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In vivo and in vitro studies of the anti-cancer effect of gossypol and methotrexate.January 1985 (has links)
by Wing-yu Tang. / Bibliography: leaves 129-138 / Thesis (M.Ph.)--Chinese University of Hong Kong, 1985
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Anticancer activity studies on Annonaceous acetogenins.January 2014 (has links)
多年來,儘可能多的從植物中提取單體化合物一直是開發新型化學防癌劑和化學治療劑藥物的重要來源。 / 在本课题中,我们活性測試了从刺果紫玉盘(番荔枝科植物)中分离得到的14个番荔枝内酯化合物和7个多氧环己烯化合物,从三叉刺(豆科植物)和黄瑞香(瑞香科植物)中分离得到的4个黄酮化合物,从黄瑞香(瑞香科植物)和了哥王(瑞香科植物)中分离得到的2个香豆素化合物,以及从总状蕨藻(蕨藻科植物)中分离得到的1 个生物碱化合物,對11種人類常見癌症細胞株,如惡性黑色素瘤、肺癌、子宮頸上皮腺癌、肝癌、前列腺癌、結直腸癌的體外抗癌活性,用以建立一個全面的抗癌活性數據庫,為人們更好得了解番荔枝科植物奠定基礎。 / 在這些被篩選的單體化合物中,番荔枝內酯(ACGs)顯示出卓越的抗癌活性。它們對某些癌細胞株的細胞毒性甚至達到了nmol/l級別。例如番荔枝內酯desacetyluvaricin(Dau),對11條人類癌細胞株具有廣泛的抗增生活性,其半抑制濃度(IC₅₀)範圍從2.3 nM到37.4 μM。其中,Dau對結直腸癌細胞SW480的毒性最甚。Dau不僅具有高的抗癌效力,并對人正常纖維細胞Hs68幾乎沒有細胞毒性,半抑制濃度超過了247.5 μM。進一步的機理研究表明,Dau可導致SW480細胞產生大量過氧化物,進而導致細胞核內DNA斷裂。DNA損傷會讓MEK/ERK信號通路失活,並且影響了細胞週期調控蛋白的正常表達。例如影響細胞S週期的調控蛋白Cyclin A和Cyclin E的表達,以及影響G₁/S檢查點調控蛋白E2F的表達。由此,Dau促進SW480癌細胞穿過G₁/S檢查點,由G₁進入S期並在S期累計。最終被抑制在S週期的SW480細胞發生了壞死。以上機理的研究可為更好的理解ACG的作用機制提供一定的理論基礎。 / 番荔枝內酯是一系列長鏈脂肪酸的衍生物。它的結構的多樣性引發了我們極大的興趣去研究它的構效關係。我們比較了14個番荔枝內酯在細胞毒性和細胞週期控制方面對兩種不同的前列腺癌細胞LNCaP(p53基因野生型)和PC-3(p53基因缺失型)的影響。實驗結果表明,LNCaP細胞比PC-3更加敏感。番荔枝內酯的這種選擇性大概跟癌細胞中p53抑癌蛋白的表達水平有關。此外,關於構效關係的研究我們還發現:(1)在番荔枝內酯結構的核心系統中,四氫呋喃環的個數越多,化合物的抗癌活性越高;(2)在含有相鄰雙四氫呋喃環結構的化合物中,擁有threo/trans/threo/trans/erythro立體構型的化合物的細胞毒性比擁有threo/trans/threo/trans/threo立體構型的化合物高;(3)含單或雙四氫呋喃環結構的番荔枝內酯都將通過將LNCaP細胞抑制在G₁/G₀週期從而達到抗癌效果,並不會引起細胞凋亡;(4)含單四氫呋喃環結構的番荔枝內酯都將通過引發細胞凋亡從而達到抑制PC-3癌細胞的增長。然而含雙四氫呋喃環結構的番荔枝內酯會引發更多的PC-3細胞凋亡,並且有不同程度的細胞週期抑制;(5)在四氫呋喃環核心體系上,乙酰氧基會比羥基增加番荔枝內酯的細胞毒性;(6)雙鍵的取代基也會增加毒性效果。我們的研究結果印證了一些文獻已報導的關於番荔枝內酯構效關係的結論,同時我們也提出了一些新的假設。 / 本研究不僅增加了我們對番荔枝內酯強大的抗癌活性更全面的了解,並且通過機理研究還為它的選擇性毒性及構效關係特點提供了有重要的信息。番荔枝內酯是一類具有充滿前景抗癌化合物。在接下來的研究中,我們將致力於體內抗癌活性的研究,并擴大研究範圍,通過對多個ACG化合物的機理研究來證明我們對它的選擇性毒性的機理假設。 / For years and years, the discovery of phytochemicals as many as possible has always been an important strategy for the development of novel chemopreventive and chemotherapeutic drugs. / In this studies, we have screened 14 Annonaceous acetogenins and 7 polyoxygenated cyclohexenes isolated from the root of Uvaria calamistrata (Annonaceae), 4 flavonoids isolated from the stems of Trifidacanthus unifoliolatus (Fabaceae) and Daphne giraldii (Thymelaeaceae), 2 cumarins isolated from the stem bark of Daphne giraldii (Thymelaeaceae) and the root of Wikstroemia indica (Thymelaeaceae), and 1 alkaloid isolated from Caulerpa racemosa (Caulerpaceae). The in vitro anticancer effects of these 28 natural compounds on 11 human cancer cell lines, including malignant melanoma, lung carcinoma, cervix epithelial adenocarcinoma, liver carcinoma, prostate adenocarcinoma and colorectal adenocarcinoma, were tested to set up an overall anticancer activity database for better understanding of the biological actions of Annonaceous plants. / Among the screened natural compounds, Annonaceous acetogenins (ACGs) exhibited outstanding anticancer efficacy. The cytotoxicities of ACGs to some cancer cell lines were even at nmol/l level. For instance, desacetyluvaricin (Dau), an ACG, was