Dissecting the metastasis suppressor complex to identify colon cancer biomarkers

剖析转移抑制复合物以鉴定结肠癌生物标志物

• 批准号: 8623108
• 负责人: Sam Thiagalingam
• 金额: $ 17.27万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8623108
• 关键词: Accounting; Apoptosis; Biological Assay; Biological Markers; Biological Models; Cancer Model; Candidate Disease Gene; Cell Culture Techniques; Cell Line; Cells; Chromosomes; Co-Immunoprecipitations; Colon Carcinoma; Colonic Neoplasms; Complex; Computer Simulation; Databases; Defect; Deletion Mutation; Development; Disease; Down-Regulation; Engineering; Epigenetic Process; Event; Exhibits; Fluorouracil; Follow-Up Studies; Frequencies; Gene Expression; Genes; Hypoxia; In Vitro; Link; Loss of Heterozygosity; MADH4 gene; MAP Kinase Gene; MAPK14 gene; MEKs; MMP9 gene; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Meta-Analysis; Metastasis Suppression; Metastatic to; Modeling; Molecular; Molecular Profiling; Mus; Nature; Neoplasm Metastasis; Pathway interactions; Patients; Play; Prognostic Marker; Proteins; Proteomics; RNA Splicing; Reporter; Resistance; Role; SLC2A1 gene; Sampling; Severity of illness; Signal Transduction; Staging; Staining method; Stains; Testing; The Cancer Genome Atlas; Therapeutic; Time; Transcript; Tumor Suppressor Proteins; Vascular Endothelial Growth Factors; Western Blotting; Xenograft Model; adenoma; aerobic glycolysis; base; cancer cell; cofactor; colon cancer cell line; follow-up; hypoxia inducible factor 1; in vivo; knock-down; loss of function; migration; novel; outcome forecast; overexpression; programs; protein complex; public health relevance; research study; transcription factor; tumor; tumor progression

DESCRIPTION (provided by applicant): Loss of heterozygosity (LOH) analysis and follow up studies of sporadic colon cancer enabled us to show that SMAD4 is the primary target tumor suppressor, localized to the minimally lost region at chromosome 18q21-linked to an advanced stage disease. Subsequent studies by others have confirmed these initial observations and have established that the frequency of SMAD4 mutations/deletions increases as the cancer progresses from adenomas to the metastatic disease. Overall, these findings are consistent with loss of Smad4 function in metastatic colon cancer. In an effort to delineate a molecular basis for an association between SMAD4 deficiency and metastatic colon cancer, we have begun to use appropriately engineered model systems. Our preliminary studies showed that the SMAD4 defect was responsible for an increase in the levels of VEGF, overactivation of MEK-Erk and p38-MAPK auxiliary pathways, enhanced migration of colon cancer cells with a corresponding increase in MMP9, overexpression of GLUT1 under hypoxia, increased aerobic glycolysis and resistance to 5-FU-mediated apoptosis. We also found that overexpression of Smad4 in the model colon cancer cells with SMAD4 deficiency inhibited VEGF reporter activity and Smad4 physically interacts with specific transcription factors (TFs) such as HIF1? to potentially regulat metastatic progression of colon cancer. While the molecular characterizations are consistent with the notion that Smad4 may play a central role in forming a colon cancer metastasis suppressor complex consisting of various transcription factors and cofactors to collectively block colon cancer metastasis, direct targeting for loss of Smad4 function could only account for approximately 30% of tumors that harbor LOH at 18q21. Therefore, metastatic colon cancers that retained intact Smad4 could also progress through inactivation of the other components of the complex that suppresses the metastatic program. In this proposal, we will test the hypothesis that metastatic colon cancers which retain Smad4 exhibit alterations in the other components of the colon cancer metastasis suppressor complex. Thus, we predict that by unraveling the composition of the colon cancer metastasis suppressor complex, one would uncover novel prognostic biomarkers that are alternatively targeted for inactivation in metastatic colon cancer. Here, we outline a strategy using the model cell lines to isolate and characterize the components of the colon cancer metastasis suppressor complex consisting of Smad4 to (1) investigate the nature of the higher order protein complexes that are assembled and dissolved under the conditions of intact and defective Smad4 signaling using proteomic analysis to identify TFs and co-factors as candidate prognostic biomarkers; (2) examine if dysregulation of these other factors of the metastasis suppressor complex disrupts its functionality; and (3) determine if defects/deficiency in the alternate targets of Smad4 metastasis suppressor complex could serve as prognostic biomarkers for colon cancer. In summary, the proposed studies may unravel novel prognostic biomarkers for metastatic colon cancer and it could aid the development of personalized therapy.

