摘要
背景与目的:许多研究表明高表达CyclinE使细胞增殖能力增加,也有研究报道CyclinE表达较低而细胞增殖并未降低,而在我们对临床肿瘤样本进行研究时发现大量低Cyclin表达(包括CyclinE)的细胞具有旺盛的增殖能力。为了解释这一现象,本研究旨在探讨MOLT-4细胞中CyclinE阈值下降后细胞进入S期的增殖状况。方法:以低浓度咖啡因处理MOLT-4细胞2h、4h,构建CyclinE阈值降低模型,采用流式细胞术分析增殖细胞核抗原(proliferationcellnuclearantigen,PCNA)、增生抗原Ki67和光裂解诱导的选择性DNA断裂链(DNAstrandbreakinductionbphotolysis,SBIP)阳性细胞数。结果:低浓度咖啡因处理MOLT-4细胞2h、4h后,CyclinE阈值明显下降,PCNA、Ki67和SBIP阳性细胞数增加,并以咖啡因处理2h时变化最为明显。结论:CyclinE阈值由高水平迅速降低后细胞增殖陡然增加,CyclinE阈值在较低水平时细胞仍然可增殖。
BACKGROUND &OBJECTIVE: Many studies showed that high expression of Cyclin E promotes cell proliferation, but contrary data was also reported that cell proliferation didnt decrease with low expression of Cyclin E. In addition, we observed that many tumor cells have strong capability of proliferation with low expression of Cyclins, including Cyclin E. This study was to analyze effect of reduced Cyclin E threshold on proliferation of acute lymphocyte leukemia cell line MOLT 4 to explain the above phenomena. METHODS: We have established the model of decreased Cyclin E threshold in MOLT 4 cells by treating cells with low concentration (5 mmol/L)of caffeine for 2, and 4 h. The positive rates of proliferation cell nuclear antigen (PCNA), Ki67, and DNA strand break induction by photolysis (SBIP) were analyzed by flow cytometry. RESULTS: MOLT 4 cells presented sharply decrease of Cyclin E threshold, and increase of positive rates of PCNA, Ki67, and SBIP after treated with caffeine, especially at 2 h point. CONCLUSIONS: Decrease of Cyclin E threshold was accompanied by increase of cell proliferation. MOLT 4 cells may remain high proliferation capability with low level of Cyclin expression.
出处
《癌症》
SCIE
CAS
CSCD
北大核心
2004年第11期1244-1248,共5页
Chinese Journal of Cancer
基金
国家自然科学基金(No.39670265
39730270
39725027)
973肿瘤计划(No.G1998051212)
卫生部临床重点学科(No.20012537)~~
