The determination of the hSNF5 target genes and the clarification of the transcriptional mechanism of hSNF5

hSNF5靶基因的确定及hSNF5转录机制的阐明

• 批准号: 22890157
• 负责人: KUWAHARA Yasumichi
• 金额: $ 1.89万
• 依托单位: Kyoto Prefectural University of Medicine
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Research Activity Start-up
• 财政年份: 2010
• 资助国家: 日本
• 起止时间: 2010 至 2011
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-22890157/
• 关键词: ラブドイド腫瘍; hSNF5; NOXA; SWI/SNF複合体; Mcl-1; p21; p53

Malignant rhabdoid tumor(MRT), a highly aggressive cancer of young children, displays inactivation of the hSNF5 gene in primary tumors and cell lines. We have previously reported that reexpression of hSNF5 in MRT cell lines causes a G1 arrest via p21WAF1/CIP1(p21) mRNA induction. However, the mechanisms of p21 promoter activation by hSNF5 remain unclear.Because p21 is a transcriptional target of the p53 tumor suppressor gene, we determined the role of p53 in hSNF5-induced p21 activation. We reexpressed hSNF5 in the A204 and TTC642 MRT cell lines, with or without stable knockdown of p53 expression, using adenoviral vectors expressing either hSNF5 and GFP or GFP. While loss of p53 expression significantly inhibited p21 transcriptional activity induced by hSNF5 in A204 cells at 24 hours, it did not alter its activity by hSNF5 after 24 hours in the TTC642 cells. These results suggested that the up-regulation p21 transcription by hSNF5 operated through p53-dependent and. independent mechani … More sms in the A204 and TTC642 cell lines, respectively. Next, we used chromatin immunoprecipitation(ChIP) analysis of the p21 promoter to determine where hSNF5 appeared at the p21 promoter and whether its recruitment altered binding of other transcription factors or the chromatin landscape. Our results indicated that reexpressed hSNF5 binds within 1 kb of transcript start site(TSS), with maximal enrichment at the TSS in both cell lines. Furthermore, histone acetyltransferases(HATs), RNA polymerase II(RNAPII), and BRG-1 are assembled with p53 and CDK8(co-activator of p53 transcriptional program) by reexpression of hSNF5 in A204 cells. In contrast, while p53 and CDK8 occupancy did not change after hSNF5 reexpression in the TTC642 cells, HATs, RNAPII, and BRG-1 levels increased at the p21 promoter. These findings correlated with the results of p53 knock-down experiments. Furthermore, histone H3K36 tri-methylation increased downstream of the TSS in both cell lines. These results suggested hSNF5 regulates the initiation activity of the p21 promoter by either itself or p53 recruitment, resulting in the mRNA elongation.Our findings demonstrate that while induction of p21 transcription by hSNF5 in A204 cells depends on p53, it occurs independently of p53 in TTC642 cells. The lack of dependence upon p53 appears to extend to other MRT cell lines tested in our laboratory. Furthermore, our results suggest that hSNF5 may alter p21 transcriptional initiation by itself or through the recruitment of other uncharacterized transcription factors. Less

恶性胸腺肿瘤（MRT）是一种高度侵略性儿童的癌症，在原发性肿瘤和细胞系中表现出HSNF5基因的失活。我们先前已经报道了MRT细胞系中HSNF5的重新表达会通过P21WAF1/CIP1（P21）mRNA诱导引起G1停滞。但是，HSNF5启动子激活的机制尚不清楚。由于p21是p53肿瘤基因的转录靶标，因此我们确定了p53在HSNF5诱导的p21激活中的作用。我们使用表达HSNF5和GFP或GFP的腺病毒载体，在A204和TTC642 MRT细胞系中重新表达了HSNF5。虽然p53表达的损失显着抑制了HSNF5在24小时在A204细胞中诱导的p21转录活性，但在TTC642细胞中24小时后，它不会改变HSNF5的活性。这些结果表明，HSNF5的上调P21转录通过p53依赖性和。独立的机制…分别在A204和TTC642细胞系中的SMS。接下来，我们使用p21启动子的染色质免疫沉淀（CHIP）分析来确定HSNF5在p21启动子上出现的位置，以及其募集是否改变了其他转录因子的结合或染色质景观的结合。我们的结果表明，重新表达的HSNF5在1 kb的转录启动位点（TSS）内结合，在两个细胞系中的TSS处最大富集。此外，组蛋白乙酰转移酶（HATS），RNA聚合酶II（RNAPII）和BRG-1通过在A204细胞中的HSNF5重新表达与P53和CDK8（p53转录程序的共激活器）组装。相反，p53和cdk8的占用率在TTC642细胞中HSNF5重新表达后没有变化，帽子，RNAPII和BRG-1水平在p21启动子处增加。这些发现与p53敲低实验的结果相关。此外，在两种细胞系中，组蛋白H3K36三甲基化增加了TSS的下游。这些结果表明，HSNF5通过本身或p53募集来调节p21启动子的启动活性，从而导致mRNA伸长率。我们的发现表明，尽管HSNF5在A204细胞中诱导P21转录取决于p53，但它与TTC642细胞中的p53无关。缺乏对p53的依赖似乎扩展到了我们实验室测试的其他MRT细胞系。此外，我们的结果表明，HSNF5可能会自身改变P21转录计划，或者通过募集其他未表征的转录因子。较少的

项目成果

Reexpression of hSNF5 regulates the transcriptional activity of the p21 promoter through p53 dependent or independent mechanisms in malignant rhabdoid tumors

在恶性横纹肌瘤中，hSNF5 的重新表达通过 p53 依赖或独立机制调节 p21 启动子的转录活性

• 发表时间: 2011
• 作者: Kuwahara Y;Durand J
• 通讯作者: Durand J

Reexpression of hSNF5 regulates the transcriptional activity of the NOXA promoter through p53 independent mechanisms in malignant rhabdoid tumors

在恶性横纹肌瘤中，hSNF5 的重新表达通过 p53 独立机制调节 NOXA 启动子的转录活性

• 发表时间: 2011
• 作者: Kuwahara Y;Durand J;Weissman BE
• 通讯作者: Weissman BE

Sensitivity of malignant rhabdoid tumor cell lines to PD0332991 is inverserly correlated with p16 expression

恶性横纹肌瘤细胞系对 PD0332991 的敏感性与 p16 表达呈负相关

• 发表时间: 2011
• 期刊: Biochem Biophys Res Commun
• 作者: Katsumi Y;Iehara T;Miyachi M;Yagyu Y;Tsubai-Shimizu T;Kikuchi K;Tamura S;Itoh H;Kuwahara Y;Tsuchiya K;Kuroda H;Sugimoto T;Houghton PJ;Hosoi H
• 通讯作者: Hosoi H

hSNF5はp53依存性機序とp53非依存性機序でp21の転写を制御する

hSNF5 通过 p53 依赖和 p53 独立机制调节 p21 转录

• 发表时间: 2011
• 作者: 〓原康通;Bernard Weissman、細井創
• 通讯作者: Bernard Weissman、細井創

Malignant Rhabdoid Tumor(悪性ラブドイド腫瘍: MRT)の最新治療と今後の課題:COG、EUの現況をふまえて

恶性横纹肌样瘤（MRT）的最新治疗方法和未来挑战：基于COG和欧盟的现状

• 发表时间: 2012
• 作者: 〓原康通;勝見良樹、土屋邦彦、家原知子、細井創
• 通讯作者: 勝見良樹、土屋邦彦、家原知子、細井創