Triple-negative breast cancers (TNBCs) are highly refractive to current treatment strategies, and new multi-targeted treatments need to be elucidated. Combination therapy that includes targeting the murine double minute 2 (Mdm2) signaling axis offers a promising approach. Protein-protein interaction inhibitors such as Nutlin-3a block the binding of key signaling molecules such as p53, p73α, and E2F1 to the hydrophobic pocket of Mdm2 and can lead to activation of cell-death signaling pathways. Since clinical trials for TNBC are evaluating the DNA damaging agent carboplatin, the objective of this thesis was to evaluate the therapeutic potential and mechanism of action of combination carboplatin and Nutlin-3a to treat TNBC. In TNBC cell lines with a mutant p53 background, we determined if modulation of Mdm2 function in the context of carboplatin-mediated DNA damage resulted in a synergistic inhibition of cell growth. Several ratios of carboplatin:Nutlin-3a were strongly synergistic in increasing cell death, with combination indices of 0.5 and lower. Mechanistic studies indicated that drug sensitivity and Mdm2 expression were dependent on p73. Mdm2 localized to a larger degree in the chromatin fraction isolated from cells treated with the combination treatment consistent with observations by others that Mdm2 binds to the Mre11/Rad50/Nbs1 complex, inhibits the DNA damage response, and increases drug sensitivity. In vivo efficacy experiments were conducted in the TMD231 orthotopic mammary fat pad model in NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) mice. For assessment of baseline tumor burden and randomization, fluorescent imaging of E2-Crimson expressing TMD231 cells was performed. Following Nutlin-3a and carboplatin combination treatment, there was a statistically significant reduction in primary tumor volume as well as lung metastases with significantly increased probability of survival compared to Vehicle and single drug treatments (p<0.001). While there was a decrease in bone-marrow cellularity, this did not lead to bone-marrow aplasia, and body weights recovered to normal levels within 7 days post-treatment. The present studies demonstrate the promise of Mdm2 as a therapeutic target in combination with conventional therapy, increase our understanding of how to potentiate DNA damage in cancers, and may lead to new clinical therapies for triple-negative primary and metastatic breast cancer.

Cheung, Tsz Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 97-116). / Abstracts in English and Chinese. / Thesis/Assessment Committee Members --- p.ii / Declaration for Plagiarism and Copyright --- p.iii / Abstract --- p.iv / 摘要 --- p.vi / Acknowledgements --- p.viii / Table of Contents --- p.ix / List of Abbreviations --- p.xii / List of Figures --- p.xv / List of Tables --- p.xvi / Chapter CHAPTER TWO: --- Introduction / Chapter 1.1 --- Background Information / Chapter 1.1.1 --- Breast Cancer --- p.1 / Chapter 1.1.2 --- General Statistics of Breast Cancer Worldwide and in Hong Kong --- p.1 / Chapter 1.1.3 --- Risk Factors for Breast Cancer --- p.2 / Chapter 1.1.4 --- Breast Cancer Treatment and Side Effects --- p.2 / Chapter 1.1.5 --- Types of Breast Cancer --- p.3 / Chapter 1.2 --- Estrogen and Estrogen Receptor / Chapter 1.2.1 --- Estrogen --- p.4 / Chapter 1.2.2 --- Estrogen Receptor --- p.5 / Chapter 1.2.3 --- Estrogen Receptor mediated Gene Transcription --- p.5 / Chapter 1.2.4 --- Estrogen Receptor Alpha and Estrogen Receptor Beta --- p.6 / Chapter 1.2.5 --- Estrogen Receptor Positive Breast Cancer and Treatment --- p.7 / Chapter 1.3 --- Estrogen metabolism and Cytochrome P450 family 1 (CYP1) members / Chapter 1.3.1 --- Estrogen Metabolism in Human --- p.9 / Chapter 1.3.2 --- CYP1A1 and CYP1B1 --- p.9 / Chapter 1.3.3 --- Estrogen Metabolism in Breast --- p.10 / Chapter 1.3.4 --- Carcinogenesis of Estrogens and Estrogen Metabolites --- p.13 / Chapter 1.3.5 --- The Importance of CYP1B1 in Carcinogenesis --- p.15 / Chapter 1.4 --- Aryl Hydrocarbon Receptor / Chapter 1.4.1 --- General Information of Aryl Hydrocarbon Receptor --- p.16 / Chapter 1.4.2 --- Signaling/Regulation Pathways of Aryl Hydrocarbon Receptor --- p.17 / Chapter 1.4.3 --- Crosstalk with Estrogen Receptor --- p.17 / Chapter 1.5 --- Introduction of Herba Scutellaria Barbata and its active ingredient Pheophorbide a --- p.19 / Chapter 1.6 --- Hyposthesis and Objectives --- p.21 / Chapter CHAPTER TWO: --- Direct Cytotoxic/Cytostatic Effect of Pheophorbide a / Chapter 2.1 --- Backgrounds --- p.22 / Chapter 2.2 --- Materials / Chapter 2.2.1 --- Chemicals --- p.24 / Chapter 2.2.2 --- Cell Lines --- p.26 / Chapter 2.2.3 --- "Cell Culture Mediums, Buffers and Consumables" / Chapter 2.2.3.1 --- Roswell Park Memorial Institute Tissue Culture Medium1640 (RPMI1640) --- p.26 / Chapter 2.2.3.2 --- RPMI 1640 (Phenol Red-free) --- p.26 / Chapter 2.2.3.3 --- Serum supplement - Fetal Bovine Serum (FBS) --- p.27 / Chapter 2.2.3.4 --- Serum supplement - Charcoal/Dextran Stripped FBS --- p.27 / Chapter 2.2.3.5 --- Antibiotics - Penicillin-Streptomycin (P/S) --- p.27 / Chapter 2.2.3.6 --- Trypsin (0.25%) with EDTA --- p.27 / Chapter 2.2.3.7 --- Trypsin (2.5%) (Phenol Red-free) with EDTA --- p.28 / Chapter 2.2.3.8 --- Dulbeccóةs Phosphate-Buffered Saline (D-PBS) --- p.28 / Chapter 2.2.3.9 --- Tissue Culture Flasks and Multi-well Plate --- p.28 / Chapter 2.2.3.10 --- Trypan Blue Solution --- p.29 / Chapter 2.2.4 --- Reagents for Direct Cytotoxity Test / Chapter 2.2.4.1 --- MTT Assay --- p.29 / Chapter 2.2.4.2 --- Tritiated Thymidine Incorporation Assay --- p.29 / Chapter 2.3 --- Methods / Chapter 2.3.1 --- Cell Culture --- p.30 / Chapter 2.3.2 --- Direct Cytotoxicity/Cytostatic Test / Chapter 2.3.2.1 --- MTT Assay --- p.31 / Chapter 2.3.2.2 --- Tritiated Thymidine Incorporation Assay --- p.32 / Chapter 2.3.3 --- Statistical Analysis --- p.32 / Chapter 2.4 --- Results / Chapter 2.4.1 --- The Cytotoxic Effect of Pheophorbide a --- p.34 / Chapter 2.4.2 --- The Combine Effect of Pheophorbide a with 17-β Estradiol and Tamoxifen Citrate --- p.34 / Chapter 2.5 --- Discussions --- p.48 / Chapter CHAPTER THREE: --- Mechanistic Study of Pheophorbide a / Chapter 3.1 --- Backgrounds --- p.53 / Chapter 3.2 --- Materials / Chapter 3.2.1 --- Real time PCR / Chapter 3.2.1.1 --- General Chemicals and Equipments --- p.54 / Chapter 3.2.1.2 --- RNA isolation --- p.55 / Chapter 3.2.1.3 --- Reverse Transcription --- p.55 / Chapter 3.2.1.4 --- Real Time PCR --- p.56 / Chapter 3.2.2 --- Western Blotting / Chapter 3.2.2.1 --- Microsome Isolation --- p.58 / Chapter 3.2.2.2 --- Measurement of Protein Concentration --- p.58 / Chapter 3.2.2.3 --- Western Blotting --- p.58 / Chapter 3.2.3 --- Estrogen Metabolism Assay / Chapter 3.2.3.1 --- Chemicals --- p.59 / Chapter 3.2.3.2 --- Estrogen Metabolites Extraction --- p.60 / Chapter 3.2.3.3 --- Liquid Chromatography/Mass Spectrometry --- p.60 / Chapter 3.3 --- Methods / Chapter 3.3.1 --- Real time PCR / Chapter 3.3.1.1 --- Cell Culture --- p.61 / Chapter 3.3.1.2 --- RNA Isolation and Reverse Transcription --- p.61 / Chapter 3.3.1.3 --- Real Time PCR --- p.62 / Chapter 3.3.2 --- Western Blotting / Chapter 3.3.2.1 --- Cell Culture --- p.63 / Chapter 3.3.2.2 --- Microsome Isolation --- p.63 / Chapter 3.3.2.3 --- Measurement of Protein Concentration --- p.64 / Chapter 3.3.2.4 --- Western Blotting --- p.64 / Chapter 3.3.3 --- Estrogen Metabolism Assay / Chapter 3.3.3.1 --- Preparation of Calibration Standard --- p.65 / Chapter 3.3.3.2 --- Cell Culture --- p.66 / Chapter 3.3.3.3 --- Estrogen Metabolites Extraction --- p.66 / Chapter 3.3.3.4 --- Liquid Chromatography/Mass Spectrometry --- p.67 / Chapter 3.3.4 --- Statistical Analysis --- p.68 / Chapter 3.4 --- Results --- p.69 / Chapter 3.5 --- Discussions --- p.80 / Chapter CHAPTER FOUR: --- Overall Conclusion and Future Directions / Chapter 4.1 --- Significance of the Study --- p.87 / Chapter 4.2 --- Overall Conclusion --- p.87 / Chapter 4.3 --- Limitation and Difficulties of the Study --- p.89 / Chapter 4.4 --- Future Directions --- p.89 / Appendices / "Appendix I The Melting Curve of real time PCR for β-actin, CYP1A1 and CYP1B1" --- p.92 / Appendix II The Calibration Curve of BSA for Protein Concentration Measurement --- p.93 / Appendix III The Representative Peak of Estradiol Metabolite Standards with corresponding Retention Time --- p.94 / Appendix IV The Calibration Curve of Different Estrogen Metabolites for LC/MS --- p.95 / Appendix V The Accuracy and Precision of Quality Control of Estradiol Metabolites --- p.96 / Bibliography --- p.97

