Biological screening of extracts of various bryophytes showed that the species Dicranum fulvum gave extracts with activity in both <u>in vitro</u> and <u>in vivo</u> bioassays. This plant was thus selected for extraction and fractionation, monitored by i<u>in vitro</u> bioassays. Isolation was guided by a combination of bioassay and chemical methods, and led to the isolation of three compounds, betulin, 9,l9- cyclolanostâ 23â eneâ 3,25â diol, and B-sitosterol. Purification was achieved by open column, flash column, gel filtration, thin layer chromatography, the chromatotron and crystallization. The isolated compounds were identified by comparisons of spectroscopic data with those of authentic samples and the matching of experimental and literature melting points and optical rotations. / Master of Science

Systemic chemotherapy is a major therapeutic approach for nearly all types and stages of cancer. Success of this treatment depends not only on the efficacy of the therapeutics but also on the transport of the drug to all tumor cells in sufficient concentrations. Intratumoral drug transport is limited by characteristics of the tumor microenvironment such as elevated interstitial pressure and sparse, irregular vascularization. Moreover, poor tumor selectivity, leads to systemic toxicity. Bacteria possess a host of characteristics that address the aforementioned challenges in conventional drug delivery approaches including tumor selectivity, preferential tumor colonization, effective tumor penetration, which can be augmented via genetic engineering. However, in clinical trials conducted to date, bacteria have rarely been able to inhibit tumor growth solely by their presence in the tumor. The overall goal of this doctoral dissertation is to develop a novel tumor treatment system based on Salmonella Typhimurium VNP20009 (genetically modified for preferential tumor colonization and attenuation) coupled with biodegradable copolymer, poly(lactic-co-glycolic acid) nanoparticles, hereafter referred to as NanoBEADS (Nanoscale Bacteria Enabled Autonomous Drug Delivery System). To this end, a NanoBEADS fabrication procedure that is robust and repeatable was established and a microfluidic chemotaxis-based sorting platform for the separation NanoBEADS from unattached nanoparticles was developed. The transport efficacy of NanoBEADS compared to the commonly used passively-diffusing nanoparticle was investigated in vitro and in vivo and the intratumoral penetration of the therapeutic vectors was quantified using a custom image processing algorithm. The mechanism of intratumoral penetration was elucidated through 2D and 3D invasion assays. Lastly, we developed a biophysical model of intratumoral transport of NanoBEADS based on the intratumoral penetration experimental results towards the theoretical evaluation of the drug transport profile following the administration of NanoBEADS. / PHD

Modifications of the potent anticancer agent taxol were carried out in order to gain an understanding of the chemical reactivity of the drug and the factors which contribute to its biological activity. The C-2' and/or the C-7 hydroxyl groups of taxol were substituted with acetyl, ßalanyl, silyl, succinyl, trichloroethyloxycarbonyl or carbonate linked dibenzylidene protected glucosyl groups. The C-7 position was selectively epimerized under free radical conditions and a 2'-epiacetyltaxol was produced via base catalysed epimerization. The C-2' amide became nucleophilic in the presence of base and could attack a C-2; acyl substituent. The C-13 ester side chain was selectively reduced by borohydride. The 7 position of taxol was selectively oxidized by Jones reagent and longer reaction times also oxidized the 2' position. The D rings of the 7 oxotaxols were readily opened via beta elimination; hydrogenation of the double bond in the enone of the D seco products produced a product in which the C ring was opened. The D ring was also susceptible to electrophilic attack. Reaction of taxol with triethyloxonium tetrafluoroborate or acetyl chloride/HC1 produced D seco taxols. C-7 deoxygenation was not achieved due to steric hindrance at C-7 and the instability of taxol under free radical conditions. Biological testing of modified taxols showed that substitution of the C-2' hydroxyl removed biological activity but that C-2' acyl groups were readily removed vivo. The water soluble 2'-βalanyItaxol possessed in vivo activity equal to that of taxol. Substitution of the C-7 hydroxyl did not inhibit the ability of a taxol derivative to polymerize tubulin but did decrease in vivo activity; epimerization of C-7 decreased in vivo activity slightly. A 2'-oxotaxol was found to be less active than, but still comparable to, its nonoxidized analogue. All taxol derivatives having a 7-oxo group and/or not possessing a D ring lost almost all biological activity. / Ph. D.