identified as a novel antiproliferative agent with a broad spectrum of inhibitions against the tested 11 human cancer cell lines with the IC₅₀ values ranging from 2.3 nM to 37.4 μM, and was especially cytotoxic to SW480 human colorectal carcinoma cells. Despite this potency, Dau was virtually nontoxic toward Hs68 human fibroblasts with an IC₅₀ value exceeding 247.5 μM. Further cell death mechanism studies showed that Dau could induce large amounts of superoxide production, which subsequently induced nuclear DNA fragmentation. DNA damage may inactivate the MEK/ERK signaling pathway and disturbed the expressions of cell cycle regulators such as Cyclin A and Cyclin E, which are S phase regulators, and E2F which is the G1/S checkpoint regulator. Thereafter, Dau arrested SW480 cells in S phase by promoting SW480 cells passing through the G₁/S boundary, and then accumulating in S phase. Finally, the SW480 cells underwent necrotic cell death. This mechanism study may provide a better understanding on the action mode of ACGs. / ACGs are derivatives of long chain fatty acids. Its structural diversity kindled our great interests in its structure-activity relationship (SAR). Therefore, we compared the cytotoxicities and cell cycle regulations of the 14 ACG compounds on two different human prostate cancer cell lines, LNCaP (p53 wild-type) and PC-3 (p53 null-type). Results showed that LNCaP cells were more sensitive to ACGs than PC-3 cells. This selectivity may be due to the presence of p53 tumor suppressor gene. Moreover, we found about SAR study that (1) the more THF rings existing in the core structure of ACGs, the more potent anticancer effects of ACGs would be; (2) for the adjacent bis-THF ACGs, stereo-structure with threo/trans/threo/trans/erythro configuration is generally more cytotoxic than the one with threo/trans/threo/trans/threo configuration; (3) both mono-THF ACGs and bis-THF ACGs inhibited LNCaP cells growth by G₁/G₀ phase arrest without any apoptosis induction; (4) mono-THF ACGs inhibited PC-3 cells growth by inducing apoptosis without cell cycle disturbance. However, the bis-THF ACGs could induce more apoptosis in PC-3 cells with partially cell cycle arrest. (5) the -OAc substituent group instead of -OH in the THF system would enhance the cytotoxicity efficacies of ACGs; (6) the double bond substituent would also enhance the anticancer effect. Our studies have proved several reported disciplines about the SAR of ACGs, and also proposed some new hypothesis. / Taken together, this study not only increased our understanding on the potent anticancer effects of ACG, but also provided valuable information on explaining its special cytotoxicities and the SAR properties through underling mechanism study. ACGs are a group of promising anticancer compounds with potent and steady activities. In the future work, we should further examine the in vivo anticancer effects and study more ACGs on their action modes to validate our hypothesis on their sensitivities to certain cancer cell lines. / 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. / Xue, Junyi. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 215-236). / Abstracts also in Chinese.