the majority of patients with early breast cancer receive some form of systemic adjuvant therapy (chemo-, endocrine, and/or targeted therapy). Despite the increase in adjuvant therapy prescription, little progress has been made with respect to assisting oncologists to determine which breast cancer patients, particularly those deemed at “lower risk” of relapse, require chemotherapy or other systemic therapy and which women can safely be treated with loco-regional treatment alone. For these reasons, the identification of prognostic and predictive markers that will assist the clinician in selecting the most suitable form of medical therapy has become very high priority as well as a real challenge in translational research. <p>\ / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

Thesis (MSc (Radiography))--Cape Peninsula University of Technology, 2018 / Background: Breast cancer is one of the most commonly diagnosed among woman in South Africa, and a more resilient effort should be focused on treatment improvements. Worldwide, proton therapy is increasingly used as a radiation treatment alternative to photon therapy for breast cancer, mostly to decrease the risk for radiation-induced cardiovascular toxicity. This in vitro study aims to determine a better understanding of the radiosensitivity of both tumour and normal breast cell lines to clinical proton irradiation. In addition, we propose to investigate whether the increase in linear energy transfer (LET) towards the distal part of the proton beam results in an increase in relative biological effectiveness (RBE) for both cell lines. Methods: Malignant (MCF-7) and non-malignant (MCF-10A) breast cells were irradiated at different water equivalent depths in a 200 MeV proton beam at NRF iThemba LABS using a custom-made Perspex phantom: the entrance plateau, 3 points on the Bragg peak, the D80% and the D40%. A cytokinesis-block Micronucleus (CBMN) assay was performed and Micronuclei (MNi) were manually counted in binucleated cells (BNCs) using fluorescent microscopy. Reference dosimetry was carried out with a Markus chamber and irradiations were performed with a clinical proton beam generated at NRF iThemba LABS that was degraded to a R50 (half-value depths) range of 120 mm, with a field size of 10 cm x 10 cm and a 50 mm SOBP. The phantom could be adjusted to accommodate different perspex plates depending on the depth required within the proton beam. Cells were then exposed to 0.5, 1.0, 2.0, 3.0 and 4.0 Gy doses for each cell line independently and for each dose point. Results and Discussion: For the CBMN results, a program was developed on Matlab platform to calculate the 95% confidence ellipse on the co-variance parameters α and β. These values were determined by fitting the linear quadratic dose response curve to the average number of radiation induced MNi per 1000 BN cells. The ellipse region around a coordinate (the average MN frequency) for both MCF-7 and MCF-10A cells at the plateau region was defined by the mean estimate of the α-value and the β-value that were plotted on the X-axis and Y-axis respectively. The ratio of the two parameters, α/β, is a measure of the impact of fractionation to determine the biological effective dose. In fractionated proton therapy, the MCF10A cells will repair less between two fractions compared to the MCF7 cells. This is not an indication of therapeutic gain from a fractioned treatment protocol. For this reason, the hypofractionated stereotactic treatment protocols that can be applied with protons could be to the befit of the breast cancer patient. The above argument is based only on the radiosensitivity of the two cell lines exposed in the plateau region. Further analysis of the 95% confidence ellipse of both cell lines also showed a clear increase of the alpha value toward the distal portion of the beam and indicates an increase in energy transfer in this region. The gradual increase in α and β parameters with depth for protons for both cells is of clinical importance, since it implicates a non-homogeneous dose within the targeted area and an unwanted high dose behind the targeted area. Distal energy modulation could be investigated especially with larger breast