921 resultados para Chinese cancer patients


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SUMMARYThe innate immune system plays a central role in host defenses against invading pathogens. Innate immune cells sense the presence of pathogens through pattern recognition receptors that trigger intracellular signaling, leading to the production of pro-inflammatory mediators like cytokines, which shape innate and adaptive immune responses. Both by excess and by default inflammation may be detrimental to the host. Indeed, severe sepsis and septic shock are lethal complications of infections characterized by a dysregulated inflammatory response.In recent years, members of the superfamily of histone deacetylases have been the focus of great interest. In mammals, histone deacetylases are broadly classified into two main subfamilies comprising histone deacetylases 1-11 (HDAC1-11) and sirtuins 1-7 (SIRT1-7). These enzymes influence gene expression by deacetylating histones and numerous non-histone proteins. Histone deacetylases have been involved in the development of oncologic, metabolic, cardiovascular, neurodegenerative and autoimmune diseases. Pharmacological modulators of histone deacetylase activity, principally inhibitors, have been developed for the treatment of cancer and metabolic diseases. When we initiated this project, several studies suggested that inhibitors of HDAC 1-11 have anti-inflammatory activity. Yet, their influence on innate immune responses was largely uncharacterized. The present study was initiated to fill in this gap.In the first part of this work, we report the first comprehensive study of the effects of HDAC 1- 11 inhibitors on innate immune responses in vitro and in vivo. Strikingly, expression studies revealed that HDAC1-11 inhibitors act essentially as negative regulators of basal and microbial product- induced expression of critical immune receptors and antimicrobial products by mouse and human innate immune cells like macrophages and dendritic cells. Furthermore, we describe a new molecular mechanism whereby HDAC1-11 inhibitors repress pro-inflammatory cytokine expression through the induction of the expression and the activity of the transcriptional repressor Μί-2β. HDAC1-11 inhibitors also impair the potential of macrophages to engulf and kill bacteria. Finally, mice treated with an HDAC inhibitor are more susceptible to non-severe bacterial and fungal infection, but are protected against toxic and septic shock. Altogether these data support the concept that HDAC 1-11 inhibitors have potent anti-inflammatory and immunomodulatory activities in vitro and in vivo.Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that plays a central role in innate immune responses, cell proliferation and oncogenesis. In the second part of this manuscript, we demonstrate that HDAC1-11 inhibitors inhibit MIF expression in vitro and in vivo and describe a novel molecular mechanism accounting for these effects. We propose that inhibition of MIF expression by HDAC 1-11 inhibitors may contribute to the antitumorigenic and anti-inflammatory effects of these drugs.NAD+ is an essential cofactor of sirtuins activity and one of the major sources of energy within the cells. Therefore, sirtuins link deacetylation to NAD+ metabolism and energy status. In the last part of this thesis, we report preliminary results indicating that a pharmacological inhibitor of SIRT1-2 drastically decreases pro-inflammatory cytokine production (RNA and protein) and interferes with MAP kinase intracellular signal transduction pathway in macrophages. Moreover, administration of the SIRT1-2 inhibitor protects mice from lethal endotoxic shock and septic shock.Overall, our studies demonstrate that inhibitors of HDAC1-11 and sirtuins are powerful anti-inflammatory molecules. Given their profound negative impact on the host antimicrobial defence response, these inhibitors might increase the susceptibility to opportunistic infections, especially in immunocompromised cancer patients. Yet, these inhibitors might be useful to control the inflammatory response in severely ill septic patients or in patients suffering from chronic inflammatory diseases.

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The Development of Radiation Oncology Services in Ireland The provision of a high quality radiation oncology service is one of the cornerstones of a modern treatment programme for cancer patients. Timely and equitable access to a radiation oncology service of the highest international standard should be available to all cancer patients in Ireland and it was the achievement of this goal that guided and motivated the group in producing this report and its accompanying recommendations. Click here to download PDF 46kb

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Tumor vaccines may induce activation and expansion of specific CD8 T cells which can subsequently destroy tumor cells in cancer patients. This phenomenon can be observed in approximately 5-20% of vaccinated melanoma patients. We searched for factors associated with T cell responsiveness to peptide vaccines. Peptide antigen-specific T cells were quantified and characterized ex vivo before and after vaccination. T cell responses occurred primarily in patients with T cells that were already pre-activated before vaccination. Thus, peptide vaccines can efficiently boost CD8 T cells that are pre-activated by endogenous tumor antigen. Our results identify a new state of T cell responsiveness and help to explain and predict tumor vaccine efficacy.

