垂体瘤转化基因(PTTG1)可抵抗UV诱导的细胞凋亡作用

垂体瘤转化基因（PTTG1）在很多肿瘤中呈高水平表达.越来越多的研究表明,PTTG1与细胞增殖、细胞转化有关.但PTTG1在凋亡中的作用仍不清楚.通过在细胞中下调和过表达PTTG1，观察PTTG1在UV照射诱导凋亡中的作用.结果发现, RNAi-介导下调HeLa细胞PTTG1表达可增加对UV诱导凋亡的敏感性，而过表达PTTG1则降低对UV诱导凋亡的敏感性.此外，UV照射能降低PTTG1蛋白的表达水平，并且表现为明显的剂量和时间关系.这些研究结果显示,PTTG1在UV照射诱导的凋亡中发挥重要的抗凋亡作用.这为研究PTTG1在肿瘤发生、发展中的作用机制提供了新的实验证据.

Pituitary Tumor Transforming Gene is a Novel Anti-apoptotic Gene in UV-induced Apoptosis

Pituitary tumor transforming gene (PTTG1) is widely detected in many tumors. Increasing evidences reveal that PTTG1 is associated with cell proliferation, cellular transformation and apoptosis. However, the functions of PTTG1 remain largely unclear, especially its role in DNA damage-induced apoptosis. We used UV irradiation to induce apoptosis in HeLa cells to examine the role of PTTG1 in UV-induced apoptosis. RNAi-mediated knockdown of PTTG1 expression in cells lead to hypersensitivity to UV-induced apoptosis , whereas over expression of PTTG1 decreased the UV-induced apoptosis, suggesting that PTTG1 acts as an anti-apoptotic factor in UV-induced apoptosis. Furthermore, similar to many other anti-apoptotic genes, the expression of PTTG1 in protein levels decreased upon UV irradiation of cells . Our results may provide important information for understanding the role of PTTG1 in UV-induced apoptosis and tumorigenesis.