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1.
Artif Intell Med ; 133: 102407, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36328667

RESUMO

Recently, Artificial Intelligence namely Deep Learning methods have revolutionized a wide range of domains and applications. Besides, Digital Pathology has so far played a major role in the diagnosis and the prognosis of tumors. However, the characteristics of the Whole Slide Images namely the gigapixel size, high resolution and the shortage of richly labeled samples have hindered the efficiency of classical Machine Learning methods. That goes without saying that traditional methods are poor in generalization to different tasks and data contents. Regarding the success of Deep learning when dealing with Large Scale applications, we have resorted to the use of such models for histopathological image segmentation tasks. First, we review and compare the classical UNet and Att-UNet models for colon cancer WSI segmentation in a sparsely annotated data scenario. Then, we introduce novel enhanced models of the Att-UNet where different schemes are proposed for the skip connections and spatial attention gates positions in the network. In fact, spatial attention gates assist the training process and enable the model to avoid irrelevant feature learning. Alternating the presence of such modules namely in our Alter-AttUNet model adds robustness and ensures better image segmentation results. In order to cope with the lack of richly annotated data in our AiCOLO colon cancer dataset, we suggest the use of a multi-step training strategy that also deals with the WSI sparse annotations and unbalanced class issues. All proposed methods outperform state-of-the-art approaches but Alter-AttUNet generates the best compromise between accurate results and light network. The model achieves 95.88% accuracy with our sparse AiCOLO colon cancer datasets. Finally, to evaluate and validate our proposed architectures we resort to publicly available WSI data: the NCT-CRC-HE-100K, the CRC-5000 and the Warwick colon cancer histopathological dataset. Respective accuracies of 99.65%, 99.73% and 79.03% were reached. A comparison with state-of-art approaches is established to view and compare the key solutions for histopathological image segmentation.


Assuntos
Neoplasias do Colo , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Inteligência Artificial , Aprendizado de Máquina Supervisionado , Neoplasias do Colo/diagnóstico por imagem , Atenção
2.
Ann Oncol ; 33(6): 628-637, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35306156

RESUMO

BACKGROUND: Histological characteristics at the invasive front may reflect tumor aggressiveness; specifically, tumor budding (Bd) is an emerging prognostic biomarker in colon cancer (CC). We explored further the significance of Bd for risk stratification by evaluating survival of stage III CC patients included in the IDEA-France phase III trial. PATIENTS AND METHODS: This post-hoc study was conducted on tissue slides from 1048 stage III CC patients. Bd was scored by central review by the Bd criteria of the 2016 International Tumor Budding Consensus Conference (ITBCC 2016) and classified as Bd1 (0-4 buds/0.785 mm2), Bd2 (5-9 buds), and Bd3 (≥10 buds) categories. Disease-free survival (DFS) and overall survival (OS) were analyzed by the log-rank test. Clinicopathological features and Immunoscore® were correlated with Bd. RESULTS: Overall, Bd1, Bd2, and Bd3 were observed in 39%, 28%, and 33% of CC, respectively. Bd2 and Bd3 were associated with vascular (P = 0.002) and perineural invasions (P = 0.0009). The 3-year DFS and the 5-year OS rates for Bd (1 versus 2-3) were 79.4% versus 67.2% (P = 0.001) and 89.2% versus 80.8% (P = 0.001), respectively. This was confirmed after adjustment for relevant clinicopathological features for DFS [hazard ratio (HR) 1.41, 95% confidence interval (CI) 1.12-1.77, P = 0.003] and OS (HR 1.65, 95% CI 1.22-2.22, P = 0.001). When combined with pTN stage and Immunoscore® subgroups, Bd significantly improved disease prognostication. CONCLUSIONS: Bd demonstrated its independent prognostic value for DFS and OS. Given these findings, Bd as per the ITBCC 2016 should be mandatory in every pathology report in stage III CC patients. Bd and Immunoscore® could play a complementary role in personalized health care in this setting.


