Molecular Cytogenetics of Solid Tumors

实体瘤的分子细胞遗传学

• 批准号: 8552645
• 负责人: NICOLAE POPESCU
• 金额: $ 123.44万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8552645
• 关键词: 8p21; Accounting; Adherens Junction; Antineoplastic Agents; Area; Binding; Cancer Prognosis; Cell membrane; Cells; Chromosomes; Chromosomes, Human, Pair 8; Clinical Trials; Complex; Cytoskeleton; DLC1 gene; DLEC1 gene; DNA Methyltransferase; DNA Modification Methylases; DNA Structure; DNA copy number; Development; Diagnosis; Disease; Down-Regulation; E-Cadherin; Epigenetic Process; Exposure to; Future; Gene Mutation; Genes; Genomics; Goals; Guanosine Triphosphate; Hepatocyte; Heterogeneity; Histone Deacetylase Inhibitor; Histone Deacetylation; Human; Hypermethylation; Immunofluorescence Immunologic; Intervention; Link; MYC gene; Malignant - descriptor; Malignant Epithelial Cell; Malignant Neoplasms; Malignant neoplasm of liver; Malignant neoplasm of prostate; Mediating; Metastasis Suppressor Genes; Molecular; Molecular Biology; Molecular Cytogenetics; Mus; Nude Mice; Oncogene Proteins; Oncogenes; Pathogenesis; Pathway interactions; Pattern; Primary carcinoma of the liver cells; Prostate; Proteins; Protocols documentation; Recurrence; Regimen; Research; Rho-associated kinase; Role; Screening procedure; Signal Pathway; Signal Transduction; Site; Solid Neoplasm; Staining method; Stains; Structure; Therapeutic; Therapeutic Intervention; Tumor Suppressor Genes; Vorinostat; Work; Yeasts; alpha catenin; arm; cancer cell; cancer therapy; carcinogenesis; design; human DLC1 protein; insight; interest; kinase inhibitor; knock-down; metastatic process; novel; novel therapeutics; preclinical evaluation; programs; promoter; research study; restoration; rho; small molecule; tumor; tumor growth; tumor progression; yeast two hybrid system

