胰腺癌是一種死亡率極高的癌症, 據統計在所有的種族和性別中能達到五年存活的胰腺癌患者僅有5.5%。在現有醫學的治療方法中，除了手術切除之外，化學療法依然是主要的應對之策。接受胰腺癌切除術後的無瘤患者的生存期中位數和以現代一線化療藥吉西他濱治療的胰腺癌患者的生存期分別為13.4和6.9月。因此, 臨床上迫切需求更有效治療胰腺癌的新藥物。 / 我們從中藥鴉膽子中分離出了10種不同的化學單體。經過在人類胰腺癌細胞Capan-2上進行的細胞毒性篩選後, 發現Brucein D （BD）擁有最強的胰腺癌細胞毒性作用。我們目前的體外與體內實驗的目標是對BD可能具備的抗胰腺癌活性進行深入評估, 並進一步揭示其作用機理。 / 體外實驗研究表明BD可以極大程度上抑制Capan-2細胞生長, 同時對於人類肝細胞WRL68和人類胰腺幹細胞PPC僅存在很輕微的毒性作用。BD的抑制細胞生長作用和喜樹堿相當, 但顯著強於一線抗胰腺癌藥吉西他濱作。實驗中我們發現在BD作用的Capan-2細胞的線粒體膜電位被減弱, 其減弱程度與BD的濃度存在一定的劑量依賴性。另外, 被BD處理後的Capan-2細胞中的Bcl-2表達減弱, 與此同時capase 9和caspase 3的表達呈顯著性加強。除此之外, BD可以導致基因DNA破碎, 增加Capan-2細胞處於細胞凋亡期的數量, 而且處於凋亡期細胞的數量與BD存在劑量依賴性。 / 我們建立起原位型胰腺癌裸鼠模型並利用其進行體內實驗研究。研究結果顯示, BD治療組裸鼠的存活率遠遠大於吉西他濱治療組。此外, 與磷酸鹽緩衝鹽水注射組比較, BD治療組可以極大程度的減輕腫瘤的重量和減小腫瘤的體積。與此同時, 血液生化分析結果表明BD可以明顯降低CA19-9在血液中的表達。螢光免疫檢驗法結果揭示BD能夠調低CA19-9和Ki-67在胰腺腫瘤組織中的表達。蛋白質印記分析的結果也顯示BD治療後可以增強胰腺腫瘤組織中caspase 3, 8, 9的表達, 而減弱IKKα和NF-κB p65的表達。另外, 通過ELISA分析後顯示, BD治療明顯降低了NF-κB p65在細胞質與細胞核中的表達, 其表達程度與BD的濃度成反比。 / 綜上所述, 我們目前的體外和體內研究表明, BD作為一種存在于天然中藥中的化學單體具有很好的抗胰腺癌的潛質, 值得進一步研究和開發, 使之成為臨床治療胰腺癌的一種安全有效的新藥物。 / Pancreatic adenocarcinoma has a high morbidity and mortality rate in cancers as it possesses only 5.5% of 5-year survival rate for all races and both sexes. The median disease-free survival following complete resection of the pancreatic tumor and adjuvant chemotherapy with the first-line chemotherapeutic agent gemcitabine is 13.4 and 6.9 months, respectively. There issued an urgent need for alternative effective agents to producing a better clinical outcome for the management of this deadly disease. / Previous studies in our research group have shown that the fruit of Brucea javanica L. exhibited potent anti-pancreatic cancer activity. In the current project, ten chemical compounds were isolated from this Chinese herb and screened for their cytotoxicity against cultured Capan-2 cells, a human pancreatic adenocarcinoma cell line. Among these compounds, Brucein D (BD) exhibited the most potent cytotoxic activity. Further in vitro and in vivo studies were conducted to evaluate the potential anti-pancreatic cancer activity of BD and elucidate its underlying mechanisms of action. / In the In vitro study, BD was found to significantly inhibit the growth of Capan-2 cells, while exerting only modest cytotoxicity on human hepatocyte WRL68 cells and human pancreatic progenitor PPC cells. The anti-proliferative effects of BD were comparable to those exhibited by camptothecin and gemcitabine. We found a dose-dependent decrease of the mitochondrial membrane potential in BD-treated Capan-2 cells. In addition, BD exposure was able to attenuate the expression of Bcl-2 and significantly accentuate the expression of both caspase 9 and caspase 3. Moreover, BD was capable of inducing the fragmentation of genomic DNA while increasing the percentage of Capan-2 cells in the apoptotic phase and the quantity of apoptosis cells was observed in a dose- dependent manner. / A mouse model of orthotopic pancreatic cancer was established for the in vivo experiments. The results demonstrated that the BD-treated groups had a higher survival rate than that the gemcitabine-treated groups. Moreover, it was found that BD treatments significantly reduced the tumor weight and volume when compared with those of PBS injected group. Meanwhile, blood biochemistry analyses showed that BD significantly decreased the expression of CA19-9 (a tumor mark). Immunofluorescence study also revealed that BD could down-regulate the expression of both CA19-9 and Ki-67 in pancreatic tumor tissues. Furthermore, Western blot analysis showed that BD treatments could accentuate the expression of caspases 3, 8, 9 and decreased the expression of IKKα and NF-κB p65 in total. Moreover, BD attenuated the expression of NF-κB p65 in both cytoplasmic and nuclear factions of the tumor tissues as detected by ELISA kit, and the expression rate was inversely proportional to the doses of BD used. / Taken these data together, our in vitro and in vivo studies have successfully demonstrated that BD, a naturally occurring chemical compound from Fructus Bruceae, is a promising anti-pancreatic cancer agent worthy of further development into pharmaceutical agent for pancreatic cancer. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Liu, Ling. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 217-253). / Abstracts also in Chinese. / ABSTRACT --- p.I / 摘要 --- p.IV / PUBLICATIONS --- p.VI / ACKNOWLEDGEMENTS --- p.X / TABLE OF CONTENTS --- p.XI / LIST OF FIGURES --- p.XIX / LIST OF TABLES --- p.XXIII / LIST OF ABBREVIATIONS --- p.XXV / Chapter CHAPTER 1 --- GENERAL INTRODUCTION / Chapter 1.1 --- Pancreas --- p.2 / Chapter 1.1.1 --- Gross anatomy --- p.2 / Chapter 1.1.2 --- Microscopic anatomy --- p.5 / Chapter 1.1.2.1 --- Acini cells --- p.7 / Chapter 1.1.2.2 --- Duct cells --- p.7 / Chapter 1.1.2.3 --- Stroma --- p.14 / Chapter 1.1.2.4 --- Islets cells --- p.15 / Chapter 1.1.3 --- Pancreatic diseases --- p.16 / Chapter 1.2 --- Pancreatic Cancer --- p.30 / Chapter 1.2.1 --- Epidemiology --- p.30 / Chapter 1.2.2 --- Risk factors --- p.32 / Chapter 1.2.3 --- Clinical symptoms, diagnosis and staging --- p.34 / Chapter 1.2.4 --- Types of pancreas tumor --- p.42 / Chapter 1.3 --- Treatment of Pancreatic Cancer --- p.47 / Chapter 1.3.1 --- Treatment for localized disease --- p.49 / Chapter 1.3.2 --- Treatment for locally advanced disease --- p.50 / Chapter 1.3.3 --- Treatment for metastatic disease --- p.52 / Chapter 1.4 --- Molecular Targets for Pancreatic Cancer Therapy --- p.56 / Chapter 1.4.1 --- Mechanisms of apoptosis --- p.56 / Chapter 1.4.2 --- Roles of mitochondrial pathway in apoptosis --- p.58 / Chapter 1.4.3 --- NF-κB activation on cancers --- p.59 / Chapter 1.4.4 --- CA19-9 as a therapeutic target for Pancreatic Cancer --- p.62 / Chapter 1.4.5 --- Ki-67 is associated with for cellular proliferation --- p.64 / Chapter 1.5 --- Applications of Chinese Medicine in Cancer Treatment --- p.66 / Chapter 1.5.1 --- Background of traditional Chinese medicine --- p.66 / Chapter 1.5.2 --- Chinese medicine herbs commonly used for cancer treatment --- p.67 / Chapter 1.6 --- Mouse Models of Pancreatic Cancer --- p.75 / Chapter 1.6.1 --- Anatomy of pancreas in mouse --- p.75 / Chapter 1.6.2 --- Pancreatic cancer models --- p.77 / Chapter 1.7 --- Hypothesis and Objectives of the Study --- p.83 / Chapter CHAPTER 2 --- ANTI-PANCREATIC CANCER EFFECTS OF TEN CHEMICAL COMPOUNDS DERIVED FROM FRUCTUS BRUCEAE ON CULTURED CAPAN-2 CELLS / Chapter 2.1 --- Introduction --- p.86 / Chapter 2.1.1 --- Brucea javanica L. Merr --- p.86 / Chapter 2.1.2 --- The fruit of Brucea javanica --- p.88 / Chapter 2.1.3 --- Used of Fructus Bruceae to treat cancers by Chinese medicine practitioners --- p.90 / Chapter 2.1.4 --- Biological activities of some chemical compounds from Brucea javanica --- p.90 / Chapter 2.1.5 --- Chemical structure of ten compounds isolated from Fructus Bruceae --- p.92 / Chapter 2.2 --- Materials and Methods --- p.96 / Chapter 2.2.1 --- Plant material --- p.96 / Chapter 2.2.2 --- Extratcion, fractionation, isolate and characterization --- p.96 / Chapter 2.2.3 --- General procedures on structural elucidation and phytochemical work --- p.100 / Chapter 2.2.4 --- Preparation of solutions of tern chemical compounds derived from Fructus Bruceae --- p.101 / Chapter 2.2.5 --- General cell culture methods --- p.101 / Chapter 2.2.6 --- Selection of appropriate seeding density of Capan-2 cells --- p.102 / Chapter 2.2.7 --- Cytotoxicity evaluation by SRB assay --- p.102 / Chapter 2.2.8 --- Statistical analyses --- p.103 / Chapter 2.3 --- Results --- p.105 / Chapter 2.3.1 --- Seletion of appropriate seeding density of Capan-2 cells --- p.105 / Chapter 2.3.2 --- IC₅₀ values of ten tested compounds and chemical structures --- p.107 / Chapter 2.4 --- Discussion --- p.111 / Chapter CHAPTER 