描述（由申请人提供）：散发性结肠癌的杂合性丢失（洛）分析和随访研究使我们能够显示SMAD 4是主要的靶肿瘤抑制因子，定位于染色体18 q21的最小丢失区域-与晚期疾病相关。其他人的后续研究证实了这些初步观察结果，并确定SMAD 4突变/缺失的频率随着癌症从腺瘤进展到转移性疾病而增加。总的来说，这些发现与转移性结肠癌中Smad 4功能的丧失一致。在努力描绘SMAD 4缺陷和转移性结肠癌之间的关联的分子基础，我们已经开始使用适当的工程模型系统。我们的初步研究表明，SMAD 4缺陷导致VEGF水平增加，MEK-Erk和p38-MAPK辅助通路过度激活，结肠癌细胞迁移增强，MMP 9相应增加，缺氧条件下GLUT 1过表达，有氧糖酵解增加和对5-FU介导的凋亡的抵抗。我们还发现，Smad 4在模型结肠癌细胞SMAD 4缺陷抑制VEGF报告活性和Smad 4的过度表达与特定的转录因子（TF），如HIF 1？to potentially潜在regulat调节metastatic转移progression进展of colon结肠cancer癌症.虽然分子表征与Smad 4可能在形成由各种转录因子和辅因子组成的结肠癌转移抑制复合物以共同阻断结肠癌转移的概念一致，但直接靶向Smad 4功能丧失只能解释约30%的在18 q21处具有洛的肿瘤。因此，保留完整Smad 4的转移性结肠癌也可以通过抑制转移程序的复合物的其他组分的失活而进展。在这个建议中，我们将测试的假设，保留Smad 4的转移性结肠癌表现出结肠癌转移抑制复合物的其他成分的变化。因此，我们预测，通过解开结肠癌转移抑制复合物的组成，人们将发现新的预后生物标志物，这些生物标志物可替代地靶向转移性结肠癌中的失活。在此，我们概述了一种使用模型细胞系来分离和表征由Smad 4组成的结肠癌转移抑制复合物的组分的策略，以（1）使用蛋白质组学分析来研究在完整和有缺陷的Smad 4信号传导的条件下组装和溶解的高阶蛋白质复合物的性质，以鉴定TF和辅因子作为候选预后生物标志物;（2）检查转移抑制复合物的这些其他因素的失调是否会破坏其功能;以及（3）确定是否 Smad 4转移抑制复合物的替代靶点的缺陷/缺陷可以作为结肠癌的预后生物标志物。总之，拟议的研究可能揭示转移性结肠癌的新预后生物标志物，并有助于个性化治疗的发展。

项目成果

Methamphetamine-induced psychosis is associated with DNA hypomethylation and increased expression of AKT1 and key dopaminergic genes.

• DOI: 10.1002/ajmg.b.32506
• 发表时间: 2016-12
• 期刊: American journal of medical genetics. Part B, Neuropsychiatric genetics : the official publication of the International Society of Psychiatric Genetics
• 作者: Nohesara S;Ghadirivasfi M;Barati M;Ghasemzadeh MR;Narimani S;Mousavi-Behbahani Z;Joghataei M;Soleimani M;Taban M;Mehrabi S;Thiagalingam S;Abdolmaleky HM
• 通讯作者: Abdolmaleky HM