Larsson Ola, Scheele Camilla, Liang Zicai, Moll Jürgen, Karlsson Christina, Wahlestedt Claes
Center for Genomics and Bioinformatics and. Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
Cancer Res. 2004 Jan 15;64(2):482-9. doi: 10.1158/0008-5472.can-03-1872.
Replicative senescence limits the number of times primary cells can divide and is therefore regarded as a potential checkpoint for cancer progression. The majority of studies examining changes of gene expression upon senescence have been made with stationary senescent cells. We wanted to study the transition from normal growth to senescence in detail and identify early regulators of senescence by analyzing early changes in global gene expression, using Affymetrix microarrays. For this purpose, we used a murine epithelial senescence model, where senescence is abrogated by SV40 large T antigen and can be induced by using a temperature-sensitive form of SV40 large T antigen (SV40ts58). Comparisons were made to wild-type SV40 large T antigen-expressing cells and to cells expressing SV40ts58 large T antigen grown to confluence. After removal of genes that are similarly regulated in wild-type and temperature-sensitive SV40 large T antigen-expressing cells, 60% of the remaining genes were shared between cells arrested by inactivation of SV40 T antigen and by confluence. We identified 125 up-regulated and 39 down-regulated candidate genes/expressed sequence tags that are regulated upon SV40 T antigen inactivation and not during heat shock or confluence and classified these based on their kinetic profiles. Our study identified genes that fall into different functional clusters, such as transforming growth factor-beta-related genes and transcription factors, and included genes not identified previously as senescence associated. The genes are candidates as early regulators of the senescence checkpoint and may be potential molecular targets for novel anticancer drugs.
复制性衰老限制了原代细胞的分裂次数，因此被视为癌症进展的一个潜在检查点。大多数研究衰老过程中基因表达变化的实验都是用静止的衰老细胞进行的。我们希望详细研究从正常生长到衰老的转变，并通过使用Affymetrix微阵列分析全局基因表达的早期变化来确定衰老的早期调节因子。为此，我们使用了一种小鼠上皮衰老模型，在该模型中，衰老可被SV40大T抗原消除，并且可以通过使用温度敏感型的SV40大T抗原（SV40ts58）来诱导。将其与表达野生型SV40大T抗原的细胞以及表达SV40ts58大T抗原并生长至汇合的细胞进行比较。在去除野生型和表达温度敏感型SV40大T抗原的细胞中受到类似调节的基因后，60%的剩余基因在因SV40 T抗原失活而停滞的细胞和因汇合而停滞的细胞之间是共有的。我们鉴定出125个上调和39个下调的候选基因/表达序列标签，它们在SV40 T抗原失活时受到调节，而在热休克或汇合过程中不受调节，并根据它们的动力学特征对这些基因进行了分类。我们的研究鉴定出了属于不同功能簇的基因，如转化生长因子-β相关基因和转录因子，并且包括了以前未被鉴定为与衰老相关的基因。这些基因是衰老检查点早期调节因子的候选基因，可能是新型抗癌药物的潜在分子靶点。