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Clinical use of bone specific alkaline phosphatase of plasma and tumor tissue extract in bone forming tumor.January 1994 (has links)
by Paul, Liu Po Lung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 86-94). / ACKNOWLEDGMENT --- p.i / TABLE OF CONTENT --- p.ii / "LIST OF TABLE, FIGURE & PHOTO" --- p.viii / ABSTRACT --- p.x / Chapter CHAPTER ONE : --- INTRODUCTION --- p.1 / Chapter 1.1 --- ALKALINE PHOSPHATASE / Chapter 1.1.1 --- Alkaline Phosphatase Isoenzyme --- p.2 / Chapter 1.1.2 --- The Properties of Alkaline Phosphatases --- p.4 / Chapter 1.1.3 --- Serum Alkaline Phosphatases --- p.6 / Chapter 1.1.3.1 --- Placental Alkaline Phosphatase --- p.7 / Chapter 1.1.3.2 --- Intestinal Alkaline Phosphatase --- p.7 / Chapter 1.1.3.4 --- Skeletal Alkalne Phosphatase --- p.8 / Chapter 1.1.3.5 --- Hepatic Alkaline Phosphatase --- p.8 / Chapter 1.1.3.3 --- Renal Alkaline Phosphatase --- p.9 / Chapter 1.1.3.6 --- Miscellaneous Alkaline Phosphatase --- p.9 / Chapter 1.1.4 --- Problems in Discriminating the Skeletal and Hepatic Alkaline Phosphatase in Serum --- p.11 / Chapter 1.1.5 --- Quantitative measure of the Bone-Specific Alkaline Phosphatase --- p.12 / Chapter 1.1.6 --- Qualitative Detection of ALP isoenzymes --- p.14 / Chapter 1.2 --- OSTEOSARCOMA --- p.17 / Chapter 1.2.1 --- Definition --- p.17 / Chapter 1.2.2 --- Epidemiology and Statistics --- p.17 / Chapter 1.2.3 --- Clinical Presentation --- p.18 / Chapter 1.2.4 --- Radiographic finding --- p.19 / Chapter 1.2.5 --- Staging of Musculoskeletal Neoplasms --- p.20 / Chapter 1.2.6 --- Treatment of osteosarcoma --- p.21 / Chapter 1.2.6.1. --- Chemotherapy in Prince of Wales Hospital --- p.21 / Chapter 1.3 --- PLASMA AND TISSUE ALKALINE PHOSPHATASE IN NORMAL AND NEOPLASTIC CONDITION --- p.23 / Chapter 1.3.1 --- Normal values of plasma alkaline phosphatase --- p.23 / Chapter 1.3.2 --- Clinical use of elevated plasma & tissue alkaline phosphatase level in neoplastic conditions --- p.25 / Chapter 1.3.2.1 --- Helping the Diagnosis of the Osteosarcoma --- p.25 / Chapter 1.3.2.2 --- Monitoring the effect of chemotherapy --- p.26 / Chapter 1.3.2.3 --- Predicting the clinical course --- p.26 / Chapter 1.3.3 --- Qualitative measurement of ALP in plasma and tissue extract of osteosarcoma patient --- p.29 / Chapter 1.4 --- AIM AND SCOPE OF THE PRESENT DISSERATION --- p.30 / Chapter CHAPTER TWO : --- MATERIALS AND METHODS --- p.32 / Chapter 2.1 --- DIFERENT GROUPS OF PATIENTS --- p.33 / Chapter 2.1.1 --- Monitering the plasma bone specific ALP --- p.33 / Chapter 2.1.1.1 --- Osteosarcoma group --- p.33 / Chapter 2.1.1.2 --- Benign bone tumour group --- p.34 / Chapter 2.1.1.3 --- Metastasis group --- p.34 / Chapter 2.1.2 --- Collection of plasma samples preserve of tumor tissue --- p.34 / Chapter 2.2 --- QUANTITATIVE ANALYSIS OF THE PLASMA AND TISSUE BONE SPECIFIC ALKALINE PHOSPHATASE --- p.36 / Chapter 2.2.1 --- Extraction of tissue ALP --- p.36 / Chapter 2.2.1.1. --- Reagent --- p.36 / Chapter 2.2.1.2. --- Homogenization of the bone tissue --- p.36 / Chapter 2.2.1.3. --- Extraction of ALP --- p.37 / Chapter 2.2.2 --- Assay for Bone-specific ALP --- p.38 / Chapter 2.2.2.1. --- Reagents --- p.38 / Chapter 2.2.2.2. --- Procedures --- p.38 / Chapter 2.3 --- QUALITATIVE MEASUREMENT OF ALP ISOENZYME --- p.40 / Chapter 2.3.1 --- Equipment required --- p.40 / Chapter 2.2.2 --- Practical procedure --- p.40 / Chapter 2.3.3.1 --- Gel casting --- p.40 / Chapter 2.3.3.2 --- Sample preparation and application --- p.42 / Chapter 2.3.3.3 --- Electrofocusing --- p.42 / Chapter 2.3.3.4 --- Western blotting of the protein --- p.43 / Chapter 2.3.3.5 --- Detection methods --- p.45 / Chapter 2.4 --- METHOD OF STATISTICAL ANALYSIS --- p.48 / Chapter CHAPTER THREE : --- RESULTS --- p.49 / Chapter 3.1 --- QUANTITATIVE MEASUREMENT OF PLASMA AND TISSUE BONE SPECIFIC ALKALINE PHOSPHATASE --- p.50 / Chapter 3.1.1 --- General Information of the patients monitoring --- p.50 / Chapter 3.1.2 --- Pretreatment evaluation --- p.52 / Chapter 3.1.3 --- Correlation between the pretreatment plasma ALP levels and prognosis in the osteosarcoma patient group --- p.57 / Chapter 3.1.4 --- "Correlation between the pre-operational, post- operational plasma ALP levels and the prognosis of osteosarcoma" --- p.59 / Chapter 3.1.5 --- Analysis of plasma ALP levels at the time of relapse in osteosarcoma patients --- p.61 / Chapter 3.1.6 --- Usefulness of the plasma ALP levels for monitoring the effectiveness of chemotherapy --- p.62 / Chapter 3.1.7 --- Correlation between the ALP levels in the tumor extract and the prognosis of the osteosarcoma --- p.64 / Chapter 3.2 --- QUALITATIVE ANALYSIS OF THE PLASMA AND TISSUE ALKALINE PHOSPHATASE LEVEL --- p.67 / Chapter 3.2.1 --- Comparison of the result of Isoelectric focusing of the plasma ALP of the osteosarcoma patients and the normal subjects --- p.67 / Chapter 3.2.1 --- Result of Isoelectric focusing of the ALP isoenzymes in the tissue extract of the osteosarcoma and normal bone --- p.70 / Chapter CHAPTER FOUR : --- DISCUSSION --- p.72 / Chapter 4.1 --- USE OF QUANTITATIVE MONITORING OF PLASMA ALP AND MEASURING TISSUE ALP IN OSTEOSARCOMA PATIENTS --- p.73 / Chapter 4.2 --- ISOELECTRIC FORCUSING AS A TECNIQUE FOR QUALITATIVE MEASUREMENT OF PLASMA AND TISSUE ALKALINE PHOSPHATASE --- p.80 / Chapter CHAPTER FIVE : --- CONCLUSION --- p.83 / Chapter CHAPTER SIX : --- BIBILOGRAPHY --- p.85
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Intervenções para redução de diarréia em pacientes recebendo quimioterapia para câncer colorretal : revisão sistematica /Silveira, Renata Filpi Martello da. January 2013 (has links)
