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1 UNIVERSITI PUTRA MALAYSIA EFFECTS OF CXCR4 SILENCING BY sirna ENGRAFTED CATIONIZED DEXTRAN IN MOUSE MODELS OF COLORECTAL CANCER AND LIVER METASTASIS FATEMEH ABEDINI IB

2 EFFECTS OF CXCR4 SILENCING BY sirna ENGRAFTED CATIONIZED DEXTRAN IN MOUSE MODELS OF COLORECTAL CANCER AND LIVER METASTASIS By FATEMEH ABEDINI Thesis Submitted to the School of Graduate Studies, Universiti Putra Malaysia in Fulfilment of the Requirements for the Degree of Doctor of Philosophy July 2011

3 DEDICATION This thesis is dedicated to the memory of my dear parents (Mohammad Abedini and Khadijeh Poorhady), my dear husband (Dr. Mohammad Ebrahimi) and my darling daughters (Niousha and Nadiya) for their endless support and continuous encouragement throughout the thesis work. ii

4 Abstract of thesis presented to the Senate of Universiti Putra Malaysia in fulfilment of the requirement for the degree of Doctor of Philosophy. EFFECTS OF CXCR4 SILENCING BY sirna ENGRAFTED CATIONIZED DEXTRAN IN MOUSE MODELS OF COLORECTAL CANCER AND LIVER METASTASIS By FATEMEH ABEDINI July 2011 Chairman: Professor Maznah Ismail, PhD Faculty: Institute of Bioscience Liver metastasis is the main cause of colorectal cancer related mortality. CXCR4 is necessary for the outgrowth of colon cancer micrometastasis. CXCR4 gene expression and serum total lactate dehydrogenase, creatine kinase and alkaline phosphatase levels are often increased in patients with colorectal cancer. RNA interference is a well recognized pathway involved in cellular defense against viral invasion and post transcriptional regulation. This technology has emerged as a promising new strategy for the study of functional genomics and drug target validation. It is currently being evaluated in clinical trials as a potential therapy for cancers. This study aims to evaluate the transfection efficiency of three biodegradable polymers as carriers for CXCR4 sirnai, II to treat liver metastasis from colorectal cancer in vitro on mouse colon cancer cells (CT26.WT) and human colon cancer cells (HT29) and in vivo balb/c mice. In this study, dextran spermine, pullulan spermine and dextran hexamine were used as non-viral vectors for in vitro iii

5 and in vivo CXCR4 sirnas. Characterization of the morphology, size and stability of CXCR4 sirnas cationized dextran were performed using transmission electron microscopy, particle sizer and zeta potential. CXCR4 expression in human colorectal cell line HT29 was measured by real-time reverse transcription PCR and immunocytochemistry. Cell proliferation assay, cell cycle analysis, acridine orange/propidium iodide staining and ultrastructural changes of cells using transmission electron microscopy were also studied as biological evaluations. Among three carriers studied, dextran spermine showed smallest size 99.25±4.3 nm with suitable zeta potential 34.15±1.55 mv. These findings were further supported by RT PCR that showed more silencing has been achieved by CXCR4 pool sirna/dextran spermine in comparison to pullulan spermine and dextran hexamine. The percentage of viability for dextran spermine was higher than pullulan spermine and dextran-hexamine. Animal study demonstrated that inhibition of CXCR4 gene with CXCR4 sirnai, II/dextran spermine was more efficient than naked CXCR4 sirnai, II and also post treatment follow transfection of tumor cells more efficient than just transfection cells treatment with naked CXCR4 sirnai, II or CXCR4 sirnai, II/dextran spermine.cxcr4 expression was correlated with serum total lactate dehydrogenase, alkaline phosphatase and creatine kinase. These data show that CXCR4 expression lactate dehydrogenase, alkaline phosphatase and creatine kinase may be useful markers to predict liver metastasis in colorectal cancer. Dextran spermine demonstrated improved transfection efficiency in sirna therapy. iv