Yes / Boron neutron capture therapy (BNCT) has a long history of unfulfilled promises for the treatment of aggressive cancers. In the last two decades, chemists, physicists, and clinical scientists have been coordinating their efforts to overcome practical and scientific challenges needed to unlock its full therapeutic potential. From a chemistry point of view, the two current small-molecule drugs used in the clinic were developed in the 1950s, however, they both lack some of the essential requirements for making BNCT a successful therapeutic modality. Novel strategies are currently used to design new drugs, more selective towards cancer cells and tumours, as well as able to deliver high boron contents to the target. In this context, macromolecules, including polymers, are promising tools to make BNCT an effective, accepted, and front-line therapy against cancer. In this review, we will provide a brief overview of BNCT, and its potential and challenges, and we will discuss the most promising strategies that have been developed so far.

Cheung, Wing Ki. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 100-112). / Abstracts in English and Chinese. / Acknowledgments / Abbreviations / Abstract 一 English --- p.i / - Chinese --- p.iii / Chapter Chapter 1 --- General Introduction / Chapter 1.1. --- Colon Cancer / Chapter 1.1.1. --- Colon cancer statistic in Hong Kong --- p.1 / Chapter 1.1.2. --- Development of Colon cancer --- p.1 / Chapter 1.1.3. --- Treatment --- p.2 / Chapter 1.2. --- Chemistry of ascorbates / Chapter 1.2.1. --- Sodium-L-ascorbate --- p.3 / Chapter 1.2.2. --- "Sodium 5,6-benazylidene-L-ascorbate" --- p.4 / Chapter 1.3. --- "Reactive oxygen species and reactive nitrogen species, and their biological consequences" --- p.5 / Chapter 1.4. --- Cell cycle --- p.7 / Chapter 1.5. --- Autophagy --- p.8 / Chapter 1.6. --- Human colon cancer HT29 cells for anti-tumor study --- p.9 / Chapter 1.7 --- Aim of study --- p.10 / Chapter Chapter 2 --- Comparative studies of cytotoxicity of SAA and SBA in short term treatment / Chapter 2.1. --- Introduction --- p.11 / Chapter 2.2. --- Materials and Methods --- p.14 / Chapter 2.3. --- Results --- p.17 / Chapter 2.4. --- Discussion --- p.26 / Chapter Chapter 3 --- Comparative studies of SAA and SBA in oxidative stress induction and their corresponding ROS inhibitors / Chapter 3.1. --- Introduction --- p.28 / Chapter 3.2. --- Materials and Methods --- p.31 / Chapter 3.3. --- Results --- p.35 / Chapter 3.4. --- Discussion --- p.42 / Chapter Chapter 4 --- "Effects of SAA and SBA treatments on cell cycle regulatory proteins and the induction of transient cell cycle arrests in Gl, S and G2 phases Cell Cycle" / Chapter 4.1. --- Introduction --- p.45 / Chapter 4.2. --- Materials and Methods --- p.49 / Chapter 4.3. --- Results --- p.53 / Chapter 4.4. --- Discussion --- p.69 / Chapter Chapter 5 --- Autophagy induction during SBA treatment and autophagy inhibition during SAA treatment / Chapter 5.1. --- Introduction --- p.72 / Chapter 5.2. --- Materials and Methods --- p.74 / Chapter 5.3. --- Results --- p.77 / Chapter 5.4. --- Discussion --- p.91 / Chapter Chapter 6 --- General Discussion --- p.93 / References --- p.100

[Truncated abstract] Clinical and pathological predictors of survival for stage II and III colon cancer patients treated with or without chemotherapy: a population-based study. Aim: Using a population-based cohort of colorectal cancer (CRC), the major aims of this study were to: 1. Identify clinico-pathological markers that can be used to define a subset of stage II colon cancer patients with excellent prognosis and who therefore do not require referral for adjuvant chemotherapy; 2. Investigate whether there is a survival benefit from the use of adjuvant chemotherapy in a population-based cohort of stage II colon cancer; 3. Investigate stage III colon cancer patients for evidence of predictive markers for response to 5FU chemotherapy; 4. Investigate CRC for age-related differences in clinico-pathological and molecular features. Hypotheses to be tested: 1. A subset of good prognosis stage II colon cancers can be defined using routine pathological markers; 2. Females colon cancer patients gain more survival advantage from 5FU chemotherapy than males; 3. Tumours from young CRC patients have different molecular characteristics to those from older patients; 4. The underlying molecular characteristics of tumour can impact upon the response to 5FU chemotherapy. Methods: The study cohort consisted of 5,971 cases diagnosed between 1993 and 2003 representing over 90% of the CRCs diagnosed in the state of Western Australia. Results: The major findings of this translational research into colon cancer can be summarized as follows: The morphological features of serosal and vascular invasion allow for prognostic stratification of stage II colon cancer into

