主題一：利用化學蛋白質體學研究LYF-17抑制人類乳癌細胞株MDA-MB-435增生標的蛋白
LYF-17屬於2-PN的延伸化合藥物，這類藥物在之前的文獻報導中發現可以抑制微管聚合等功用。
化學蛋白質體學可以被用來確認生物體的標的蛋白並且應用它們於藥物的發現及發展。在此我們利用相關的完善技術與方法去快速地確認藥物的標的蛋白，以及探討藥物的發展。在生物體訊息路徑中，蛋白質與LYF-17的互相影響是一個重要的關鍵點，LYF-17的加入會影響到許多不同的重要蛋白質。因此，我們利用色層分析法、二維電泳以及質譜儀來確認LYF-17在人類乳癌細胞株MDA-MB-435中會影響到那些標的蛋白質。由我們的結果可以發現LYF-17的標的蛋白有：Protein disulfide isomerase family A member 3(PDIA3)、zinc finger protein、beta-site APP-cleaving enzyme 2(BACE2)、T cell receptor alpha(TCRA)、CD44、dysferlin、Ribosomal protein及Microtubule-associated protein 1B(MAP1B)等。
主題二：LYF-17藉由誘導miR-200c和miR-141的表現抑制人類乳癌細胞上皮-間質轉化
MicroRNAs(miRNAs)在mRNA的轉錄和蛋白質的表現中扮演重要的角色。最近，miRNAs在許多癌症細胞中的功能是可以作為抑癌基因或是致癌基因。許多相關研究迅速地興起，並且指出特定的miRNAs在人類癌症上也許扮演一個角色。因此，我們想測試LYF-17是否可以改變人類乳癌細胞miRNA的表現量。我們發現在投予LYF-17之後，會使miR-200c 和miR-141表現量上升，進而影響到ZEB1蛋白，進一步調節上皮細胞轉型成間質細胞 (epithelial to mesenchymal transition，EMT)的轉換。EMT現象會導致腫瘤容易轉移，調控EMT的相關蛋白因子包含：E-cadherin 和Vimentin。在投予LYF-17治療以後，我們發現miR-200c和miR141過度表現會導致ZEB1和Vimentin的蛋白表現量減少，而E-cadherin的蛋白表現量則會上升 。
Section I：Chemical proteomic characterization of the LYF-17 inhibits the proliferation in human breast cancer MDA-MB-435
LYF-17 is a kind of 2-PN to spread out extends the thing. Many beneficial properties have been attributed to 2-PN, including inhibition of tubulin polymerization etc.
A fundamental goal of chemical proteomics is to identify target proteins for bioactive small molecules and then apply them to drug discovery and development as valid and drugable targets. Here, we introduce integrated technologies for the rapid identification of target proteins, methodologies for validating them as drugable targets, and applications of chemical proteomics in drug discovery and development. Protein interaction with LYF-17 is a critical step in the effects of LYF-17 on the regulation of various key proteins involved in signal transduction. We have identified a novel molecular target of LYF-17 using affinity chromatography, two-dimensional electrophoresis, and mass spectrometry for protein identification. We found the spots of interest were identified as the Protein disulfide isomerase family A, member 3(PDIA3)；zinc finger protein；beta-site APP-cleaving enzyme 2(BACE2)；T cell receptor alpha(TCRA)；CD44；dysferlin；Ribosomal protein and Microtubule-associated protein 1B (MAP1B).
Section II：LYF-17 Inhibits EMT via the Induction of miR-200c and miR-141 in Human Breast Cancer Cells
MicroRNAs (miRNAs) have been reported that they play important roles in mRNA transcription and protein expression. Recently, miRNAs function as either tumor suppressor genes or oncogenes in many cancer cells. Evidence is emerging rapidly that specific miRNAs might play a role in human cancer pathogenesis. In the current study, we test whether LYF-17 could alter the miRNA expression profiles. We found that LYF-17 induced the expression of miR-200c and miR-141 that regulated epithelial to mesenchymal transition (EMT) by targeting ZEB1. EMT facilitates tissue remodelling during embryonic development and is viewed as an essential early step in tumour metastasis. E-cadherin and Vimentine are target protein for EMT. After treatment of LYF-17, we could show that overexpression of miR-200c and miR-141 led to reduce expression of ZEB1 and Vimentin However, overexpression of miR-200c and miR-141 led to induce expression of E-cadherin, and the other candidate genes in undifferentiated cancer cells.