Assuntos
Neoplasias do Colo , Neoplasias do Colo/patologia , Intervalo Livre de Doença , França/epidemiologia , Humanos , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais
3.
Comput Biol Med ; 136: 104730, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34375901

RESUMO

Nowadays, digital pathology plays a major role in the diagnosis and prognosis of tumours. Unfortunately, existing methods remain limited when faced with the high resolution and size of Whole Slide Images (WSIs) coupled with the lack of richly annotated datasets. Regarding the ability of the Deep Learning (DL) methods to cope with the large scale applications, such models seem like an appealing solution for tissue classification and segmentation in histopathological images. This paper focuses on the use of DL architectures to classify and highlight colon cancer regions in a sparsely annotated histopathological data context. First, we review and compare state-of-the-art Convolutional Neural networks (CNN) including the AlexNet, vgg, ResNet, DenseNet and Inception models. To cope with the shortage of rich WSI datasets, we have resorted to the use of transfer learning techniques. This strategy comes with the hallmark of relying on a large size computer vision dataset (ImageNet) to train the network and generate a rich collection of learnt features. The testing and evaluation of such models on our AiCOLO colon cancer dataset ensure accurate patch-level classification results reaching up to 96.98% accuracy rate with ResNet. The CNN models have also been tested and evaluated with the CRC-5000, nct-crc-he-100k and merged datasets. ResNet respectively achieves 96.77%, 99.76% and 99.98% for the three publicly available datasets. Then, we present a pixel-wise segmentation strategy for colon cancer WSIs through the use of both UNet and SegNet models. We introduce a multi-step training strategy as a remedy for the sparse annotation of histopathological images. UNet and SegNet are used and tested in different training scenarios including data augmentation and transfer learning and ensure up to 76.18% and 81.22% accuracy rates. Besides, we test our training strategy and models on the CRC-5000, nct-crc-he-100k and Warwick datasets. Respective accuracy rates of 98.66%, 99.12% and 78.39% were achieved by SegNet. Finally, we analyze the existing models to discover the most suitable network and the most effective training strategy for our colon tumour segmentation case study.1.


Assuntos
Neoplasias do Colo , Aprendizado Profundo , Neoplasias do Colo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação
4.
Eur J Med Genet ; 64(5): 104196, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33753322

RESUMO

With next generation sequencing, physicians are faced with more complex and uncertain data, particularly incidental findings (IF). Guidelines for the return of IF have been published by learned societies. However, little is known about how patients are affected by these results in a context of oncogenetic testing. Over 4 years, 2500 patients with an indication for genetic testing underwent a gene cancer panel. If an IF was detected, patients were contacted by a physician/genetic counsellor and invited to take part in a semi-structured interview to assess their understanding of the result, the change in medical care, the psychological impact, and the transmission of results to the family. Fourteen patients (0.56%) were delivered an IF in a cancer predisposition gene (RAD51C, PMS2, SDHC, RET, BRCA2, CHEK2, CDKN2A, CDH1, SUFU). Two patients did not collect the results and another two died before the return of results. Within the 10 patients recontacted, most of them reported surprise at the delivery of IF, but not anxiety. The majority felt they had chosen to obtain the result and enough information to understand it. They all initiated the recommended follow-up and did not regret the procedure. Information regarding the IF was transmitted to their offspring but siblings or second-degree relatives were not consistently informed. No major adverse psychological events were found in our experience. IF will be inherent to the development of sequencing, even for restricted gene panels, so it is important to increase our knowledge on the impact of such results in different contexts.


Assuntos
Atitude , Predisposição Genética para Doença/psicologia , Neoplasias/genética , Pacientes/psicologia , Adulto , Idoso , Feminino , Testes Genéticos , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia
5.
Clin Transl Radiat Oncol ; 24: 116-122, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32793819

