Chun M, Hoffmann M K
Lymphokine Res. 1987 Summer;6(3):161-7.
Tumor necrosis factor (TNF) destroys certain tumor cells in vitro. Using the classical TNF-sensitive cell line L929 and its resistant derivative, we show here that the sensitivity of cells to TNF depends in large measure on the intracellular cAMP concentration. An experimental increase of the intra-cellular cAMP concentration can substantially enhance the sensitivity of L-cells to TNF. This increase in TNF sensitivity is seen only in TNF-sensitive cells but not in TNF-resistant cells. An increase in intracellular cAMP levels has been obtained by adding cell permeable dibutyryl cAMP to the culture medium or by culturing L929 cells in the presence of reagents which cause the elevation of intracellular cAMP concentrations.
肿瘤坏死因子（TNF）在体外可破坏某些肿瘤细胞。利用经典的对TNF敏感的细胞系L929及其抗性衍生物，我们在此表明细胞对TNF的敏感性在很大程度上取决于细胞内cAMP浓度。细胞内cAMP浓度的实验性增加可显著增强L细胞对TNF的敏感性。这种TNF敏感性的增加仅在对TNF敏感的细胞中可见，而在对TNF抗性的细胞中则未观察到。通过向培养基中添加可透过细胞的二丁酰cAMP或在能导致细胞内cAMP浓度升高的试剂存在下培养L929细胞，可实现细胞内cAMP水平的增加。