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NICaN Regional Supportive & Palliative Care Network Friday 30th May 2008 Lecture Theatre, Fern House Antrim 2.00 pm - 5.00 pm Welcome, Introductions Stuart MacDonnell, Chair of the Supportive and Palliative Care network welcomed everyone to the meeting. This meeting had been rescheduled to accommodate the validation workshop for the regional palliative care model, which took place on Friday,18th April. Acknowledging the full agenda, several items were pulled forward to accommodate speakers SPC_0809_03 Modernisation and Reform of Supportive and Palliative care Mr MacDonnell welcomed Dr Sonja McIlfatrick and Dr Donna Fitzimons, members of the Phase 1 Project Team for the Modernisation and Reform of palliative care. Their presentation highlighted the journey taken by the Project Team since January 2008 - May 2008. Seeking to deliver the network vision, for any person with palliative care need, cancer or non - cancer, the project team incorporated several methodologies. The literature review identified best practice. An assessment of need including epidemiological data and review of service provision. Consultation reflected the engagement with patients, carers and professional forums, primary care and non-malignant focus groups. The breadth of consultation confirmed the evidence for the identified components of the model. These were validated at the April workshop. External review of the work was provided by Dr Phil Larkin (Galway Uni) Prof David Clark (End of Life Care Observatory, Lancaster University) and Mr Bob Neillans (Chair of the Mid Trent Palliative care network, which has been involved in the Delivering choice programme within Lincolnshire). The Guiding Principles of the model reinforced Patient and family centred care, enhanced community provision and supported by specialists. The components of the model are · Identification of patient with Palliative careened · Holistic Assessment · Integration of services · Coordination of care · End of Life Care and Bereavement Care The consultation process also highlighted the need for Increased Public and Professional Awareness. This was recognised as an encompassing component. Underpinning the model is the need for robust Education and common core values e.g. dignity, choice, advocacy, empowerment, partnership working. Stuart MacDonnell, who also chaired the steering group during the project, congratulated the Project Team for delivering the comprehensive document on schedule. The Report has been submitted to the NICaN Board and the DHSSPSNI. In addition, an outline for Phase 2 of this work has been submitted. Mr MacDonnell recognised that there is real opportunity for palliative care to benefit from the DHSSPSNI commitment to concrete developments. Phase 2 will progress the current high-level components of the model into quality services developments at a local level, demonstrating integration throughout. The methods propose continued engagement with the Delivering Choice Programme enabled through a Central and also Local Teams. The report and the Appendices care available on the NICaN website www.nican@n-i.nhs.uk SPC_0809_01 Chairman's Business · Update on the Cancer Service Framework, the document has been submitted and presented to the Departmental Programme Board. Next stages will include the review of costs and development of a implementation guidance It is hoped that the completed document should be available for public consultation in Autumn 2008. with a launch of the framework document and accompanying implementation guide in Spring 2009. Some funding has already been identified to advance key areas of work including, Advanced communication skills training, peer review and an appointment of a post to develop the cancerni.net, focusing on children and e-learning tools. · Children's and Adolescent Cancer network group , Liz Henderson is to convene a group to consider how this is to be taken forward. · NICaN appointments Recognition was given to the significant contribution made by Dr Gerard Daly during his position as NICaN Lead Clinician, particularly throughout the early establishment of the NICaN. Dr Dermott Hughes (Western Trust) has been appointed as the NICaN Medical Director. The Primary Care Director post has been advertised and it is hoped that the Director of Network will be advertised later in Summer. Endorsement of End of Life care paper. The Paper was presented and endorsed at the March 2008 NICaN Board meeting. Mr David Galloway (Director of Secondary Care) emphasised the need for this important work to be recognised within the regional model to ensure that it is reflected in future models of service delivery Congratulations were again echoed to the Chair of the End of Life Group for this work, Dr Glynis Henry, and the working group Other recognition Mr MacDonnell congratulated the significant achievements across the network. These include: · Dr Francis Robinson (Consultant Palliative Medicine, Western Trust) Awarded - Consultant of the year at the NI Health Care awards. · Mrs Evelyn Whittaker Hospice Nurse Specialist, NI Hospice, Joint Second Prize in the Development award within the International Journal of Palliative Nursing Awards, for her work in development of palliative care education in nursing homes. · Mr Ray Elder is the newly appointed Team Leader of Community Palliative care, SE Trust. · Mrs Bridget Denvir, who managed the establishment of one of the first community multiprofessional palliative care teams is moving to work with establishing integrated teams within the Belfast Trust. Bridget has been an active core member of the network and here contribution has been much appreciated. Mrs Sharon Barr will attend in future. SPC_0809_02 Minutes & matters Arising from Meeting, 13th December 2007 No amendments were made to the draft minutes from the December meeting. These will be posted on the NICaN website for future reference. Palliative Care Research Following consultation, the response to the business case for the All Ireland Institute was forwarded on 22 February 2008 to Prof David Clark. Prof Judith Hill informed the group that terms of tender are now being developed. Awareness raising across academic institutions continues to engage interest in potential partnerships. Atlantic Philantrophies have offered financial support to the venture and match funding is being sought from across jurisdictions. Previous discussions at Network meetings have endorsed the need to establish a work strand for research and development within palliative and end of life care. To identify the body of interested parties and explore the strengths and weaknesses of a collaborative model for research, a workshop, - Building collaboration for Palliative and End of life Care Research -will take place on 4 June 10am - 2pm.in the Comfort Hotel.Antrim, The workshop will be chaired by Prof David Clark, Director of the International Observatory on End of Life Care. Prof Shelia Payne, Help the Hospices Chair in Hospice Studies and co director of the Cancer Experiences Collaborative will present the Experiences and Results from Research Collaborative. Feedback from this event will be brought back to the next meeting in September. SPC_0809_04 Patient Information pathways - a pathway for advanced disease Ms Danny Sinclair, NICaN Regional Coordinator for Patient Information informed the network of how patient information pathways have been developed in line with the Cancer Services Collaborative. Emerging themes, with regard to information needs of patients with advanced disease, are being identified from the work undertaken across the tumour groups. It is important to identify all information needs to develop a generic pathway of information resources for advanced disease to be endorsed by the Supportive and Palliative care network. This could be used across the all tumour specific information pathways and across organisational boundaries. The resulting pathway could potentially be used for non- cancer condition. A group is to be established to take this work forward. The group will: · Develop a list of advanced disease information themes · .Identify when they become relevant for the patient or their carer · .Identify existing resources · .Develop resources where needed · .Participate or nominate when review is required Dr Sheila Kelly nominated Helen Hume (SETrust) Paula Kealey will also contribute to this work; a nomination from the Patient and Public Information Forum has also been identified. A date will be circulated across the network to engage further interest and establish group SPC_0809_08 Development of a Regional Syringe Driver Prescription Chart Ms Kathy Stephenson reported that the second consultation of the draft regional syringe driver prescription chart and the focus group discussions, Pilots of the chart are to be undertaken within Trust, Hospices and General Practices. SPC_0809_05 A framework for Generalist and Specialist Palliative and End of Life Care Competency Dr Kathleen Dunne, lead of the Education works strand, reported on the findings following consultation of the Education framework. The report was widely appreciated across the network and valued as a significant and timely document for the commissioning of generalist and specialist adult palliative care education. Mr MacDonnell congratulated Dr Dunne and the members of the education workstrand for developing the framework aligning its significance to the underpinning needs of the regional model Amendments will be made to the document and then forwarded to the NICaN Board for endorsement. A process of implementation will be explored and reported to the network group at the September meeting. Key target areas for generalist palliative care education were highlighted within care of the elderly and general medicine. . SPC_0809_06 Pallcareni.net-a website for people with palliative care needs Ms Danny Sinclair, reminded the group of the pending amalgamation of the CAPriCORN and NICaN website. The resulting new web address will be www. cancerni.net. Recurrent funding has been secured to ensure the development of the supportive and palliative care website.www.Pallcareni.net The new website will host good information for people with palliative care needs, regardless of diagnosis. It will be accessible via the cancerni.net portal or independently as the pallcareni portal. It will signpost people with palliative care needs to condition- specific websites. The website will also enable the communication needs of the NI Regional Supportive & Palliative Care Network. This is a very significant method of seeking to enable greater understanding of palliative care for public and professionals, as highlighted within the regional model. Currently the material from the CAPriCORN website is being migrated onto cancerni and /or pallcareni.net as appropriate. To enable the further development of this opportunity a steering group of interested individuals is to be established. Their role will be to: · Drive the development of the website so it meets the needs of public and professionals through the sourcing and development of additional content · Identify any support that is needed, e.g. technical support · Review the website as a whole as it grows (coordinating condition-specific developments) · Review the functions of the website to aid communication throughout the Supportive and Palliative care network The steering group representation should reflect the constituencies within the Supportive and Palliative Care network. Current expressions of interest have come from Heather Reid and Valerie Peacock. A date will be circulated across the network to engage further interest and establish group SPC_0809_07 Update of Guidelines workstrand Dr Pauline Wilkinson presented the current work within the guidelines workstrand. 1. Brief Holistic Assessment & Referral Criteria to Specialist Palliative Care The development of an Holistic assessment Tool will help to identify holistic need at generalist and specialist level. Recognition of complex need prompts appropriate referral to specialist palliative care. The regional referral form is compatible with the Minimum Data set. The final drafts of this work are to be circulated widely, inclusive of service framework groups, primary care, secondary care and the supportive and palliative care network. Consultation will take place during June and July. Piloting of the forms will also be undertaken. 2. Control of Pain in Cancer Patients The original guidelines where developed 2003 and are now ready for review. The Mapping exercise, undertaken in May 2007, highlighted that the Guidelines were poorly adopted. The group have reviewed the pending SIGN 2 guidelines for pain with regard to practice in Northern Ireland. These are highly evidence based and are due to be launched this Summer. Whilst an excellent resource their comprehensiveness limits their readability, this may result in poor compliance. The Guidelines group feel it is important to have accessible and user-friendly guidelines particularly for Generalists and Out of hours. There are examples of good work that has taken place across the province, but there is a need for regional consistency. Dr Wilkinson has contacted Dr Carolyn Harper (Deputy CMO) and GAIN with regard to enabling funding to progress this work. The Guidelines group hope to approach the NICaN Primary Care Group to work in collaboratively on this piece, based on the templates already available. The works should be available in both electronic and paper versions. 3. Care of the dying & Breaking bad news Dr Gail Johnston has now completed an Audit of the Care of the Dying Pathways within the EHSSB. Gail is also seeking to examine to what extent the Regional Guidelines for Breaking Bad News are being implemented in the EHSSB with a view to identifying the need for further training or organisational structures that would facilitate future uptake. 4. Advances in new Technology Syringe Drivers Dr Wilkinson reported on a presentation made to the guidelines group by Mr Jim Elliot, Principle Engineer, Cardiology & Ann McLean, and Macmillan Palliative Care Nurse RVH. There is increasing concern with regard to how devices meet the recommended safety standards and how to reduce error. New devices have 3 point checking, automatic detection of syringe, automatic flow rates, full range of alarms, battery status and data download to provide an event log. There are now 2 companies in UK who have devices that meet these safety criteria. The current Graseby syringe drivers, which have been on the market and used predominately within Northern Ireland over the past 27 years Most new devices are not compatible with the regionally available monoject syringe, however contractual changes will lead to the withdrawal of the monoject syringes in October 2008. The Guidelines group supports a regional approach to this matter. This was echoed in the Supportive and Palliative care network. An option appraisal, identifying costs, and training issues should be developed through the engagement with Trusts and DHSSPSNI. The issue of Patient safety should be raised with the DHSSPSNI. SPC_0809_09 Evaluation of Supportive and Palliative Care network Deferred to next meeting. . SPC_0809_10 Emerging Issues Mrs Anne Coyle, Bereavement Coordinator, Southern Trust, announced that the Regional Bereavement Strategy is soon to be released. Anne supported the close alignment between the content of the strategy and the work of the regional model and other workstrands within the Supportive and Palliative care network. Ms Eleanor Donaghy, Transplant Coordinator, briefly highlighted the issue of tissue donation. Each year Northern Ireland has a dearth of corneal donations. There is no upper age limit for donation and retrieval is not limited by a cancer diagnosis. Recipients do not require immunosuppressive and the transplant is lifelong. The National Blood Service provided coordination of this donation they may be contacted via 07659180773. It is hoped that Mrs Coyle and Ms Donaghy could provide more comprehensive presentations at a future meeting. Events · Irish Psycho- Oncology Group Seminar, Cork 6 June, Exploring the Struggle for meaning in Cancer · Integrated Care: Putting Research into Practice, 13June, Trinity College, Dublin · Macmillan online conference Friday 13 June 2008, 9am - 5pm · Delivering effective end of life care: developing partnership working 15 Oct 2008, 9.30 -4.15 pm London Network Meeting was closed at 5.00pm SPC_0607_ Dates of Future Meetings (please note the change of venue) 10th September 2008, 1.30 - 5pm venue to be decided15th January 2009, 1.30 - 5pm venue to be decided12th May 2009, 1.30 - 5pm venue to be decided Attendances Apologies Stuart MacDonnellLorna NevinSonja McIlfatrick Donna FitzsimonsKathleen DunnePauline WilkinsonKathy StephensonSheila KellyMarie Nugent,Anne CoyleFiona GilmourJudith HillLorna DicksonMargaret CarlinLoretta GribbenYvonne Duff Lesley NelsonLiz HendersonSue FosterCathy PayneGraeme PaynePatricia MageeGeraldine WeatherupPaula KealyCaroline McAfeeLinda WrayValerie PeacockAnn McCleanRay Elder Martin BradleyHelen HumeGillian RankinHeather MonteverdeJulie DoyleAlison PorterYvonne SmythLiz Atkinson,Glynis HenryMaeve HullyCaroline HughesAnn FinnBob BrownSharon BarrJulie DoyleJanis McCulla .

