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1.
J Digit Imaging ; 33(5): 1091-1121, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31989390

RESUMO

Breast cancer is the most common type of malignancy diagnosed in women. Through early detection and diagnosis, there is a great chance of recovery and thereby reduce the mortality rate. Many preliminary tests like non-invasive radiological diagnosis using ultrasound, mammography, and MRI are widely used for the diagnosis of breast cancer. However, histopathological analysis of breast biopsy specimen is inevitable and is considered to be the golden standard for the affirmation of cancer. With the advancements in the digital computing capabilities, memory capacity, and imaging modalities, the development of computer-aided powerful analytical techniques for histopathological data has increased dramatically. These automated techniques help to alleviate the laborious work of the pathologist and to improve the reproducibility and reliability of the interpretation. This paper reviews and summarizes digital image computational algorithms applied on histopathological breast cancer images for nuclear atypia scoring and explores the future possibilities. The algorithms for nuclear pleomorphism scoring of breast cancer can be widely grouped into two categories: handcrafted feature-based and learned feature-based. Handcrafted feature-based algorithms mainly include the computational steps like pre-processing the images, segmenting the nuclei, extracting unique features, feature selection, and machine learning-based classification. However, most of the recent algorithms are based on learned features, that extract high-level abstractions directly from the histopathological images utilizing deep learning techniques. In this paper, we discuss the various algorithms applied for the nuclear pleomorphism scoring of breast cancer, discourse the challenges to be dealt with, and outline the importance of benchmark datasets. A comparative analysis of some prominent works on breast cancer nuclear atypia scoring is done using a benchmark dataset which enables to quantitatively measure and compare the different features and algorithms used for breast cancer grading. Results show that improvements are still required, to have an automated cancer grading system suitable for clinical applications.


Assuntos
Neoplasias da Mama , Interpretação de Imagem Assistida por Computador , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Aprendizado de Máquina , Reprodutibilidade dos Testes
2.
BMC Cancer ; 16: 473, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27412292

RESUMO

BACKGROUND: Maintenance treatment (MTx) in responders following first-line treatment has been investigated and practiced for many cancers. Modeling and simulation may support interpretation of interim data and development decisions. We aimed to develop a modeling framework to simulate overall survival (OS) for MTx in NSCLC using tumor growth inhibition (TGI) data. METHODS: TGI metrics were estimated using longitudinal tumor size data from two Phase III first-line NSCLC studies evaluating bevacizumab and erlotinib as MTx in 1632 patients. Baseline prognostic factors and TGI metric estimates were assessed in multivariate parametric models to predict OS. The OS model was externally validated by simulating a third independent NSCLC study (n = 253) based on interim TGI data (up to progression-free survival database lock). The third study evaluated pemetrexed + bevacizumab vs. bevacizumab alone as MTx. RESULTS: Time-to-tumor-growth (TTG) was the best TGI metric to predict OS. TTG, baseline tumor size, ECOG score, Asian ethnicity, age, and gender were significant covariates in the final OS model. The OS model was qualified by simulating OS distributions and hazard ratios (HR) in the two studies used for model-building. Simulations of the third independent study based on interim TGI data showed that pemetrexed + bevacizumab MTx was unlikely to significantly prolong OS vs. bevacizumab alone given the current sample size (predicted HR: 0.81; 95 % prediction interval: 0.59-1.09). Predicted median OS was 17.3 months and 14.7 months in both arms, respectively. These simulations are consistent with the results of the final OS analysis published 2 years later (observed HR: 0.87; 95 % confidence interval: 0.63-1.21). Final observed median OS was 17.1 months and 13.2 months in both arms, respectively, consistent with our predictions. CONCLUSIONS: A robust TGI-OS model was developed for MTx in NSCLC. TTG captures treatment effect. The model successfully predicted the OS outcomes of an independent study based on interim TGI data and thus may facilitate trial simulation and interpretation of interim data. The model was built based on erlotinib data and externally validated using pemetrexed data, suggesting that TGI-OS models may be treatment-independent. The results supported the use of longitudinal tumor size and TTG as endpoints in early clinical oncology studies.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Simulação por Computador , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Modelos Biológicos , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Cloridrato de Erlotinib/uso terapêutico , Feminino , Humanos , Quimioterapia de Manutenção/métodos , Masculino , Pessoa de Meia-Idade , Pemetrexede/uso terapêutico , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
3.
Angiogenesis ; 17(1): 163-77, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24221409

