京都大学 / 新制・課程博士 / 博士(医学) / 甲第23785号 / 医博第4831号 / 新制||医||1057(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 伊達 洋至, 教授 中本 裕士, 教授 鈴木 実 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(薬科学) / 甲第25230号 / 薬科博第192号 / 新制||薬科||21(附属図書館) / 京都大学大学院薬学研究科医薬創成情報科学専攻 / (主査)教授 掛谷 秀昭, 教授 樋口 ゆり子, 教授 二木 史朗 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第25492号 / 医博第5092号 / 新制||医||1073(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 斎藤 通紀, 教授 浅野 雅秀, 教授 柊 卓志 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Overall, this study enhances our understanding of the role of c-Myc activation in chromosome 11 repositioning in mouse PreB v-abl/myc cells and a possible interaction between telomeres, TRF2, and lamin A/C underlying this phenomenon. Additionally, the importance of human 17q25.3 is confirmed as a potential region involved in NSCLC tumorigenesis. A utilizationof the 3D telomeric organization profiles is demonstrated a tendency to categorize NSCLC patients into different prognostic subgroups, underscoring a potential future value of its clinical application. / February 2017

To improve relatively poor outcomes for locally-advanced lung cancer patients, many current efforts are dedicated to minimizing uncertainties in radiotherapy. This enables the isotoxic delivery of escalated tumor doses, leading to better local tumor control. The current dissertation specifically addresses inter-fractional uncertainties resulting from patient setup variability. An automatic block-matching registration (BMR) algorithm is implemented and evaluated for the purpose of directly localizing advanced-stage lung tumors during image-guided radiation therapy. In this algorithm, small image sub-volumes, termed “blocks”, are automatically identified on the tumor surface in an initial planning computed tomography (CT) image. Each block is independently and automatically registered to daily images acquired immediately prior to each treatment fraction. To improve the accuracy and robustness of BMR, this algorithm incorporates multi-resolution pyramid registration, regularization with a median filter, and a new multiple-candidate-registrations technique. The result of block-matching is a sparse displacement vector field that models local tissue deformations near the tumor surface. The distribution of displacement vectors is aggregated to obtain the final tumor registration, corresponding to the treatment couch shift for patient setup correction. Compared to existing rigid and deformable registration algorithms, the final BMR algorithm significantly improves the overlap between target volumes from the planning CT and registered daily images. Furthermore, BMR results in the smallest treatment margins for the given study population. However, despite these improvements, large residual target localization errors were noted, indicating that purely rigid couch shifts cannot correct for all sources of inter-fractional variability. Further reductions in treatment uncertainties may require the combination of high-quality target localization and adaptive radiotherapy.

Le but de cette étude a été d’analyser l’intérêt de l’aérosolthérapie d’anticorps monoclonaux (AcM) dans le traitement du cancer broncho-pulmonaire non à petites cellules (CBNPC) en utilisant le cetuximab, un AcM anti-EGFR. L’expression du récepteur FcRn, essentiel dans la pharmacocinétique et la biodistribution des IgGs thérapeutiques a été étudiée dans le CBNPC. Nos résultats montrent que l’AcM peut résister aux contraintes physiques de la nébulisation. Les données de biodistribution et pharmacocinétique, obtenues dans un modèle animal, indiquent que l’Ac administré par aérosol, s’accumule de façon prolongée au niveau pulmonaire. De plus, les tumeurs chez la souris paraissent sensibles à l’aérosolthérapie avec l’AcM. Par ailleurs, le récepteur FcRn est moins exprimé au niveau transcriptionnel et protéique dans le tissu tumoral que dans le tissu sain adjacent à la tumeur dans le CBNPC. Cette altération de l’expression pourrait être due à l’hyperméthylation du promoteur de ce gène. / The project aims at determining whether aerosoltherapy is well suited for monoclonal antibodies (Mab), in Non-Small Cell Lung Cancer (NSCLC). In addition, exploration of the expression of FcRn, an IgG receptor contributing to increased half-life and biodistribution of Mab, has been studied in NSCLC. Using cetuximab, an anti-EGFR Mab, we showed that Mab resist the physical constraints of nebulization. Biodistribution and pharmacokinetic analyses, using a murine model, revealed that cetuximab is highly and durably accumulated within the lungs and slowly and weakly released into the bloodstream following airways delivery. Moreover, animal tumors seem sensitive to cetuximab aerosoltherapy. Expression analysis of FcRn at both the transcript and protein levels showed that the receptor is downregulated in NSCLC. FcRn alteration of expression in the tumor might be due to hypermethylation of the gene promoter as often found in cancer.