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Summary: Detailed knowledge on tumor antigen expression and specific immune cells is required for a rational design of immunotherapy for patients with tumor invaded liver. In this study, we confirmed that Cancer/Testis (CT) tumor-associated antigens are frequently expressed in hepatocellular carcinoma (HCC) and searched for the presence of CD8+ T cells specific for these antigens. In 2/10 HLA-A2+ patients with HCC, we found that MAGE-A10 and/or SSX-2 specific CD8+ T cells naturally responded to the disease, since they were enriched in tumor lesions but not in non-tumoral liver. Isolated T cells specifically and strongly killed tumor cells in vitro, suggesting that these CTL were selected in vivo for high avidity antigen recognition, providing the rational for specific immunotherapy of HCC, based on immunization with CT antigens such as MAGE-Al 0 and SSX-2. Type 1 NKT cells express an invariant TCR α chain (Vα24.1α18, paired with Vβ11 in human) and share a specific reactivity to αGalactosylceramide (αGC) presented by CD1d. These cells can display paradoxical immuno-regulatory properties including strong anti-tumor effects upon αGC administration in murine models. To understand why NKT cells were not sufficiently protective against tumor development in patients with tumor invaded liver, we characterized the diversity of Vα24/Vβ11 NKT cells in healthy donors (HD) and cancer patients: NKT cells from HD and patients were generally diverse in terms of TCR β chain (Vβ11) variability and NKT cells from HD showed a variable recognition of αGC loaded CD 1 d multimers. Vα24/ Vβ11 NKT cells can be divided in 3 populations, the CD4, DN (CD4-/CD8-) and CD8 NKT cell subsets that show distinct ability of cytokine production. In addition, our functional analysis revealed that DN and CD8 subsets displayed a higher cytolytic potential and a weaker IFNγ release than the CD4 NKT cell subset. NKT cell subsets were variably represented in the blood of HD and cancer patients. However, HD with high NKT cell frequencies displayed an enrichment of the DN and CD8 subsets, and few of them were suggestive of an oligoclonal expansion in vivo. Comparable NKT cell frequencies were found between blood, non-tumoral liver and tumor of patients. In contrast, we identified a gradual enrichment of CD4 NKT cells from blood to the liver and to the tumor, together with a decrease of DN and CD8 NKT cell subsets. Most patient derived NKT cells were unresponsive upon αGalactosylceramide stimulation ex vivo; NKT cells from few patients displayed a weak responsiveness with different cytokine polarization. The NKT cell repertoire was thus different in tumor tissue, suggesting that CD4 NKT cells infiltrating tumors may be detrimental for protection against tumors and instead may favour the tumor growth/recurrence as recently reported in mice. Résumé en français scientifique : Afin de développer le traitement des patients porteurs d'une tumeur dans le foie par immunothérapie, de nouvelles connaissances sont requises concernant l'expression d'antigènes par les tumeurs et les cellules immunitaires spécifiques de ces antigènes. Nous avons vérifié que des antigènes associés aux tumeurs, tels que les antigènes « Cancer-Testis » (CT), sont fréquemment exprimés par le carcinome hepatocéllulaire (CHC). La recherche de lymphocytes T CD8+ spécifiques (CTL) de ces antigènes a révélé que des CTL spécifiques de MAGE-A10 et/ou SSX-2 ont répondu naturellement à la tumeur chez 2/10 patients étudiés. Ces cellules étaient présentes dans les lésions tumorales mais pas dans le foie adjacent. De plus, ces CTL ont démontré une activité cytolytique forte et spécifique contre les cellules tumorales in vitro, ce qui suggère que ces CTL ont été sélectionnés pour une haute avidité de reconnaissance de l'antigène in vivo. Ces données fournissent une base pour l'immunothérapie spécifique du CHC, en proposant de cibler les antigènes CT tels que MAGE-A10 ou SSX-2. Les cellules NKT de type 1 ont une chaîne α de TCR qui est invariante (chez l'homme, Vα24Jα18, apparié avec Vβ11) et reconnaissent spécifiquement l'αGalactosylceramide (αGC) présenté par CD1d. Ces cellules ont des propriétés immuno¬régulatrices qui peuvent être parfois contradictoires et leur activation par l'αGC induit une forte protection anti-tumorale chez la souris: Afin de comprendre pourquoi ces cellules ne sont pas assez protectrices contre le développement des tumeurs dans le foie chez l'homme, nous avons étudié la diversité des cellules NKT Vα24/Vβ11 d'individus sains (IS) et de patients cancéreux. Les cellules NKT peuvent être sous-divisées en 3 populations : Les CD4, DN (CD4- /CD8-) ou CDS, qui ont la capacité de produire des cytokines différentes. Nos analyses fonctionnelles ont aussi révélé que les sous-populations DN et CD8 ont un potentiel cytolytique plus élevé et une production d'IFNγ plus faible que la sous-population CD4. Ces sous-populations sont représentées de manière variable dans le sang des IS ou des patients. Cependant, les IS avec un taux élevé de cellules NKT ont un enrichissement des sous- populations DN ou CDS, et certains suggèrent qu'il s'agit d'une expansion oligo-clonale in vivo. Les patients avaient des fréquences comparables de cellules NKT entre le sang, le foie et la tumeur. Par contre, la sous-population CD4 était progressivement enrichie du sang vers le foie et la tumeur, tandis que les sous-populations DN ou CD8 était perdues. La plupart des cellules NKT des patients ne réagissaient pas lors de stimulation avec l'αGC ex vivo et les cellules NKT de quelques patients répondaient faiblement et avec des polarisations de cytokines différentes. Ces données suggèrent que les cellules NKT CD4, prédominantes dans les tumeurs, sont inefficaces pour la lutte anti-tumorale et pourraient même favoriser la croissance ou la récurrence tumorale. Donc, une mobilisation spécifique des cellules NKT CD4 négatives par immunothérapie pourrait favoriser l'immunité contre des tumeurs chez l'homme. Résumé en français pour un large public Au sein des globules blancs, les lymphocytes T expriment un récepteur (le TCR), qui est propre à chacun d'entre eux et leur permet d'accrocher de manière très spécifique une molécule appelée antigène. Ce TCR est employé par les lymphocytes pour inspecter les antigènes associés avec des molécules présentatrices à la surface des autres cellules. Les lymphocytes T CD8 reconnaissent un fragment de protéine (ou peptide), qui est présenté par une des molécules du Complexe Majeur d'Histocompatibilité de classe I et tuent la cellule qui présente ce peptide. Ils sont ainsi bien adaptés pour éliminer les cellules qui présentent un peptide issu d'un virus quand la cellule est infectée. D'autres cellules T CD8 reconnaissent des peptides comme les antigènes CT, qui sont produits anormalement par les cellules cancéreuses. Nous avons confirmé que les antigènes CT sont fréquemment exprimés par le cancer du foie. Nous avons également identifié des cellules T CD8 spécifiques d'antigènes CT dans la tumeur, mais pas dans le foie normal de 2 patients sur 10. Cela signifie que ces lymphocytes peuvent être naturellement activés contre la tumeur et sont capables de la trouver. De plus les lymphocytes issus d'un patient ont démontré une forte sensibilité pour reconnaître l'antigène et tuent spécifiquement les cellules tumorales. Les antigènes CT représentent donc des cibles intéressantes qui pourront être intégrés dans des vaccins thérapeutiques du cancer du foie. De cette manière, les cellules T CD8 du patient lui-même pourront être induites à détruire de manière spécifique les cellules cancéreuses. Un nouveau type de lymphocytes T a été récemment découvert: les lymphocytes NKT. Quand ils reconnaissent un glycolipide présenté par la molécule CD1d, ils sont capables, de manière encore incomprise, d'initier, d'augmenter, ou à l'inverse d'inhiber la défense immunitaire. Ces cellules NKT ont démontré qu'elles jouent un rôle important dans la défense contre les tumeurs et particulièrement dans le foie des souris. Nous avons étudié les cellules NKT de patients atteints d'une tumeur dans le foie, afin de comprendre pourquoi elles ne sont pas assez protectrice chez l'homme. Les lymphocytes NKT peuvent être sous-divisés en 3 populations: Les CD4, les DN (CD4-/CD8-) et les CD8. Ces 3 classes de NKT peuvent produire différents signaux chimiques appelés cytokines. Contrairement aux cellules NKT DN ou CDS, seules les cellules NKT CD4 sont capables de produire des cytokines qui sont défavorables pour la défense anti-tumorale. Par ailleurs nous avons trouvé que les cellules NKT CD4 tuent moins bien les cellules cancéreuses que les cellules NKT DN ou CD8. L'analyse des cellules NKT, fraîchement extraites du sang, du foie et de la tumeur de patients a révélé que les cellules NKT CD4 sont progressivement enrichies du sang vers le foie et la tumeur. La large prédominance des NKT CD4 à l'intérieur des tumeurs suggère que, chez l'homme, ces cellules sont inappropriées pour la lutte anti-tumorale. Par ailleurs, la plupart des cellules NKT de patients n'étaient pas capables de produire des cytokines après stimulation avec un antigène. Cela explique également pourquoi ces cellules ne protègent pas contre les tumeurs dans le foie.

