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.

肝癌缺失基因-1(DLC-1)已被认为是一种主要的肿瘤抑制基因(TSG)，并日益被认为是多种肿瘤中的转移抑制基因(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方面，这是我们研究计划的一个新领域，旨在深入了解肝癌-1基因缺失的功能。酵母双杂交筛选确定了几个在人类细胞中证实的肝癌中缺失的结合伙伴，从而使我们能够检查它们相互作用对肝癌中缺失功能的影响。我们以前的研究强调了在肝癌-1与Rho GTP酶以外的蛋白质相互作用中缺失的重要性及其治疗意义。在过去的一年里，一种新的与肝癌中缺失的蛋白相互作用的蛋白质被发现，与DLC1的抗肿瘤作用和myc癌基因在人肝细胞癌(HCC)中的促癌作用相关的潜在治疗应用已被提出，临床前评估表明，有效的组蛋白脱乙酰酶(HDAC)抑制剂的强大抗肿瘤作用和恢复在前列腺癌细胞中肝癌-1的缺失表达可能在治疗上有益于这种形式的癌症。证实了肝癌中缺失的蛋白-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这两个结合伙伴与黏附连接(AJs)共同定位。DLC-1-α-连环蛋白复合体降低质膜Rho GTP水平，增加E-钙粘附素的表达，从而破坏细胞骨架组织，稳定AJs。通过下调DLC-1阳性细胞中的α-连环蛋白来评估功能相关性，这一实验具有多种效果，强调了缺失在AJ中的肝癌-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了DLC1对转移性前列腺癌细胞的强烈抑制作用。TSGs的失活是癌症发生和发展的一个重要因素。肝癌中缺失基因的下调和失活主要由启动子高甲基化和组蛋白去乙酰化介导。由于DNA甲基转移酶和HDAC抑制剂可以诱导缺失的肝癌-1蛋白的表达恢复，因此，缺失的肝癌-1蛋白也可能是新疗法的潜在靶点。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，已经被开发并成功地用于临床试验。在肝癌中缺失的1和HDAC抑制剂都具有抗肿瘤功能，它们的联合作用可能被用于更有效的癌症治疗。为了评估这种方法的潜在益处，我们研究了DLC1介导的转导和暴露于强力HDAC抑制剂Suberoylanilde异羟肟酸(SAHA)对前列腺癌细胞的抗肿瘤作用。这种联合方案几乎完全抑制了裸鼠体内的肿瘤生长，从而验证了该方案作为前列腺癌潜在的新治疗方案的有效性。尽管肝细胞癌的基因组改变具有异质性，但某些染色体或染色体位置更常见地被缺失或扩增，这导致关键基因的失控，最终可能引发正常肝细胞的恶性转化。其中最好的例子是肝细胞癌中8号染色体的基因组改变模式。该染色体在短臂(8p21)引起DNA拷贝数丢失，在长臂(8q34)引起DNA拷贝数增加。这些位点携带肝癌-1(TSG)和MYC癌基因缺失的基因。近年来积累的大量证据表明，DLC1和MYC基因参与了小鼠和人肝细胞癌的发病机制。DLC1和MYC在肝细胞癌发生发展中的相反作用表明，同时靶向调控这两个基因功能的信号通路的治疗方法在肝细胞癌的治疗中是有益的。抑制RhoA途径和Rho的下游效应因子Rho激酶是治疗干预的首选选择。目前，正在进行一项重大努力，开发小分子Rho激酶抑制剂来治疗包括肝细胞癌在内的各种疾病。另一方面，未来针对MYC的药物干预应以一种新的策略为指导，根据MYC的表达水平，考虑MYC促进肿瘤或抑制肿瘤的不同作用，并考虑对MYC癌蛋白两种相反功能的调节。然而，通过四链DNA结构靶向MYC表达的四氟菌素CX-3453在其他癌症的临床试验中具有有效的治疗肝癌的潜力。

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