A dissertation submitted to the Faculty of Science, University of Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. March 2015 / Lung cancer is currently the most deadly form of cancer due to the fact that metastasis occurs in the lymph nodes making it difficult to remove by surgical means. Chemotherapy has been the most successful method of treatment, although it has been harmful to human health as a consequence of non-specific cytotoxicity. There has been, therefore, a growing interest in cancer research to develop alternative cancer treatments, which are less toxic. Currently plant-derived drugs are perceived to be more effective as they display both cytotoxic activity and are less harmful to overall human health. Thus the aim of the study was to determine the cytotoxic effects of the plant Lobostemon fruticosus on A549 cells. The IC50 of the methanol and butanol extracts of L. fruticosus were obtained at 40 μg/ml and 50 μg/ml, respectively. DNA fragmentation was observed after 48 hour exposure to treatments, indicating that the plant extracts induced apoptosis. Cell cycle analysis indicated that the plant extracts inhibited cell cycle progression at the sub-G0 phase, which indicated that the cells had undergone apoptosis. RT-PCR showed that the expression of p53 was down-regulated; however, p21 and Bax were up-regulated in all treatments. LC-MS identified that the compounds from the plant extracts are known apoptotic inducers. The results lead to the conclusion that the extracts of L. fruticosus, induce cell death in A549 cells. The plant extracts induced a p53-independent apoptotic mechanism, which was mediated by Bax and p21. Key words: Lobostemon fruticosus, camptothecin, taxol, Non-small cell lung cancer (NSCLC)

CARM1 et PRMT1 sont 2 Protein Arginine MethylTransferases (PRMTs) impliquées dans la prolifération et dérégulées dans le cancer. La dimérisation est une caractéristique commune aux PRMTs. PRMT1 et CARM1 coopèrent dans la régulation des gènes mais il n'existe pas de données concernant un hétérodimère CARM1/PRMT1. Nous avons trouvé que PRMT1 et CARM1 sont surexprimées dans le cancer du poumon non à petites cellules et dans 2 lignées d'adénocarcinomes pulmonaires, A549 et H1299. Les siPRMT1 réduisent la prolifération cellulaire et facilitent la différentiation. Les siCARM1 produisent un effet similaire mais, comme ceci a déjà été décrit, suppriment l'expression de PRMT1 en plus de celle de CARM1. Ainsi, CARM1 peut-elle réduire la prolifération par un effet direct ou en inhibant PRMT1. Ce résultant souligne l'intérêt d'étudier la formation de l'hétérodimère CARM1/PRMT1. Nous avons trouvé que dans les cellules A549, CARM1 n'est pas phosphorylée sur la sérine 228, interagit avec PRMT1, méthyle les promoteurs de 2 gènes cibles (Sox2 et Nanog) et est localisée dans le noyau. Dans les cellules H1299, CARM1 est phosphorylée sur la sérine 228, n'interagit pas avec PRMT1, ne méthyle pas les promoteurs de Sox2 et Nanog et est localisée dans le cytoplasme. L'inhibition de la kinase MAP2K3 empêche la phosphorylation de CARM1 sur la sérine 228 et restaure l'interaction CARM1/PRMT1 dans les cellules H1299. En conclusion, l'invalidation de PRMT1 réduit la prolifération dans les cancers du poumon. L'invalidation de CARM1 réduit aussi la prolifération probablement par l'intermédiaire de la suppression de PRMT1. Nous suggérons que MAP2K3 est la kinase qui phosphoryle CARM1 sur la sérine 228 et que cette phosphorylation inhibe l'interaction CARM1/PRMT1. La formation de l'hétérodimère CARM1/PRMT1 pourrait constituer un moyen pour réguler l'activité de ces 2 enzymes / PRMT1 and CARM1 are 2 Protein Arginine MethylTransferases (PRMTs) implicated in cell proliferation and deregulated in cancer. Dimerisation is a conserved feature in the PRMT family. PRMT1 and CARM1 cooperate in gene regulation but CARM1/PRMT1 heterodimer is not yet characterised. We report that, PRMT1 and CARM1 are overexpressed in non-small cell lung cancer samples and in 2 lung adenocarcinoma cell lines, A549 and H1299. siPRMT1 reduce proliferation and promote differentiation. siCARM1 yield similar consequences but, as this was previously described, suppress PRMT1 expression in addition to CARM1 expression. Thus CARM1 might reduce proliferation by a direct effect or alternatively through PRMT1 suppression. This result reinforces the interest of investigating the CARM1/PRMT1 heterodimer formation. We found that in A549 cells, CARM1 is not phosphorylated at serine 228, interacts with PRMT1, methylates the promoter of 2 target genes (Sox2 and Nanog) and is localized in the nucleus. In H1299 cells, CARM1 is phosphorylated at serine 228, does not interact with PRMT1, does not methylate Sox2 and Nanog promoters and is localized in the cytoplasm. Inhibition of the kinase MAP2K3 prevents the phosphorylation of CARM1 at serine 228 and restores CARM1/PRMT1 interaction in H1299 cells. In conclusion, we propose that PRMT1 knock-down reduces proliferation in lung cancer. CARM1 knock-down reduces proliferation probably through the suppression of PRMT1. We suggest that MAP2K3 is the candidate kinase that phosphorylates CARM1 at serine 228 and that phosphorylation inhibits CARM1/PRMT1 interaction. CARM1/PRMT1 heterodimer formation might be a way of regulating the activities of these enzymes