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The treatment of some cancer patients has shifted from traditional, non-specific cytotoxic chemotherapy to chronic treatment with molecular targeted therapies. Imatinib mesylate, a selective inhibitor of tyrosine kinases (TKIs) is the most prominent example of this new era and has opened the way to the development of several additional TKIs, including sunitinib, nilotinib, dasatinib, sorafenib and lapatinib, in the treatment of various hematological malignancies and solid tumors. All these agents are characterized by an important inter-individual pharmacokinetic variability, are at risk for drug interactions, and are not devoid of toxicity. Additionally, they are administered for prolonged periods, anticipating the careful monitoring of their plasma exposure via Therapeutic Drug Monitoring (TDM) to be an important component of patients' follow-up. We have developed a liquid chromatography-tandem mass spectrometry method (LC-MS/MS) requiring 100 microL of plasma for the simultaneous determination of the six major TKIs currently in use. Plasma is purified by protein precipitation and the supernatant is diluted in ammonium formate 20 mM (pH 4.0) 1:2. Reverse-phase chromatographic separation of TKIs is obtained using a gradient elution of 20 mM ammonium formate pH 2.2 and acetonitrile containing 1% formic acid, followed by rinsing and re-equilibration to the initial solvent composition up to 20 min. Analyte quantification, using matrix-matched calibration samples, is performed by electro-spray ionization-triple quadrupole mass spectrometry by selected reaction monitoring detection using the positive mode. The method was validated according to FDA recommendations, including assessment of extraction yield, matrix effects variability (<9.6%), overall process efficiency (87.1-104.2%), as well as TKIs short- and long-term stability in plasma. The method is precise (inter-day CV%: 1.3-9.4%), accurate (-9.2 to +9.9%) and sensitive (lower limits of quantification comprised between 1 and 10 ng/mL). This is the first broad-range LC-MS/MS assay covering the major currently in-use TKIs. It is an improvement over previous methods in terms of convenience (a single extraction procedure for six major TKIs, reducing significantly the analytical time), sensitivity, selectivity and throughput. It may contribute to filling the current knowledge gaps in the pharmacokinetics/pharmacodynamics relationships of the latest TKIs developed after imatinib and better define their therapeutic ranges in different patient populations in order to evaluate whether a systematic TDM-guided dose adjustment of these anticancer drugs could contribute to minimize the risk of major adverse reactions and to increase the probability of efficient, long lasting, therapeutic response.

