微小RNA是内源性小非编码RNA，在肿瘤生成中扮演重要角色。Brucein D(BD)是一种B. javanica果实提取物，已被报道在胰腺癌中具有抗肿瘤作用。在此研究中，我们证明了BD在体内和体外均可抑制肝癌细胞生长。为了研究BD是否通过调节微小RNA来执行其抗肿瘤功能，我们进行了一个肿瘤微小RNA定量PCR阵列谱分析。此阵列包括95个已被报道与肿瘤有关的微小RNA。通过对比BD处理前后微小RNA谱的变化，我们发现微小RNA-95在BD处理后被显著下调了。其后促凋亡的CUGBP2被确定为微小RNA-95的下游靶基因。 / 胰腺癌是一种预后很差的恶性肿瘤，常常在确诊时已发生转移。为了找出在胰腺癌转移过程中发挥决定性作用的基因，我们进行了全基因组范围的RNA干扰筛选。一个包含针对全部人类基因的shRNA文库被导入胰腺癌细胞系capan-2.然后将这些细胞移植到裸鼠的胰腺中来建立一个原位胰腺癌小鼠模型。我们的假设是下调某个基因会促使低转移潜力的capan-2细胞转移到肝脏。通过从肝转移结节中回收shRNA模板，我们找到了几个推定的转移抑制基因。其中之一，SOX9，通过体内实验验证，证明下调SOX9基因的表达可促进胰腺癌转移。 / 化疗适用于进展期胰腺癌病人。然而他们对一线化疗药吉西他滨的反应并不乐观，这进一步使胰腺癌的预后变差。我们展开了一个全基因组范围的RNA干扰筛选来确定一些在化疗耐药过程中起关键作用的基因。携带上述shRNA文库的capan-2细胞被用于吉西他滨药物处理之下的筛选。通过微阵列分析，一些基因被筛选成为可影响癌细胞对药物敏感性的潜在的靶基因。通过进一步验证，LLGL1基因被确定为在调节癌细胞对化疗敏感性过程中起重要作用的基因。 / MicroRNAs (miRNAs) are endogenous small non-coding RNAs that have been shown to play important roles in tumorigenesis. Brucein D (BD), a chemical compound isolated from Brucea javanica fruit, has previously been reported to have anti-cancer effect in pancreatic cancer. In this study, we showed that BD also inhibited the growth of liver cancer cells both in vitro and in vivo. To investigate whether BD exerts its anti-cancer effect through regulation of miRNAs, we performed a cancer miRNA qPCR array profiling. From the profiling, miR-95 was found to be significantly down-regulated after BD treatment. Subsequently, a pro-apoptotic gene CUGBP2 was identified as a direct downstream target of miR-95. These findings suggested BD suppressed liver cancer cell growth through down-regulation of miR-95 and reinforcing CUGBP2. / Pancreatic cancer is an aggressive malignancy with extremely poor prognosis. It is usually diagnosed when metastases are already present. To identify genes that play critical roles in the processes of pancreatic cancer metastasis, a whole genome RNAi screening was performed. An shRNA library targeting all human genes was introduced into a human pancreatic cancer cell line capan-2. The infected cells were then transplanted into the pancreas of nude mice. Because capan-2 is of low metastatic potential, we hypothesized that knocking down of metastasis suppressor genes would facilitate capan-2 cells to spread to the liver. By retrieving shRNA templates from the liver metastatic nodules, several candidate genes were found. One of them, SOX9, has been validated as metastasis suppressor gene in vivo, implying that loss of expression of SOX9 promotes pancreatic cancer metastasis. / Chemotherapy is recommended for patients of pancreatic cancer in advanced stage. However, their response to the first-line chemotherapy drug gemcitabine is not satisfactory. A genome-wide RNAi screening was conducted to identify genes that were critical in chemotherapy resistance. Capan-2 cells containing the above shRNA library were applied for the screening under gemcitabine treatment. Through microarray analysis, a number of genes were screened as potential gemcitabine sensitivity genes. Validation experiments implied that the gene LLGL1 may play an important role in modulating pancreatic cancer cells’ sensitivity to gemcitabine. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xia, Tian. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 125-134). / Abstracts also in Chinese. / Chapter Abstract --- p.I / Chapter Acknowledgements --- p.V / Chapter Abbreviations --- p.VI / Chapter List of Figures --- p.XV / Chapter List of Tables --- p.XVI / Chapter Part I: --- Brucein D-modulated microRNA-95 expression inhibits hepatocellular carcinoma cell growth --- p.1 / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Hepatocellular carcinoma --- p.1 / Chapter 1.1.1 --- Definition and classification --- p.1 / Chapter 1.1.2 --- Epidemiology --- p.1 / Chapter 1.1.3 --- Etiology --- p.3 / Chapter 1.1.4 --- Molecular pathogenesis of HCC --- p.4 / Chapter 1.1.4.1 --- Genomic instability --- p.4 / Chapter 1.1.4.2 --- Deregulation of key signaling pathways --- p.5 / Chapter 1.1.4.3 --- Epigenetic changes of HCC --- p.6 / Chapter 1.1.4.4 --- Two models of HCC pathogenesis --- p.7 / Chapter 1.1.5 --- Therapeutic methods and prognosis of HCC --- p.8 / Chapter 1.2 --- Apoptosis --- p.9 / Chapter 1.2.1 --- Types of cell death --- p.9 / Chapter 1.2.2 --- Apoptosis --- p.10 / Chapter 1.2.3 --- Morphological features of apoptosis --- p.10 / Chapter 1.2.4 --- Molecular mechanisms of apoptosis --- p.11 / Chapter 1.2.5 --- Apoptosis and cancer --- p.13 / Chapter 1.2.5.1 --- Imbalance of pro-apoptotic proteins and anti-apoptotic proteins --- p.13 / Chapter 1.2.5.2 --- Impaired caspases activity --- p.14 / Chapter 1.2.5.3 --- Deregulated death receptor signaling --- p.15 / Chapter 1.2.6 --- Cancer therapy targeting apoptotic defects --- p.15 / Chapter 1.3 --- microRNA --- p.16 / Chapter 1.3.1 --- Overview --- p.16 / Chapter 1.3.2 --- Biogenesis and maturation of microRNA --- p.17 / Chapter 1.3.3 --- Gene silencing by microRNA --- p.18 / Chapter 1.3.4 --- MicroRNA and cancers --- p.19 / Chapter 1.3.5 --- MicroRNA’s involvement in HCC --- p.21 / Chapter 1.3.6 --- Involvement of miR-95 in cancer --- p.22 / Chapter 1.4 --- Brucein D --- p.22 / Chapter 1.5 --- Aims of study --- p.23 / Chapter 2 --- Materials and Methods --- p.25 / Chapter 2.1 --- Cell Culture --- p.25 / Chapter 2.1.1 --- Mammalian Cell Culture --- p.25 / Chapter 2.1.2 --- Preparation of cell stock --- p.25 / Chapter 2.1.3 --- Cell recovery from liquid nitrogen stock --- p.26 / Chapter 2.1.4 --- Preparation of drugs for treatments --- p.26 / Chapter 2.1.5 --- Drug treatment --- p.26 / Chapter 2.1.6 --- Transfection of siRNA --- p.27 / Chapter 2.1.7 --- MTT Assay --- p.28 / Chapter 2.1.8 --- Luciferase reporter assays --- p.28 / Chapter 2.1.9 --- Annexin V Assay --- p.29 / Chapter 2.2 --- In vivo mouse model --- p.29 / Chapter 2.3 --- Tunel Assay (Terminal deoxynucleotide transferase dUTP Nick End Labeling Assay) --- p.30 / Chapter 2.4 --- RNA manipulation --- p.31 / Chapter 2.4.1 --- RNA Isolation --- p.31 / Chapter 2.4.2 --- Synthesis of cDNA from miRNA --- p.32 / Chapter 2.4.3 --- Synthesis of cDNA from RNA and quantitative PCR --- p.33 / Chapter 2.4.4 --- miRNA qPCR array --- p.34 / Chapter 2.5 --- DNA manipulation --- p.34 / Chapter 2.5.1 --- Agarose gel electrophoresis and purification of DNA --- p.34 / Chapter 2.5.2 --- Restriction enzymes digestion --- p.35 / Chapter 2.5.3 --- Ligation of DNA fragments --- p.36 / Chapter 2.5.4 --- Polymerase chain reaction --- p.36 / Chapter 2.5.5 --- Preparation of competent E. coli cells --- p.37 / Chapter 2.5.6 --- Transformation of E. coli cells --- p.37 / Chapter 2.5.7 --- Small scale plasmid isolation from E. coli (mini-prep) --- p.38 / Chapter 3 --- Results --- p.39 / Chapter 3.1 --- Brucein D inhibited the growth of HCC cells both in vitro and in vivo --- p.39 / Chapter 3.2 --- BD induced apoptosis in HCC cells --- p.43 / Chapter 3.3 --- miR-95 is an target of BD to modulate cell growth --- p.46 / Chapter 3.4 --- Identification of CUGBP2 as a downstream target of miR-95 --- p.55 / Chapter 4 --- Discussion --- p.60 / Chapter Part II: --- Genome-wide