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.

在过去的一年中，在了解DNA损伤在细胞衰老和衰老中的作用以及了解肝癌中缺失的基因1 （dcl1）的肿瘤抑制功能及其在治疗干预中的潜在应用方面取得了重大进展。DNA损伤的积累不仅在衰老过程中起着重要的作用，而且在细胞衰老的诱导中也起着重要的作用。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是难以捉摸的。为了了解人类衰老过程中DNA损伤反应的定量和定性变化，研究人员在不同年龄的正常个体和沃纳综合征（WS）患者的细胞中检测了磷酸化组蛋白H2AX （γ -H2AX）灶的性质和动态，这些灶特异地发生在DNA双链断裂（DSB）位点。沃纳综合征是一种与早衰、基因组不稳定和癌症发病率增加相关的疾病。该研究表明，γ - h2ax灶的发生率通常随着供者年龄的增长而增加，尽管来自Werner综合征（WS）患者的细胞比来自相同年龄的正常供者的细胞显示出更高的γ - h2ax灶的发生率。在培养中，随着正常和WS成纤维细胞衰老，γ - h2ax病灶发生率进一步增加。对于正常供体和WS供体，DSB修复蛋白对γ - h2ax病灶的募集率与年龄呈负相关，部分原因可能是老年供体中γ - h2ax病灶的生长较慢。由于基因组的稳定性可能取决于DSB的有效加工，其中γ - h2ax病灶的快速形成和DSB修复蛋白的快速积累可能是工具，我们的研究结果表明，这些过程的低效率增加可能导致与正常和病理衰老相关的基因组不稳定。我们小组分离并鉴定的DLC1基因最近被独立证实是一种有效的真正的肿瘤抑制基因。该基因的沉默或低表达在几种常见的人类癌症（如肝癌、乳腺癌、肺癌和前列腺癌）中起着重要作用，最重要的是，dcl1调节的信号通路为治疗干预提供了广泛的靶点。诱导细胞凋亡是肿瘤抑制基因的一个重要特征。在肺和前列腺肿瘤细胞的两项独立研究中，我们发现了DLC1诱导程序性细胞死亡的细胞和分子改变。dcl1在裸鼠体内接种人非小细胞肺癌细胞后，对体外细胞增殖有明显的抑制作用，并能在体内阻止肿瘤的发展。dcl1在肺癌细胞中的转导总是会引起细胞形态的变化，这与该基因的抑癌功能相吻合。DLC1介导的肌动蛋白细胞骨架形态改变和DLC1蛋白核易位发生在抑制细胞迁移和诱导细胞凋亡之前。这些观察结果得出结论，DLC1在细胞质中作为肿瘤细胞增殖和迁移的抑制剂，但在细胞核中作为凋亡的诱导剂。根据我们的证据，dcl1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扩散到解剖远处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抑制肝癌细胞向远处器官的扩散。抑制肝癌细胞向远处脏器扩散与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，这些蛋白在大多数原发性肝肿瘤伴转移中均高度上调。OPN和MMP-9的过表达和dcl1的沉默可能是肝癌不良预后的预后标志。利用腺病毒载体进行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基因表达的膳食成分和药理学药物可能有助于开发预防转移的药物，转移是肝癌进展过程中最有害的事件。在前列腺癌中，我们发现通过表观遗传机制，dcl1的反复下调和失活可能是前列腺癌早期检测的标志，随后我们发现腺病毒介导的dcl1在雄激素非依赖性侵袭性和转移性前列腺肿瘤细胞中的转移抑制了体外细胞增殖、裸鼠致瘤性和诱导细胞凋亡。它还能诱导细胞周期阻滞，抑制RhoA的激活和肌动蛋白应激纤维的形成。在对组蛋白去乙酰化酶抑制剂诱导的细胞死亡有抗性的前列腺肿瘤细胞中，DLC1表达的恢复仅在化学抑制抗凋亡Bcl-2蛋白表达后诱导凋亡。这些结果表明，腺病毒介导的DLC1转移，单独或与其他药物（如Bcl-2抑制剂或组蛋白去乙酰化酶）一起，已经在临床试验中进行了测试，可能证明对侵袭性雄激素不依赖型和转移性前列腺癌的治疗有效。

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