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Background: The imatinib trough plasma concentration (C(min)) correlates with clinical response in cancer patients. Therapeutic drug monitoring (TDM) of plasma C(min) is therefore suggested. In practice, however, blood sampling for TDM is often not performed at trough. The corresponding measurement is thus only remotely informative about C(min) exposure. Objectives: The objectives of this study were to improve the interpretation of randomly measured concentrations by using a Bayesian approach for the prediction of C(min), incorporating correlation between pharmacokinetic parameters, and to compare the predictive performance of this method with alternative approaches, by comparing predictions with actual measured trough levels, and with predictions obtained by a reference method, respectively. Methods: A Bayesian maximum a posteriori (MAP) estimation method accounting for correlation (MAP-ρ) between pharmacokinetic parameters was developed on the basis of a population pharmacokinetic model, which was validated on external data. Thirty-one paired random and trough levels, observed in gastrointestinal stromal tumour patients, were then used for the evaluation of the Bayesian MAP-ρ method: individual C(min) predictions, derived from single random observations, were compared with actual measured trough levels for assessment of predictive performance (accuracy and precision). The method was also compared with alternative approaches: classical Bayesian MAP estimation assuming uncorrelated pharmacokinetic parameters, linear extrapolation along the typical elimination constant of imatinib, and non-linear mixed-effects modelling (NONMEM) first-order conditional estimation (FOCE) with interaction. Predictions of all methods were finally compared with 'best-possible' predictions obtained by a reference method (NONMEM FOCE, using both random and trough observations for individual C(min) prediction). Results: The developed Bayesian MAP-ρ method accounting for correlation between pharmacokinetic parameters allowed non-biased prediction of imatinib C(min) with a precision of ±30.7%. This predictive performance was similar for the alternative methods that were applied. The range of relative prediction errors was, however, smallest for the Bayesian MAP-ρ method and largest for the linear extrapolation method. When compared with the reference method, predictive performance was comparable for all methods. The time interval between random and trough sampling did not influence the precision of Bayesian MAP-ρ predictions. Conclusion: Clinical interpretation of randomly measured imatinib plasma concentrations can be assisted by Bayesian TDM. Classical Bayesian MAP estimation can be applied even without consideration of the correlation between pharmacokinetic parameters. Individual C(min) predictions are expected to vary less through Bayesian TDM than linear extrapolation. Bayesian TDM could be developed in the future for other targeted anticancer drugs and for the prediction of other pharmacokinetic parameters that have been correlated with clinical outcomes.