6 Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia sebagai memenuhi keperluan untuk ijazah Doktor Falsfah KESAN PERENCATAN CXCR4 sirna PELEKAP DEXTRAN TERKATION PADA KANSER KOLORAKTEL DAN METASTASIS HATI DI DALAM MODEL TIKUS Pengerusi: Maznah Ismail, PhD Fakulti : Institute of Bioscience Oleh FATEMEH ABEDINI July, 2011 Metastasis hati adalah penyebab utama yang menyumbang kepada kanser koloraktel (CRC) yang boleh menyebabkan kematian. CXCR4 diperlukan untuk perkembangan kanser kolon metastasis mikro. Expresi gen CXCR4 dan serum total laktat dehidrogenase, kreatin kinase dan tahap alkalin fosfatase selalunya meningkat pada pesakit yang menghidapi kanser koloraktel. RNA interference (RNAi) adalah rantaian tindakbalas biokimia yang diperakui terlibat di dalam tindakbalas pertahanan selular terhadap serangan virus, pengembangan transposon dan regulasi pasca-transkripsi. Teknologi ini telah berkembang sebagai teknologi baru yang berpotensi sebagai strategi untuk sasaran validasi ubat dan kajian terhadap fungsi genomik, dan sedang dinilai di dalam percubaan klinikal sebagai terapi yang berpotensi untuk penyakit etiologi genetik. Kajian ini bertujuan untuk menilai keberkesanan transfeksi tiga polimer yang boleh diuraikan secara biologi sebagai pembawa CXCR4 sirna ke atas sel kanser koloraktel secara in vitro manakala v

7 metastasi hepatik telah dilancarkan dengan sel karsinoma kolon tikus CT26.WT pada tikus balb/c secara in vivo. Dalam kajian ini, polisakarida terkation seperti dekstranspermin, pullulan-spermin, dan dekstran-hexamin, telah digunakan sebagai vector bukan virus untuk CXCR4 sirna. Pencirian morfologi, saiz dan kestabilan dextran terkation-cxcr4 sirna (dekstran-spermin) telah dilakukan dengan menggunakan mikroskopi electron transmisi, portikel sizer dan potensi zeta. Ekspresi CXCR4 di dalam garisan sel kolorektal manusia HT29 telah diukur dengan menggunakan real time reverse transcription PCR dan immunocytochemistry. Asai proliferasi sel, analisis kitaran sel, pewarnaan acridine orange and propidium iodide dan perubahan saiz nanopartikel untuk kegunaan ke atas binatang dan manusia haruslah dalam skala nm dengan cas permukaan yang minimum. Dextran spermin menunjukkan saiz paling kecil (99.25±4.3 nm) di antara ketiga-tiga pembawa yang digunakan dalam kajian ini yang mana sesuai dengan keupayaan zeta 34.15±1.55 mv. Ini dibuktikan lagi melalui RT-PCR yang menunjukkan keputusan knock down yang lebih tinggi oleh CXCR4 sirnai, II/ dextran-spermine berbanding pullulan spermine dan dextran hexamine. Dextran spermin tidak mempengaruhi viabiliti sel pada 7.5 g/ml melalui asai viabiliti MTS. Kajian in vivo menunjukkan knock down CXCR4 sirnai, II/ dextran spermine lebih efisyen berbanding naked CXCR4 sirna dan rawatan susulan selepas pemindahan sel tumor adalah lebih efisyen berbanding hanya melalui rawatan pemindahan sel dengan naked CXCR4 sirna atau CXCR4. Kajian ini menunjukkan dekstran terkation telah meningkatkan tahap ekspresi relative CXCR4 sirna dalam sel HT29 secara signifikan berbanding CXCR4 sirna tanpa dekstran terkation, pullulan-spermin dan dekstran- vi

8 hexamine. Keberkesanan perencatan yang tinggi dengan kadar toksik yang rendah telah dicapai dengan menggunakan CXCR4 sirnas/dekstran-spermin, dan telah dibuktikan dengan ekspresi gen CXCR4 hati. Ekspresi CXCR4 adalah berkait-rapat dengan serum total LDH, CK, dan ALP enzym. Data ini menunjukkan CXCR4, LDH, CK dan ALP boleh dijodikan penunjuk untuk menentukan matastasis hati dalam kanser kolorektal. vii

