TIMP-2-mediated Tumor Cell Differentiation and Chemo-sensitization Therapy

TIMP-2介导的肿瘤细胞分化和化疗增敏治疗

• 批准号: 7592976
• 负责人: William Stetler-Stevenson
• 金额: $ 69.6万
• 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/7592976
• 关键词: A549; Alternative Splicing; Arthritis; Back; Caenorhabditis elegans; Cancer Patient; Cancer cell line; Cell Differentiation process; Cell Line; Cell surface; Chronic Disease; Class; Clinical Trials; Development; Diabetic Retinopathy; Drosophila genus; Drug Industry; Endothelial Cells; Environment; Enzymes; Epithelial; Event; Exons; Extracellular Matrix; Failure; Family; Gene Family; Gene Structure; Genes; Goals; Growth; Homeostasis; Human; Introns; MMP14 gene; Malignant Neoplasms; Malignant neoplasm of lung; Matrix Metalloproteinase Inhibitor; Matrix Metalloproteinases; Mediating; Mesenchymal; Messenger RNA; Metalloproteases; Metalloproteinase Gene; Molecular; Molecular Structure; Mus; Nature; Neoplasm Metastasis; Nested Genes; Neurites; Normal tissue morphology; Personal Satisfaction; Pharmaceutical Preparations; Phenotype; Protease Inhibitor; Proteins; Range; Relative (related person); Reporting; Role; Synapsins; Testis; Therapeutic; Thinking; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-3; Tissue Inhibitor of Metalloproteinases; Tissues; Tumor Cell Invasion; Wound Healing; Xenograft Model; Zebrafish; brain tissue; chemotherapeutic agent; cytotoxicity; epithelial to mesenchymal transition; extracellular; human MMP14 protein; inhibitor/antagonist; interest; mRNA Differential Displays; member; neoplastic cell; tissue inhibitor of metalloproteinase 4; tumor; tumor growth; tumor progression; tumor xenograft; tumorigenesis

Summary: Endogenous protease inhibitors of several classes can regulate the turnover of the extracellular matrix associated with loss of tissue homeostasis and formation of the tumor microenvironment. The tissue inhibitors of metalloproteinases (TIMPs) are the most specific and well-studied protease inhibitors for the enzymes associated with establishment and progression of the tumor microenvironment. The TIMPs are a family of four small highly conserved proteins. The TIMPs have been identified in species ranging from drosophila, zebra fish and C. elegans to humans, suggesting that these proteins are ancient eukaryotic proteins. The demonstration that TIMP 1 and TIMP-2 inhibited tumor cell invasion and metastasis in mouse xenograft models in the early 1990s, spurred a significant effort on the part of the pharmaceutical industry to develop synthetic MMP inhibitors as potential new cancer therapeutics. Unfortunately, these synthetic MMP inhibitors failed in all subsequent human clinical trials. Although many hypotheses have been put forward to explain the failure of these drugs in human cancer patients, the true nature of this failure remains unknown. The mammalian TIMP family has four members, which share significant homology and structural identity at the protein level. TIMP-2 is unique as a member of the TIMP family in that in addition to inhibiting MMPs TIMP-2 selectively interacts with MT1-MMP to facilitate the cell-surface activation of pro-MMP-2. Thus, TIMP-2 functions both as an inhibitor of MMPs, and is required for the cellular mechanism of pro-MMP-2 activation. TIMP-2 also has a distinct gene structure compared with the other three members of the TIMP family. An interesting relationship exists between the TIMPs and the synapsin gene family in that three members of the TIMP family are nested within the synapsin genes. The synapsin 1 gene nests TIMP-1, synapsin 2 nests TIMP-4 and synapsin 3 nests TIMP-3. TIMP-2 is the only member of the TIMP family that is not nested within a gene of the synapsin family. The synapsin-TIMP gene nesting relationship began phylogenetically as far back as Drosophila. A recent report describes a nested gene within the very large (60 kb) first intron of the TIMP-2 gene, known as differential display clone 8 (DDC8), which at first was thought to encode a testis specific protein. Furthermore, it has been shown that the brain of the TIMP-2-deficient mouse generated by deletion of exon 1 contains TIMP-2 mRNA encoding exons 2-5 downstream of DDC8 sequence, suggesting alternative splicing between these two genes. We have recently demonstrated that exogenous and enhanced expression of endogenous TIMP-2 promotes the differentiation of human microvascular endothelial cells. Jaworski and colleagues have demonstrated that TIMP-2 inhibits neurite proliferation and promotes differentiation. TIMP-2 is frequently under expressed in tumors compared with normal tissue. These observations led us to postulate that re-expression of TIMP-2 in tumor cells and tumor xenografts may influence tumor progression, tumor cell differentiation, epithelial-to-mesenchymal transition and metastatic capacity. We have previously demonstrated that TIMP-2 suppressed the EGF-induced growth of the human lung cancer cell line A549. Preliminary evidence shows that endogenous expression of TIMP-2 in the A549 cell line is very low and the forced expression of TIMP-2 or Ala+TIMP-2 results in over 80 % suppression of tumor growth. We are now examining the mechanism of this effect with respect to the role of TIMP-2 in promoting tumor cell differentiation. In addition we are attempting to characterize the relative contributions of the metalloproteinase inhibitor activity, anti-angiogenic activity and possible direct anti-tumor effects of TIMP-2 to the overall potent anti-tumor activity of this protein