RESUMO

The angiogenic potential of solid tumors, or the ability to initiate neovasculature development from pre-existing host vessels, is facilitated by soluble factors secreted by tumor cells and involves breaching of extracellular matrix barriers, endothelial cell (EC) proliferation, migration and reassembly. We evaluated the angiogenic potential of human melanoma cell lines differing in their degree of aggressiveness, based on their ability to regulate directionally persistent EC migration. We observed that conditioned-medium (CM) of the aggressive melanoma cell line BLM induced a high effective migratory response in ECs, while CMs of Mel57 and 1F6 had an inhibitory effect. Further, the melanoma cell lines exhibited a varied expression profile of tissue inhibitor of metalloproteinase-3 (TIMP3), detectable in the CM. TIMP3 expression inversely correlated with aggressiveness of the melanoma cell line, and ability of the respective CMs to induce directed EC migration. Interestingly, TIMP3 expression was found to be silenced in the BLM cell line, concurrent with its role as a tumor suppressor. Treatment with recombinant human TIMP3 and CM of modified, TIMP3 expressing, BLM cells mitigated directional EC migration, while CM of TIMP3 silenced 1F6 cells induced directed EC migration. The functional implication of TIMP3 expression on tumor growth and angiogenic potential in melanoma was evaluated in vivo. We observed that TIMP3 expression reduced tumor growth, angiogenesis and macrophage infiltration of BLM tumors while silencing TIMP3 increased tumor growth and angiogenesis of 1F6 tumors. Taken together, our results demonstrate that TIMP3 expression correlates with inhibition of directionally persistent EC migration and adversely affects the angiogenic potential and growth of melanomas.


Assuntos
Movimento Celular , Regulação Neoplásica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Melanoma , Proteínas de Neoplasias/biossíntese , Neovascularização Patológica/metabolismo , Inibidor Tecidual de Metaloproteinase-3/biossíntese , Linhagem Celular Tumoral , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Melanoma/irrigação sanguínea , Melanoma/metabolismo , Melanoma/patologia , Neovascularização Patológica/patologia
4.
Am J Nephrol ; 40(1): 75-83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25059491

RESUMO

BACKGROUND: This analysis evaluated the incidence of and risk factors for bevacizumab-related proteinuria and assessed for any associated clinical sequelae, including renal function changes. METHODS: Patient-level adverse event and laboratory data from a pooled safety database were used to characterize alterations in urine protein excretion following interventional therapy ± bevacizumab in 17 randomized trials across multiple tumor types. Severity of renal function change was assessed using changes in serum creatinine concentration from baseline values. Potential predictors of proteinuria and the association between proteinuria and other adverse events were also investigated. RESULTS: Among 14,548 patients, the incidence of any-grade proteinuria was 8.2% (733/8,917) and 4.6% (257/5,631) in the bevacizumab and control groups, respectively; rates of grade ≥3 proteinuria were 1.4 and 0.2%. Post-baseline proteinuria grade and bevacizumab were associated with increased rates of renal dysfunction. Patients developing proteinuria had an increased rate of any-grade infection but not thromboembolic events. History of diabetes was the only examined risk factor that appeared to have a significant association with proteinuria development. CONCLUSIONS: This analysis confirmed a significant increase in the development of proteinuria during bevacizumab treatment. We also observed an increased rate of renal dysfunction associated with bevacizumab treatment and among subjects with proteinuria, although the dysfunction was generally mild. The development of proteinuria was also associated with a modest increase in risk of infection.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias/tratamento farmacológico , Proteinúria/induzido quimicamente , Insuficiência Renal/induzido quimicamente , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bevacizumab , Comorbidade , Diabetes Mellitus/epidemiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Renal/epidemiologia , Insuficiência Renal/metabolismo , Fatores de Risco , Fatores Sexuais , Adulto Jovem
5.
Carcinogenesis ; 34(11): 2629-38, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23764752

RESUMO

Whereas aberrant activation of canonical Wnt/ß-catenin signaling underlies the majority of colorectal cancer cases, the contribution of non-canonical Wnt signaling is unclear. As enhanced expression of the most extensively studied non-canonical Wnt ligand WNT5A is observed in various diseases including colon cancer, WNT5A is gaining attention nowadays. Numerous in vitro studies suggest modulating capacities of WNT5A on proliferation, differentiation, migration and invasion, affecting tumor and non-mutant cells. However, a possible contribution of WNT5A to colorectal cancer remains to be elucidated. We have analyzed WNT5A expression in colorectal cancer profiling data sets, altered WNT5A expression in colon cancer cells and used our inducible Wnt5a transgenic mouse model to gain more insight into the role of WNT5A in intestinal cancer. We observed that increased WNT5A expression is associated with poor prognosis of colorectal cancer patients. WNT5A knockdown in human colon cancer cells caused reduced directional migration, deregulated focal adhesion site formation and reduced invasion, whereas Wnt5a administration promoted the directional migration of colon cancer cells. Despite these observed protumorigenic activities of WNT5A, the induction of Wnt5a expression in intestinal tumors of Apc1638N mice was not sufficient to augment malignancy or metastasis by itself. In conclusion, WNT5A promotes adhesion sites to form in a focal fashion and promotes the directional migration and invasion of colon cancer cells. Although these activities appear insufficient by themselves to augment malignancy or metastasis in Apc1638N mice, they might explain the poor colon cancer prognosis associated with enhanced WNT5A expression.