RESUMO

INTRODUCTION: Modern accelerators have the "flattening filter-free" (FFF) technique to deliver RT with a moderate high-dose rate, currently used in limited clinical indications. No scientifically established data are currently available on the possible effects of this high dose rate on the anti-tumor immune response. We therefore propose here to study these effects in a preclinical CT26 murine colorectal tumor model. MATERIAL AND METHODS: In-vitro, CT26 cells were irradiated on a Varian TrueBeam® linac at 3 different dose rates (4; 12 or 24 Gy/min) using the FFF mode. Activation of the anti-tumor immune response was evaluated by the analysis of induction of genes of the type I interferon pathway by RT-qPCR, and by the study of the induction of immunogenic death biomarkers. In-vivo, an efficacy study of RT delivering 16.5 Gy at 2 different dose rates was performed in immunocompetent Balb/c mice carrying CT26 syngeneic tumors, as well as an immunomonitoring analysed by flow cytometry and a transcriptomic analysis using RNA sequencing. Statistical analyzes were performed using non-parametric tests. RESULTS: In-vitro, no significant influence of an increase in FFF dose rate was shown for the induction of genes of the type I interferon pathway as well as for the studied immunogenic death markers (HMGB1 secretion). In-vivo, no difference in terms of tumor growth retardation between the 2 dose rates used was demonstrated, as well as for the composition of immune cell infiltrates within tumor microenvironment and the expression of immune checkpoints in immunomonitoring and RNAseq. CONCLUSION: In this study involving the CT26 model, no influence of a moderate high dose rate in FFF technique on the anti-tumor immune response was demonstrated, which would make studies of associations between RT and checkpoint inhibitors fit with this technique of RT. However, further explorations using other cellular models seem to be of interest.

6.
Support Care Cancer ; 28(1): 287-293, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31044304

RESUMO

PURPOSE: Our objective was to compare patient's expectations to their experience and to identify factors predictive of patient's perception of long-term LMWH for the treatment of cancer-associated thrombosis (CAT). METHODS: Results from the validated Perception Anticoagulant Treatment Questionnaires (PACTQ) completed before inclusion (PACTQ1 for expectations) and at the end (PACTQ2 for convenience and satisfaction) of the 6-month TROPIQUE study were studied with principal component analysis. Possible predictive factors of improved perception of LMWH treatment were analyzed with the Kruskall-Wallis test. RESULTS: Among 409 included patients treated with LMWH, 269 PACT-Q1 and 139 PACT-Q2 were evaluable for treatment perception. Patients had high expectations (A1-A7 score of 26.7 ± 3.5, max = 35). Treatment cost (A7 = 1.90 ± 1.31) and concern about a mistake in anticoagulation (A5 = 1.93 ± 1.12) had little importance while LMWH treatment was considered easy to use (A4 = 4.20 ± 0.93). Six-month treatment with LMWH was associated with a high rate of convenience (B1-B11, C1-C2 = 55.1 ± 8.38, max = 65) and a high satisfaction score (D1-D7 = 25.1 ± 4.32, max = 35). Patients' confidence in treatment and perception of possible LMWH side effects were moderate while perception of autonomy and independence significantly improved at the end of the study compared to inclusion. PACT-Q2 satisfaction score was low in patients who experienced bleeding (PACT-Q2 24.1 ± 3.3 vs. 25.1 ± 4.3). LMWH twice daily tended to be found less convenient compared than once daily (53.3 ± 7.2 vs. 55.0 ± 8.3). CONCLUSION: CAT patients had a good perception of the 6-month LMWH treatment when comparing expectations and experience. Using a quantitative scale validated in the general population for VTE and subcutaneous injection and including a large number of patients, bleeding complications and LMWH twice daily were associated with a nonsignificant trend towards a worsen perception.


Assuntos
Heparina de Baixo Peso Molecular/uso terapêutico , Neoplasias/complicações , Satisfação do Paciente , Percepção/fisiologia , Trombose/tratamento farmacológico , Trombose/etiologia , Adulto , Anticoagulantes/uso terapêutico , Feminino , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Hemorragia/psicologia , Humanos , Injeções Subcutâneas/psicologia , Assistência de Longa Duração/psicologia , Assistência de Longa Duração/estatística & dados numéricos , Masculino , Adesão à Medicação/psicologia , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Neoplasias/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários , Trombose/epidemiologia , Trombose/psicologia , Fatores de Tempo , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia
7.
Opt Express ; 27(4): 4386-4403, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876058