Orientador: Paulo Eduardo de Oliveira Carvalho / Coorientador: Antonio José Maria Cataneo / Banca: Olavo Ribeiro Rodrigues / Banca: Celso Vieira de Souza Leite / Resumo: A Revisão Sistemática avaliou a eficácia e segurança de diferentes intervenções farmacêuticas no tratamento da diarreia induzida por quimioterapia em pacientes com câncer colorretal. A Revisão incluiu ensaios clínicos randomizados e controlados com diferentes intervenções farmacológicas para o tratamento de diarreia induzida por quimioterapia em pacientes com cancer colorretal. Os participantes foram pacientes com cancer colorretal e diarreia induzida por quimioterapia, randomizados para as diferentes intervenções no tratamento da diarreia. O controle se realizou pelo uso de algumas drogas, placebo ou nenhuma intervenção. Os desfechos primários medidos foram redução ou cessação da diarreia, mudanças no protocolo de quimioterapia e morte durante a quimioterapia. Os desfechos secundários foram custo do tratamento, efeitos adversos atribuídos à intervenção e à hospitalização durante a quimioterapia. Os métodos de busca para identificação dos estudos foram CLib, Medline e Embase. Avaliaram-se os estudos presentes na busca e identificaram-se vinte e um estudos que preenchiam os critérios de inclusão. Foram avaliados esses estudos com textos completos, utilizando-se a folha de extração de dados. Apenas seis estudos restaram para a inclusão. A Revisão Sistemática demostrou a necessidade da realização de um ensaio clínico randomizado prospectivo e controlado, especificando a melhor intervenção farmacológica no controle da diarreia induzida pela quimioterapia em pacientes com câncer colorretal / Abstract: A Systematic Review was conducted to evaluate the effectiveness and safety of different pharmacological interventions to treat chemotherapy induced diarrhoea in patients with colorectal cancer. This Systematic Review included randomized controlled trials comparing different pharmacological interventions to treat chemotherapy induced diarrhoea in patients with colorectal cancer. Participants were patients with CRC and chemotherapy induced diarrhoea, randomized to different interventions for the treatment of diarrhoea. Intervention was with drug used alone or associated to other drug for the treatment CID. The control was the use of other drug, placebo or no intervention. Primary outcome measured was the reduction or the cessation of diarrhoea, Changes in the chemotherapy protocol, death during chemotherapy and the secondary outcome costs of treatment, any adverse effect attributed to the intervention, hospitalization during chemotherapy. The search methods for identification of studies were CLib, Medline and Embase. The authors evaluated the studies present in the search and identified thirteen studies met the inclusion criteria. The authors evaluated these studies with complete texts using the form extraction, but did not identify any study. A Systematic Review demonstrated that the necessity of conducting a randomized prospective controlled by specifying the best pharmacological intervention in the control of chemotherapy-induced diarrhea in patients with colorectal cancer. Keywords: Cancer diarrhea treatment, chemotherapy, colorectal cancer / Mestre
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The clonal architecture and tumour microenvironment of breast cancers are shaped by neoadjuvant chemotherapySammut, Stephen John January 2019 (has links)
Neoadjuvant chemotherapy has become standard practice in patients with high-risk early breast cancer as it improves rates of breast conservation surgery and enables prediction of recurrence and survival by using response to treatment as a surrogate. Previous studies have focused on generating molecular datasets to develop prediction models of response, though little is known on how tumours and their microenvironments are modulated by neoadjuvant chemotherapy. The thesis aims at molecularly characterising tumour changes during neoadjuvant chemotherapy in a cohort of 168 patients. Serial tumour samples at diagnosis, and, when available, midway through chemotherapy and on completion of treatment were profiled by shallow whole genome sequencing, deep exome sequencing and transcriptome sequencing, resulting in the generation of an unprecedented genomics dataset with tumours in situ while patients received chemotherapy. Molecular predictors of response to chemotherapy were inferred from the diagnostic biopsy. Several novel observations were made, including previously undescribed associations between copy number alterations, mutational genotypes, neoantigen load, HLA genotypes and intra-tumoural heterogeneity with chemosensitivity. Possible mechanisms of chemoresistance included LOH at the MHC Class I locus, decreased expression of MHC Class I and II genes and drug influx molecules, as well as increased expression of drug efflux pumps. A complex relationship between proliferation, tumour microenvironment composition (TME) and response to treatment was explored by deconvoluting bulk RNAseq data and performing digital pathology orthogonal validation. Clonal and microenvironment dynamic changes induced by/associated with chemotherapy were then modelled. Two types of genomic responses were identified, one in which the clonal composition was stable throughout treatment and another where clonal emergence and/or extinction was evident. Validation by multi-region deep sequencing confirmed the dynamics of the clonal landscape. Clonal emergence was shown to be associated with higher proliferation and decreased immune infiltrate, with an increase in genomic instability and homologous recombination deficiency during treatment. The immune TME composition and activity mirrored response to treatment, with cytolytic activity and innate and adaptive immune infiltrates linearly correlating with the degree of residual disease remaining after chemotherapy. Finally, the circulating tumour DNA (ctDNA) genomic landscape was explored by using shallow whole genome sequencing and targeted sequencing of plasma DNA. Tumour mutations detected on exome sequencing were also detected in ctDNA in plasma, supporting the use of liquid biopsies as a biomarker for monitoring response to therapy and detection of minimal residual disease.
