Molecular Cytogenetics of Solid Tumors

实体瘤的分子细胞遗传学

• 批准号: 7732973
• 负责人: NICOLAE POPESCU
• 金额: $ 98.51万
• 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/7732973
• 关键词: Actins; Adenovirus Vector; Adenoviruses; Age; Aging; Aging-Related Process; Androgens; Apoptosis; Apoptosis Promoter; Breast; Cancer Etiology; Cancer Prognosis; Cell Aging; Cell Cycle Arrest; Cell Death; Cell Migration Inhibition function; Cell Migration Inhibition measurement; Cell Nucleus; Cell Proliferation; Cells; Cellular Morphology; Chemicals; Clinical Trials; Complex; Cytoplasm; Cytoskeleton; Cytoskeleton Alteration; DLC1 gene; DNA Damage; DNA Double Strand Break; DNA Repair; Development; Diagnosis; Disease; Distant; Double Strand Break Repair; Down-Regulation; Epigenetic Process; Event; Exhibits; Fibroblasts; Gelatinase B; Gene Expression; Gene Transfer; Genes; Genome Stability; Genomic Instability; Genomics; Goals; Growth; Histone Deacetylase Inhibitor; Histones; Human; Immigration; In Vitro; Incidence; Individual; Induction of Apoptosis; Lead; Link; Liver; Liver neoplasms; Lung; Malignant Epithelial Cell; Malignant Neoplasms; Malignant neoplasm of liver; Malignant neoplasm of lung; Malignant neoplasm of prostate; Mediating; Metastasis Suppressor Genes; Metastatic Prostate Cancer; Molecular; Molecular Biology; Molecular Cytogenetics; Mutation; Nature; Neoplasm Metastasis; Normal Cell; Nuclear Translocation; Nude Mice; Organ; Patients; Play; Premature aging syndrome; Prevention; Primary Neoplasm; Primary carcinoma of the liver cells; Process; Prognostic Marker; Prostatic Neoplasms; Proteins; Range; Rate; Recurrence; Research; Resistance; Role; Screening for Prostate Cancer; Signal Pathway; Site; Solid Neoplasm; Stress Fibers; Testing; Therapeutic Intervention; Tumor Suppressor Genes; Tumor Suppressor Proteins; Tumorigenicity; Werner Syndrome; age related; base; cancer cell; cancer therapy; dietary constituent; drug development; gene function; gene therapy; human DLC1 protein; human H2AX protein; in vivo; inhibitor/antagonist; lung Carcinoma; mortality; neoplastic cell; novel; osteopontin; outcome forecast; pathological aging; prevent; programs; protein expression; response; restoration; senescence; tumor; tumor progression