RESUMO

Transverse mode competition and instabilities in high-power fiber oscillators have been studied experimentally by monitoring the dynamic power exchanges and characteristic frequencies of the transmitted fundamental mode (FM) and scattered high-order modes (HOMs) of the fiber laser cavity under CW and pulsed pumping. The FM and HOM power evolution indicates the presence of two competing effective laser cavities which result in rich output dynamics and full chaotic operation. The thermal and inversion related contributions to the observed instabilities have been identified by monitoring the associated characteristic instability frequencies under pulsed pumping. It is shown that in the transient regime, both inversion and thermal effects contribute successively to the observed power instabilities. Increasing the pump power leads to full chaotic response through an interplay between transverse and longitudinal mode instabilities.

8.
Ann Oncol ; 30(6): 934-944, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30924846

RESUMO

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) represent a prognostic factor for survival in primary breast cancer (BC). Nonetheless, neoepitope load and TILs cytolytic activity are modest in BC, compromising the efficacy of immune-activating antibodies, which do not yet compete against immunogenic chemotherapy. PATIENTS AND METHODS: We analyzed by functional flow cytometry the immune dynamics of primary and metastatic axillary nodes [metastatic lymph nodes (mLN)] in early BC (EBC) after exposure to T-cell bispecific antibodies (TCB) bridging CD3ε and human epidermal growth factor receptor 2 (HER2) or Carcinoembryonic Antigen-Related Cell Adhesion Molecule 5 (CEACAM5), before and after chemotherapy. Human leukocyte antigen (HLA) class I loss was assessed by whole exome sequencing and immunohistochemistry. One hundred primary BC, 64 surrounding 'healthy tissue' and 24 mLN-related parameters were analyzed. RESULTS: HLA loss of heterozygosity was observed in EBC, at a clonal and subclonal level and was associated with regulatory T cells and T-cell immunoglobulin and mucin-domain-3 expression restraining the immuno-stimulatory effects of neoadjuvant chemotherapy. TCB bridging CD3ε and HER2 or CEACAM5 could bypass major histocompatibility complex (MHC) class I loss, partially rescuing T-cell functions in mLN. CONCLUSION: TCB should be developed in BC to circumvent low MHC/peptide complexes.


Assuntos
Anticorpos Biespecíficos/administração & dosagem , Anticorpos Biespecíficos/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/imunologia , Neoplasias da Mama/terapia , Antígenos de Histocompatibilidade Classe I/genética , Linfócitos do Interstício Tumoral/imunologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Seguimentos , Variação Genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Linfonodos/imunologia , Linfonodos/patologia , Metástase Linfática , Terapia Neoadjuvante , Invasividade Neoplásica , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo
9.
Eur J Cancer ; 111: 12-20, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30798084

RESUMO

PURPOSE: The role of chemotherapy has not been established in the treatment of metastatic squamous cell oesophageal cancer (mESCC). PATIENTS AND METHODS: E-DIS is a discontinuation trial, aimed at estimating efficacy, quality of life and safety of chemotherapy continuation (CT-CONT) in patients with mESCC who are free from progression after a selection phase of chemotherapy. The primary end-point was overall survival. RESULTS: Sixty-seven patients were randomised. The 9-month survival rate was 50% (85% confidence interval [CI]: 37-62%) and 48% (85% CI: 35-60%) in the CT-CONT arm and in the chemotherapy discontinuation (CT-DISC) arm, respectively. The time until definitive deterioration of the global health status (European Organisation for Research and Treatment of Cancer [EORTC] core quality of life questionnaire) was 6.6 months (95% CI: 3.3-12.4) for the CT-CONT arm and 4.2 months (95% CI: 2.9-6.3) for the CT-DISC arm, with a hazard ratio (HRCT-DISC/CT-CONT) = 1.44 (95% CI: 0.82-2.53). We observed a beneficial trend in favour of CT-CONT (HR > 1) for most dimensions, including an improvement for three dimensions (dysphagia, eating and oesophageal pain) of the EORTC Oesophageal Cancer Module QLQ-OES18. CONCLUSION: CT-CONT provides an overall survival rate that is similar to CT-DISC. E-DIS trial provides valuable data to support shared decision-making between physicians and patients regarding CT-CONT/DISC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Resultado do Tratamento
10.
Eur J Med Genet ; 62(6): 103529, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30165243