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Interaction of nutrition and chemotherapy in the cancer patientEngle, Deborah Ann January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Immunomagnetic and pharmacologic purging of tumor-involved bone marrow for patients undergoing regimens of high-dose chemotherapy and autologous bone marrow supportPap, Stephen A. January 1992 (has links)
Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Autologous Bone Marrow Transplantation (ABMT) provides a way to rescue the hematopoietic system in patients receiving high dose chemotherapy. Solid tumors like lung and breast cancer are the targets for new therapies that involve high dose chemotherapy with AMBT due to their growth and pathologic characteristics. Reinfusion of bone marrow with metastatic neoplastic cells could also seed viable tumor cells, and thus be a reason for treatment failure, restricting high-dose chemotherapy with bone marrow support to patients whose marrow is morphologically free of tumor cells. The use magnetic beads for physical separation of tumor from normal cells and the use of a toxin delivered by a monoclonal antibody are examined as two purging methods for treatment.
The use of magnetic beads conjugated with specific antibodies (SM1, LAM2 and LS1) against tumor antigens to purge 2-3 logs of Small Cell Lung Cancer (SCLC) contamination from bone marrow is demonstrated. Optimal performance calls for short double exposure to anti-tumor cell-antigen monoclonal antibodies, followed by exposure to magnetic beads coated with antibodies specific for the monoclonal anti-SCLC antibodies, maintaining a bead-to-cell ratio of 10:1 to 100:1.
Specific toxin delivery to three breast cancer cell lines (ZR-75, BT20 and MCF7) expressing the DF3 antigen was demonstrated by the use of DF3 immunotoxin (DF3-IT). The optimal concentration of the DF3-IT immunotoxin for highest tumor kill was shown to be 1x1Q-9 M, but this caused a loss of bone marrow progenitor cell colonies of about 30%.
Both methods are limited chiefly by the level of antigen expression in the target tumor cells. The purging efficiency could be improved by targeting a wider range of antigens or by inducing higher levels of antigen expression. From the clinical perspective, the advantages and need for purging involved bone marrow to bring about substantially improved curative strategies remains a question still unanswered. / 2031-01-01
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Markers of treatment response for gastro-oesophageal cancersMirza, Ahmad January 2012 (has links)
Introduction: The incidence of gastro-oesophageal cancers has increased considerably over the last decade. As the disease is associated with a poor prognosis, there is a need to identify markers of treatment response which could be used in the future to improve the management of gastro-oesophageal tumours. Aims: 1) To compare the ability of published histological grading criteria (Becker, Mandard and Ninomiya) to assess response to neo-adjuvant chemotherapy (NCT) in gastro-oesophageal cancers. 2) To evaluate the expression of thymidylate synthase (TS) in pre-treatment diagnostic biopsy samples as a predictive marker of response to NCT. 3) To investigate whether measurements of hypoxia obtained using pimonidazole are prognostic for treatment outcome in patients with gastro oesophageal adenocarcinoma (ACC). 4) To study the prognostic significance and clinicopathological associations of epithelial mesenchymal transition (EMT) related proteins S100A4, Vimentin and Snail1 in gastro-oesophageal junction (GOJ) tumours. 5) To evaluate the ability of dynamic contrast enhanced (DCE) MRI to assess chemoradiotherapy (CRT) induced changes in oesophageal cancer. Methods: 1) Formalin fixed paraffin embedded (FFPE) tumour blocks and haematoxylin and eosin stained slides of samples from resected tumours (n=66) were obtained from patients who received NCT for gastric and GOJ tumours. The slides were scored independently by two observers and kappa scores calculated. 2) Pre-treatment diagnostic tissue biopsy samples were obtained from 45 patients with gastric and GOJ cancer who received NCT. TS expression was assessed using immunohistochemistry (IHC) and scored by two observers. The clinical and pathological data were analysed. 3) 57 patients were prospectively administered intravenous pimonidazole and the tumour specimens were collected both at staging laparoscopy and resection. IHC was performed to assess pimonidazole expression and determine its association with clinico-pathological factors. 4) Tissue microarrays were prepared from resection specimens from GOJ ACC. IHC was performed to investigate EMT related protein expression. 5) DCE-MRI was performed on five patients diagnosed with oesophageal cancer treated with CRT. Multiple pharmacokinetic parameters were evaluated. Findings: 1) Becker's histological grading criteria was the most reproducible and prognostic of outcome. The incidence of complete histological response (5%) was low in patients receiving NCT. 2) No prognostic benefit of TS expression was identified. 3) Results from only 34 patients were available for analysis. 