DNA聚合酶α的活性与癌细胞发生和发展的关系

The Relation between Activity of DNA Polymerase α and Occurrence or Development of Cancerous Cells

测定了７７１２系正常小鼠的胸腺、肝、脾和接种艾氏腹水癌细胞５ｄ、７ｄ、９ｄ后小鼠的胸腺、脾和腹水细胞的ＤＮＡ聚合酶α的比活性。结果表明：接种不同天数的腹水癌细胞内ＤＮＡ聚合酶α的比活性均比各类正常细胞者（包括正常鼠和癌鼠）高，差异有高度显著性或显著性。表现出ＤＮＡ聚合酶α活性与某种癌细胞的发生发展呈正相关趋势。

Cells were collected from thymus, liver and spleen of mormal 7712 mice, and were collected from thymus, spleen and ascites of mice with Ehrlich ascites carcinoma. Those cells were homogenized by ultrasonication, and were centrifugalized under 37 000×g. Then the activity of DNA polymerase α in the supernatants were determined with tritiated deoxyadenosine triphosphate(3￣H-dATP)i. e, radioisotopic enzyme assay, and amount of proteins in it was determined with ultraviolet absorption spectrometry. The result is that the specific activity of DNA polymerase α in ascites carcinoma cells that were inoculated different from days is much higher than that in all normal cells. It shows that the activity of DNA polymerase α is directly proportional to occurrence or development of cancerous cells.Perhaps, there existed to be a DNA polymerase in the cancerous cells that are different from which in the normal cells.