RESUMO

With the development of next generation sequencing, beyond identifying the cause of manifestations that justified prescription of the test, other information with potential interest for patients and their families, defined as secondary findings (SF), can be provided once patients have given informed consent, in particular when therapeutic and preventive options are available. The disclosure of such findings has caused much debate. The aim of this work was to summarize all opinion-based studies focusing on SF, so as to shed light on the concerns that this question generate. A review of the literature was performed, focusing on all PubMed articles reporting qualitative, quantitative or mixed studies that interviewed healthcare providers, participants, or society regarding this subject. The methodology was carefully analysed, in particular whether or not studies made the distinction between actionable and non-actionable SF, in a clinical or research context. From 2010 to 2016, 39 articles were compiled. A total of 14,868 people were interviewed (1259 participants, 6104 healthcare providers, 7505 representatives of society). When actionable and non-actionable SF were distinguished (20 articles), 92% of respondents were keen to have results regarding actionable SF (participants: 88%, healthcare providers: 86%, society: 97%), against 70% (participants: 83%, healthcare providers: 62%, society: 73%) for non-actionable SF. These percentages were slightly lower in the specific situation of children probands. For respondents, the notion of the «patient's choice¼ is crucial. For healthcare providers, the importance of defining policies for SF among diagnostic lab, learning societies and/or countries is outlined, in particular regarding the content and extension of the list of actionable genes to propose, the modalities of information, and the access to information about adult-onset diseases in minors. However, the existing literature should be taken with caution, since most articles lack a clear definition of SF and actionability, and referred to hypothetical scenarios with limited information to respondents. Studies conducted by multidisciplinary teams involving patients with access to results are sadly lacking, in particular in the medium term after the results have been given. Such studies would feed the debate and make it possible to measure the impact of such findings and their benefit-risk ratio.


Assuntos
Comportamento de Escolha , Sequenciamento do Exoma/ética , Aconselhamento Genético/psicologia , Testes Genéticos/ética , Achados Incidentais , Participação dos Interessados , Atitude , Revelação , Aconselhamento Genético/normas , Humanos , Pacientes/psicologia
12.
Oncoimmunology ; 7(3): e1396402, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29399395

RESUMO

Introduction: Some studies have suggested that baseline tumor-infiltrating-lymphocytes (TILs), such as CD8+ and FoxP3+ T-cells, may be associated with a better prognosis in colorectal cancer. We sought to investigate modulation of the immune response by preoperative radiotherapy (preopRT) and its impact on survival in locally advanced rectal cancer (LARC). Materials & Methods: We analyzed data for 237 patients with LARC who received RT. Density of TILS (CD8+ and FoxP3+) in intraepithelial (iTILs) and stromal compartments (sTILs) were evaluated from surgery pathological specimens and biopsies performed at baseline. The primary endpoint was to assess the impact of infiltration of the tumor or tumor site after preopRT on progression-free survival (PFS) and overall survival (OS). Secondary endpoints were the impact of dose fractionation scheme on TILs. Results: In univariate analysis, several factors significantly correlated (p<0.05) with PFS and/or OS (T-stage, M-stage, the delay between RT and surgery). A high level of post-treatment FoxP3+ TIL density correlated significantly with a better PFS (p = 0.007). In multivariate analysis, a decrease in the CD8+/FoxP3+ iTILs ratio after preopRT correlated with better PFS and OS (p = 0.049 and p = 0.024, respectively). More particularly, patients with a delta CD8+/FoxP3+ <-3.8 had better PFS and OS. Interestingly, the dose fractionation scheme significantly influenced the CD8+/FoxP3+ ratio after treatment (p = 0.027) with a lower ratio with hypofractionated RT (≥2 Gy). Conclusion: Patients with LARC who had a significant decrease in the CD8+/FoxP3+ ratio after preopRT were more likely to live longer. This ratio needs to be validated prospectively to guide physicians in adjuvant treatment decision-making.