Assuntos
Proteína da Polipose Adenomatosa do Colo/fisiologia , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica/patologia , Neoplasias do Colo/patologia , Intestinos/patologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Wnt/metabolismo , Animais , Apoptose , Western Blotting , Adesão Celular , Transformação Celular Neoplásica/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Adesões Focais , Humanos , Técnicas Imunoenzimáticas , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Invasividade Neoplásica , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteínas Wnt/genética , Proteína Wnt-5a
6.
IEEE J Biomed Health Inform ; 26(5): 2276-2287, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34826299

RESUMO

Nuclear atypia scoring (NAS), forms a significant factor in determining individualized treatment plans and also for the prognosis of the disease. Automation of cancer grading using quantitative image-based analysis of histopathological images can circumvent the shortcomings of the prevailing manual grading and can assist the pathologists in cancer diagnosis. However, developing such a robust classifier model require sufficient amount of annotated data, while the labeled histopathological images are scarce and expensive to procure as annotation forms a time-consuming and laborious task. Hence, a semi-supervised learning framework combined with the deep neural network based generative adversarial training, that can improve the performance of the classification model with limited annotated data, is proposed in this paper. The proposed NAS-SGAN model consists of discriminator and generator models that are trained in an adversarial manner using both labeled and unlabeled samples. The discriminator model is designed as an unsupervised model stacked over the supervised model sharing the model parameters and learns the data distribution by extracting the discriminative features. The generator model is trained over a stable feature matching objective function following a composite GAN architecture, and its for the first time the semi-supervised GAN model is explored for the grading of breast cancer. Experimental analysis shows that the proposed model could better discriminate different cancer grades thereby improving the robustness and accuracy of the system, even with limited amount of labeled samples.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Redes Neurais de Computação , Extratos Vegetais , Prognóstico , Aprendizado de Máquina Supervisionado
7.
Oncologist ; 15(12): 1329-34, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21147867

RESUMO

BACKGROUND: Vascular endothelial growth factor inhibitors have corticosteroid-sparing effects in patients with high-grade gliomas. We assessed corticosteroid use in patients with recurrent glioblastoma treated with bevacizumab (BEV) in the BRAIN study (J Clin Oncol 2009;27:4733-4740). METHODS: BRAIN was a phase II, multicenter, randomized, noncomparative trial of BEV alone (n = 85) or in combination with irinotecan (CPT-11) (n = 82) in adults with recurrent glioblastoma. Median corticosteroid dose for patients who used corticosteroids at baseline was summarized by treatment arm; the percentage of patients who had sustained (≥50% corticosteroid dose reduction for ≥50% of time on study drug) or complete (discontinuation of corticosteroid for ≥25% of time on study drug) reduction in corticosteroid dose overall and by objective response and progression-free survival was calculated. The incidence of corticosteroid-related adverse events was summarized. RESULTS: In each treatment group, 50% of patients were using systemic corticosteroids at baseline. The majority of those experienced a reduction in dose while receiving BEV-based therapy. Thirteen (30.2%) BEV and 20 (46.5%) BEV + CPT-11 patients had a sustained reduction of corticosteroid dose; 7 (16.3%) BEV and 9 (20.9%) BEV + CPT-11 patients had a complete reduction of corticosteroid dose. The majority of patients who had an objective response or progression-free survival >6 months experienced corticosteroid dose reduction. Approximately 64% of patients who used corticosteroids while receiving BEV-based therapy experienced infection. CONCLUSION: BEV may have corticosteroid-sparing effects in patients with recurrent glioblastoma. Corticosteroid reduction may positively affect patient health-related quality of life. Given the exploratory nature of the analyses in a noncomparative study, these results should be interpreted cautiously.


