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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Tumor growth suppression using a combination of taxol-based therapy and GSK3 inhibition in non-small cell lung cancer

O'Flaherty, L., Shnyder, Steven, Cooper, Patricia A., Cross, S.J., Wakefield, J.G., Pardo, O.E., Seckl, M.J., Tavare, J.M. 17 March 2019 (has links)
Yes / Glycogen synthase kinase-3 (GSK3) is over-expressed and hyperactivated in non-small cell lung carcinoma (NSCLC) and plays a role in ensuring the correct alignment of chromosomes on the metaphase plate during mitosis through regulation of microtubule stability. This makes the enzyme an attractive target for cancer therapy. We examined the effects of a selective cell-permeant GSK3 inhibitor (CHIR99021), used alone or in combination with paclitaxel, using an in vitro cell growth assay, a quantitative chromosome alignment assay, and a tumor xenograft model. CHIR99021 inhibits the growth of human H1975 and H1299 NSCLC cell lines in a synergistic manner with paclitaxel. CHIR99021 and paclitaxel promoted a synergistic defect in chromosomal alignment when compared to each compound administered as monotherapy. Furthermore, we corroborated our in vitro findings in a mouse tumor xenograft model. Our results demonstrate that a GSK3 inhibitor and paclitaxel act synergistically to inhibit the growth of NSCLC cells in vitro and in vivo via a mechanism that may involve converging modes of action on microtubule spindle stability and thus chromosomal alignment during metaphase. Our findings provide novel support for the use of the GSK3 inhibitor, CHIR99021, alongside taxol-based chemotherapy in the treatment of human lung cancer. / Cancer Research UK Project Grant (C16929/A14402) and the Elizabeth Blackwell Institute, through its Wellcome Trust ISSF Award (105612/Z/14/Z). The Imperial NIHR/Biomedical Research Centre and the CR-UK/Dept of Health funded Imperial Experimental Cancer Medicine Centre.
92

Flattening Filter Free photon beams for treatment of early-stage lung cancer: an investigation of peripheral dose

Mader, Joanna E. 23 December 2014 (has links)
The purpose of this thesis was to evaluate and compare the peripheral dose associated with VMAT lung SABR treatments for 10X, 6X, and 10X-FFF beams. Flattening Filter Free (FFF) radiotherapy photon beams exhibit high dose rates as compared to standard flattened photon beams. The high dose rates available with FFF beams make them ideal for high dose treatments, such as Volumetric Modulated Arc Therapy (VMAT)-delivery lung Stereotactic Ablative Radiotherapy (SABR), where treatment delivery is longer than that of standard treatments. They are also known to show reductions in treatment head scatter, multi-leaf collimator (MLC) transmission and treatment head leakage radiation, compared to flattened beams. The use of FFF beams for VMAT lung SABR has been shown to significantly reduce treatment delivery time, while maintaining plan quality and accuracy. Another potential advantage of the use of FFF beams for VMAT lung SABR is the reduction in peripheral (out-of-field) dose, due mainly to the reduction in head scatter and treatment head leakage. The peripheral doses delivered by VMAT Lung SABR treatments using 10X-FFF, 10X and 6X were investigated for the Varian TrueBeam medical linear accelerator. There were three components to this investigation; (1) Ion chamber measurement of peripheral dose for static open, static MLC and dynamic MLC fields, (2) Validation of Monte Carlo, Acuros XB and AAA algorithms for peripheral dose prediction, and (3) Evaluation of peripheral doses for VMAT lung SABR treatments using the validated Monte Carlo model. Measurements of out-of field doses for static open, static MLC and dynamic MLC fields showed that 10X-FFF delivered peripheral doses in the range of 30% to 50%, 3% to 40% and 5% to 20% lower than the peripheral doses for flattened beams. Dose calculation algorithm validation showed that AAA and Acuros XB significantly under predicted the dose in the peripheral region. Monte Carlo was found to be the most accurate dose calculation algorithm for peripheral dose prediction. The VMAT lung SABR dose distributions were calculated for both static gantry delivery and arc delivery using the validated Monte Carlo model. For static gantry Monte Carlo simulation, 10X-FFF was found to show a reduction in peripheral dose in the range of 7% to 21% and 7% to 17% when compared to 6X and 10X. For arc delivery Monte Carlo simulation, 10X-FFF was found to deliver a statistically significant reduction in mean peripheral dose compared to 6X in four of the six cases, and was not found to deliver a statistically significant reduction in mean peripheral dose compared to 10X in any of the six cases. For this type of VMAT lung SABR treatment, 10X-FFF offers a reduction in peripheral dose over 6X. In terms of the benefits of using 10X-FFF for this type of treatment, the reduction in peripheral dose is added to the already-established reduction in treatment times. / Graduate / 0756 / 0574
93