tumours. RBE was calculated as the ratio of the dose at the different positions to the dose at the entrance plateau position (reference) to obtain an equal level of biological effect. A statistically significant difference in radiosensitivity could be observed between malignant and non-malignant cells at all positions (p<0.05). The variation in RBE was between 0.99 to 1.99 and 0.92 to 1.6 for the MCF-7 and MCF10A cell respectively. Conclusions: There is a variation in RBE along the depth-dose profile of a clinical proton beam. In addition, there is difference in radiosensitivity between the cancerous cells and the normal breast cells. While this study highlights a variation in sensitivity between cells it could be used by the modelling community to further develop biologically motivated treatment planning for proton therapy.

Chemotherapy persists as one of the mainstays of breast cancer treatment, particularly for triple-negative breast cancer which currently has no targeted treatment methods. While chemotherapy is beneficial for killing the malignant tumor cells, it leads to the release of damage-associated molecular patterns into the tumor microenvironment. Damage-associated molecular patterns are a contributing factor to cancer-related inflammation which can potentiate metastatic spread through several mechanisms such as the development of tumor microenvironments at metastastic sites. These damage-associated molecular patterns include nucleic acids, nucleic acid-associated lipids and vesicles, cytokines, and proteins such as high mobility group protein B1. Polyamidoamine (PAMAM) is a biodegradable, water-soluble dendrimer polymer with the ability to possess different charges and sizes depending on its terminal branches and degree of branching (i.e. generation number), respectively. Amine-terminated PAMAM-NH2 is positively charged and can bind to circulating DNA and RNA. Since most DAMP molecules are negatively charged, I hypothesized that a polycation such as PAMAM-NH2 would be an efficient nanomaterial to remove pathogenic NA DAMPs generated by chemotherapy. Building on this dendrimer, we synthesized modified cationic PAMAM-generation 3 derivatives with an aim to balance toxicity with NA-binding affinity and capacity to encapsulate chemodrugs. Our results found that these soluble and nanoparticle PAMAM materials can bind to both cell-free DNA and RNA released as a result of treating triple-negative breast cancer cells with chemotherapy drugs such as doxorubicin and paclitaxel. These PAMAM-G3 materials are termed as nucleic acid binding polymers and nucleic-acid binding polymeric nanoparticles.My thesis dissertation explores the anti-metastatic effects of nucleic-acid binding polymeric nanoparticles delivering the chemotherapy drug paclitaxel using in-vitro and in-vivo models. Two murine metastatic breast cancer models served as the basis for assessing the effects of conventional paclitaxel delivery compared to paclitaxel delivery from within PAMAM nucleic-acid binding polymeric nanoparticles with respect to primary tumor growth, extent of lung metastasis, and the systemic inflammatory response reflected in murine serum. Compared to treatment with unencapsulated paclitaxel, delivery of paclitaxel within the PAMAM nucleic-acid binding polymeric nanoparticles resulted in significantly decreased serum cell-free DNA levels, decreased inflammatory cytokines, and a lower degree of lung metastasis in the mice. The decrease in the degree of lung metastasis in mice receiving paclitaxel within the PAMAM nanoparticles was confirmed by assessing the photon flux signal of 4T1-luciferase breast cancer cells invading the murine lungs in both in-vivo and ex-vivo imaging and by using a machine learning method to quantify the degree of metastasis in H&E- stained sections of the lungs. The ability to mitigate the phenomenon of chemotherapy-induced cancer metastasis while effectively delivering the chemotherapy to the tumor microenvironment could help improve the outcomes of patients being treated with chemotherapy. This work developed a therapeutic cationic PAMAM nanocarrier-based strategy to inhibit paclitaxel-induced metastasis by scavenging cell-free nucleic acids and mitigating cell-free nucleic acid-induced inflammation.