3 --- INVOLVEMENT OF THE MITOCHONDRIAL PATHWAY IN BRUCEIN D-INDUCED APOPTOSIS IN CAPAN-2 CELLS / Chapter 3.1 --- Introduction --- p.116 / Chapter 3.2 --- Materials and Methods --- p.117 / Chapter 3.2.1 --- General cell culture --- p.117 / Chapter 3.2.2 --- Cytotoxicity assay --- p.119 / Chapter 3.2.3 --- Proliferation assay --- p.120 / Chapter 3.2.4 --- Hoechest fluorescence staining for morphological evaluation --- p.121 / Chapter 3.2.5 --- Cell cycle analysis by flow cytometry --- p.122 / Chapter 3.2.6 --- Quantitative analysis of apoptosis by Annexin V-PI staining assay --- p.122 / Chapter 3.2.7 --- Estimation of the changes of MMP on BD-treated Capan-2 cells --- p.123 / Chapter 3.2.8 --- Western blot analysis --- p.124 / Chapter 3.2.9 --- Statistical analyses --- p.125 / Chapter 3.3 --- Results --- p.126 / Chapter 3.3.1 --- BD significantly inhibited the proliferation of Capan-2 cells --- p.126 / Chapter 3.3.2 --- BD was less cytotoxic on cultured WRL68 and PPC cells than that of controls --- p.128 / Chapter 3.3.3 --- BD induced DNA condensation in Capan-2 cells --- p.131 / Chapter 3.3.4 --- BD induced an increase in the percentage of subG1 phase (apoptotic cells) --- p.133 / Chapter 3.3.5 --- BD dose-dependently induced cellular apoptosis to Capan-2 cells --- p.136 / Chapter 3.3.6 --- The MMP of Capan-2 cells were significantly attenuated by BD treatment --- p.139 / Chapter 3.3.7 --- BD increased the expression of apoptotic caspases in Capan-2 cells --- p.142 / Chapter 3.4 --- Discussion --- p.144 / Chapter CHAPTER 4 --- BRUCEIN D SUPPRESSES PANCREATIC TUMOR GROWTH IN AN ORTHOTOPIC MOUSE MODEL THROUGH THE CASPASE 3, 8, 9 AND NF-κB PATHWAYS / Chapter 4.1 --- Introduction --- p.150 / Chapter 4.2 --- Materials and Methods --- p.153 / Chapter 4.2.1 --- Ethics statement and animal holdings --- p.153 / Chapter 4.2.2 --- Cell culture --- p.153 / Chapter 4.2.3 --- Establishment of an orthotopic pancreatic cancer mouse model --- p.154 / Chapter 4.2.4 --- Treatment of orthotopic pancreatic cancer mice with BD --- p.155 / Chapter 4.2.5 --- Necropsy procedure and histological studies --- p.156 / Chapter 4.2.6 --- Hematoxylin-eosin staining --- p.156 / Chapter 4.2.7 --- Determination of CA19-9 and Ki-67 by immunofluorescence staining --- p.160 / Chapter 4.2.8 --- CA 19-9 expression in blood --- p.161 / Chapter 4.2.9 --- Western blot analysis of Caspase 3,8,9, IKKα and NF-κB p65 --- p.162 / Chapter 4.2.10 --- Extraction of the nucleus and cytoplasm from pancreatic tumor tissues --- p.163 / Chapter 4.2.11 --- Detection of the expression of NF-κB p65 in both cytoplasm and nuclear parts of pancreatic cancer cells --- p.165 / Chapter 4.2.12 --- Statistical analyses --- p.166 / Chapter 4.3 --- Results --- p.167 / Chapter 4.3.1 --- BD treatment enhanced the survival rate of tumor-bearing mice and significantly attenuated the tumor weight and volume --- p.167 / Chapter 4.3.2 --- Histological evaluation of the pancreas and pancreatic tumor after BD treatment --- p.175 / Chapter 4.3.3 --- BD significantly decreased the expression of CA19-9 in the blood samples of the experimental mice --- p.178 / Chapter 4.3.4 --- BD down regulated the expression of CA19-9 in pancreatic tumor tissues --- p.180 / Chapter 4.3.5 --- BD down regulated the expression of Ki-67 in pancreatic tumor tissues --- p.183 / Chapter 4.3.6 --- BD accentuated the expression of Caspase3, 8, 9 and decreased the expression of NF-κB p65 --- p.186 / Chapter 4.3.7 --- BD decreased the expression of NF-κB p65 in both cytoplasm and nucleus of pancreatic tumor cells --- p.189 / Chapter 4.4 --- Discussion --- p.191 / Chapter CHAPTER 5 --- GENERAL DISCUSSION, CONCLUSIONS AND FUTURE STUDIES / Chapter 5.1 --- General Discussion --- p.200 / Chapter 5.2 --- General Conclusions --- p.209 / Chapter 5.3 --- Limitation of Study --- p.211 / Chapter 5.4 --- Clinical Significance of Study Results --- p.212 / Chapter 5.5 --- Future Studies --- p.214 / Chapter 5.5.1 --- Investigation of the possible synergistic effect of combination of BD with gemcitabine on orthotopic pancreatic cancer mouse model --- p.214 / Chapter 5.5.2 --- Testing BD on different animal models --- p.215 / REFERENCES / References by Alphabetical Order --- p.217