c-Myc- driven nuclear repositioning of chromosome 11 in mouse plasmacytomas and its clinical significance

Sunpaweravong, Patrapim 27 January 2017 (has links)
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
94

Automatic Block-Matching Registration to Improve Lung Tumor Localization During Image-Guided Radiotherapy

Robertson, Scott 24 April 2013 (has links)
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.
95

Etude de l’implication des récepteurs nicotiniques à l’acétylcholine dans le développement des cancers pulmonaires non à petites cellules / Study of the involvement of nicotinic acetylcholine receptors in the development of non-small cell lung cancer

Medjber, Kahina 30 January 2012 (has links)
La progression tumorale est caractérisée par deux processus clés, la prolifération et l’invasion cellulaires. Les nAChRs, activés par la nicotine et ses nitrosamines dérivées (NNN et NNK), modulent les concentrations calciques intracellulaires et activent in vitro la prolifération, l’apoptose, la migration et l’invasion de lignées cellulaires tumorales. Dans cette étude, nous montrons, en utilisant des cultures primaires de cellules dérivées de cancers pulmonaires non à petites cellules (carcinomes épidermoïdes et adénocarcinomes), que les nAChRs α7 régulent différemment la prolifération cellulaire en fonction du stade de différenciation des tumeurs. Le nAChR α7 agit comme répresseur de la prolifération cellulaire dans les tumeurs bien différenciées et dans l’épithélium respiratoire normal, alors que dans les tumeurs peu différenciées, il stimule la prolifération cellulaire en réponse à la nicotine. A l’inverse, le nAChR α3α5β2 n’est que partiellement impliqué dans la régulation de la prolifération cellulaire aussi bien dans les tumeurs pulmonaires que dans l’épithélium respiratoire normal. Les nAChRs α7 et nAChRs α3α5β2 sont tous les deux impliqués dans la stimulation de l’invasion des cellules tumorales des carcinomes épidermoïdes et adénocarcinomes. Le polymorphisme non-synonyme rs16969968 de la sous-unité α5 induit une mutation au niveau d’un acide aminé hautement conservé (D398N). De nombreuses études d’association pangénomiques lient ce polymorphisme au développement des cancers pulmonaires. Dans cette étude nous montrons que les nAChRs exprimant la sous-unité α5 mutée (D398N) altèrent la prolifération et la différenciation des cellules respiratoires et modulent l’invasion des cellules tumorales, en synergie avec les nAChRs α7. / Tumor progression is characterized by two key processes, cell proliferation and invasion. Nicotinic receptors, activated by nicotine and its derived nitrosamines (NNK and NNN) modulate intracellular calcium concentrations and activate in vitro proliferation, apoptosis, migration and invasion of tumor cell lines. In this study, we show, by using primary cell cultures from lung cancer tumors, adenocarcinoma and squamous cell carcinoma, that nAChR α7 differently regulates cell proliferation according to the state of tumor differentiation. The α7 nAChRs acts as a repressor of cell proliferation in differentiated lung cancer tissues and in the normal respiratory epithelium, while it stimulates cell proliferation in response to nicotine, in poorly differentiated tumors. Conversely, the α3α5β2 nAChR is only partially involved in the regulation of cell proliferation in lung cancers and in the normal respiratory epithelium. The α7 and α3α5β2 nAChRs are both involved in the in vitro invasion process of adenocarcinoma and squamous cell carcinoma. Non-synonymous polymorphism rs16969968 in the CHRNA5 gene induces a mutation in a highly conserved amino acid (D398N). Many genome-wide association studies have demonstrated the relationship between this polymorphism and the incidence of lung cancer. In this study, we show that nAChRs, expressing the mutated α5 subunit (D398N), are in involved in the alteration of the proliferation and the differentiation state of respiratory epithelial cells, and also modulate tumor cell invasion, in synergy with the α7 nAChRs.
96

Effet thérapeutique du cetuximab administré par aérosol dans un modèle animal de tumeur broncho-pulmonaire : importance du récepteur Fc Rn dans la réponse anti-tumorale à cet anticorps.