9 ACKNOWLEDGEMENTS I would like to express my sincere appreciation and gratitude to my supervisor Prof. Dr. Maznah Ismail under whose guidance and supervision had provided me the opportunity and conductive environment to complete this study. Her invaluable constructive criticism and continuous support had built in me the confidence to undertake the laboratory investigations with patience and optimism throughout the course my studies. Special thanks go to the members of my supervisory committee Prof. Dr. Tengku Azmi, Prof. Dr. Abdul Rahman Omar, Associate Professor Dr. Chong Pei Pei and Associate Professor Dr. Hossein Hosseinkhani for their suggestions and useful deliberative discussions to make this study more comprehensive and meaningful. I would also like to thank Prof. Dr. Mohd Hair Bin Bejo for his invaluable advice and guidance on the histhopatology aspect of this investigation. I am equally indebted to Dr. Fatemeh Jahanshiri, Dr. Sahar Abasi, Dr. Mahdieh Jafari, Dr. Hassan Moini, Dr Farid Azizi, for their useful advice when dealing with specific problems. I am equally grateful to the staff of the Molecular lab and Microscopy Unit, Institute of Bioscience, especially Mr. Ho Oi Kuan and Ms Siti Muskinah for their kind assistance. I am immensely and forever grateful to those individuals who have, in one way or another provided me with the courage and resilience to pave the way towards the successful completion of this study. viii

10 I certify that a Thesis Examination Committee has met July 2011 to conduct the final examination of Fatemeh Abedini on her thesis entitled Effects of Silencing CXCR4 sirna Engrafted Cationized Dextran in Mouse Models of Colorectal Cancer and Liver Metastasis in accordance with the Universities and University Colleges Act 1971 and the constitution of the Universiti Putra Malaysia [P.U. (A) 106] 15 March The committee recommends that the student be awarded the Doctor of Philosophy. Members of the Examination Committee were as follows: SITI SHAPOR SIRAJ, PhD Professor Faculty of Agriculture Universiti Putra Malaysia (Chairman) ANNIE CHRISTIANUS, PhD Senior lecturer Faculty of Agriculture Universiti Putra Malaysia (Internal Examiner) SITI KHALIJAH DAUD, PhD Associate Professor Faculty of Science Universiti Putra Malaysia (Internal Examiner) CHRIS CARTER, PhD Professor of Aquaculture Nutrition Marine Research Laboratories, Taroona Australia (External Examiner) BUJANG BIN KIM HUAT, PhD Professor and Deputy Dean School of Graduate Studies Universiti Putra Malaysia Date: ix

11 This thesis was submitted to the Senate of Universiti Putra Malaysia and has been accepted as fulfilment of the requirement for the degree of Doctor of Philosophy. The members of the Supervisory Committee were as follows: Maznah Ismail, PhD Professor Faculty of Medicine and Health Sciences Universiti Putra Malaysia (Chairman) Tengku Azmi Ibrahim, PhD Associate Professor Faculty of Agriculture Universiti Putra Malaysia (Member) Abdul Rahman Omar, PhD Associate Professor Faculty of Veterinary Medicine Universiti Putra Malaysia (Member) Chong Pei Pei, PhD Associate Professor Faculty of Medicine and Health Sciences Universiti Putra Malaysia (Member) Hossein Hosseinkhani, PhD Associate Professor, National Yang-Ming University (Member) HASANAH MOHD GHAZALI, PhD Professor and Dean School of Graduate Studies University Putra Malaysia Date: x

12 DECLARATION I declare that the thesis is my original work except for quotations and citations which have been duly acknowledged. I also declare that it has not been previously, and is not concurrently, submitted for any other degree at Universiti Putra Malaysia or at any other institution. FATEMHE ABEDENI Date: xi

