中文摘要：

目的研究硫氧还蛋白1（thioredoxin-1，Trx-1）对细胞周期的影响。方法用维生素C刺激乳腺癌细胞MCF-7，或者用pcDNA-Trx转染MCF-7使细胞中的Trx-1表达升高，另外在细胞培养液中加入不同浓度的Trx-1；用流式细胞仪检测细胞中进入S期细胞的比例。结果维生素C的刺激使细胞内Trx-1表达上升，更多的细胞进入到S期。转染pcDNA-Trx的细胞Trx-1的表达上升，进入S期的细胞比例明显增加。将Trx-1蛋白加入到培养液中后，进入X期的细胞比例明显地随Trx-1浓度提高而升高。结论无论在细胞外还是细胞内，Trx-1水平的上升均会促使细胞进入S期。

英文摘要：

Objective To study the effects of thioredoxin-1 （Trx-1） on cell cycle. Methods The cell cycle was detected by fluorescent intensity after the Trx-1 was enhanced in breast cancer MCF-7 cells stimulated with Vitamin C （Vc） or transfected with pcDNA-Trx. Meanwhile, Trx-1 protein with different concentrations was added into the culture medium. The percentage of cells in S phase was detected by flow cytometry. Results In the breast cancer MCF-7 cells stimulated with Vc or transfected with pcDNA-Trx, the expression of Trx-1 was up-regulated and more cells entered into the S phase. The percentage of MCF- 7 cells in S phase was significantly increased with the increase of Trx-1 concentration after Trx-1 protein was added into the culture medium. Conclusion The up-regulation of Trx-1 can promote the entry of MCF-7 cells into S phase both in vivo and in vitro.