恶性肿瘤细胞系自发性老化的研究

Spontaneous senescence in malignant tumor cell lines

目的:探讨恶性肿瘤细胞系是否普遍存在自发性老化。方法:应用老化相关半乳糖苷酶(senescence-associatedbeta-galactosidase,SA-β-Gal)染色法检测10种恶性肿瘤细胞系中SA-β-Gal的表达情况,以及血清饥饿后该酶的表达变化。结果:在无诱导处理且处于对数生长期的10种恶性肿瘤细胞系中,均发现有SA-β-Gal表达阳性的细胞,但不同细胞系中该酶表达阳性的老化细胞所占比率明显不同,最低的是宫颈癌HeLa细胞系(0.65%),最高的是肝癌HepG2细胞系(3.69%)(F=13.006,P=0.000);SA-β-Gal阳性表达的老化细胞不都是多倍体细胞;给予无血清培养液饥饿24 h后,老化细胞数目明显增加(P=0.001)。结论:恶性肿瘤细胞系会发生自发性老化,其程度与细胞系种类有关。短期饥饿培养会明显增加老化细胞所占的比率,提示饥饿诱发细胞老化可能是抗肿瘤治疗的又一快速、简单且有效的途径。

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.