13 TABLE OF CONTENTS Page ABSTRACT... iii ABSTRAK... v ACKNOWLEDGEMENTS... viii APPROVAL... xi DECLARATION... xi LIST OF TABLES... xv LIST OF FIGURES... xvi LIST OF ABBREVIATIONS xix CHAPTER 1. INTRODUCTION Background General Objective Specific Objective LITERATURE REVIEW Colorectal Cancer Chemokines and Metastasis CXCR4 Chemokine (C-X-C motif) Receptor CXCR4 in Cancer RNA Interference Site of Conjugation and Chemical 21 Modification of sirna siRNA Conjugates for Targeted Delivery sirna Application sirna Application in Colorectal Cancer Gene Delivery and Approaches to Gene Therapy Viral Vector for Gene Delivery Nonviral Vector for Gene Delivery Transport through the Cytoplasm Pullulan Spermine, Dextran Spermine and Dextran Hexamine Carriers Physical Methods for Gene Delivery Serum CK, ALP and LDH Enzymes ENHANCEMENT OF IN VITRO sirna DELIVERY BY DIFFERENT CATIONIZED POLYSACCARIDES Introduction Materials xii

14 3.3 Methods Preparation of Polysaccharide-Oligoamine Conjugates MTS Assay in HT29 and CT26.WT Cell Line Lines Preparation and Characterization of CXCR4 Pool sirna/cationized Polysaccharide Nnoparticles RT-PCR and Real-time RT-PCR Analysis on HT29 Cells Immunocytochemistry Results Characterization of CXCR4 Pool sirna Cationized Polysaccharides Cell Viability in HT29 and CT26.WT cells RT-PCR and Real Time RT-PCR Analysis on 53 HT29 Cells Immunocytochemistry Analysis Discussion Conclusion CYTOTOXICITY EVALUATION OF DEXTRAN SPERMINE AS A TOOL FOR GENE THERAPY Introduction Materials Methods Serial Dilution of Dextran Spermine Toxicity 67 of MCF7 Cells CellProliferation Assay Cell Cycle Analysis Morphological and Characterization of Cells Acridine Orange and Propidium Iodid Staining Statistic Results Serial Dilution of Dextran Spermine Toxicity of MCF7 Cells Cell Proliferation Assay on HT29 and CT26WT Cell Lines Cell Cycle Analysis Transmission Electron Micrographs Analysis Fluorescence Micrographs Analysis Discussion Conclusion EVALUATION OF CXCR4 AND SERUM ENZYMES (LDH, ALPAND CK) LEVELS IN COLORECTAL CANCER USING NOVEl sirna DELIVERY SYSTEM xiii

15 5.1 Introduction Materials and Methods Materials Preparation and Characterization of a Nanoparticle Animal Expriments RNA Preparation and Real- Time RT-PCR Histostaining from Liver and Tumour Tissues Serum LHD, ALP and CK Enzymes Measurement Results Characterization of CXCR4 sirna/ Dextran Spermine Nanoparticles Real TimeRT-PCR of β-action and CXCR4 Expression Serum LDH, ALP and CK enzymes Measurements Hematoxylin & Eosin Staining of Tumor and Liver Tissue Discussion Conclusion SUMMERY AND GENERAL DISCUSSION CONCLUSION AND RECOMMENDATIONS FOR FUTUR RESEARCH REFERENCES APPENDIX 1: Mus Musculus Chemokine C-X-C motif Receptor APPENDIX 2: Mus Musculus βeta-actin mrna APPENDIX 3: Homo Sapiens Chemokine (C-X-X motif) Receptor 4 (CXCR4) APPENDIX 4: Homo Sapiens βeta- actin mrna Partical cds (Genbank EF ) APPENDIX 5: Serum LHD Level Among Group A, B, C, D, E and F APPENDIX 6: Serum ALP Level Among Group A, B, C, D, E and F APPENDIX 7: Serum CK Level Among Group A, B, C, D, E and F APPENDIX 8: Animal Ethics BIODATA OF STUDENT LIST OF PUBLICATIONS xiv