总结：几类内源性蛋白酶抑制剂可以调节细胞的周转， 与组织稳态丧失和肿瘤形成相关的细胞外基质 微环境金属蛋白酶组织抑制剂（TIMPs）是最特异的 和研究充分的蛋白酶抑制剂的酶与建立和 肿瘤微环境的变化。TIMPs是一个四口之家， 保守蛋白TIMPs已在果蝇、斑马、 fish和C.这表明这些蛋白质是古老的真核生物蛋白质。 TIMP-1和TIMP-2抑制小鼠肿瘤细胞侵袭和转移的实验研究 异种移植模型在20世纪90年代初，刺激了一个显着的努力， 制药业开发合成MMP抑制剂作为潜在的新癌症 治疗学不幸的是，这些合成的MMP抑制剂在所有随后的人类中均失败。 临床试验尽管人们提出了许多假说来解释 这些药物在人类癌症患者中，这种失败的真正性质仍然未知。的 哺乳动物TIMP家族有四个成员，它们具有显著的同源性和结构上的同源性。 在蛋白质水平上。TIMP-2作为TIMP家族成员的独特之处在于， 除了抑制MMP外，TIMP-2还选择性地与MT 1-MMP相互作用，以促进MMP的表达。 pro-MMP-2的细胞表面活化。因此，TIMP-2既作为MMP的抑制剂， 是pro-MMP-2激活的细胞机制所必需的。TIMP-2也具有明显的 与TIMP家族的其他三个成员相比，一个有趣 TIMPs和突触蛋白基因家族之间存在关系， TIMP家族嵌套在突触蛋白基因内。突触蛋白1基因嵌套TIMP-1， 突触蛋白2嵌套TIMP-4，突触蛋白3嵌套TIMP-3。TIMP-2是TIMP-1的唯一成员， 不嵌套在突触蛋白家族的基因内的家族。突触蛋白-TIMP基因嵌套 这种关系从果蝇时期就开始了。最近的一份报告描述了 TIMP-2基因的第一个非常大（60 kb）的内含子内的嵌套基因，称为 差异显示克隆8（DDC 8），最初被认为编码睾丸特异性 蛋白此外，已经表明TIMP-2缺陷小鼠的脑产生了 通过缺失外显子1含有编码TIMP-2 mRNA的外显子2-5下游的DDC 8序列， 表明这两个基因之间存在选择性剪接。我们最近已经证明， 内源性TIMP-2的外源性和增强的表达促进了人肝癌细胞的分化， 微血管内皮细胞Jaworski及其同事已经证明TIMP-2 抑制神经突增殖并促进分化。TIMP-2通常在 与正常组织相比，在肿瘤中表达。这些观察使我们假设， TIMP-2在肿瘤细胞和肿瘤异种移植物中的再表达可影响肿瘤进展， 肿瘤细胞分化、上皮向间质转化和转移能力。我们 先前已经证明TIMP-2抑制EGF诱导的人肺的生长 癌细胞系A549。初步证据表明，TIMP-2在肿瘤组织中的内源性表达， A549细胞系中TIMP-2或Ala+TIMP-2的强制表达导致过度表达， 80%抑制肿瘤生长。我们现在正在研究这种影响的机制， TIMP-2在促进肿瘤细胞分化中的作用。此外，我们 试图描述金属蛋白酶抑制剂的相对贡献 TIMP-2的活性、抗血管生成活性和可能的直接抗肿瘤作用， 这种蛋白质的总体有效抗肿瘤活性