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

Cheung, Ka Yan. / "Aug 2010." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 157-167). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgments --- p.v / Table of Contents --- p.vi / List of Figures --- p.x / List of Tables --- p.xi / Abbreviations --- p.xii / Chapter Chapter1 --- General Introduction --- p.1 / Chapter 1.1 --- Cancer epidemiology and managements --- p.2 / Chapter 1.2 --- Photodynamic therapy (PDT) as cancer treatment --- p.7 / Chapter 1.3 --- Pheophorbide a (Pa) as a photosensitizer for PDT --- p.13 / Chapter 1.4 --- Aim of study --- p.15 / Chapter Chapter2 --- The anti-proliferative effect of pheophorbide a- mediated photodynamic therapy on human breast adenocarcinoma cell line MCF-7 --- p.17 / Chapter 2.1 --- Introduction / Chapter 2.1.1 --- Cell cycle regulation --- p.18 / Chapter 2.1.2 --- Growth arrest and DNA damage inducible (GADD) genes as cell cycle regulators --- p.22 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Materials / Chapter 2.2.1.1 --- Cell line --- p.29 / Chapter 2.2.1.2 --- "Cell culture medium, supplements and other reagents" --- p.29 / Chapter 2.2.1.3 --- Gene expression assay reagents --- p.30 / Chapter 2.2.1.4 --- Reagents and buffers for Western blotting --- p.32 / Chapter 2.2.1.5 --- Cell cycle analysis reagents --- p.35 / Chapter 2.2.2 --- Methods / Chapter 2.2.2.1 --- Cell line propagation and subculture --- p.36 / Chapter 2.2.2.2 --- Whole-transcript expression micro array analysis --- p.37 / Chapter 2.2.2.3 --- GADD genes expression assay- RT-PCR --- p.37 / Chapter 2.2.2.4 --- Cell cycle analysis --- p.40 / Chapter 2.2.2.5 --- Western Blotting --- p.41 / Chapter 2.2.2.6 --- Statistical analysis --- p.43 / Chapter 2.3 --- Results / Chapter 2.3.1 --- Effect of Pa-PDT on GADD genes expression by whole-transcript expression microarray analysis --- p.44 / Chapter 2.3.2 --- Effect of Pa-PDT on GADD genes expression by RT-PCR --- p.46 / Chapter 2.3.3 --- Temporal change in the cell cycle profile after Pa-PDT --- p.48 / Chapter 2.3.4 --- Effect of Pa-PDT on cell cycle associated proteins --- p.65 / Chapter 2.4 --- Discussion --- p.67 / Chapter Chapter3 --- Development of drug resistance in human breast adenocarcinoma cell line MDA and the circumvention by pheophorbide a-mediated photodynamic therapy --- p.77 / Chapter 3.1 --- Introduction / Chapter 3.1.1 --- Clinical Importance of multidrug resistance (MDR) --- p.78 / Chapter 3.1.2 --- Mechanisms of MDR --- p.78 / Chapter 3.1.3 --- Development of MDR cell lines --- p.82 / Chapter 3.1.4 --- Reversal of MDR by P-glycoprotein modulators --- p.83 / Chapter 3.1.5 --- Therapeutic potential of Pa-PDT in treating MDR cancers --- p.83 / Chapter 3.2 --- Materials and Methods / Chapter 3.2.1 --- Materials / Chapter 3.2.1.1 --- Cell line --- p.85 / Chapter 3.2.1.2 --- "Cell culture medium, supplements and other reagents" --- p.85 / Chapter 3.2.1.3 --- Cell viability assay reagents --- p.85 / Chapter 3.2.1.4 --- Gene expression assay reagents --- p.86 / Chapter 3.2.2 --- Methods / Chapter 3.2.2.1 --- Cell line propagation and subculture --- p.87 / Chapter 3.2.2.2 --- Drug-resistance development --- p.88 / Chapter 3.2.2.3 --- Measurement of cell viability - MTT reduction assay --- p.88 / Chapter 3.2.2.4 --- ABCB1 expression assay- RT-PCR --- p.89 / Chapter 3.2.2.5 --- Doxorubicin uptake assay --- p.91 / Chapter 3.2.2.6 --- Pheophorbide a uptake assay --- p.91 / Chapter 3.2.2.7 --- Statistical analysis --- p.92 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Cytotoxicity of doxorubicin