77% pimonidazole positivity was observed. Preoperative anaemia was associated with significant tumour pimonidazole expression (p=0.04). Pimonidazole was not prognostic for outcome. 4) The overall positive expression was S100A4 (85%), Vimentin (14%) and Snail1 (89%). The increased expression of S100A4 at the tumour body (p=0.02) and luminal surface (p=0.01) was associated with a poor outcome. 5) Significant changes were measured in DCE-MRI pharmacokinetic parameters after CRT. Conclusion: 1) Becker's histological response grading criteria should be further studied in routine clinical practice for response assessment to NCT. 2) TS should be explored further as a marker of NCT response in gastro-oesophageal cancer. 3) Hypoxia is a characteristic feature of upper gastrointestinal ACC and is associated with anaemia. 4) S100A4 is the most useful marker of EMT in GOJ adenocarcinoma. 5) DCE-MRI tracer kinetic parameters should be explored in a larger study to assess their ability to monitor the efficacy of and predict response to neo-adjuvant treatment.
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Inibição terapêutica da interação MDM2-p53 : uma alternativa para o tratamento do carcinoma adenoide císticoNör, Felipe January 2016 (has links)
Introdução: O carcinoma adenoide cístico (CAC) é uma das neoplasias de glândula salivar mais comuns para o qual não se encontra quimioterapia eficaz. Um conceito emergente na terapia do câncer é atingir proteínas especificas do tumor. MDM2 (murine double minute 2) é um importante inibidor do supressor tumoral p53, e sua expressão é aumentada em CAC. O objetivo do Artigo 1 foi avaliar o efeito de um novo inibidor da interação MDM2-p53 (MI-773) no CAC in vitro e in vivo. O Artigo 2 teve como objetivo entender o papel da combinação de MI-773 com cisplatina, além de avaliar a recorrência de CAC frente a regime neoadjuvante de MI-773. Materiais e Métodos: 3 modelos de xenoenxerto derivado de paciente (XEDP, UM-PDXHACC- 5; ACCx6; ACCx9) e 5 culturas primarias de CAC (UM-HACC-1, -2A, -2B, -5, -6) foram usados para experimentos in vitro e in vivo. Ensaio de Sulforrodamina B (SRB) foi realizado para avaliar o efeito dos agentes experimentais na viabilidade celular, além de determinar valores de IC50. Western blots revelaram a expressão de p53, fosfo-p53, MDM2, p21, PUMA, BAX, Bcl-2 e Bcl-xL. Lâminas histológicas (UMPDX- HACC-5) foram avaliadas por imunohistoquímica e imunofluorescência para determinar a localização de p53. Técnica de TUNEL in situ revelou o número de células de UM-PDX-HACC-5 no processo de apoptose. Citometria de fluxo foi realizada para determinar o efeito da terapia na proporção de células-tronco tumorais (ALDHhighCD44high) e para avaliar o ciclo celular. Para os estudos in vivo, animais transplantados com tumores (UM-PDX-HACC5, ACCx6, ou ACCx9) receberam protocolo terapêutico (MI-773 – gavagem; cisplatina – injeção intraperitoneal; ou veículo controle) conforme indicado. ANOVA, seguido de testes post-hoc (Tukey), Mann-Whitney U-test ou Student’s t-test foram usados para determinar as diferenças no crescimento tumoral, peso, volume, apoptose, viabilidade celular, expressão de TUNEL e p53. Significância estatística: p<0.05. Resultados: MI-773 causa regressão do tumor em todos os modelos préclínicos de CAC. Doses diárias de 100mg/kg de MI-773 reduziram significativamente o volume tumoral quando comparado com doses intermediárias (10 ou 50 mg/kg MI-773) ou veículo controle, em todos os modelos de CAC. Alternativamente, camundongos transplantados com tumores UM-PDX-HACC-5 receberam doses semanais de MI-773 (200 mg/kg) e/ou cisplatina (5 mg/kg) por 30 dias, a fim de se avaliar o efeito da combinação das drogas. MI-773, como agente único, causou regressão tumoral, sendo mais efetivo do que a cisplatina. Cisplatina, por outro lado, mostrou limitado efeito terapêutico, estabilizando o crescimento tumoral. Notavelmente, a combinação MI-773 + cisplatina foi mais efetiva do que os agentes isoladamente, e não foi verificada retomada do tumor no período pósoperatório. Importantemente, os protocolos experimentais não comprometeram a saúde geral dos animais. Coletivamente, estes resultados in vivo demonstram que MI-773 atua como mediador na regressão tumoral de CAC e sensibiliza os tumores à cisplatina. A inibição terapêutica da interação MDM2-p53 ativa p53 e induz apoptose. MI-773 potentemente induz expressão de p53, seu alvo p21 e proteínas relacionadas à apoptose, como PUMA, BAX, Bcl-2 e Bcl-xL in vitro e in vivo. Análise do ciclo celular mostrou que a inibição terapêutica da interação MDM2-p53 por MI- 773 causa parada no ciclo celular no primeiro ponto de checagem (G1). Marcação por TUNEL revelou número significativamente maior de células em apoptose quando tumores de UM-PDX-HACC-5 foram tratados com MI-773 em comparação com controle (p<0.05) Utilizando o mesmo modelo de xenoenxerto, a técnica de imunohistoquímica mostrou que MI-773 não somente aumentou a porcentagem de células p53-positivas (p<0.001), como causou uma translocação parcial de p53 ao citoplasma. MI-773 reduz a fração de células-tronco tumorais (CTT) e previne recorrência do CAC. Tratamento com MI-773 como agente único ou combinado com cisplatina reduziu