13.
Oncogene ; 35(35): 4611-22, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-26853468

RESUMO

The omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) has anti-inflammatory and anti-cancer properties. Among pro-inflammatory mediators, tumor necrosis factor α (TNFα) plays a paradoxical role in cancer biology with induction of cancer cell death or survival depending on the cellular context. The objective of the study was to evaluate the role of TNFα in DHA-mediated tumor growth inhibition and colon cancer cell death. The treatment of human colorectal cancer cells, HCT-116 and HCT-8 cells, with DHA triggered apoptosis in autocrine TNFα-dependent manner. We demonstrated that DHA-induced increased content of TNFα mRNA occurred through a post-transcriptional regulation via the down-regulation of microRNA-21 (miR-21) expression. Treatment with DHA led to nuclear accumulation of Foxo3a that bounds to the miR-21 promoter triggering its transcriptional repression. Moreover, inhibition of RIP1 kinase and AMP-activated protein kinase α reduced Foxo3a nuclear-cytoplasmic shuttling and subsequent increase of TNFα expression through a decrease of miR-21 expression in DHA-treated colon cancer cells. Finally, we were able to show in HCT-116 xenograft tumor-bearing nude mice that a DHA-enriched diet induced a decrease of human miR-21 expression and an increase of human TNFα mRNA expression limiting tumor growth in a cancer cell-derived TNFα dependent manner. Altogether, the present work highlights a novel mechanism for anti-cancer action of DHA involving colon cancer cell death mediated through autocrine action of TNFα.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/administração & dosagem , MicroRNAs/biossíntese , Fator de Necrose Tumoral alfa/biossíntese , Animais , Apoptose/efeitos dos fármacos , Comunicação Autócrina , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Proteína Forkhead Box O3/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Ann Oncol ; 26(9): 1813-1823, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25922066

RESUMO

Recent clinical trials revealed the impressive efficacy of immunological checkpoint blockade in different types of metastatic cancers. Such data underscore that immunotherapy is one of the most promising strategies for cancer treatment. In addition, preclinical studies provide evidence that some cytotoxic drugs have the ability to stimulate the immune system, resulting in anti-tumor immune responses that contribute to clinical efficacy of these agents. These observations raise the hypothesis that the next step for cancer treatment is the combination of cytotoxic agents and immunotherapies. The present review aims to summarize the immune-mediated effects of chemotherapeutic agents and their clinical relevance, the biological and clinical features of immune checkpoint blockers and finally, the preclinical and clinical rationale for novel therapeutic strategies combining anticancer agents and immune checkpoint blockers.


Assuntos
Antineoplásicos/uso terapêutico , Terapia Combinada/métodos , Imunoterapia/métodos , Metástase Neoplásica/prevenção & controle , Neoplasias/terapia , Anticorpos Monoclonais/uso terapêutico , Humanos , Metástase Neoplásica/imunologia , Neoplasias/imunologia
15.
Cell Death Differ ; 22(2): 199-214, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24832470

RESUMO

The impact of gut microbiota in eliciting innate and adaptive immune responses beneficial for the host in the context of effective therapies against cancer has been highlighted recently. Chemotherapeutic agents, by compromising, to some extent, the intestinal integrity, increase the gut permeability and selective translocation of Gram-positive bacteria in secondary lymphoid organs. There, anticommensal pathogenic Th17 T-cell responses are primed, facilitating the accumulation of Th1 helper T cells in tumor beds after chemotherapy as well as tumor regression. Importantly, the redox equilibrium of myeloid cells contained in the tumor microenvironment is also influenced by the intestinal microbiota. Hence, the anticancer efficacy of alkylating agents (such as cyclophosphamide) and platinum salts (oxaliplatin, cis-platin) is compromised in germ-free mice or animals treated with antibiotics. These findings represent a paradigm shift in our understanding of the mode of action of many compounds having an impact on the host-microbe mutualism.


