Blizard Institute of Cell and Molecular Science, Barts and The London School of Medicine and Dentistry, London, UK.
Oncogene. 2010 Apr 15;29(15):2262-71. doi: 10.1038/onc.2009.497. Epub 2010 Jan 25.
Overexpression of Ras(G12V) in primary cells induces a permanent growth arrest called oncogene-induced senescence (OIS) that serves as a fail-safe mechanism against malignant transformation. We have performed a genome-wide small interfering RNA (siRNA) screen and a microRNA (miRNA) screen to identify mediators of OIS and show that siRNA-mediated knockdown of p21(Waf1/Cip1) rescues from Ras(G12V)-induced senescence in human mammary epithelial cells (HMECs). Moreover, we isolated a total of 28 miRNAs that prevented Ras(G12V)-induced growth arrest, among which all of the miR-106b family members were present. In addition, we obtained a number of hits, miR-130b, miR-302a, miR-302b, miR302c, miR-302d, miR-512-3p and miR-515-3p with seed sequences very similar to miR-106b family members. We show that overexpression of all these miRNAs rescues HMECs from Ras(G12V)-induced senescence by prevention of Ras(G12V)-induced upregulation of p21(Waf1/Cip1). Our results establish an important role for the cell cycle inhibitor p21(Waf1/Cip1) in growth control of HMECs and extend the repertoire of miRNAs that modulate the activity of this tumour suppressor.
Ras(G12V)在原代细胞中的过表达会诱导一种称为癌基因诱导的衰老（OIS）的永久性生长停滞，这是一种防止恶性转化的失效保护机制。我们进行了全基因组小干扰 RNA（siRNA）筛选和 microRNA（miRNA）筛选，以鉴定 OIS 的介质，并表明 p21(Waf1/Cip1)的 siRNA 介导的敲低可挽救人乳腺上皮细胞（HMEC）中 Ras(G12V)诱导的衰老。此外，我们总共分离出 28 种 miRNA，可防止 Ras(G12V)诱导的生长停滞，其中所有 miR-106b 家族成员都存在。此外，我们还获得了许多命中，miR-130b、miR-302a、miR-302b、miR302c、miR-302d、miR-512-3p 和 miR-515-3p，其种子序列与 miR-106b 家族成员非常相似。我们表明，所有这些 miRNA 的过表达通过防止 Ras(G12V)诱导的 p21(Waf1/Cip1)上调来挽救 HMEC 免受 Ras(G12V)诱导的衰老。我们的结果确立了细胞周期抑制剂 p21(Waf1/Cip1)在 HMEC 生长控制中的重要作用，并扩展了调节这种肿瘤抑制因子活性的 miRNA 谱。