on MDA and MDA-R cells --- p.93 / Chapter 3.3.2 --- mRNA expression of ABCB1 (P-glycoprotein) in MDA and MDA-R cells --- p.96 / Chapter 3.3.3 --- Doxorubicin uptake by MDA and MDA-R cells --- p.98 / Chapter 3.3.4 --- Circumvention of drug resistance in MDA-R cells by Pa-PDT --- p.102 / Chapter 3.3.5 --- Pheophorbide a uptake by MDA and MDA-R cells --- p.104 / Chapter 3.4 --- Discussion --- p.106 / Chapter Chapter4 --- Synergistic anti-proliferation of pheophorbide a-mediated photodynamic therapy and doxorubicin on multidrug resistant uterine sarcoma cell line Dx5 --- p.113 / Chapter 4.1 --- Introduction / Chapter 4.1.1 --- Clinical limitations of doxorubicin as chemotherapeutic drug --- p.114 / Chapter 4.1.2 --- Clinical limitations of photodynamic therapy --- p.115 / Chapter 4.1.3 --- Combination therapy with Dox and Pa-PDT --- p.117 / Chapter 4.1.4 --- Uterine sarcoma cell line Dx5 as in vitro model for combination therapy --- p.118 / Chapter 4.2 --- Materials and Methods / Chapter 4.2.1 --- Materials / Chapter 4.2.1.1 --- Cell line --- p.120 / Chapter 4.2.1.2 --- "Cell culture medium, supplements and other reagents" --- p.120 / Chapter 4.2.1.3 --- Anti-cancer drugs --- p.121 / Chapter 4.2.1.4 --- "ROS inhibitor, α-tocopherol" --- p.121 / Chapter 4.2.1.5 --- Cell viability assay reagents --- p.122 / Chapter 4.2.1.6 --- P-glycoprotein activity assay reagents --- p.122 / Chapter 4.2.2 --- Methods - / Chapter 4.2.2.1 --- Cell line propagation and subculture --- p.123 / Chapter 4.2.2.2 --- Cell viability assay --- p.123 / Chapter 4.2.2.3 --- P-glycoprotein activity assay --- p.124 / Chapter 4.2.2.4 --- Statistical analysis --- p.125 / Chapter 4.3 --- Results / Chapter 4.3.1 --- Combination therapy of Pa-PDT and doxorubicin in Dx5 cells --- p.126 / Chapter 4.3.2 --- Effect of α-tocopherol on the synergism between Pa-PDT and doxorubicin in Dx5 cells --- p.129 / Chapter 4.3.3 --- Effect of Pa-PDT on P-glycoprotein activity in Dx5 cells --- p.132 / Chapter 4.3.4 --- Combination therapy of Pa-PDT and doxorubicin in SA cells --- p.138 / Chapter 4.4 --- Discussion --- p.141 / Chapter Chapter5 --- General Discussion --- p.148 / Chapter 5.1 --- Pa-PDT induced growth arrest and DNA fragmentation in breast cancer MCF-7 cells --- p.149 / Chapter 5.2 --- Circumvention of doxorubicin resistance by Pa-PDT in breast cancer MDA cells --- p.151 / Chapter 5.3 --- Synergistic anti-proliferation of Pa-PDT and doxorubicin on uterine sarcoma cell line Dx5 --- p.151 / Chapter 5.4 --- Clinical implication --- p.153 / Chapter 5.5 --- Conclusions and future perspectives --- p.153 / References --- p.157

Yuen, Ka Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 95-104). / Abstracts in English and Chinese. / Chapter 1 --- Introduction / Chapter 1.1 --- CANCER / Chapter 1.1.1 --- OVERVIEW OF CANCER --- p.1 / Chapter 1.1.2 --- DEVELOPMENT OF CANCER --- p.1 / Chapter 1.1.3 --- CHARACTERISTICS OF CANCER CELLS --- p.3 / Chapter 1.1.4 --- CATEGORIZATION OF CANCER --- p.6 / Chapter 1.1.5 --- RISK FACTORS IN CANCER DEVELOPMENT --- p.7 / Chapter 1.1.6 --- EPIDEMIOLOGY OF CANCER --- p.11 / Chapter 1.1.7 --- CANCER THERAPIES --- p.13 / Chapter 1.2 --- SOYBEANS AND ISOFLAVONES / Chapter 1.2.1 --- GENERAL INTRODUCTION OF ISOFLAVONES --- p.18 / Chapter 1.2.2 --- NATURAL FUNCTIONS OF ISOFLAVONES --- p.19 / Chapter 1.2.3 --- STRUCTURES OF ISOFLAVONES --- p.19 / Chapter 1.2.4 --- BIOACTIVITIES OF SOY ISOFLAVONES --- p.20 / Chapter 1.2.5 --- PRODUCTION OF SOY ISOFLAVONES CAN BE AFFECTED BY MANY FACTORS --- p.21 / Chapter 1.3 --- THE AIM AND OBJECTIVES OF THE PROJECT / Chapter 1.3.1 --- AIM OF THE PROJECT --- p.22 / Chapter 1.3.2 --- OBJECTIVES OF THE PROJECT --- p.23 / Chapter 2 --- Materials / Chapter 2.1 --- 19 DROUGHT TOLERANT SOYBEAN LINES --- p.24 / Chapter 2.2 --- 5 HUMAN CANCER CELL LINES --- p.25 / Chapter 2.3 --- CHEMICALS --- p.25 / Chapter 2.4 --- REAGENTS --- p.26 / Chapter 