Spontaneous senescence in malignant tumor cell lines / 肿瘤

ABSTRACT

Objective:To explore whether spontaneous sene-scence widely existed in malignant tumor cells. Methods:Sene-scence-associated beta-galactosidase (SA-β-Gal) staining kit was used to detect the activity of SA-β-Gal in ten different malignant tumor cell lines before and after serum deprivation. Results:SA-β-Gal was expressed in some cells of 10 malignant tumor cell lines during exponential growth phase without any treatment. However, the percentage of senescent cells was significantly different among them, the lowest expression was observed in HeLa cell line (0.65%), and the highest expression was seen in HepG2 cell line (3.69 %, F=13.006, P= 0.000). Furthermore, not all the SA-β-Gal positive aging cells were polyploid cells. After 24-h serum deprivation, the number of SA-β-Gal positive cells was significantly increased (P=0.001). Conclusion:These findings indicate that immortal malignant tumor cell lines could undergo spontaneous senescence but the level was different between various cell lines. Short-term serum de-privation significantly increased the percentage of aging cells indicating that serum deprivation-induced cell senescence may be a rapid, easy, and effective way for anti-tumor therapy.