Deleted in liver cancer-1 (DLC-1) has been recognized as a major tumor suppressor gene (TSG) and is increasingly considered as a metastasis suppressor gene (MSG) in multiple cancers. Over the past few years our work focused primarily in protein interaction, a new area of our research program designed to gain insights into the function of Deleted in liver cancer-1 gene. A yeast-two hybrid screening identified several binding partners of Deleted in liver cancer-1 that were confirmed in human cells and thus enabling us to examine the consequences of their interactions on Deleted in liver cancer-1 function. Our previous studies underlined the importance to Deleted in liver cancer-1 interaction with proteins other than Rho GTP ases and their therapeutic implication. In the last year a novel protein interacting with Deleted in liver cancer-1 was identified, potential therapeutic applications related to DLC1 antitumor effects combined with tumor promoting action of MYC oncogene in human hepatocellular carcinoma (HCC) have been proposed and a preclinical evaluation showing that the robust antitumor effect of a potent histone deacetylase (HDAC) inhibitor and restoration of Deleted in liver cancer-1 expression in prostate cancer cells may be therapeutically beneficial in this form of cancer. Deleted in liver cancer-1 protein interaction with alpha-catenin was demonstrated, the binding motifs of both proteins were identified and by immunofluorescence staining the two binding partners were colocalized together with adherens junctions (AJs). DLC-1-alpha-catenin complex reduced Rho GTP level at plasma membrane, increased E-cadherin expression that resulted in disruption of cytoskeleton organization and stabilization of AJs. Functional relevance was assessed by knocking down alpha-catenin in DLC-1-positive cells, an experiment that had multiple effects underlining an important role for Deleted in liver cancer-1 in AJs. This interaction is highly relevant to the metastatic process as the observed functions resulted in a strong oncosuppressive effect of DLC1 on metastatic prostate carcinoma cells. Inactivation of TSGs is a major contributing alteration in the initiation or progression of cancer. Down regulation and inactivation of Deleted in liver cancer-1 is mediated predominantly by promoter hypermethylation and histone deacetylation. Because DNA methyltransferase and HDAC inhibitors can induce the restoration of Deleted in liver cancer-1 expression, the Deleted in liver cancer-1 protein may also represent a potential target for novel therapies. Given the considerable interest and progress in epigenetic therapy, a number of promising antineoplastic agents, particularly HDAC inhibitors, have been developed and used successfully in clinical trials. Both Deleted in liver cancer-1 and HDAC inhibitors exert antineoplastic functions, and their combined action could be exploited for a more effective cancer therapy. To evaluate the potential benefits of this approach, we examined the antineoplastic effects of DLC1-mediated transduction and exposure to suberoylanilide hydroxamic acid (SAHA), a powerful HDAC inhibitor, in prostate cancer cells. This combination regimen almost completely inhibited the tumors growth in nude mice thus validating this protocol as a potentially new therapeutic option in prostate cancer. Despite heterogeneity of genomic alterations in Hepatocellular Carcinoma, certain chromosomes or chromosomal sites are more commonly deleted or amplified, which results in deregulation of critical genes that, ultimately, may trigger malignant transformation of normal hepatocytes. Among the best example is the pattern of genomic alterations of chromosome 8 in Hepatocellular Carcinoma. This chromosome elicits recurrent of DNA copy number loss on the short arm (8p21) and gain on the long arm (8q34). These sites carry the loci of the Deleted in liver cancer-1 (TSG) and MYC oncogene. Overwhelming evidence accumulated in recent years demonstrates that DLC1 and MYC gene are involved pathogenesis of murine and human Hepatocellular Carcinoma. The opposite effects DLC1 and MYC in initiation and progression of Hepatocellular Carcinoma suggests that therapeutics simultaneously targeting signaling pathways governing the functions of both genes could be beneficial in the treatment of Hepatocellular Carcinoma. The inhibition of RhoA pathway and Rho kinase, a downstream effector of Rho, tops the options for therapeutic interventions. Currently, a major effort is underway to develop small molecule Rho kinase inhibitors to treat various disorders, including Hepatocellular Carcinoma. On the other hand, future pharmacologic interventions targeting MYC should be guided by a new strategy that takes into account the differential MYC roles of either tumor promoting or tumor suppressing, depending on its level of expression, and also should consider modulation of the two opposite functions of MYC oncoprotein. However, quarfloxin CX-3453, which targets MYC expression through a four-stranded DNA structure that reached clinical trials for other cancers, has the potential to be effective in therapy for liver cancer.