Maillet, Agnès 27 November 2008 (has links)
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.
97

Phytochemical screening, cytotoxicity and anticancer activity of Lobostemon fruticosus extracts on human lung cancer cell line

Ndlovu, Lungile Melly 03 1900 (has links)
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)
98

La phosphorylation de CARM1 empêche l'interaction entre PRMT1 et CARM1, deux « Protein Arginine MethylTransférases » impliquées dans la prolifération dans le cancer du poumon / CARM1 phosphorylation prevents interaction between PRMT1 and CARM1, two <<protein arginine methyltransferases>> involved in proliferation in lung cancer

Akoum, Rania El 16 October 2013 (has links)
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
99

Estratégia de planejamento e otimização do handover em redes móveis densificadas / Handover planning and optimization strategy in densified mobile networks

SILVA, Ketyllen da Costa 29 June 2018 (has links)
Submitted by Luciclea Silva (luci@ufpa.br) on 2018-09-24T13:27:16Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_Estrategiaplanejamentootimizacao.pdf: 4095042 bytes, checksum: 09ece03e5c64f31852d1972ec124912a (MD5) / Approved for entry into archive by Luciclea Silva (luci@ufpa.br) on 2018-09-24T13:28:07Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_Estrategiaplanejamentootimizacao.pdf: 4095042 bytes, checksum: 09ece03e5c64f31852d1972ec124912a (MD5) / Made available in DSpace on 2018-09-24T13:28:07Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_Estrategiaplanejamentootimizacao.pdf: 4095042 bytes, checksum: 09ece03e5c64f31852d1972ec124912a (MD5) Previous issue date: 2018-06-29 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O crescente aumento no uso de dispositivos e aplicações móveis nos últimos anos, tem levado a uma sobrecarga da infraestrutura da rede responsável pelo escoamento desse tráfego, afetando tanto o desempenho da rede quanto a experiência do usuário. As redes móveis heterogêneas já são realidade e sua densificação tem sido apontada como uma das soluções propostas para atendimento das demandas esperadas para as redes celulares de quinta geração (5G). Nas redes atuais, no entanto, ainda é comum o uso de parâmetros fixos na configuração da rede, mas esta estratégia nem sempre se mostra eficiente. É dentro deste contexto que se consolida o conceito de redes auto organizáveis nas quais os vários parâmetros da rede são ajustados automaticamente com base em medições em tempo real e sistemas inteligentes. Esta tese apresenta uma estratégia para otimização de handover em redes LTE com densa implantação de small cells. Com base em medições e lógica fuzzy são propostos algoritmos para o auto ajuste de parâmetros da rede. A partir de simulação discreta utilizando o MATLAB, os resultados são obtidos e apresentados através das principais métricas de avalição de desempenho de handover. / The increase in mobile devices and applications in recent years has led to an overload of the network infrastructure responsible for disposing this traffic, thus affecting the performance of the network as the user experience.Heterogeneous mobile networks are already a reality and their densification has been put forward as one of the suggested solutions to meet the expected demands for 5th generation (5G) mobile networks. However, in the current networks, it is still common for fixed parameters to be used for the configuration of the network although this strategy does not always prove to be efficient. It is within this context that the concept of selforganizing networks (SONs) has been established, in which several network parameters are automatically adjusted on the basis of measurements and intelligent systems in real time. This thesis presents a strategy to optimize the handover in LTE networks with dense small cells. Based on measurements and fuzzy logic new algorithms are proposed for self-tuning network parameters. From discrete simulation using MATLAB, the results are evaluated and presented through the main performance metrics of handover.
100