Treatment outcomes of young patients with invasive breast cancer treated radically at Groote Schuur Hospital from 2013 to 2017: A single centre study Background: Breast cancer is the leading cause of cancer- related deaths globally, and the commonest cancer in women under 40 years. There is currently a lack of data relating to treatment outcomes of young women with breast cancer particularly in low-and middle-income countries. Aim: This study aims to evaluate the treatment outcomes of young patients (under 40 years) treated radically for invasive breast cancer in a low-and middle-income setting. Settings: Groote Schuur Hospital, Cape Town, South Africa Methods: A retrospective review of 101 women under 40 years, with invasive breast cancer treated radically, between 2013 and 2017 was conducted. Patient characteristics, tumour characteristics, disease stage, treatment, and follow-up were recorded. Primary objectives included evaluating overall and disease free survival, and analysing recurrence patterns and clinicopathological features. Results: The five-year overall and disease free survival for the entire cohort was 77% and 51%, respectively. Five-year overall survival by molecular subtype showed that Luminal A had the best survival, while triple negative breast cancer had the worst overall survival. Conclusion: Young women with breast cancer have poor survival outcomes despite early presentation. There is limited data regarding breast cancer treatment outcomes in patients under forty years.

Thesis (D. Tech.) -- Central University of Technology, Free State, 2009 / Superficial cancerous lesions are commonly treated through low energy X-ray or electron radiation in radiotherapy. The treatment units that produce the radiation are equipped with square, rectangular and round applicators of different sizes. These applicators attach to the treatment units and define the radiation field size applied during treatment. An applicator is chosen to fit the shape of the cancerous lesion on the patient as closely as possible. Since cancerous lesions are irregular in shape, there will always be an area of healthy tissue between the edge of the lesion and the edge of the standard field shape. This healthy tissue will be irradiated along with the lesion during treatment which is undesirable since the cancer wound heals through reparative growth of the surrounding healthy tissue after treatment. Traditional techniques that were developed to shield this healthy tissue and thus shape the radiation field to the shape of the lesion present various shortcomings. This study introduces a new thermal-spray process for producing radiation field shaping shields which overcomes most of the shortcomings encountered with the traditional field shaping techniques. Since none of the commercially available thermal-spray equipment could be used to produce field shaping shields, new thermal-spray equipment was designed and fabricated tailor made to the application. Different techniques to determine the contours of the treatment area on the patient were investigated. These included a patient contact technique using a plaster bandage impression and a non-contact technique using 3D laser scanning. From the plaster bandage impression a plaster model can be produced onto which a high density low melt material such as Wood’ s alloy can be thermally sprayed to produce a field shaping mask. A model can also be produced from the 3D laser scanning data through laser sintering (LS) in nylon polyamide powder or through computer numerical controlled (CNC) milling in a block of low density polyurethane. The thermal-spray technique was evaluated by comparing the field shaping ability of radiation shields produced through the technique to the field shaping ability of shields produced through the traditional techniques. Radiographic film was used for this purpose and the results are presented in the form of isodensity charts. The required thicknesses of thermal-sprayed field shaping masks to shield radiation of various energies were also determined. The thicknesses were determined through radiation transmission measurements of known thicknesses of sprayed sheets of Wood’ s alloy. X-ray imaging showed that there were no defects present within thermal-sprayed layers of Wood’ s alloy that may negatively affect the shielding ability of masks produced through the technique.