肝癌删除基因 1 (DLC-1) 已被认为是主要肿瘤抑制基因 (TSG)，并且越来越多地被认为是多种癌症中的转移抑制基因 (MSG)。在过去的几年里，我们的工作主要集中在蛋白质相互作用上，这是我们研究计划的一个新领域，旨在深入了解肝癌-1 基因中删除的功能。酵母-两种杂交筛选鉴定了肝癌-1中删除的几个结合配偶体，这些结合配偶体在人类细胞中得到了证实，从而使我们能够检查它们相互作用对肝癌中删除-1功能的影响。我们之前的研究强调了肝癌中Deleted-1与Rho GTP酶以外的蛋白质相互作用的重要性及其治疗意义。去年，在肝癌-1中发现了一种与Deleted相互作用的新蛋白，提出了与DLC1抗肿瘤作用结合MYC癌基因在人肝细胞癌（HCC）中的肿瘤促进作用相关的潜在治疗应用，并且临床前评估表明，有效的组蛋白脱乙酰酶（HDAC）抑制剂具有强大的抗肿瘤作用，并且可以恢复 前列腺癌细胞中肝癌-1表达的删除可能对这种形式的癌症有治疗作用。证明了肝癌删除蛋白 1 与 α-连环蛋白的相互作用，鉴定了两种蛋白的结合基序，并通过免疫荧光染色将两个结合配偶体与粘附连接 (AJ) 共定位在一起。 DLC-1-α-连环蛋白复合物降低质膜上的 Rho GTP 水平，增加 E-钙粘蛋白表达，导致细胞骨架组织破坏和 AJ 稳定。通过敲低 DLC-1 阳性细胞中的 α-连环蛋白来评估功能相关性，该实验具有多种效应，强调了删除在 AJ 中肝癌-1 中的重要作用。这种相互作用与转移过程高度相关，因为观察到的功能导致 DLC1 对转移性前列腺癌细胞产生强烈的肿瘤抑制作用。 TSG 失活是癌症发生或进展的一个主要改变。肝癌中Deleted-1的下调和失活主要是由启动子高甲基化和组蛋白脱乙酰化介导的。由于DNA甲基转移酶和HDAC抑制剂可以诱导肝癌Deleted-1表达的恢复，肝癌Deleted-1蛋白也可能代表新疗法的潜在靶点。鉴于表观遗传治疗的巨大兴趣和进展，许多有前途的抗肿瘤药物，特别是 HDAC 抑制剂，已被开发出来并在临床试验中成功使用。肝癌中的Deleted-1和HDAC抑制剂均发挥抗肿瘤功能，它们的联合作用可用于更有效的癌症治疗。为了评估这种方法的潜在益处，我们检查了 DLC1 介导的转导和暴露于辛二酰苯胺异羟肟酸 (SAHA)（一种强大的 HDAC 抑制剂）在前列腺癌细胞中的抗肿瘤作用。这种联合方案几乎完全抑制了裸鼠的肿瘤生长，从而验证了该方案作为前列腺癌的潜在新治疗选择。尽管肝细胞癌中基因组改变存在异质性，但某些染色体或染色体位点更常见地被删除或扩增，这导致关键基因的失调，最终可能引发正常肝细胞的恶性转化。最好的例子就是肝细胞癌中 8 号染色体的基因组改变模式。该染色体引起短臂 (8p21) 上 DNA 拷贝数的反复丢失和长臂 (8q34) 上 DNA 拷贝数的增加。这些位点携带肝癌删除基因 1 (TSG) 和 MYC 癌基因的位点。近年来积累的大量证据表明DLC1和MYC基因参与小鼠和人类肝癌的发病机制。 DLC1 和 MYC 在肝细胞癌的发生和进展中的相反作用表明，同时针对控制这两个基因功能的信号通路的治疗可能有益于肝细胞癌的治疗。对 RhoA 通路和 Rho 激酶（Rho 下游效应器）的抑制是治疗干预的首要选择。目前，人们正在大力开发小分子 Rho 激酶抑制剂来治疗各种疾病，包括肝细胞癌。另一方面，未来针对 MYC 的药物干预应以新策略为指导，该策略根据 MYC 的表达水平，考虑到肿瘤促进或肿瘤抑制的不同 MYC 作用，并且还应考虑对 MYC 癌蛋白的两种相反功能的调节。然而，quarfloxin CX-3453通过四链DNA结构靶向MYC表达，该结构已进入其他癌症的临床试验，有可能有效治疗肝癌。

项目成果

DLC1 interaction with S100A10 mediates inhibition of in vitro cell invasion and tumorigenicity of lung cancer cells through a RhoGAP-independent mechanism.

• DOI: 10.1158/0008-5472.can-10-2158
• 发表时间: 2011-04-15
• 期刊: Cancer research
• 影响因子: 11.2
• 作者: Yang X;Popescu NC;Zimonjic DB
• 通讯作者: Zimonjic DB

DLC1 tumor suppressor gene inhibits migration and invasion of multiple myeloma cells through RhoA GTPase pathway.

• DOI: 10.1038/leu.2008.285
• 发表时间: 2009-02
• 期刊: Leukemia
• 影响因子: 11.4

Preclinical evaluation of combined antineoplastic effect of DLC1 tumor suppressor protein and suberoylanilide hydroxamic acid on prostate cancer cells.

• DOI: 10.1016/j.bbrc.2012.02.158
• 发表时间: 2012-04-06
• 期刊: Biochemical and biophysical research communications
• 影响因子: 3.1
• 作者: Zhou X;Yang XY;Popescu NC
• 通讯作者: Popescu NC

Recurrent and nonrandom DNA copy number and chromosome alterations in Myc transgenic mouse model for hepatocellular carcinogenesis: implications for human disease.

Myc 转基因小鼠肝细胞癌变模型中的周期性和非随机 DNA 拷贝数和染色体改变：对人类疾病的影响。

• DOI: 10.1016/j.cancergencyto.2008.12.014
• 发表时间: 2009
• 期刊: Cancer genetics and cytogenetics
• 作者: Zimonjic,DrazenB;Ullmannova-Benson,Veronika;Factor,ValentinaM;Thorgeirsson,SnorriS;Popescu,NicholasC
• 通讯作者: Popescu,NicholasC