Assuntos
Corticosteroides/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Adulto , Anticorpos Monoclonais Humanizados , Bevacizumab , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/patologia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Taxa de Sobrevida , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Artif Intell Med ; 103: 101805, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32143801

RESUMO

Breast cancer is the most prevalent invasive type of cancer among women. The mortality rate of the disease can be reduced considerably through timely prognosis and felicitous treatment planning, by utilizing the computer aided detection and diagnosis techniques. With the advent of whole slide image (WSI) scanners for digitizing the histopathological tissue samples, there is a drastic increase in the availability of digital histopathological images. However, these samples are often unlabeled and hence they need labeling to be done through manual annotations by domain experts and experienced pathologists. But this annotation process required for acquiring high quality large labeled training set for nuclear atypia scoring is a tedious, expensive and time consuming job. Active learning techniques have achieved widespread acceptance in reducing this human effort in annotating the data samples. In this paper, we explore the possibilities of active learning on nuclear pleomorphism scoring over a non-Euclidean framework, the Riemannian manifold. Active learning technique adopted for the cancer grading is in the batch-mode framework, that adaptively identifies the apt batch size along with the batch of instances to be queried, following a submodular optimization framework. Samples for annotation are selected considering the diversity and redundancy between the pair of samples, based on the kernelized Riemannian distance measures such as log-Euclidean metrics and the two Bregman divergences - Stein and Jeffrey divergences. Results of the adaptive Batch Mode Active Learning on the Riemannian metric show a superior performance when compared with the state-of-the-art techniques for breast cancer nuclear pleomorphism scoring, as it makes use of the information from the unlabeled samples.


Assuntos
Neoplasias da Mama/patologia , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Humanos , Reconhecimento Automatizado de Padrão/métodos
9.
IEEE Trans Image Process ; 28(3): 1248-1260, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30346284

RESUMO

Breast cancer is found to be the most pervasive type of cancer among women. Computer aided detection and diagnosis of cancer at the initial stages can increase the chances of recovery and thus reduce the mortality rate through timely prognosis and adequate treatment planning. The nuclear atypia scoring or histopathological breast tumor grading remains to be a challenging problem due to the various artifacts and variabilities introduced during slide preparation and also because of the complexity in the structure of the underlying tissue patterns. Inspired by the success of symmetric positive definite (SPD) matrices in many of the challenging tasks in machine learning and computer vision, a sparse coding and dictionary learning on SPD matrices is proposed in this paper for the breast tumor grading. The proposed covariance-based SPD matrices form a Riemannian manifold and are represented as the sparse combination of Riemannian dictionary atoms. Non-linearity of the SPD manifold is tackled by embedding into the reproducing kernel Hilbert space using kernels derived from log-Euclidean metric, Jeffrey and Stein divergences and compared with the non-kernel-based affine invariant Riemannian metric. The novelty of the work lies in exploiting the kernel approach for the Hilbert space embedding of the Riemannian manifold, that can achieve a better discrimination of the breast cancer tissues, following a sparse representation over learned dictionaries and henceforth it outperforms many of the state-of-the-art algorithms in breast cancer grading in terms of quantitative and qualitative analysis.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Núcleo Celular/classificação , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina Supervisionado , Algoritmos , Artefatos , Neoplasias da Mama/patologia , Bases de Dados Factuais , Feminino , Histocitoquímica , Humanos
10.
Clin Cancer Res ; 24(19): 4680-4693, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29945998

RESUMO

Purpose: Toca 511 is a gammaretroviral replicating vector encoding cytosine deaminase that selectively infects tumor cells and converts the antifungal drug 5-fluorocytosine into the antineoplastic drug 5-fluorouracil, which directly kills tumor cells and stimulates antitumor immune responses. As part of clinical monitoring of phase I clinical trials in recurrent high-grade glioma, we have performed extensive molecular analyses of patient specimens to track vector fate.Patients and Methods: Toca 511 and Toca FC (extended-release 5-fluorocytosine) have been administered to 127 high-grade glioma patients across three phase I studies. We measured Toca 511 RNA and DNA levels in available body fluids and tumor samples from patients to assess tumor specificity. We mapped Toca 511 integration sites and sequenced integrated Toca 511 genomes from patient samples with detectable virus. We measured Toca 511 levels in a diverse set of tissue samples from one patient.Results: Integrated Toca 511 is commonly detected in tumor samples and is only transiently detected in blood in a small fraction of patients. There was no believable evidence for clonal expansion of cells with integrated Toca 511 DNA, or preferential retrieval of integration sites near oncogenes. Toca 511 sequence profiles suggest most mutations are caused by APOBEC cytidine deaminases acting during reverse transcription. Tissue samples from a single whole-body autopsy affirm Toca 511 tumor selectivity.Conclusions: Toca 511 and Toca FC treatment was not associated with inappropriate integration sites and clonal expansion. The vector is tumor-selective and persistent in patients who received Toca 511 injections. Clin Cancer Res; 24(19); 4680-93. ©2018 AACR.