In the past year significant progress has been made in understanding the role of DNA damage in cellular aging and senescence and in the understanding of the Deleted in Liver Cancer 1, (DLC1), genes tumor suppressive function and its potential use for therapeutic interventions. Accumulation of DNA damage may play an essential role not only in the process of aging but also in induction of cellular senescence. The ability of cells to sense and repair DNA damage declines with age. However, the underlying molecular mechanism for this age-dependent decline is still elusive. To understand quantitative and qualitative changes in the DNA damage response during human aging, the nature and dynamics of phosphorylated histone H2AX (gamma-H2AX) foci, which occur specifically at sites of DNA double-strand breaks (DSB), were examined in cells from normal individuals of different age and from patients with Werner syndrome (WS), a disorder associated with premature aging, genomic instability and increased incidence of cancer. This study showed that the incidence of gamma-H2AX foci generally increases with donors age, although the cells derived from patients with Werner syndrome (WS) exhibited considerably higher incidence of gamma-H2AX foci than those taken from normal donors of comparable age. Further increases in gamma-H2AX focal incidence occurred in culture as both normal and WS fibroblasts progressed toward senescence. The rates of recruitment of DSB repair proteins to gamma-H2AX foci correlated inversely with age for both normal and WS donors, perhaps due in part to the slower growth of gamma-H2AX foci in older donors. Since genomic stability may depend on the efficient processing of DSBs where the rapid formation of gamma-H2AX foci and the rapid accumulation of DSB repair proteins may be instrumental, our findings suggest that increasing inefficiency in these processes may contribute to genome instability associated with normal and pathological aging. The DLC1 gene, isolated and characterized by our group, has recently been independently confirmed as a potent bona fide tumor suppressor gene. Silencing or underexpression of this gene plays an important role in several common human cancers such as liver, breast, lung and prostate cancer and, most significantly, signaling pathways modulated by DLC1 provide wide range of targets for therapeutic interventions. Induction of apoptosis is a major attribute of tumor suppressor gene. In two independent studies with lung and prostate tumor cells, we identified cellular and molecular alterations indicative of the induction of programmed cell death by DLC1. DLC1 has a dramatic inhibitory effect on in vitro cell proliferation and prevented in vivo the development of tumors after inoculation of human non-small cell lung carcinoma cells in nude mice. Transduction of DLC1 in lung cancer cells invariably induced changes in cell morphology corroborative of the tumor suppressor function of the gene. DLC1-mediated actin cytoskeleton-based morphological alterations, and DLC1 protein nuclear translocation occur prior to inhibition of cell migration and before to the induction of apoptosis. These observations led to the conclusion that DLC1 functions in the cytoplasm as an inhibitor of tumor cell proliferation and migration, but in the nucleus as an inducer of apoptosis. Based on our evidence, DLC1 is now considered a metastasis suppressor gene. The process of tumor cell dissemination from the locally growing primary tumors to metastasis in anatomically distant sites is the leading cause of cancer mortality, representing over 90% of cancer casualties. Metastatic disease is a complex process involving various cellular and genetic alterations. We showed that DLC1 inhibits the spread of liver cancer cells to distant organs. The inhibition of liver cancer cell dissemination to distant organs was associated with reduction of RhoA activity, cytoskeleton alterations, down regulation of osteopontin (OPN) and matrix metalloproteinase-9 (MMP9) expression, which are highly up regulated in most primary liver tumors with associated metastases. Over-expression of OPN and MMP-9 and silencing of DLC1 may provide a prognostic marker for unfavorable prognosis of liver cancer. DLC1 gene therapy using adenoviral vector, as the most useful vehicle for gene transfer, is a realistic prospect for prevention of HCC dissemination. Also, searching for dietary constituents and pharmacological agents that up-regulate DLC-1 gene expression could lead to the development of drugs that might be useful for prevention of metastasis, the most harmful event during liver cancer progression. In prostate cancer, we found that recurrent downregulation and inactivation of DLC1 by epigenetic mechanisms may serve as an marker for early detection of prostate cancer and subsequently we showed that adenovirus-mediated DLC1 transfer in androgen-independent aggressive and metastatic prostate tumor cells inhibited cell proliferation in vitro, their tumorigenicity in nude mice, and induced apoptosis. It also induced cell cycle arrest, inhibited the activation of RhoA and the formation of actin stress fibers. In prostate tumor cells that are resistant to histone deacetylase inhibitors-induced cell death, restoration of DLC1 expression induced apoptosis only after chemical inhibition of the antiapoptotic Bcl-2 protein expression. These results suggest that adenovirus-mediated DLC1 transfer, alone or together with other agents such as inhibitors of Bcl-2, or histone deacetylases that were already tested in clinical trials might prove effective in the treatment of aggressive androgene independent and metastatic prostate cancer.