2.5 --- SOLUTIONS --- p.26 / Chapter 2.6 --- MAJOR EQUIPMENTS AND MATERIALS --- p.28 / Chapter 3 --- Methodology / Chapter 3.1 --- PREPARATION OF SOYBEAN EXTRACTS --- p.29 / Chapter 3.2 --- HIGH PERFORMANCE LIQUID CHROMATOGRAPHY(HPLC) ANALYSIS OF SOYBEAN EXTRACTS / Chapter 3.2.1 --- PREPARATION OF SOYBEAN EXTRACTS FOR HPLC ANALYS --- p.30 / Chapter 3.2.2 --- HPLC ANALYSIS --- p.30 / Chapter 3.3 --- PREPARATION OF 5 HUMAN CANCER CELL LINES FOR ANTI-PROLIFERATION ASSAY / Chapter 3.3.1 --- THAWING OF THE C Y R O P R E S E R V E D CELL LINES --- p.31 / Chapter 3.3.2 --- MAINTAINING OF CELL LINES --- p.32 / Chapter 3.3.3 --- ANTI-PROLIFERATION TEST WITH MTT ASSAY --- p.33 / Chapter 3.4 --- STATISTICS --- p.35 / Chapter 4 --- Results / Chapter 4.1 --- PREPARARTION OF SOYBEAN EXTRACTS --- p.36 / Chapter 4.2 --- HPLC ANALYSIS OF 5 SELECTED ISOFLAVONES IN 19 SOYBEAN SAMPLES --- p.36 / Chapter 4.3 --- COMPARISON OF SUM OF 5 SELECTED ISOFLAVONES FROM THE PARENT SOYBEAN AND VARIETIES HARVESTED FROM IRRIGATED LAND --- p.43 / Chapter 4.4 --- COMPARISON OF SUM OF 5 SELECTED ISOFLAVONES FROM THE SOYBEAN VARIETIES HARVESTED FROM DROUGHT LAND --- p.45 / Chapter 4.5 --- COMPARISON OF SELECTED ISOFLAVONES FROM THE PARENT SOYBEAN AND VARIETIES HARVESTED FROM IRRIGATED LAND --- p.47 / Chapter 4.6 --- COMPARISON OF SELECTED ISOFLAVONES FROM THE PARENT SOYBEAN AND VARIETIES HARVESTED FROM DAROUGHT LAND --- p.54 / Chapter 4.7 --- COMPARISON OF SUM OF SELECTED ISOFLAVONES AMONG THE SOYBEANS HARVESTED FROM IRRIGATED LAND AND DROUGHT LAND --- p.59 / Chapter 4.8 --- DETERMINATION OF ANTI-PROLIFERATION ABILITIES OF SOYBEAN SAMPLES --- p.19 / Chapter 4.8.1 --- ANTI-PROLIFERATION TEST OF ETHANOL AND 2-PHEN YLCHROMONE --- p.61 / Chapter 4.8.2 --- ANTI-PROLIFERATION ACTIVITIES OF 19 SOYBEAN SAMPLES ON 5 HUMAN CANCER CELL LINES --- p.61 / Chapter 4.9 --- COMPARISON OF ANTI-PROLIFERATION POTENCIES OF19 SOYBEAN SAMPLES WITH SUM OF SELECTED ISOFLAVONES --- p.70 / Chapter 4.10 --- COMPARISON OF ANTI-PROLIFERATION POTENCIES OF19 SOYBEAN SAMPLES --- p.72 / Chapter 4.11 --- ANTI-PROLIFERATION EFFECT OF INDIVIDUAL ISOFLAVONES ON FIVE CANCER CELL LINES --- p.74 / Chapter 5 --- Discussion / Chapter 5.1 --- EXTRACTION OF 19 SOYBEAN LINES --- p.77 / Chapter 5.2 --- DETERMINATION OF QUANTITIES OF SELECTED ISOFLAVONES IN 19 SOYBEAN SAMPLES BY HPLC ANALYSIS --- p.77 / Chapter 5.3 --- COMPARISON OF SELECTED ISOFLAVONES AMONG 19 SOYBEAN SAMPLES / Chapter 5.3.1 --- COMPARISON OF SUM OF SELECTED ISOFLAVONES BETWEEN PARENT AND SOYBEANS HARVESTED FROM IRRIGATED LAND --- p.80 / Chapter 5.3.2 --- COMPARISON OF SUM OF SELECTED ISOFLAVONES BETWEEN SOYBEANS HARVESTED FROM DROUGHT LAND --- p.81 / Chapter 5.3.3 --- COMPARISON OF SELECTED ISOFLAVONES BETWEEN SOYBEANS HARVESTED FROM IRRIGATED LAND --- p.81 / Chapter 5.3.4 --- COMPARISON OF SELECTED ISOFLAVONES BETWEEN SOYBEANS HARVESTED FROM DROUGHT LAND --- p.82 / Chapter 5.3.5 --- COMPARISON OF SUM OF SELECTED ISOFLAVONES BETWEEN SOYBEANS HARVESTED FROM IRRIGATED LAND AND DROUGHT LAND --- p.83 / Chapter 5.4 --- COMPARISON OF ANTI-PROLIFERATION ACTIVITIES OF 19 SOYBEAN SAMPLES / Chapter 5.4.1 --- COMPARISON OF ANTI-PROLIFERATION ACTIVITIES OF19 SOYBEAN SAMPLES AMONG 5 CANCER CELL LINES --- p.84 / Chapter 5.4.2 --- COMPARISON OF ANTI-PROLIFERATION POTENCIES OF19 SOYBEAN SAMPLES --- p.85 / Chapter 5.4.3 --- COMPARISON OF ANTI-PROLIFERATION ACTIVITIES OF19 SOYBEAN SAMPLES AND CORRESPONDING SUM OF SELECTED ISOFLAVONES --- p.86 / Chapter 5.4.4 --- COMPARISON OF IC50S FROM SOYBEANS HARVESTED FROM IRRIGATED LAND AND DROUGHT LAND --- p.87 / Chapter 5.4.5 --- CORRELATION OF ISOFLAVONES AND ANTI-PROLIFERATION POTENCIES --- p.88 / Chapter 6 --- Conclusion --- p.90 / Chapter 7 --- References --- p.91 / Chapter 8 --- Appendix --- p.S1