Eighty-two patients with breast cancer, twenty-seven patients with nasopharyngeal carcinoma and sixty-five patients with rheumatoid arthritis in this study were selected based on voluntary, randomization and double blind grouping criteria. / In nasopharyngeal carcinoma patients, the decrease in percentage and the absolute count of T lymphocytes in the TCM group was significantly lower than those in the placebo group. Besides, the decrease of the absolute count of T helper and T suppressor in the TCM group was significantly lower than that in the placebo group (all p &lt; 0.05). The decrease may be due to radiotherapy. However, there was no significant difference in plasma sIL-2R and soluble tumor necrosis factor receptor 2 (sTNFR2) between the TCM group and the placebo group. / In rheumatoid arthritis patients, there was no significant difference in plasma. C-reactive protein (CRP), in the percentage, absolute count, and the ratio of CD4+/CD8+/NK/B lymphocytes between the TCM group and the placebo group. / Results showed that the absolute count of T helper lymphocytes (CD4+), the ratio of T helper lymphocytes (CD4+)/T suppressor and cytotoxic lymphocytes (CD8+), and the percentage and the absolute count of B lymphocytes were significantly elevated in the patients with breast cancer after taking Yunzhi-Danshen capsules, while plasma soluble interleukin-2 receptor (sIL-2R) concentration was significantly decreased (all p &lt; 0.05). / This study shows that the selected traditional Chinese medicine have determinable immunomodulatory effects in patients with cancer and rheumatoid arthritis. (Abstract shortened by UMI.) / Traditional Chinese medicine (TCM) has been used to treat chronic diseases and tumor allegedly by immunomodulatory mechanisms. Breast cancer and nasopharyngeal cancer are prevalent carcinoma diseases in Hong Kong. The immune system of such patients could be adversely affected during the course of conventional chemotherapy or radiotherapy. Rheumatoid arthritis is an inflammatory autoimmune disease of the joints. The aim of this study was to assess the immunomodulatory effects of TCM Yunzhi-Danshen in auxiliary treatment of both kinds of cancer patients, and Lingzhi (Ganoderma Lucidum)-San Miao San ( Atractylodes lancea, Phellodendron amurense and Achyranthes bidentata B1) in supplementation treatment of patients with rheumatoid arthritis. / by Bao Yixi. / "July 2005." / Adviser: Wai-Kei Lam. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0166. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 150-167). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Breast cancer is a global public health problem since it is the most frequently diagnosed cancer in women in Western countries. Clinical guidelines for breast cancer prognosis/diagnosis are currently based on tumour size, histological type and grade, lymph node status as well as the expression of various cellular receptors. Yet, current predictions remain unsatisfactory to identify the best treatment for the individual patient. The search for identifying new predictive and prognostic factors is ongoing. Furthermore, compelling evidences have solidified the notion that the evolving epithelial cells, founders of the breast disease, are helped in their malignant course by the tumour microenvironment. Better characterizing the dual effect of the immune regulation but also the epithelial-stromal cross-talk on both tumour-promotion and -suppression is essential for understanding patient uniqueness and their implication in disease outcome. Because of its potential to probe tissues and cells at the molecular level without requirement for extrinsic contrast agents, infrared spectroscopy was seen as an attractive tool for clinical and diagnostic analysis in order to complement the existing methods. <p>In a first step, recording and processing methodology had to be defined in order to optimally compare IR spectra. The methodology developed and the analysis tools tested on carcinoma cell lines, demonstrated that spectra could be distinguished based on the cell line phenotypic nature. <p>The potential of IR imaging for breast tissular structure differentiation was highlighted in this thesis, demonstrating that spectral signature can be correlated with the major histological cell types observed in breast disease tissues. In order to develop a robust algorithm translating spectral data into helpful histopathological information, a spectral database of histologically well-defined breast tissues was built and used for the development of a cell type classifier. This latter one was extensively validated on independent clinical cases. Firstly, the IR-based histopathological classifier correctly assigned spectra acquired on eleven breast disease samples based on their histological nature. Secondly, lymphocyte and Collagen & Fibroblasts spectral signatures were demonstrated to be independent from tissue type and organ since, although trained on reference spectra recorded into breast disease samples, the cell type classifier correctly assigned spectra acquired on lymph nodes/tonsils and scar tissues respectively. Thirdly, we concluded that spectroscopically, breast carcinoma cell lines in culture are well-suited tumour models since spectra acquired on these carcinoma cell lines were correctly