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Biomarker analysis is playing an essential role in cancer diagnosis, prognosis, and prediction. Quantitative assessment of immunohistochemical biomarker expression on tumor tissues is of clinical relevance when deciding targeted treatments for cancer patients. Here, we report a microfluidic tissue processor that permits accurate quantification of the expression of biomarkers on tissue sections, enabled by the ultra-rapid and uniform fluidic exchange of the device. An important clinical biomarker for invasive breast cancer is human epidermal growth factor receptor 2 [(HER2), also known as neu], a transmembrane tyrosine kinase that connotes adverse prognostic information for the patients concerned and serves as a target for personalized treatment using the humanized antibody trastuzumab. Unfortunately, when using state-of-the-art methods, the intensity of an immunohistochemical signal is not proportional to the extent of biomarker expression, causing ambiguous outcomes. Using our device, we performed tests on 76 invasive breast carcinoma cases expressing various levels of HER2. We eliminated more than 90% of the ambiguous results (n = 27), correctly assigning cases to the amplification status as assessed by in situ hybridization controls, whereas the concordance for HER2-negative (n = 31) and -positive (n = 18) cases was 100%. Our results demonstrate the clinical potential of microfluidics for accurate biomarker expression analysis. We anticipate our technique will be a diagnostic tool that will provide better and more reliable data, onto which future treatment regimes can be based.