Assuntos
Antineoplásicos/farmacologia , Intestinos/microbiologia , Microbiota/imunologia , Neoplasias/imunologia , Neoplasias/microbiologia , Células Th17/imunologia , Animais , Antibacterianos/farmacologia , Humanos , Mucosa Intestinal/patologia , Camundongos
16.
Cell Death Dis ; 5: e1533, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25412311

RESUMO

In spite of the novel strategies to treat colon cancer, mortality rates associated with this disease remain consistently high. Tumour recurrence has been linked to the induction of resistance towards chemotherapy that involves cellular events that enable cancer cells to escape cell death. Treatment of colon cancer mainly implicates direct or indirect DNA-damaging agents and increased repair or tolerances towards subsequent lesions contribute to generate resistant populations. Resveratrol (RSV), a potent chemosensitising polyphenol, might share common properties with chemotherapeutic drugs through its indirect DNA-damaging effects reported in vitro. In this study, we investigated how RSV exerts its anticancer effects in models of colon cancer with a particular emphasis on the DNA-damage response (DDR; PIKKs-Chks-p53 signalling cascade) and its cellular consequences. We showed in vitro and in vivo that colon cancer models could progressively escape the repeated pharmacological treatments with RSV. We observed for the first time that this response was correlated with transient activation of the DDR, of apoptosis and senescence. In vitro, a single treatment with RSV induced a DDR correlated with S-phase delay and apoptosis, but prolonged treatments led to transient micronucleations and senescence phenotypes associated with polyploidisation. Ultimately, stable resistant populations towards RSV displaying higher degrees of ploidy and macronucleation as compared to parental cells emerged. We linked these transient effects and resistance emergence to the abilities of these cells to progressively escape RSV-induced DNA damage. Finally, we demonstrated that this DNA damage was triggered by an overproduction of reactive oxygen species (ROS) against which cancer cells could adapt under prolonged exposure to RSV. This study provides a pre-clinical analysis of the long-term effects of RSV and highlights ROS as main agents in RSV's indirect DNA-damaging properties and consequences in terms of anticancer response and potent resistance emergence.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Colo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Espécies Reativas de Oxigênio/metabolismo , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Colo/metabolismo , Colo/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Dano ao DNA , Histonas/genética , Histonas/metabolismo , Humanos , Poliploidia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ratos , Resveratrol , Fase S/efeitos dos fármacos , Fase S/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
17.
Cell Death Differ ; 21(12): 1914-24, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25124554

RESUMO

Liver X receptors (LXRs) have been proposed to have some anticancer properties, through molecular mechanisms that remain elusive. Here we report for the first time that LXR ligands induce caspase-1-dependent cell death of colon cancer cells. Caspase-1 activation requires Nod-like-receptor pyrin domain containing 3 (NLRP3) inflammasome and ATP-mediated P2 × 7 receptor activation. Surprisingly, LXRß is mainly located in the cytoplasm and has a non-genomic role by interacting with pannexin 1 leading to ATP secretion. Finally, LXR ligands have an antitumoral effect in a mouse colon cancer model, dependent on the presence of LXRß, pannexin 1, NLRP3 and caspase-1 within the tumor cells. Our results demonstrate that LXRß, through pannexin 1 interaction, can specifically induce caspase-1-dependent colon cancer cell death by pyroptosis.


Assuntos
Apoptose , Receptores Nucleares Órfãos/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Antineoplásicos/farmacologia , Proteínas de Transporte/metabolismo , Caspase 1/metabolismo , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Conexinas/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Hidrocarbonetos Fluorados/farmacologia , Receptores X do Fígado , Camundongos Endogâmicos BALB C , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transplante de Neoplasias , Proteínas do Tecido Nervoso/metabolismo , Receptores Nucleares Órfãos/agonistas , Sulfonamidas/farmacologia , Carga Tumoral/efeitos dos fármacos
18.
Cancer Res ; 74(16): 4217-21, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25074615