Assuntos
Terapia Genética , Vetores Genéticos/administração & dosagem , Glioma/tratamento farmacológico , Pró-Fármacos/administração & dosagem , Idoso , Animais , Autopsia , Linhagem Celular Tumoral , Citosina Desaminase/genética , Modelos Animais de Doenças , Feminino , Flucitosina/administração & dosagem , Flucitosina/química , Fluoruracila/administração & dosagem , Fluoruracila/química , Vetores Genéticos/efeitos adversos , Vetores Genéticos/sangue , Vetores Genéticos/genética , Glioma/sangue , Glioma/genética , Glioma/patologia , Humanos , Masculino , Camundongos , Pró-Fármacos/efeitos adversos , Retroviridae/genética
11.
Neuro Oncol ; 20(10): 1383-1392, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29762717

RESUMO

Background: Vocimagene amiretrorepvec (Toca 511) is an investigational gamma-retroviral replicating vector encoding cytosine deaminase that, when used in combination with extended-release 5-fluorocytosine (Toca FC), results preclinically in local production of 5-fluorouracil, depletion of immune-suppressive myeloid cells, and subsequent induction of antitumor immunity. Recurrent high-grade glioma (rHGG) patients have a high unmet need for effective therapies that produce durable responses lasting more than 6 months. In this setting, relapse is nearly universal and most responses are transient. Methods: In this Toca 511 ascending-dose phase I trial (NCT01470794), HGG patients who recurred after standard of care underwent surgical resection and received Toca 511 injected into the resection cavity wall, followed by orally administered cycles of Toca FC. Results: Among 56 patients, durable complete responses were observed. A subgroup was identified based on Toca 511 dose and entry requirements for the follow-up phase III study. In this subgroup, which included both isocitrate dehydrogenase 1 (IDH1) mutant and wild-type tumors, the durable response rate is 21.7%. Median duration of follow-up for responders is 35.7+ months. As of August 25, 2017, all responders remain in response and are alive 33.9+ to 52.2+ months after Toca 511 administration, suggesting a positive association of durable response with overall survival. Conclusions: Multiyear durable responses have been observed in rHGG patients treated with Toca 511 + Toca FC in a phase I trial, and the treatment will be further evaluated in a randomized phase III trial. Among IDH1 mutant patients treated at first recurrence, there may be an enrichment of complete responders.


Assuntos
Neoplasias Encefálicas/terapia , Citosina Desaminase/metabolismo , Sinergismo Farmacológico , Flucitosina/uso terapêutico , Vetores Genéticos/administração & dosagem , Glioma/terapia , Retroviridae/genética , Antimetabólitos/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Terapia Combinada , Citosina Desaminase/genética , Fluoruracila/metabolismo , Seguimentos , Vetores Genéticos/genética , Glioma/genética , Glioma/imunologia , Glioma/patologia , Humanos , Prognóstico , Taxa de Sobrevida
12.
Oncogene ; 24(33): 5226-34, 2005 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-15897911

RESUMO

Tyrosinase-related protein (TRP)-2 is not only expressed on glioma cells, but is naturally processed and presented by their surface MHC molecules and is recognized by TRP-2-specific cytotoxic T cells. After active immunotherapy, we detected TRP-2-specific cytotoxic T lymphocyte (CTL) activity in patients' peripheral blood mononuclear cells (PBMC). Tumor cells from postvaccination resections showed significantly lower TRP-2 expression and higher sensitivity to carboplatin and temozolomide than those autologous cell lines from prevaccination resections in two patients who demonstrated CTL response to TRP-2. One of two patients underwent treatment with temozolomide after recurrence and responded dramatically. TRP-2-transfected cell line (TRP-2-U373) resulted in significant drug resistance to carboplatin and temozolomide compared to wild-type U-373 (W-U373). There was no significant difference, however, in the mRNA expression of other common drug resistance related proteins, such as BCRP-1, MGMT, MDR-1, MRP-1 and MRP-3, after TRP-2 transfection. TRP-2-U373 tumor cells were immunoselected by a TRP-2-specific CTL line. The immunoselected cells (IS-TRP-2-U373) demonstrated significantly increased sensitivity to carboplatin and temozolomide compared to TRP-2-U373. For the first time, we provide evidence that immunological targeting of tumor-associated antigen TRP-2 significantly increases sensitivity to chemotherapy.