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PURPOSE: Ipilimumab is a monoclonal antibody that blocks the immune-inhibitory interaction between CTL antigen 4 (CTLA-4) and its ligands on T cells. Clinical trials in cancer patients with ipilimumab have shown promising antitumor activity, particularly in patients with advanced melanoma. Often, tumor regressions in these patients are correlated with immune-related side effects such as dermatitis, enterocolitis, and hypophysitis. Although these reactions are believed to be immune-mediated, the antigenic targets for the cellular or humoral immune response are not known. EXPERIMENTAL DESIGN: We enrolled patients with advanced melanoma in a phase II study with ipilimumab. One of these patients experienced a complete remission of his tumor. The specificity and functional properties of CD8-positive T cells in his peripheral blood, in regressing tumor tissue, and at the site of an immune-mediated skin rash were investigated. RESULTS: Regressing tumor tissue was infiltrated with CD8-positive T cells, a high proportion of which were specific for Melan-A. The skin rash was similarly infiltrated with Melan-A-specific CD8-positive T cells, and a dramatic (>30-fold) increase in Melan-A-specific CD8-positive T cells was apparent in peripheral blood. These cells had an effector phenotype and lysed Melan-A-expressing tumor cells. CONCLUSIONS: Our results show that Melan-A may be a major target for both the autoimmune and antitumor reactions in patients treated with anti-CTLA-4, and describe for the first time the antigen specificity of CD8-positive T cells that mediate tumor rejection in a patient undergoing treatment with an anti-CTLA-4 antibody. These findings may allow a better integration of ipilimumab into other forms of immunotherapy.

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Although tumor-specific CD8 T-cell responses often develop in cancer patients, they rarely result in tumor eradication. We aimed at studying directly the functional efficacy of tumor-specific CD8 T cells at the site of immune attack. Tumor lesions in lymphoid and nonlymphoid tissues (metastatic lymph nodes and soft tissue/visceral metastases, respectively) were collected from stage III/IV melanoma patients and investigated for the presence and function of CD8 T cells specific for the tumor differentiation antigen Melan-A/MART-1. Comparative analysis was conducted with peripheral blood T cells. We provide evidence that in vivo-priming selects, within the available naive Melan-A/MART-1-specific CD8 T-cell repertoire, cells with high T-cell receptor avidity that can efficiently kill melanoma cells in vitro. In vivo, primed Melan-A/MART-1-specific CD8 T cells accumulate at high frequency in both lymphoid and nonlymphoid tumor lesions. Unexpectedly, however, whereas primed Melan-A/MART-1-specific CD8 T cells that circulate in the blood display robust inflammatory and cytotoxic functions, those that reside in tumor lesions (particularly in metastatic lymph nodes) are functionally tolerant. We show that both the lymph node and the tumor environments blunt T-cell effector functions and offer a rationale for the failure of tumor-specific responses to effectively counter tumor progression.

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Despite the presence of tumor-specific effector cells in the circulation of cancer patients, the immune response of the majority of these patients is not sufficient to prevent the growth and spread of their tumors. That tumor cells can be killed in vitro by tumor-reactive cytotoxic T cells is testimony to the fact that the tumors are not inherently resistant to T cell killing, but rather that there is a failure in immune recognition and effector cell activation. Many reasons for this failure of the body's defense system have been suggested, including the inability of tumor-reactive lymphocytes to migrate to tumor tissue. Here we designed a strategy to improve homing of primary lymphocytes into vascularized tumors. As a homing molecule we selected the integrin alpha v beta 3 since it is expressed by angiogenic vascular endothelium in tumors. To promote lymphocyte adhesion to alpha v beta 3 we "painted" primary lymphocytes with a recombinant, glycosylphosphatidylinositol-linked high-affinity ligand for alpha v beta 3. These painted lymphocytes specifically bound to alpha v beta 3 in vitro and homed to vascularized, solid tumors in vivo. This novel strategy may provide a significant advance in anti-tumor treatment such as adoptive immune therapy.