Choi, Mei Yuk. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 79-89). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / Abstract (Chinese) --- p.v / List of Abbreviations --- p.vii / List of Figures --- p.viii / Chapter Chapter 1 --- Introduction / Chapter 1.1. --- General introduction of cancer --- p.1 / Chapter 1.2. --- Overview of apoptosis --- p.2 / Chapter 1.2.1. --- The extrinsic death receptor pathway --- p.4 / Chapter 1.2.2. --- The intrinsic mitochondrial pathway --- p.4 / Chapter 1.2.3. --- Cross-talk between the intrinsic and extrinsic pathways --- p.5 / Chapter 1.3. --- Overview of selenium --- p.6 / Chapter 1.3.1. --- Selenium and prostate cancer --- p.7 / Chapter i. --- Epidemiological studies --- p.7 / Chapter ii. --- Clinical trials --- p.8 / Chapter iii. --- Preclinical investigations --- p.10 / Chapter a. --- in vivo studies --- p.11 / Chapter b. --- in vitro studies --- p.12 / Chapter c. --- selenocystine and prostate cancer --- p.13 / Chapter 1.4. --- Objective --- p.15 / Chapter Chapter 2 --- Materials and methods / Chapter 2.1. --- Materials --- p.18 / Chapter 2.2. --- Methods --- p.19 / Chapter 2.2.1. --- Cell culture --- p.19 / Chapter 2.2.2. --- MTT assay --- p.19 / Chapter 2.2.3. --- Cell cycle distribution analysis --- p.20 / Chapter 2.2.4. --- TUNEL assay and DAPI staining --- p.20 / Chapter 2.2.5. --- Evaluation of mitochondrial membrane potential (ΔΨm) --- p.21 / Chapter 2.2.6. --- Measurement of superoxide generation (DHE assay) --- p.22 / Chapter 2.2.7. --- Inhibition of superoxide generation --- p.22 / Chapter 2.2.8. --- Western blot analysis --- p.23 / Chapter 2.2.9. --- Statistical analysis --- p.24 / Chapter Chapter 3 --- Results / Chapter 3.1. --- The antiproliferatvie effect of SeC on LNCaP and PC-3 cells --- p.25 / Chapter 3.2. --- The role of caspases in SeC-induced apoptosis --- p.34 / Chapter 3.3. --- The effect of SeC on the mitochondrial membrane potential --- p.39 / Chapter 3.4. --- The involvement of p53 in SeC-treated LNCaP cells --- p.44 / Chapter 3.5. --- MAPK and PI3K/Akt signaling pathways --- p.47 / Chapter 3.6. --- The role of superoxide in SeC-induced apoptosis --- p.52 / Chapter Chapter 4 --- Discussion --- p.62 / Chapter Chapter 5 --- Conclusion --- p.74 / References --- p.79

Amplification of the receptor tyrosine kinase ErbB-2 has been linked to the proliferation of breast cancer cells.1,2 Trastuzumab targets the extracellular domain of ErbB-2, leading to growth inhibition of approximately 15% of the breast cancers with genomic amplification of the ERBB2 gene.3 Clinical studies have demonstrated its efficacy in both early4 and metastatic breast cancers. 5,6 However, many tumors with ERBB2 amplification are not responsive to treatment.7 Moreover, the ones that initially respond, eventually progress and acquire drug resistance.8 An in vitro model for this acquired resistance was established by Chan & al.9 The breast cancer cell line, BT474, containing amplified ERBB2, was grown in the presence of trastuzumab for several months until subclones outgrew. Gene expression profiling was performed on these clones to determine differentially expressed genes between the parental and resistant cells. DARPP-32 (Dopamine and cAMP regulated phosphoprotein of 32kDa) was, by far, the most overexpressed transcript. DARPP-32 is coamplified with ERBB2 on the same amplicon of chromosome 17.10 This protein has been mostly described in neurobiology, but DARPP-32 overexpression was recently reported in gastrointestinal, esophageal, prostate and breast cancer.11 Therefore, we suggest that overexpression of DARPP-32 can cause acquired resistance of breast cancer cells to trastuzumab. The in vitro knockout of DARPP-32, using stable shRNA transfection, abolishes the resistance to trastuzumab in the clones, while overexpression of DARPP-32 in the parental cells results in de novo resistance. Overall, our results suggest that DARPP-32 may be a potential therapeutic target in breast cancer patients who develop acquired trastuzumab resistance.