Assuntos
Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/terapia , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/imunologia , Glioma/imunologia , Glioma/terapia , Oxirredutases Intramoleculares/imunologia , Linfócitos T Citotóxicos/imunologia , Antígenos de Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carboplatina/farmacologia , Terapia Combinada , Dano ao DNA , Dacarbazina/farmacologia , Interações Medicamentosas , Humanos , Imunoterapia Ativa , Temozolomida , Transfecção , Resultado do Tratamento , Células Tumorais Cultivadas
13.
Oncoimmunology ; 5(10): e1219826, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27853641

RESUMO

Although melanoma progression and staging is clinically well characterized, a large variation is observed in pathogenesis, progression, and therapeutic responses. Clearly, intrinsic characteristics of melanoma cells contribute to this variety. An important factor, in both progression of the disease and response to therapy, is the tumor-associated vasculature. We postulate that melanoma cells communicate with endothelial cells (ECs) in order to establish a functional and supportive blood supply. We investigated the angiogenic potential of human melanoma cell lines by monitoring the survival of ECs upon exposure to melanoma conditioned medium (CM), under restrictive conditions. We observed long-term (up to 72 h) EC survival under hypoxic conditions upon treatment with all melanoma CMs. No such survival effect was observed with the CM of melanocytes. The CM of pancreatic and breast tumor cell lines did not show a long-term survival effect, suggesting that the survival factor is specific to melanoma cells. Furthermore, all size fractions (up to < 1 kDa) of the melanoma CM induced long-term survival of ECs. The survival effect observed by the < 1 kDa fraction excludes known pro-angiogenic factors. Heat inactivation and enzymatic digestion of the CM did not inactivate the survival factor. Global gene expression and pathway analysis suggest that this effect is mediated in part via the AKT and p38 MAPK/ ERK-1/2 signaling axis. Taken together, these data indicate the production of (a) survival factor/s (< 1 kDa) by melanoma cell lines, which enables long-term survival of ECs and promotes melanoma-induced angiogenesis.

14.
Oncotarget ; 7(16): 21922-38, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-26942883

RESUMO

Cell signaling is dependent on the balance between phosphorylation of proteins by kinases and dephosphorylation by phosphatases. This balance if often disrupted in colorectal cancer (CRC), leading to increased cell proliferation and invasion. For many years research has focused on the role of kinases as potential oncogenes in cancer, while phosphatases were commonly assumed to be tumor suppressive. However, this dogma is currently changing as phosphatases have also been shown to induce cancer growth. One of these phosphatases is protein tyrosine phosphatase 1B (PTP1B). Here we report that the expression of PTP1B is increased in colorectal cancer as compared to normal tissue, and that the intrinsic enzymatic activity of the protein is also enhanced. This suggests a role for PTP1B phosphatase activity in CRC formation and progression. Furthermore, we found that increased PTP1B expression is correlated to a worse patient survival and is an independent prognostic marker for overall survival and disease free survival. Knocking down PTP1B in CRC cell lines results in a less invasive phenotype with lower adhesion, migration and proliferation capabilities. Together, these results suggest that inhibition of PTP1B activity is a promising new target in the treatment of colorectal cancer and the prevention of metastasis.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento
15.
Eur J Cancer ; 53: 135-43, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26707830

RESUMO

AIMS: Several anti-tumour properties have been ascribed to the tissue inhibitor of matrix metalloproteinases-3 (TIMP3) gene, including inhibition of neovascularisation in tumour xenografts. Reduced protein expression has been linked to promoter hypermethylation and allelic loss of heterozygosity in various human malignancies. In melanoma-positive lymph nodes from patients, we evaluated the association between TIMP3 expression, vessel density, macrophage infiltration and potential correlations with disease-free survival (DFS) and overall survival (OS). PATIENTS AND METHODS: TIMP3 expression was analysed by immunohistochemistry (IHC) in melanoma lymph node biopsies of stage III melanoma patients (n = 43). Blood vessel density and macrophage infiltration were quantitatively assessed and correlation with TIMP3 expression was investigated. Methylation status of the gene promoter was determined using methylation-specific polymerase chain reaction (MSP). Protein expression and promoter methylation status were investigated for associations with DFS and OS. RESULTS: Reduced expression of TIMP3, as determined by IHC, was observed in 74% of the cases (32 in 43). A significant inverse correlation was observed between TIMP3 expression and vessel density (p = 0.031). Correlation between TIMP3 expression and macrophage infiltration was not statistically significant (p = 0.369). MSP analysis revealed methylation of the gene promoter in 18% (7 in 38) of the analysed cases. No differences in OS and DFS were observed between cases with high and low TIMP3 expression. Gene promoter methylation was significantly associated with both poor 5-year DFS (p = 0.024) and OS (p = 0.034). CONCLUSIONS: Our data indicate that TIMP3 is a dominant negative regulator of angiogenesis in cutaneous melanoma and gene silencing by promoter methylation is associated with poor outcome.