RNAi screening identifies tumor metastasis suppressor genes and drug sensitivity genes in pancreatic cancer --- p.65 / Chapter 1 --- Introduction --- p.65 / Chapter 1.1 --- Pancreatic cancer --- p.65 / Chapter 1.1.1 --- Overview --- p.65 / Chapter 1.1.2 --- Pancreatic ductal adenocarcinoma (PDAC) --- p.67 / Chapter 1.1.3 --- Molecular basis of PDAC --- p.67 / Chapter 1.1.3.1 --- KRAS --- p.67 / Chapter 1.1.3.2 --- TP53 --- p.68 / Chapter 1.1.3.3 --- CDKN2A --- p.69 / Chapter 1.1.4 --- Gemcitabine treatment in PDAC --- p.69 / Chapter 1.2 --- Metastasis --- p.71 / Chapter 1.2.1 --- Overview --- p.71 / Chapter 1.2.2 --- The stepwise process of metastasis --- p.72 / Chapter 1.2.3 --- Metastasis of pancreatic cancer --- p.74 / Chapter 1.3 --- SOX9 --- p.75 / Chapter 1.4 --- Aims of study --- p.77 / Chapter 2 --- Materials and Method --- p.78 / Chapter 2.1 --- Cell culture --- p.78 / Chapter 2.1.1 --- Mammalian Cell Culture --- p.78 / Chapter 2.1.2 --- MTT Assay --- p.78 / Chapter 2.1.3 --- Colony formation assay --- p.79 / Chapter 2.1.4 --- Wound healing assay --- p.79 / Chapter 2.1.5 --- Transwell migration chamber assay --- p.80 / Chapter 2.1.6 --- Immunocytochemistry --- p.80 / Chapter 2.1.7 --- Transient transfection of siRNA --- p.81 / Chapter 2.2 --- Establishment of in-vivo and in-vitro models --- p.82 / Chapter 2.2.1 --- shRNA library introduction --- p.82 / Chapter 2.2.2 --- Establishment of the orthotopic pancreatic cancer mouse model --- p.82 / Chapter 2.2.3 --- Package of lentivirus expressing shRNA --- p.83 / Chapter 2.2.4 --- Generation of stable cell line expressing shRNA --- p.84 / Chapter 2.3 --- DNA manipulation --- p.84 / Chapter 2.3.1 --- Large scale plasmid isolation from E. coli (maxi-prep) --- p.84 / Chapter 2.4 --- Analysis of Protein --- p.85 / Chapter 2.4.1 --- Preparation of protein cell lysates --- p.85 / Chapter 2.4.2 --- Protein concentration determination --- p.86 / Chapter 2.4.3 --- SDS-PAGE --- p.86 / Chapter 2.4.4 --- Immunoblotting (Western blotting) --- p.87 / Chapter 2.5 --- RNA manipulations --- p.88 / Chapter 2.5.1 --- RNA Isolation --- p.88 / Chapter 2.5.2 --- Synthesis of cDNA from RNA and quantitative PCR --- p.89 / Chapter 2.6 --- Analysis of Clinical Samples --- p.90 / Chapter 2.6.1 --- Clinical specimens --- p.90 / Chapter 2.6.2 --- Immunohistochemistry --- p.90 / Chapter 3 --- Results --- p.92 / Chapter 3.1 --- Genome-wide RNAi screening identifies genes as metastasis suppressors in an orthotopic pancreatic cancer mouse model --- p.92 / Chapter 3.2 --- SOX9 is a metastasis suppressor gene in pancreatic cancer --- p.97 / Chapter 3.3 --- Investigation into cellular functions of SOX9 --- p.102 / Chapter 3.3.1 --- SOX9’s effect on cell growth --- p.102 / Chapter 3.3.2 --- SOX9’s effect on cell migration --- p.105 / Chapter 3.4 --- Implication of SOX9 in human pancreatic cancer samples --- p.109 / Chapter 3.5 --- Genome-wide RNAi screening for the identification of gemcitabine sensitivity genes --- p.113 / Chapter 4 --- Discussion --- p.120 / Chapter General conclusions --- p.125
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_328525 |
| Date | January 2012 |
| Contributors | Xia, Tian., Chinese University of Hong Kong Graduate School. Division of Medical Sciences. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, bibliography |
| Format | electronic resource, electronic resource, remote, 1 online resource (xvi, 134 leaves) : ill. (some col.) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
Page generated in 0.0036 seconds