Thesis (MScMedSc (Obstetrics and Gynaecology))--Stellenbosch University, 2008. / BACKGROUND: The cryopreservation and transplantation of ovarian tissue have been shown to restore ovarian function temporarily and may also preserve the fertility of young female cancer patients until after their sterilizing cancer treatment. Since tissue samples are large and morphologically complex, the cryopreservation methodology is difficult to optimize and standardise. Ovarian tissue cryopreservation is therefore, still in its experimental stages and is not a routine option offered to cancer patients. OBJECTIVES: Our main aim was to initiate, develop and implement a practical ovarian tissue cryopreservation and re-transplantation protocol which would restore ovarian function, and possibly fertility, in young female cancer patients undergoing sterilizing cancer therapies in South Africa. The objective of this study was to improve the slow cryopreservation protocol for human ovarian tissue. The ultrastructural effects after cryopreservation with two well-known cryoprotectants, dimethyl sulfoxide (DMSO) and 1,2-propylene glycol (PROH), on early human follicles were investigated and compared to identify and the better cryoprotectant. MATERIALS AND METHODS: A single group experimental study design was used. The participants consisted cancer patients of the Gynaecological Oncology Unit of Tygerberg Hospital who entered on a basis of voluntary informed consent. Ovarian tissue was obtained by laparoscopic oophorectomy. After dissection of the ovary(ies), some fresh cortical tissue was sent for metastatic analysis and a few strips taken as fresh control. Remaining dissected ovarian cortical tissue sections of each patient were equally divided into the two cryoprotectant groups. Five resulting groups could be compared: i) fresh tissue (control group); tissue equilibrated in ii) DMSO; or iii) PROH and tissue equilibrated and cryopreserved in iv) DMSO or v) PROH. Five tissue samples per patient were therefore fixed for standard histological haematoxylin and eosin (HE) staining and transmission electron microscopy (TEM). Tissue samples showing early follicles on HE slides were sent for TEM processing. Ultrastructural studies on micrographs of primordial and primary follicles were assessed according to a scoring system which gave an indication of follicular health. Appropriate statistical tests were applied to analyse the mean scores where P≤0.05 was considered as statistically significant. RESULTS: No significant overall cryopreservation treatment effect was evident in any of the follicular ultrastructures evaluated. This result indicated that the cryopreservation protocol used did not induce significant damage to the cortex tissue compared to the fresh control group. Comparison of the effect of PROH and DMSO on the follicular ultrastructures showed that PROH tend to induce more extensive damage, especially after cryopreservation. Correlation studies showed significant positive relationships between the majority of the evaluated ultrastructures, especially between the oocyte and granulosa cell layer and basal membrane. The stromal cells and extracellular matrix did not correlate well with other structures. Correlations indicated that the granulosa cells, oocyte and basal lamina are affected similarly and that the damage in one of these structures may be representative of the damage in the other structures. CONCLUSION: The main aim of the study was achieved since results showed that no significant damage was induced by the cryopreservation protocols. Ovarian tissue cryopreserved in this study has shown to restore endocrine function temporarily after heterotopic autotransplantation in menopausal patients. From the electron microscopy evaluations, DMSO showed better cryopreservation results. The DMSO cryopreservation protocol was also more time efficient and has shown the most successful outcomes in the literature. The stromal tissue seemed to be affected differently by cryopreservation compared to the primordial follicle ultrastructures. Younger patients are needed for future studies since a larger initial follicular reserve may allow for larger follicle sample sizes.