RESUMO

Distinct cytotoxic agents currently used in the oncological armamentarium mediate their clinical benefit by influencing, directly or indirectly, the immune system in such a way that innate and adaptive immunity contributes to the tumoricidal activity. Now, we bring up evidence that both arms of anticancer immunity can be triggered through the intervention of the intestinal microbiota. Alkylating agents, such as cyclophosphamide, set up the stage for enhanced permeability of the small intestine, facilitating the translocation of selected arrays of Gram-positive bacteria against which the host mounts effector pTh17 cells and memory Th1 responses. In addition, gut commensals, through lipopolysaccharide and other bacterial components, switch the tumor microenvironment, in particular the redox equilibrium and the TNF production of intratumoral myeloid cells during therapies with platinum salts or intratumoral TLR9 agonists combined with systemic anti-IL10R Ab respectively. Consequently, antibiotics can compromise the efficacy of certain chemotherapeutic or immunomodulatory regimens.


Assuntos
Bactérias/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Microbiota/imunologia , Animais , Bactérias/metabolismo , Humanos , Imunomodulação/imunologia , Transdução de Sinais
19.
Ann Oncol ; 25(7): 1442-1447, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24723487

RESUMO

BACKGROUND: Prognosis of unresectable glioblastoma (GB) remains poor, despite temozolomide (TMZ)-based chemoradiation. Activity of bevacizumab (BEV) and irinotecan (IRI) has been reported in recurrent disease. We evaluated BEV and IRI as neo-adjuvant and adjuvant treatment combined with TMZ-based chemoradiation for unresectable GB. PATIENTS AND METHODS: Patients with unresectable GB, age 18-70, IK ≥50 were eligible. The experimental arm (BEV/IRI) consisted of neo-adjuvant intravenous BEV, 10 mg/kg, and IRI, 125 mg/m(2), every 2 weeks for four cycles before radiotherapy (RT) (60 Gy), concomitant oral TMZ, 75 mg/m(2)/day, and BEV, 10 mg/kg every 2 weeks. Adjuvant BEV and IRI were given every 2 weeks for 6 months. The control arm consisted of concomitant oral TMZ, 75 mg/m(2)/day during RT, and 150-200 mg/m(2) for 5 days every 28 days for 6 months. The use of BEV was allowed at progression in the control arm. RESULTS: Patients (120) were included from April 2009 to January 2011. The working hypothesis was that treatment would increase the progression-free survival at 6 month (PFS-6) from 50% to 66%. The primary objective was not achieved, and only 30 out of 60 patients were alive without progression at 6 months (50.0% [IC95% (36.8; 63.1)] in the BEV/IRI arm when 37 out of 60 patients were required according to the Fleming decision rules. PFS-6 was 7.1 months in BEV/IRI versus 5.2 months in the control arm. The median overall survival was not different between the two arms (11.1 months). Main toxicities were three fatal intracranial bleedings, three bile duct or digestive perforations/infections (1 fatal), and six thrombotic episodes in the BEV/IRI arm, whereas there was one intracranial bleeding, two bile duct or digestive perforations/infections (1 fatal), and one thrombotic episode in the control arm. CONCLUSIONS: Neo-adjuvant and adjuvant BEV/IRI, combined with TMZ-radiation, is not recommended for further evaluation in the first-line treatment of unresectable GB. CLINICAL TRIAL REGISTRATION: Clinical trial registered under EUDRACT number 2008-002775-28 (NCT01022918).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Neoplasias Encefálicas/radioterapia , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Quimioterapia Adjuvante , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Feminino , Glioblastoma/radioterapia , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Temozolomida
20.
Opt Lett ; 38(22): 4686-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24322106

RESUMO

We present a pulsed fiber laser system with average power up to 265 W, pulse energy up to 10.6 mJ, pulse duration adjustable in the range 500 ps-500 ns, repetition rate fully controllable from single-shot operation up to 1 MHz, and the ability to control peak power independently of pulse energy. The system has a compact, all-spliced construction. Such a versatile laser will have wide applications in materials processing.

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