在过去的一年里，在了解 DNA 损伤在细胞老化和衰老中的作用以及对肝癌删除基因 1 (DLC1)、基因肿瘤抑制功能及其治疗干预的潜在用途方面取得了重大进展。 DNA损伤的积累不仅在衰老过程中而且在诱导细胞衰老中发挥着重要作用。细胞感知和修复 DNA 损伤的能力随着年龄的增长而下降。然而，这种年龄依赖性衰退的潜在分子机制仍然难以捉摸。为了了解人类衰老过程中 DNA 损伤反应的定量和定性变化，我们在不同年龄的正常个体和维尔纳综合征 (WS) 患者的细胞中检查了磷酸化组蛋白 H2AX (gamma-H2AX) 灶的性质和动态，这些磷酸化组蛋白 H2AX (gamma-H2AX) 灶专门发生在 DNA 双链断裂 (DSB) 位点。维尔纳综合征 (WS) 是一种与过早衰老、基因组不稳定和癌症发病率增加相关的疾病。这项研究表明，γ-H2AX 病灶的发生率通常随着供体年龄的增加而增加，尽管来自维尔纳综合征 (WS) 患者的细胞表现出 γ-H2AX 病灶的发生率明显高于取自同等年龄的正常供体的细胞。随着正常成纤维细胞和 WS 成纤维细胞走向衰老，培养物中 γ-H2AX 局灶发生率进一步增加。 DSB 修复蛋白向 γ-H2AX 病灶的募集率与正常供体和 WS 供体的年龄成反比，部分原因可能是老年供体中 γ-H2AX 病灶生长较慢。由于基因组稳定性可能取决于 DSB 的有效处理，其中 γ-H2AX 焦点的快速形成和 DSB 修复蛋白的快速积累可能发挥作用，因此我们的研究结果表明，这些过程效率低下的增加可能会导致与正常和病理性衰老相关的基因组不稳定。我们小组分离并鉴定的 DLC1 基因最近已被独立证实为有效的真正肿瘤抑制基因。该基因的沉默或表达不足在几种常见的人类癌症中发挥着重要作用，例如肝癌、乳腺癌、肺癌和前列腺癌，最重要的是，DLC1 调节的信号通路为治疗干预提供了广泛的靶点。诱导细胞凋亡是抑癌基因的一个主要属性。在两项针对肺和前列腺肿瘤细胞的独立研究中，我们发现了表明 DLC1 诱导程序性细胞死亡的细胞和分子改变。 DLC1对体外细胞增殖具有显着的抑制作用，并在体内接种人非小细胞肺癌细胞裸鼠后阻止肿瘤的发展。肺癌细胞中 DLC1 的转导总是会引起细胞形态的变化，证实了该基因的肿瘤抑制功能。 DLC1 介导的基于肌动蛋白细胞骨架的形态学改变和 DLC1 蛋白核转位发生在抑制细胞迁移之前和诱导细胞凋亡之前。这些观察结果得出这样的结论：DLC1 在细胞质中作为肿瘤细胞增殖和迁移的抑制剂发挥作用，但在细胞核中作为细胞凋亡的诱导剂。根据我们的证据，DLC1 现在被认为是一种转移抑制基因。肿瘤细胞从局部生长的原发肿瘤向解剖学上较远部位的转移的过程是癌症死亡的主要原因，占癌症死亡人数的 90% 以上。转移性疾病是一个复杂的过程，涉及各种细胞和遗传改变。我们发现 DLC1 可以抑制肝癌细胞向远处器官的扩散。肝癌细胞向远处器官播散的抑制与 RhoA 活性降低、细胞骨架改变、骨桥蛋白 (OPN) 和基质金属蛋白酶 9 (MMP9) 表达下调有关，而这些表达在大多数具有相关转移的原发性肝肿瘤中高度上调。 OPN和MMP-9的过度表达以及DLC1的沉默可能为肝癌不良预后提供预后标志。使用腺病毒载体的 DLC1 基因治疗作为最有用的基因转移载体，是预防 HCC 传播的现实前景。此外，寻找上调 DLC-1 基因表达的饮食成分和药物制剂可能有助于开发出可能有助于预防转移（肝癌进展过程中最有害的事件）的药物。在前列腺癌中，我们发现表观遗传机制引起的 DLC1 反复下调和失活可以作为前列腺癌早期检测的标志物，随后我们发现，在不依赖雄激素的侵袭性和转移性前列腺肿瘤细胞中，腺病毒介导的 DLC1 转移可在体外抑制细胞增殖，在裸鼠中抑制其致瘤性，并诱导前列腺癌的发生。 细胞凋亡。它还诱导细胞周期停滞，抑制 RhoA 的激活和肌动蛋白应激纤维的形成。在对组蛋白脱乙酰酶抑制剂诱导的细胞死亡具有抵抗力的前列腺肿瘤细胞中，只有在化学抑制抗凋亡 Bcl-2 蛋白表达后，DLC1 表达的恢复才能诱导细胞凋亡。这些结果表明，腺病毒介导的 DLC1 转移，单独或与其他药物（例如已在临床试验中测试的 Bcl-2 抑制剂或组蛋白脱乙酰酶）一起，可能在治疗侵袭性雄激素非依赖性和转移性前列腺癌中有效。

项目成果

DNA variants of DLC-1, a candidate tumor suppressor gene in human hepatocellular carcinoma.

• DOI: 10.3892/ijo.23.1.133
• 发表时间: 2003-07
• 期刊: International journal of oncology
• 影响因子: 5.2
• 作者: Sang-won Park;M. Durkin;S. Thorgeirsson;N. Popescu

Identification and characterization of a gene encoding a putative mouse Rho GTPase activating protein gene 8, Arhgap8.

编码假定的小鼠 Rho GTPase 激活蛋白基因 8（Arhgap8）的基因的鉴定和表征。

• DOI: 10.1016/s0378-1119(02)01143-5
• 发表时间: 2003
• 期刊: Gene
• 影响因子: 3.5
• 作者: Shan,Zhihong;Haaf,Thomas;Popescu,NicholasC
• 通讯作者: Popescu,NicholasC

DLC1 suppresses distant dissemination of human hepatocellular carcinoma cells in nude mice through reduction of RhoA GTPase activity, actin cytoskeletal disruption and down-regulation of genes involved in metastasis.

• DOI: 10.3892/ijo_32_6_1285
• 发表时间: 1992-06
• 期刊: International journal of oncology
• 影响因子: 5.2
• 作者: Xiaoling Zhou;D. Zimonjic;Sang-won Park;Xuyu Yang;M. Durkin;N. Popescu

SMAD5 gene expression, rearrangements, copy number, and amplification at fragile site FRA5C in human hepatocellular carcinoma.

人肝细胞癌中 SMAD5 基因表达、重排、拷贝数和脆弱位点 FRA5C 的扩增。

• DOI: 10.1016/s1476-5586(03)80041-6
• 发表时间: 2003
• 期刊: Neoplasia (New York, N.Y.)
• 作者: Zimonjic,DrazenB;Durkin,MarianE;Keck-Waggoner,CatherineL;Park,Sang-Won;Thorgeirsson,SnorriS;Popescu,NicholasC
• 通讯作者: Popescu,NicholasC

Fragile sites and cancer genes on the short arm of chromosome 8.

8 号染色体短臂上的脆弱位点和癌症基因。

• DOI: 10.1016/s1470-2045(04)01377-4
• 发表时间: 2004
• 期刊: The lancet oncology
• 作者: Popescu,NicholasC