Pharmacological ascorbate, intravenous administration of high-dose vitamin C aimed at peak plasma concentrations ~ 20 mM, has recently re-emerged, after a controversial history, as a potential anti-cancer agent in combination with standard-of-care radiation and chemotherapy-based regimens. The anti-cancer effects of ascorbate are hypothesized to involve the auto-oxidation or metal-catalyzed oxidation of ascorbate to generate H2O2, and preclinical in vitro and in vivo studies in a variety of disease sites demonstrate the efficacy of adjuvant ascorbate. Furthermore, phase I clinical trials in pancreatic and ovarian cancer have demonstrated safety and tolerability in combination with chemotherapy and preliminary results suggest therapeutic efficacy. Both preclinical in vitro and in vivo studies as well as phase I clinical trials suggest a cell-intrinsic mechanism of selective toxicity of cancer cells as compared to normal cells; however, the mechanism(s) for cancer cell-selective toxicity remain unknown. The current study aims to investigate the preclinical therapeutic efficacy of pharmacological ascorbate in combination with standard cancer therapies in three novel disease sites: non-small cell lung cancer (NSCLC), glioblastoma multiforme (GBM), and some histological subtypes of sarcoma. In vitro experiments demonstrate cancer cell-selective susceptibility to pharmacological ascorbate as compared to normal cells of identical cell lineages. Furthermore, in vivo murine xenograft models of NSCLC, GBM, and fibrosarcoma demonstrate therapeutic efficacy of pharmacological ascorbate in combination with chemotherapy and/or radiation as compared to chemotherapy and/or radiation alone without any additional therapeutic toxicity. Additionally, a phase I clinical trial in GBM subjects demonstrates the safety and tolerability of ascorbate in combination with radiation and temozolomide therapy. Although not powered for efficacy, preliminary results suggest that ascorbate may be efficacious in these subjects (median survival 18.2 months vs. 14.6 months in historical controls), and, importantly, that ascorbate therapy may be independent of MGMT promoter methylation status (median survival 23.0 months vs. 12.7 months in historical controls with absent MGMT promoter methylation). Preliminary results from a phase II clinical trial of ascorbate in combination with carboplatin/paclitaxel chemotherapy in advanced stage NSCLC subjects also demonstrate promising preliminary results related to efficacy (objective response rate (ORR) 29% and disease control rate (DCR) 93% vs. historical control ORR 15-19% and DCR 40%). In addition to demonstrating the potential efficacy of pharmacological ascorbate in combination with standard anti-cancer therapies, this work demonstrates that the selective toxicity of ascorbate may be mediated by perturbations in cancer cell oxidative metabolism. Increased mitochondrial-derived O2- and H2O2 disrupts cellular iron metabolism, resulting in increased iron uptake via Transferrin Receptor and a larger intracellular labile iron pool. The larger pool of labile iron in cancer cells underlies the selective sensitivity of cancer cells to ascorbate toxicity through pro-oxidant chemistry with ascorbate-produced H2O2. This mechanism is further supported by the finding of increased levels of O2- and labile iron in patient lobectomy-derived NSCLC tissue as compared to adjacent normal fresh frozen tissue. Together, these studies demonstrate the feasibility, selective toxicity, tolerability, and potential efficacy of pharmacological ascorbate in NSCLC, GBM, and sarcoma therapy and propose that further investigations of tumor and systemic iron metabolism are required to determine if these alterations can be exploited to enhance therapeutic efficacy or serve as therapeutic biomarkers.

Lung cancer is the number one cause of cancer related death worldwide, with more than 1.6 million fatalities each year. Non-small cell lung cancer (NSCLC) accounts for 80-85% of all lung cancers, with KRAS being one of the most prevalent oncogenic driver mutations. Therapeutic approaches for KRAS-mutated NSCLC have been extensively explored due to the US National Cancer Institute RAS Initiative, but methods of directly targeting KRAS or downstream effectors, such as MEK, still have poor results. Previous reports have shown that KRAS-mutated NSCLC activate distinct receptor tyrosine kinases (RTKs) depending on the epithelial or mesenchymal state. Epithelial-to-mesenchymal transition (EMT) is known to play a role in the metastasis and poor prognosis of cancer, and is induced by extracellular matrix (ECM) stiffness. Hallmarks of EMT include loss of E-Cadherin and increase in Vimentin. This research investigates the role of KRAS in EMT transition due to increased ECM stiffness in KRAS mutant NSCLC, and how this affects the efficacy of KRAS and MEK inhibition. To understand how KRAS mutations in NSCLC play a role in this stiffness induced EMT, experiments were performed to detect the gene and protein expression of EMT markers, as well as possible sources of mechanosensing, including primary cilia and receptor tyrosine kinases. We hypothesized that KRAS plays a role in activation of mechanosensors and directly correlates to EMT induced by increased mechanical forces. Results show when KRAS was inhibited and there was increased mechanical forces, either from stretch or substrate stiffness, there was a decreased activation of mechanosensors. KRAS inhibition also prevented the cells from undergoing stiffness-induced EMT. This supports our hypothesis that KRAS plays a key role in ECM stiffness induced EMT. Future studies include examining the mechanism behind this phenomenon and in vivo studies.