Assuntos
Biomarcadores Tumorais/metabolismo , Macrófagos/fisiologia , Melanoma/irrigação sanguínea , Neoplasias Cutâneas/irrigação sanguínea , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Idoso , Estudos de Coortes , Metilação de DNA/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Melanoma/metabolismo , Melanoma/mortalidade , Pessoa de Meia-Idade , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Prognóstico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/mortalidade
16.
Oncotarget ; 7(45): 73525-73540, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27716613

RESUMO

Colorectal cancer (CRC) is the second most common cause of cancer-related death, encouraging the search for novel therapeutic targets affecting tumor cell proliferation and migration. These cellular processes are under tight control of two opposing groups of enzymes; kinases and phosphatases. Aberrant activity of kinases is observed in many forms of cancer and as phosphatases counteract such "oncogenic" kinases, it is generally assumed that phosphatases function as tumor suppressors. However, emerging evidence suggests that the lipid phosphatase SH2-domain-containing 5 inositol phosphatase (SHIP2), encoded by the INPPL1 gene, may act as an oncogene. Just like the well-known tumor suppressor gene Phosphatase and Tensin Homolog (PTEN) it hydrolyses phosphatidylinositol (3,4,5) triphosphate (PI(3,4,5)P3). However, unlike PTEN, the reaction product is PI(3,4)P2, which is required for full activation of the downstream protein kinase B (PKB/Akt), suggesting that SHIP2, in contrast to PTEN, could have a tumor initiating role through PKB activation. In this work, we investigated the role of SHIP2 in colorectal cancer. We found that SHIP2 and INPPL1 expression is increased in colorectal cancer tissue in comparison to adjacent normal tissue, and this is correlated with decreased patient survival. Moreover, SHIP2 is more active in colorectal cancer tissue, suggesting that SHIP2 can induce oncogenesis in colonic epithelial cells. Furthermore, in vitro experiments performed on colorectal cancer cell lines shows an oncogenic role for SHIP2, by enhancing chemoresistance, cell migration, and cell invasion. Together, these data indicate that SHIP2 expression contributes to the malignant potential of colorectal cancer, providing a possible target in the fight against this devastating disease.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Oncogenes , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Movimento Celular , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Ativação Enzimática , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Mutação , Gradação de Tumores , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
Eur J Cancer ; 66: 34-46, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27522248

RESUMO

AIMS: Malignant melanoma is the most aggressive form of skin cancer, and metastatic dissemination to regional and visceral sites is responsible for the majority of melanoma-related mortalities. In a recent study by our group, we observed reduced expression of tissue inhibitor of metalloproteinase-3 (TIMP3) in the majority of stage III melanoma samples studied. TIMP3 has been reported as a tumour suppressor in several human malignancies, with reduced expression correlating with poor clinical outcome. In this study, we investigated the changes in TIMP3 expression during melanoma progression. PATIENTS AND METHODS: TIMP3 expression was analysed by immunohistochemistry in sequential archived tumour material from stage I/II, stage III and stage IV samples from melanoma patients (n = 33). Protein expression was investigated for associations with disease-free survival and overall survival. Methylation status of the gene promoter was determined using methylation-specific PCR. In vitro assays were used to investigate the functional consequences of TIMP3 expression on behavioural aspects of melanoma cells. RESULTS: We show that TIMP3 expression decreases with melanoma progression although no significant clinical associations were obtained. Analysis of the status of promoter methylation using methylation-specific PCR revealed it to be a low-frequency event in melanoma. Additionally, through gene modulation experiments in melanoma cell lines, we show that TIMP3 negatively regulates cell migration, invasion and anoikis resistance. CONCLUSIONS: Collectively, our data suggests that TIMP3 functions as a tumour suppressor in melanoma and negatively regulates several aspects of the metastatic cascade.


