The nature of soluble factors from liver and hepatomas which inhibit [3 H]thymidine incorporation into DNA was studied in Novikoff hepatoma cells. The decreased activity in hepatoma preparations was due to loss of a high-molecular-weight heat-labile factor. Although this factor cochromatographed with arginase activity on Sephadex G-150, it does not appear to result from this activity as judged by the failure of arginine to prevent the inhibitory effect on [3 H]thymidine incorporation. Both liver and hepatomas contained a heat-stable factor with inhibitory activity. Studies with ethanol-soluble material suggested that the action was not solely attributable to the presence of unlabeled thymidine, since the apparent molecular weight was too high and since the factors) inhibited [3 H]leucine incorporation into protein in addition to inhibiting [3 H]thymidine incorporation in DNA.
|Original language||English (US)|
|Number of pages||6|
|State||Published - May 1 1979|
All Science Journal Classification (ASJC) codes
- Cancer Research