recognized as epithelium by the IR-based histological classifier. <p>By spectral characterizing lymphocytes from lymph nodes and tonsils, we demonstrated that the spectra acquired contained enough information to statistically discriminate them according to their lymphocyte activation states. Although considered as activated, the breast disease lymphoid infiltrates were found to present distinct spectral signature from lymphocytes acquired on activated lymph nodes and tonsils. Furthermore, tumour microenvironment, characterized by IR-imaging was demonstrated to exhibit a distinct spectral signature from wound healing tissues. These studies proved the uniqueness of the signature of both lymphoid infiltrate and tumour microenvironment in breast disease context. Correlating these specific spectral signatures to patient outcome and therapeutics response could help better consider the uniqueness of the patient. In a last step, considering the epithelial signature of carcinomas of both low and high grades, we demonstrated that the biochemical information reflected in the IR micro-spectra was clinically relevant for grading purpose.<p><p> <p><p>Le cancer du sein est le cancer le plus fréquemment diagnostiqué chez les femmes dans les pays occidentaux. Jusqu’à peu, les cellules épithéliales tumorales étaient vues comme les seuls acteurs de la carcinogenèse ;processus se déroulant dans un milieu extracellulaire considéré au pire comme passif ou permissif à l’évolution tumorale des cellules épithéliales adjacentes. Cependant, de nombreuses études ont montré que ce microenvironnement tumoral pouvait soit promouvoir le processus de carcinogenèse soit le combattre empêchant par la même, l’occurrence de la maladie. <p>Ce projet de thèse s’inscrit dans une problématique actuelle, à savoir une meilleure compréhension de la maladie mais également une prise en charge plus individualisée des patientes. Nous abordons ici une voie de recherche novatrice basée sur la signature globale des molécules cellulaires via leur spectre infrarouge. La technologie utilisée, à savoir la spectroscopie infrarouge, nous fournit une observation quantitative et qualitative de milliers de vibrations moléculaires. L’adaptation de réseaux de plusieurs milliers de détecteurs indépendants aux microscopes infrarouges permet, grâce aux méthodes statistiques multivariées, d’investiguer l’architecture macromoléculaire des cellules au sein d’une coupe tissulaire et de corréler les informations spectrales ainsi obtenues à l’histopathologie des tissus. Par cette technologie, nous visons à mettre au point un outil diagnostique et pronostique pour le cancer du sein basé sur l’imagerie IR. <p>Durant ce projet, nous avons montré que les différents types cellulaires observés dans les carcinomes mammaires pouvaient être distingués par le biais de leur spectre IR, qu’un modèle de reconnaissance histologique pouvait être construit, validé et surtout automatisé et que ce modèle pouvait être transposé à l’étude d’autres tissus (ganglions, amygdales et cicatrices) et d’autres types d’échantillons (cellules épithéliales en culture). Nous avons également montré que les spectres de cellules épithéliales pouvaient être corrélés au grade histopathologique de la tumeur. Les spectres acquis de ganglions/amygdales ont montré que les profils spectraux pouvaient être corrélés à l’état d’activation lymphocytaire. De plus, l’étude de l’état d’activation lymphocytaire et fibroblastique a permis de mettre en avant un profil spectral propre et bien distinct des infiltrats lymphocytaires d’une part et de la matrice extracellulaire aux abords des tumeurs invasives d’autre part. <p> / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished

Indiana University-Purdue University Indianapolis (IUPUI) / Resveratrol has been shown to inhibit cell growth and induce apoptosis, as well as augment chemotherapeutics and irradiation in multiple cancer types. However, it is unknown if resveratrol is beneficial for treating drug-resistant cancer cells. To study the effects of resveratrol in triple negative breast cancer cells that are resistant to the common cancer drug, paclitaxel, a novel paclitaxel-resistant cell line was generated from the MDA-MB-231 breast cancer cell line. The resulting cell line, MDA-MB-231/PacR, exhibited a 12-fold increased resistance to paclitaxel but remained sensitive to resveratrol treatment. Resveratrol treatment reduced cell proliferation and colony formation and increased senescence and apoptosis in both the parental MDA-MB-231 and MDA-MB-231/PacR cell lines. Importantly, resveratrol treatment augments the effects of paclitaxel in both cell lines. The expression of the drug efflux transporter gene, MDR1, and the main metabolizing enzyme of paclitaxel gene, CYP2C8, was increased in the resistant cells. Moreover, pharmacological inhibition of the protein products of these genes, P-glycoprotein and CYP2C8, decreased paclitaxel resistance in the resistant but not in the parental cells, which suggests that the increase of these proteins are important contributors to the resistance of these cells. In conclusion, these studies imply that resveratrol, both alone and in combination with paclitaxel, may be useful in the treatment of paclitaxel-sensitive and paclitaxel-resistant triple negative breast cancers.