Impact de l’autophagie sur la radiosensibilité tumorale / Impact of autophagy on radiosensitivity of tumor cells

Ko, Adrien 29 November 2013 (has links)
Les données existantes sur le rôle de l’autophagie dans la mort cellulaire radio-induite sont controversées et proviennent d’études pour lesquelles sont utilisées des drogues : l’action se produit donc de manière indirecte. Certains suggèrent que l’induction combinée de l’apoptose et de l’autophagie améliore le traitement par radiations ionisantes. D’autres indiquent que l’induction de l’autophagie favoriserait la radiorésistance des cellules tumorales et que l’utilisation d’inhibiteurs de l’autophagie augmenterait la réponse des tumeurs aux radiations ionisantes. L'autophagie, ou «self-eating», est un processus cellulaire activé par diverses conditions de stress, par lequel les cellules peuvent dégrader les protéines et les organites. Nous avons au cours de cette étude cherché à déterminer le rôle de l'autophagie dans la mort cellulaire radio-induite. Selon nos observations, l'autophagie est nécessaire pour la libération de l'ATP après un traitement par radiothérapie: en effet, le knockdown de gènes essentiels à l'autophagie limite la sécrétion d'ATP. Nous avons également constaté que des cellules déficientes pour l'autophagie traitées par radiothérapie sont incapables d’immuniser des souris contre une injection de cellules vivantes. En outre, les tumeurs déficientes pour l’autophagie répondent moins bien à un traitement par radiations ionisantes dans des souris immunocompétentes et continuent à proliférer, contrairement aux tumeurs “wild-type”. De plus, nous avons montré que les cellules déficientes pour l'autophagie ne sont pas en mesure de recruter des cellules dendritiques dans le lit tumoral. A l'inverse, l'inhibition des enzymes de dégradation de l’ATP extracellulaire accroît les concentrations d'ATP dans les tumeurs déficientes pour l'autophagie, ce qui rétablit le recrutement des cellules immunitaires dans le lit tumoral et restaure la réponse à la radiothérapie des cancers déficients pour l'autophagie. Ainsi, cette étude a montré l'importance de l'autophagie dans la réponse anti-tumorale spécifique, après traitement par radiations ionisantes. Ces résultats ouvrent de nouvelles perspectives pour comprendre la mort cellulaire radio-induite. Il reste cependant à découvrir les mécanismes moléculaires sous-jacents pour développer de nouvelles thérapies ciblées qui amélioreront l’efficacité de la radiothérapie. / Most of the available data on autophagy and tumor response to IR comes from indirect conclusions after concomitant drug-IR exposure. Some authors suggest that concurrent induction of apoptosis and autophagy enhances radiation therapy. Oppositely, others indicate that the induction of autophagy contributes to the radioresistance of tumor cells and suggest that autophagy inhibitors may be employed to increase the sensitivity radioresistant tumors cells to ionizing radiation. Autophagy literally ‘self-eating’ is a cellular process activated in response to various conditions of cellular stress, whereby cells can liberate energy resources via the degradation of proteins and organelles. In this project we aimed to determine the potential role of autophagy in IR –induced cell death. We found that autophagy is required for the release of ATP in response to radiotherapy, as we observed that the knockdown of essential autophagy-related genes abolished its secretion. Furthermore, autophagy deficient tumors growing on immunocompetent mice did not respond to radiotherapy and continued proliferating in contrast to autophagy proficient tumors. We showed that autophagy deficient cells were neither able to recruit DCs into the tumor bed. Conversely, the inhibition of extracellular ATP degrading enzymes increased extracellular ATP concentrations in autophagy deficient tumors, which reestablished the recruitment of immune cells into the tumor bed, and restored radiotherapeutic responses in autophagy-deficient cancers.Altogether, this study showed the importance of autophagy in tumor-specific immune response after radiotherapy. Thus giving new insights into the concept of IR-induced cell death. However, there is still much that is unknown about molecular mechanisms that undergo IR-induced cell death. Understand these molecular mechanisms will help to develop new targeted therapies that will improve the effectiveness of radiotherapy.

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