EGF. These observations suggest that EGF can regulate sulfotransferase-activity levels in renal-cell-carcinoma cells, and function as one of the regulatory factors of sulfoglycolipid synthesis in these carcinoma cells.
Kobayashi
T
T
Biochemistry Laboratory, Hokkaido University School of Medicine, Sapporo, Japan.
Honke
K
K
Gasa
S
S
Kato
N
N
Miyazaki
T
T
Makita
A
A
D002292:Carcinoma, Renal Cell / Q000737:chemistry / Q000201:enzymology*; D002553:Cerebroside-Sulfatase / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D066246:ErbB Receptors / Q000032:analysis; D006017:Glycolipids / Q000378:metabolism*; D006801:Humans; D007680:Kidney Neoplasms / Q000737:chemistry / Q000201:enzymology*; D015238:Sulfotransferases; D013466:Sulfurtransferases / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D006017:Glycolipids; C011117:sulfoglycolipids; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D013466:Sulfurtransferases; D015238:Sulfotransferases; C020556:galactosylceramide sulfotransferase; D002553:Cerebroside-Sulfatase