Chapter One provides a general introduction into the biology and chemistry of nitric oxide, with particular focus on the role of nitric oxide in cardiovascular disease, cancer and hypoxia. It also details the types of organic functional groups used as nitric oxide donors, with detailed discussion of nitrate esters, furoxans and sydnonimines. Chapter Two discusses prostate cancer. It provides an overview into the development of prostate cancer, prostate cancer staging, and treatment. The key molecular aspects of prostate cancer are detailed, and the types of treatment available outlined. Chapter Three details the synthesis and activity of NCX-1102, a nitric oxide-donating analogue of the non-steroidal anti-inflammatory drug sulindac, and the synthetic work in the preparation of analogues of NCX-1102, using nitrate esters, furoxans and sydnonimines as nitric oxide-donating functional groups. The compounds prepared were tested against a prostate cancer cell line (PC3) and the cytotoxicity results are presented. Chapter Four describes the synthesis of nitric-oxide donating analogues of abiraterone, a CYP17 inhibitor for the treatment of prostate cancer. The results of cytotoxicity assays against PC3 cells are detailed. Chapter Five discusses the application of nitric oxide-donating functional groups in tandem with biologically active motifs. The synthesis of nitric oxide-donating amino acids, and their application to the preparation of nitric oxide-donating RGD peptides and prostate-specific membrane antigen inhibitors is presented, along with representative biological evaluation. Chapter Six introduces possible future work for the continuation of the project, suggesting the synthesis of fluorinated sydnonimines, prostate-specific membrane antigen inhibitors combined with for prostate cancer imaging and a “tool-box” of nitric oxide-donating bioconjugation reagents.

丹参是一种著名的传统中药，富含丹酚酸和丹参酮。其中，丹参酮的潜在抗肿瘤作用近年来引起众多关注。本研究评价了主要的丹参酮及其衍生物对结肠癌细胞的细胞毒性。结果显示DHTS具有最强的抗结肠癌活性和显著的肿瘤特异性细胞毒性，其细胞毒性主要由于凋亡诱导而不是引起坏死。初步的构效关系分析提示丹参酮母环结构中的A环和B环增加的离域性有助于提高其对结肠癌细胞的细胞毒性，而非二维结构及较小的D环也是进行结构改造的可能方向。 / 基于以上发现，本研究进一步探讨了DHTS的体内外抗肿瘤活性及内在机制。本研究发现DHTS的促凋亡活性并不依赖于p53的表达，而依赖于caspase活性及线粒体介导的细胞质中氧自由基 ROS及钙离子的聚集。DHTS可引起浓度及时间依赖caspase-9/-3/-7的活化而并未显著引起caspase-8的活化，这一现象发生于同样以浓度及时间依赖方式进行的线粒体中cytochrome c及AIF转位之后。在DHTS诱导的结肠癌细胞凋亡中，cytochrome c及caspase介导的凋亡通路及AIF介导的凋亡通路均被激活并显示出两条通路之间的交叉调控。 / 此外，线粒体在DHTS的促凋亡活性中的作用在本研究中被深入探讨。本研究发现线粒体可能是DHTS的一个直接靶点, 而氧化磷酸化复合体III则更可能是其作用位点。DHTS可以引起迅速而明显的线粒体功能障碍，随之引起细胞质中大量的氧自由基及钙离子聚集，诱导凋亡的产生。 / 与体外结果一致，本研究证实了DHTS对免疫缺陷小鼠中的结肠癌移植廇也具有明显的抗肿瘤作用。与溶媒对照组比较，DHTS治疗组中移植廇的增长显著被减缓，在治疗终点时的廇体积与重量也显著被降低。TUNEL检测确认DHTS诱导移植廇中癌细胞的显著凋亡。免疫荧光检测也发现DHTS诱导caspase-3及caspase-7在移植廇中癌细胞的明显活化。 / 综上所述，本研究提供了丹参酮抗结肠癌活性的一些初步构效关系的信息，为提高丹参酮抗结肠癌活性的结构改造提供一定的参考。更重要的是，本研究证明了DHTS的体内外抗结肠癌活性并探讨了其作用机制及可能靶点，为DHTS作为新的应用于抗结肠癌药物或辅助治疗用药提供了临床前研究证据。 / Salvia miltiorrhiza Bunge, also known as Danshen, rich in phenolic acid and tanshinones, has been widely used to treat various kinds of diseases including heart diseases and hepatitis in China with minimal side effects. Among the tanshinones, tanshinone I, tanshinone IIA, cryptotanshinone and dihydrotanshinone I are the major bioactive constituents in this herb. In this study, the anti-colon cancer potential of five tanshinones and six derivatives of tanshinone IIA were evaluated in several colon cancer cell lines. It was found that apoptosis but not necrosis contributed significantly to the cytotoxicity of the tanshinones. Dihydrotanshinone I (DHTS) was confirmed to be the most potent and selective anti-cancer compound among the tanshinones tested in this study. Preliminary SAR (structure activity relationship) of tanshinones reveals that the increase of delocalizability of A and B rings in the chemical structure of the tanshinones enhances their cytotoxicity on cancer cells, while compounds with a non-planar and small sized D ring region are better choices for anti-cancer effect. / The underlying mechanisms of the anti-colon cancer activity of DHTS were further studied. It was found that apoptosis induced by DHTS was p53 independent but caspase dependent, which was closely related to intracellular accumulation of ROS (reactive oxidant stress) and calcium mediated by mitochondria. A concentration- and time-dependent activation of caspase-9,-3,-7 but not caspase-8 by DHTS in HCT116 cells was detected after the translocation of cytochrome c and AIF (apoptosis inducing factor) from mitochondria. In this process, the crosstalk between the caspase-dependent and caspase-independent pathways was firstly shown in the apoptotic mechanism of DHTS. To this end, the release of cytochrome c happened first and the translocation of apoptosis inducing factor (AIF) was prevented by a pan caspase inhibitor. In the meantime, the release of cytochrome c and activation of caspase-9 and PARP (poly-ADP-ribose polymerase) cleavage were decreased after AIF knockdown. Especially, mitochondrion was suggested to be the direct target of DHTS and OXPHOS complex III but not OXPHOS complex I was probably the acting site of DHTS. / In accordance with the results obtained in vitro, the potential anti-colon cancer activity of DHTS was also observed in nude mice with xenograft tumors and the compound did not produce any observable systemic toxicity. DHTS efficiently delayed tumor growth by decreasing the tumor size and weight through the induction of apoptosis in cancer cells but not by inhibition of cell proliferation. In the same tissues, a distinct activation of caspase-3 and caspase-7 in tumor cells was also detected by immunofluorescence assay. / Collectively, the present study provides preliminary information about the SAR of the anti-colon cancer activity for tanshinones. It also confirms that DHTS is a promising compound for anti-cancer action both in vitro and in vivo. In addition, this study gives us a better understanding regarding the mechanisms of how DHTS induces apoptosis in cancer cells. All these findings could provide solid pre-clinical evidence to propel the development and application of DHTS and perhaps its derivatives as novel therapeutic or adjuvant agents for the treatment of colon 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. / Wang, Lin. / Thesis (Ph.D.) Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 122-132). / Abstracts also in Chinese. / Wang, Lin.