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Introduction. Preoperative malnutrition is a major risk factor for increased postoperative morbidity and mortality. Definition and diagnosis of malnutrition and its treatment is still subject for controversy. Furthermore, practical implementation of nutrition-related guidelines is unknown. Methods. A review of the available literature and of current guidelines on perioperative nutrition was conducted. We focused on nutritional screening and perioperative nutrition in patients undergoing digestive surgery, and we assessed translation of recent guidelines in clinical practice. Results and Conclusions. Malnutrition is a well-recognized risk factor for poor postoperative outcome. The prevalence of malnutrition depends largely on its definition; about 40% of patients undergoing major surgery fulfil current diagnostic criteria of being at nutritional risk. The Nutritional Risk Score is a pragmatic and validated tool to identify patients who should benefit from nutritional support. Adequate nutritional intervention entails reduced (infectious) complications, hospital stay, and costs. Preoperative oral supplementation of a minimum of five days is preferable; depending on the patient and the type of surgery, immune-enhancing formulas are recommended. However, surgeons' compliance with evidence-based guidelines remains poor and efforts are necessary to implement routine nutritional screening and nutritional support.

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Late treatment of invasive candidiasis (IC) results in severe complications and high mortality. New tools are needed for early diagnosis. We conducted a retrospective study to assess the diagnostic utility of mannan antigenemia (Mn) and antimannan antibodies (anti-Mn) in neutropenic cancer patients at high risk for candidiasis. Twenty-eight patients with IC (based on European Organization for Research and Treatment of Cancer and Mycoses Study Group definitions) and 25 controls were studied. Mn and anti-Mn were positive (> or = 0.25 ng/mL and > or = 5 AU/mL, respectively) in 25/28 (89%) patients with candidiasis and in 4/25 (16%) controls: sensitivity, 89%; specificity, 84%; positive predictive value, 86%; negative predictive value, 88%. In patients with hepatosplenic lesions, assessing Mn/anti-Mn shortened the median time of diagnosis of candidiasis when compared with imaging (9 versus 25 days after fever onset as first sign of infection; P < 0.001). Candidiasis was diagnosed before neutrophil recovery in 78% and 11% of cases with Mn/anti-Mn and radiology, respectively (P < 0.001). Mn and anti-Mn may be useful for early noninvasive diagnosis of IC.

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Objective. Mandibular osteoradionecrosis (ORN) is a serious complication of radiotherapy (RT) in head and neck cancer patients. The aim of this study was to analyze the incidence of and risk factors for mandibular ORN in squamous cell carcinoma (SCC) of the oral cavity and oropharynx.Study Design. Case series with chart review.Setting. University tertiary care center for head and neck oncology.Subjects and Methods. Seventy-three patients treated for stage I to IV SCC of the oral cavity and oropharynx between 2000 and 2007, with a minimum follow-up of 2 years, were included in the study. Treatment modalities included both RT with curative intent and adjuvant RT following tumor surgery. The log-rank test and Cox model were used for univariate and multivariate analyses.Results. The incidence of mandibular ORN was 40% at 5 years. Using univariate analysis, the following risk factors were identified: oral cavity tumors (P < .01), bone invasion (P < .02), any surgery prior to RT (P < .04), and bone surgery (P < .0001). By multivariate analysis, mandibular surgery proved to be the most important risk factor and the only one reaching statistical significance (P < .0002).Conclusion. Mandibular ORN is a frequent long-term complication of RT for oral cavity and oropharynx cancers. Mandibular surgery before irradiation is the only independent risk factor. These aspects must be considered when planning treatment for these tumors.

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BACKGROUND On its physiological cellular context, PTTG1 controls sister chromatid segregation during mitosis. Within its crosstalk to the cellular arrest machinery, relies a checkpoint of integrity for which gained the over name of securin. PTTG1 was found to promote malignant transformation in 3T3 fibroblasts, and further found to be overexpressed in different tumor types. More recently, PTTG1 has been also related to different processes such as DNA repair and found to trans-activate different cellular pathways involving c-myc, bax or p53, among others. PTTG1 over-expression has been correlated to a worse prognosis in thyroid, lung, colorectal cancer patients, and it can not be excluded that this effect may also occur in other tumor types. Despite the clinical relevance and the increasing molecular characterization of PTTG1, the reason for its up-regulation remains unclear. METHOD We analysed PTTG1 differential expression in PC-3, DU-145 and LNCaP tumor cell lines, cultured in the presence of the methyl-transferase inhibitor 5-Aza-2'-deoxycytidine. We also tested whether the CpG island mapping PTTG1 proximal promoter evidenced a differential methylation pattern in differentiated thyroid cancer biopsies concordant to their PTTG1 immunohistochemistry status. Finally, we performed whole-genome LOH studies using Affymetix 50 K microarray technology and FRET analysis to search for allelic imbalances comprising the PTTG1 locus. CONCLUSION Our data suggest that neither methylation alterations nor LOH are involved in PTTG1 over-expression. These data, together with those previously reported, point towards a post-transcriptional level of misregulation associated to PTTG1 over-expression.