Breast cancer is the most commonly diagnosed cancer in women. Despite recent advances in screening and early detection, breast cancer continues to result in a high incidence of morbidity and mortality. In its late stage the majority of patients exhibit signs of destructive skeletal metastasis. This complication is promoted by the production of growth factors by tumor cells which can induce tumor cell proliferation via their interaction with their respective receptors to initiate the vicious cycle of bone resorption. Inhibition of growth factors signaling through their receptors can therefore serve as a useful therapeutic approach to block bone metastasis. / The biological characteristics of cancer cells along with the targeting properties of immune system offer a novel approach in the treatment of breast cancer. Directed against HER-2/nue oncogene, the recombinant humanized monoclonal antibody, Trastuzumab (Herceptin), has shown significant clinical benefits for the treatment of HER-2 positive metastatic breast cancer. / In the present study, the effects of Herceptin and its molecular mechanism of action in abrogating the development and progression of osteolytic bone metastasis is investigated in an experimental mouse model of skeletal metastasis using human breast cancer cells BT-474 which are known to express high levels of HER-2. Treatment of BT-474 cells with Herceptin caused a dose dependent decrease in cell proliferation. In in vivo studies BT-474 cells were injected by into the left ventricle of female BALB/c nu/nu mice. Intraperitoneal infusion of Herceptin from the day of tumor cell inoculation or at the time of radiologically detectable skeletal metastasis either slowed the development or prevented the progression of skeletal metastasis as compared to control groups of animals receiving non-specific IgG. Bone histological analysis of long bones showed the ability of Herceptin to reduce the ratio of tumor volume to bone volume as well as mitotic index when Herceptin treatment was initiated from the day of tumor cell inoculation. Immunohistochemical analysis of long bones showed a significantly lower level of activated (phosphorylated) MAPK in bones of Herceptin treated animals. These studies demonstrate the ability of Herceptin to inhibit the development and abrogate the progression of skeletal metastasis associated with breast cancer by blocking the HER-2 mediated signaling pathways.

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O objetivo deste trabalho foi comparar o prognóstico de sobrevida da graduação histológica após efeito da quimioterapia (graus I versus II de Huvos), visando também identificar fatores prognósticos no que diz respeito à sobrevida livre de recidiva local (SLRL), sobrevida livre de metástase (SLM) e sobrevida global (SG), em pacientes portadores de osteossarcoma primário não metastático ao diagnóstico. Vinte e quatro entre 45 pacientes admitidos no Instituto de Ortopedia e Traumatologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo IOT/HC/FMUSP, entre 2000 e 2004, foram eleitos para o estudo, segundo os critérios de inclusão e exclusão utilizados. As probabilidades de sobrevida acumuladas foram feitas pela técnica de Kaplan-Meier e os índices I e II de HUVOS comparados pelos testes de Log Rank. A análise multivariada foi feita pela técnica de regressão logística com modelo de risco proporcional de COX e a validade estatística estabelecida para valores de p<0,05. Os graus I e II de Huvos, quando comparados, não foram considerados de valor prognóstico em nenhuma das sobrevidas estudadas (SLRL, SLM e SG). Os fatores adversos que influenciaram o risco de recidiva local e a sobrevida global, na análise univariada foram: subtipo histológico diferente do osteoblástico (p=0,017) e o tamanho tumoral maior que 15 cm (p=0,048). Em relação à SLM o subtipo não osteoblástico (p=0,007) teve um pior prognóstico. O subtipo histológico manteve sua significância na análise multivariada em todas as sobrevidas estudadas / The purpose of this study was to compare the prognostic of survivor of histologic graduation post chemotherapy (Huvos´s grade I versus II), aiming to identify prognostic factors concerning to local recurrence free survival (LRFS), metastases free survival (MFS) and overall survival (OS) in patients with nonmetastatic primary osteosarcoma. This study included 24 patients registred in the Instituto de Ortopedia e Traumatologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo - Brazil, from 2000 to 2004. Survivor rates were calculed using Kaplan-Meier method. Huvos´s grade (I e II) were compared using the Log Rank test. Cox proportional hazards model was used for multifatorial analysis. Statistical significance was defined as a p value less than 0, 05. The Huvos´s grade I versus II was not significant factor for LRFS, MFS or OS. The adverse factors for LRFS and OS in univariate analysis were nonosteoblastic histologic subtypes (p=0,017) and large tumor (p=0,048). For MFS nonosteoblastic histologic subtypes (p=0,007) had worse prognostic. The histologic subtypes maintained their significance in multivariate testing on all studied survivor