a fração de CTT (p<0.05). Notavelmente, nenhum animal tratado com regime neoadjuvante de MI-773 apresentou recorrência tumoral mesmo após 300 dias de acompanhamento. Em contraste, em 62,5% dos animais do grupo controle houve recorrência (p=0.0097). Conclusões: Em resumo, os estudos demonstram que a inibição terapêutica da interação MDM2-p53 com MI-773 é uma estratégia antitumoral eficaz, é capaz de sensibilizar tumores à cisplatina e previne recorrência neste modelo pré-clínico de CAC. Coletivamente, os dados sugerem que pacientes com carcinoma adenoide cístico podem ser beneficiados através de terapias-alvo contra MDM2. / Introduction: Adenoid cystic carcinoma (ACC) is one of the most common salivary gland malignancies for which no effective chemotherapy is available. An emerging concept in cancer therapy is to target specific tumor-related proteins. Murine double minute 2 (MDM2) is an important inhibitor of the tumor suppressor p53 and has been found overexpressed in ACC. Paper #1 aimed to evaluate the effect of a novel small molecule inhibitor of the MDM2-p53 interaction (MI-773) on ACC in vitro and in vivo. Paper #2 aimed to understand the role of combining MI-773 with cisplatin, and to evaluated ACC recurrence using a neoadjuvant regimen of MI-773. Material and Methods: 3 patient-derived xenograft (PDX) models (UM-PDX-HACC-5; ACCx6; ACCx9) and 5 low passage primary human ACC cells pools (UM-HACC-1, -2A, -2B, - 5, -6) were used for in vivo and in vitro experiments. Sulforhodamine B (SRB) assay was performed to evaluate the effect of experimental agents on ACC cell viability and to determine IC50 values. Western blots revealed the expression of p53, phosphop53, MDM2, p21, PUMA, BAX, Bcl-2 and Bcl-xL. Histological sections from UM-PDXHACC- 5 tumors were stained using immunohistochemistry and immunofluorescence techniques to determine p53 status. In situ TUNEL staining revealed the number of UM-PDX-HACC-5 cells undergoing apoptosis. Flow cytometry was carried out to determine the effect of therapy on the proportion of cancer stem cells (ALDHhighCD44high) and for cell cycle analysis. For in vivo studies, mice harboring UM-PDX-HACC5, ACCx6, or ACCx9 tumors were treated following specific therapeutic protocol (MI-773 – gavage; cisplatin – intraperitoneal injection; or vehicle control), as opportunely indicated. One-way ANOVA, followed by post-hoc tests (Tukey), Mann-Whitney U-test or Student’s t-test were used to determine significant differences in tumor growth, weight, volume, apoptosis levels, cell viability, TUNEL and p53 expression. Significance was determined at p<0.05. Results: MI-773 caused tumor regression in all ACC PDX models. Daily doses of 100 mg/kg MI- 773 significantly reduced tumor volume when compared to intermediate doses (10 or 50 mg/kg MI-773) or vehicle-treated controls in all ACC xenograft models. Alternatively, mice harboring UM-PDX-HACC-5 tumors received either weekly doses of MI-773 (200 mg/kg) and/or cisplatin (5 mg/kg) for 30 days, in order to evaluate the effect of this drug combination. MI-773 as single agent caused tumor regression, being more effective than single agent cisplatin. Cisplatin showed limited therapeutic response stabilizing tumor growth. Notably, combination of MI-773 with cisplatin was more effective than single agent therapies and no tumor rebound was observed during the follow up period. Importantly, experimental protocols did not compromise the overall health status of mice. Collectively, these in vivo results demonstrate that MI-773 mediates ACC tumor regression, and sensitizes ACC xenograft tumors to cisplatin. Therapeutic inhibition of the MDM2-p53 interaction activates p53 and induces apoptosis. MI-773 potently induced the expression of p53, its downstream target p21 and apoptosis-related proteins PUMA, BAX, Bcl-2 and Bcl-xL in vitro and in vivo. Cell cycle analysis showed that therapeutic inhibition of the MDM2-p53 interaction by MI-773 causes cell cycle arrest at the first checkpoint (G1). In situ TUNEL revealed a significant higher number of cells undergoing apoptosis in UMPDX- HACC-5 tumors treated with MI-773 compared to vehicle control (p<0.05). Using the same xenograft model, immunohistochemistry assay showed that MI-773 not only increased the percentage of p53-positive cells (p<0.001), but also caused a partial translocation of p53 to the cytoplasm. MI-773 reduces the fraction of cancer stem cells (CSC) and prevents recurrence in ACC. Treatment with MI-773 as single agent or combined with cisplatin significantly reduced the fraction of CSC (p<0.05). Notably, not a single animal treated with neoadjuvant MI-773 presented recurrence even after 300 days of follow-up. In contrast, 62,5% of mice that received vehicle control experienced tumor reappearance within this time period (p=0.0097). Conclusions: In summary, these studies demonstrate that therapeutic inhibition of the MDM2-p53 interaction with MI-773 is an effective anti-tumor strategy that mediates tumor regression, sensitizes tumors to cisplatin and prevents recurrence in this pre-clinical model of ACC. Collectively, these data suggest that patients with adenoid cystic carcinoma might benefit from MDM2-targeted therapies.