Assuntos
Melanoma/patologia , Neoplasias Cutâneas/patologia , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Adulto , Idoso , Movimento Celular/fisiologia , Metilação de DNA , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/metabolismo , Melanoma/mortalidade , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/mortalidade
18.
Sci Transl Med ; 8(341): 341ra75, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27252174

RESUMO

Toca 511 (vocimagene amiretrorepvec) is an investigational nonlytic, retroviral replicating vector (RRV) that delivers a yeast cytosine deaminase, which converts subsequently administered courses of the investigational prodrug Toca FC (extended-release 5-fluorocytosine) into the antimetabolite 5-fluorouracil. Forty-five subjects with recurrent or progressive high-grade glioma were treated. The end points of this phase 1, open-label, ascending dose, multicenter trial included safety, efficacy, and molecular profiling; survival was compared to a matching subgroup from an external control. Overall survival for recurrent high-grade glioma was 13.6 months (95% confidence interval, 10.8 to 20.0) and was statistically improved relative to an external control (hazard ratio, 0.45; P = 0.003). Tumor samples from subjects surviving more than 52 weeks after Toca 511 delivery disproportionately displayed a survival-related mRNA expression signature, identifying a potential molecular signature that may correlate with treatment-related survival rather than being prognostic. Toca 511 and Toca FC show excellent tolerability, with RRV persisting in the tumor and RRV control systemically. The favorable assessment of Toca 511 and Toca FC supports confirmation in a randomized phase 2/3 trial (NCT02414165).


Assuntos
Vetores Genéticos/genética , Glioma/tratamento farmacológico , Glioma/patologia , Retroviridae/genética , Intervalos de Confiança , Citosina Desaminase/genética , Citosina Desaminase/metabolismo , Flucitosina/metabolismo , Fluoruracila/metabolismo , Vetores Genéticos/administração & dosagem , Glioma/mortalidade , Pró-Fármacos/administração & dosagem , Pró-Fármacos/metabolismo , Pró-Fármacos/uso terapêutico , RNA Mensageiro/genética
19.
J Neurosurg ; 103(5 Suppl): 451-3, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16302619

RESUMO

In this report the authors describe the clinical features of a rare neonatal anaplastic astrocytoma in the setting of in vitro fertilization (IVF). The infant had been conceived using IVF and was born full term to a 29-year-old prima gravida mother. At birth, the baby boy was irritable and demonstrated poor feeding. Cranial ultrasonography and magnetic resonance imaging revealed an echogenic mass in the left hemisphere with midline shift and hydrocephalus. Grosstotal resection of an anaplastic astrocytoma was followed by chemotherapy with temozolomide and vincristine. Previous cases of neonatal brain tumors occurring in the setting of assisted reproduction are reviewed. A possible association between IVF and congenital neuroepithelial tumors is highlighted.


Assuntos
Astrocitoma/congênito , Neoplasias Encefálicas/congênito , Fertilização in vitro/efeitos adversos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Astrocitoma/tratamento farmacológico , Astrocitoma/cirurgia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/cirurgia , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Gravidez , Temozolomida , Vincristina/administração & dosagem
20.
Clin Cancer Res ; 10(16): 5316-26, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15328167

RESUMO

PURPOSE: Although the development of immune-based therapies for various cancers including malignant glioma has been heralded with much hope and optimism, objective clinical improvements in most vaccinated cancer patients have not been realized. To broaden the search for vaccine-induced benefits, we examined synergy of vaccines with conventional chemotherapy. EXPERIMENTAL DESIGN: Survival and progression times were analyzed retrospectively in 25 vaccinated (13 with and 12 without subsequent chemotherapy) and 13 nonvaccinated de novo glioblastoma (GBM) patients receiving chemotherapy. Immune responsiveness and T-cell receptor excision circle (TREC) content within CD8+ T cells (CD8+ TRECs) was determined in vaccinated patients. RESULTS: Vaccinated patients receiving subsequent chemotherapy exhibited significantly longer times to tumor recurrence after chemotherapy relative to their own previous recurrence times, as well as significantly longer postchemotherapy recurrence times and survival relative to patients receiving isolated vaccination or chemotherapy. Patients exhibiting objective (>50%) tumor regression, extremely rare in de novo GBM, were also confined to the vaccine + chemotherapy group. Prior tumor behavior, demographic factors, other treatment variables, distribution of vaccine responders, and patients with high CD8+ TRECs all failed to account for these differences in clinical outcome. Within all GBM patients receiving post-vaccine chemotherapy, however, CD8+ TRECs predicted significantly longer chemotherapeutic responses, revealing a strong link between the predominant T-cell effectors in GBM and tumor chemosensitivity. CONCLUSIONS: We propose that therapeutic vaccination synergizes with subsequent chemotherapy to elicit tangible clinical benefits for GBM patients.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/imunologia , Vacinas Anticâncer/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/imunologia , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Craniotomia , Primers do DNA , Progressão da Doença , Feminino , Seguimentos , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Estudos Retrospectivos , Análise de Sobrevida , Linfócitos T/imunologia , Resultado do Tratamento
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