Leung, Jackie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 117-131). / Abstract also in Chinese. / Abstract --- p.i / 論文摘要 --- p.iii / Acknowledgement --- p.iv / List of publications --- p.vi / List of Tables --- p.vi / List of Figures --- p.vi / Table of Contents --- p.ix / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1. --- Liver cancer --- p.1 / Chapter 1.1.1. --- Hepatocellular Carcinoma (HCC) --- p.2 / Chapter 1.2. --- Lung Cancer --- p.5 / Chapter 1.3. --- Pteris semipinnata L --- p.8 / Chapter 1.4. --- Extract of PsL: 5F --- p.10 / Chapter 1.5. --- Animal models in chemotherapy researches --- p.13 / Chapter 1.5.1. --- Model of HCC --- p.13 / Chapter 1.5.2. --- Model of lung cancer --- p.15 / Chapter 1.6. --- Apoptosis: Significance of programmed cell death --- p.17 / Chapter 1.6.1. --- The extrinsic pathway --- p.18 / Chapter 1.6.2. --- The intrinsic pathway --- p.19 / Chapter 1.7. --- Apoptotic molecules related to this study --- p.22 / Chapter 1.7.1. --- Bcl-2 family --- p.22 / Chapter 1.7.1.1. --- Bax --- p.22 / Chapter 1.7.1.2. --- Bcl-2 --- p.23 / Chapter 1.7.2. --- Nuclear factor kappa B --- p.25 / Chapter 1.7.3. --- Inducible nitric oxide synthase --- p.27 / Chapter 1.8. --- Side-effects of chemotherapy --- p.29 / Chapter 1.8.1. --- Chemotherapy and liver dysfunction --- p.30 / Chapter 1.8.2. --- Nephrotoxicity of chemotherapeutic agents --- p.31 / Chapter 1.9. --- Aim of study --- p.33 / Chapter Chapter 2: --- Materials and Methodology --- p.34 / Chapter 2.1. --- Animals --- p.34 / Chapter 2.1.1. --- HCC model --- p.34 / Chapter 2.1.2. --- Lung cancer model --- p.35 / Chapter 2.2. --- Tumors induction --- p.36 / Chapter 2.2.1. --- HCC induction in C3H/HeJ mice --- p.36 / Chapter 2.2.2. --- Lung cancer induction in A/J mice --- p.37 / Chapter 2.3. --- 5F preparation --- p.38 / Chapter 2.4. --- 5F treatment --- p.39 / Chapter 2.5. --- Harvest of samples and tissues --- p.41 / Chapter 2.6. --- Tumor assessment --- p.43 / Chapter 2.7. --- Investigation of apoptosis and cell proliferation --- p.44 / Chapter 2.8. --- Immunohistochemistry --- p.47 / Chapter 2.9. --- Biochemical test --- p.51 / Chapter 2.9.1. --- Liver Function Tests (LFT) --- p.52 / Chapter 2.9.1.1. --- Aspartate aminotransferase (AST) & Alanine aminotransferase (ALT) --- p.52 / Chapter 2.9.2. --- Renal Function Test (RFT) --- p.53 / Chapter 2.9.2.1. --- Serum creatinine level (CRE) --- p.53 / Chapter 2.9.2.2. --- Blood Urea Nitrogen index (BUN) --- p.54 / Chapter 2.10. --- Statistical analysis --- p.55 / Chapter Chapter 3: --- Results --- p.56 / Chapter 3.1. --- Anti-tumor effect of 5F is dose- dependent --- p.56 / Chapter 3.2. --- 5F reduces cell proliferation and induces apoptosis in-vivo --- p.60 / Chapter 3.3. --- Effects of 5F on apoptotic signaling molecules --- p.68 / Chapter 3.3.1. --- 5F up-regulates pro-apoptotic Bax and Bak --- p.68 / Chapter 3.3.2. --- 5F down-regulates anti-apoptotic NF-kappa B and Bcl-2 --- p.76 / Chapter 3.3.3. --- 5F up-regulated iNOS in HCC but not in lung cancer --- p.88 / Chapter 3.3.4. --- Regulation on Erk1/2 was associated with treatment of 5F --- p.93 / Chapter 3.4. --- Side-effect studies of 5F --- p.97 / Chapter Chapter 4: --- Discussion --- p.105 / Chapter Chapter 5: --- Conclusion --- p.116 / Bibliography --- p.117