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Efeitos tóxicos da quimioterapia metronômica a base de ciclofosfamida ou metotrexato em ratos Wistar /Correal Suárez, María Lucía January 2017 (has links)
Orientador: Áureo Evangelista Santana / Coorientadora: Annelise Carla Camplesi / Banca: Marco Antônio de Andrade Belo / Banca: Thiago Demarchi Munhoz / Resumo: A quimioterapia metronômica é uma estratégia de uso crescente em Medicina Veterinária, que emprega fármacos em baixas doses e por longos períodos de tempo para controlar o crescimento tumoral. Objetivou-se avaliar os efeitos tóxicos de dois quimioterápicos antineoplásicos em animais livres de tumores seguindo esquemas metronômicos, assim como os efeitos residuais uma vez que a terapia foi suspensa. Para tanto, foram empregados 54 ratos Wistar, divididos em 3 grupos de tratamento de 18 animais cada, que receberam doses baixas de ciclofosfamida (CPX), metotrexato (MTX) ou placebo (grupo controle, CTR), via oral, por meio de gavage, durante 45 dias. Os animais tiveram acompanhamento periódico para pesagem e monitoramento clínico e do consumo de alimento e água. Realizou-se eutanásia em seis animais de cada grupo aos 30 (M1), 45 (M2) e 60 dias (M3), para coleta de amostras para hemograma, bioquímica sérica, citologia de medula óssea e análise histopatológica de baço, fígado, rim, intestino, pulmão, coração, cérebro e artéria. Empregou-se o teste de Qui-quadrado para análise estatística das variáveis não paramêtricas e o teste T-student para amostras não pareadas ou uma ANOVA seguida de uma comparação múltipla de Tukey para as variáveis paramêtricas. Seis animais do grupo CPX morreram, portanto a terapia foi suspensa aos 30 dias de tratamento, mantendo o período de observação até 45 dias. Os animais tratados com CPX exibiram significativa redução de peso e do consumo de alimento e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Metronomic chemotherapy is a growing strategy in veterinary medicine that uses low doses of antineoplastic drugs for sustained periods of time to control tumor growth. This work aimed to evaluate toxic effects of metronomic chemotherapy schemes in tumor-free animals, and residual toxicity once treatment was suspended. There were used 54 healthy Wistar rats, divided in 3 groups (18 animals each), that received low-doses of cyclophosphamide (CPX), methotrexate (MTX) or placebo (control group, CTR) by oral gavage during 45 days. Clinical alterations, body weight, water and food intake were monitored periodically. Euthanasia was practiced within 6 animals from each group at 30 (M1), 45 (M2) and 60 days (M3) to perform hematological, biochemical and histopathologic analysis (spleen, liver, kidney, gut, lung, heart, brain and artery), and bone marrow cytology. An unpaired T-student test or a one-way ANOVA in conjunction with a Tukey multiple comparison test were done to analyze parametrical data, as a Chi-square test for semi-quantitative parameters. Six animals treated with CPX died and therapy was suspended at 30 days, within 15 days of observation after withdrawal. CPX treated animals exhibited significant reduction of weight gain, water and food intake (p<0.05), and clinical alterations related to respiratory and neuromuscular involvement, which even persisted after CPX withdrawal. At M1, significant neutrophil augmentation and reduction of leukocytes, lymphocytes and albumin was predominant in blood, as bone marrow reduction of lymphocytes, plasmatic cells and mature erythroid populations were significantly prevalent (p<0.05). At M2, only higher neutrophils count and reduction of lymphocytes persisted, as depletion of mature erythroid populations (p<0.05). MTX treated animals only evidenced mild to moderate (Complete abstract click electronic access below) / Mestre
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