Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Cancer ; 128(2): 344-352, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34550601

RESUMO

BACKGROUND: Disparity in mental health care among cancer patients remains understudied. METHODS: A large, retrospective, single tertiary-care institution cohort study was conducted based on deidentified electronic health record data of 54,852 adult cancer patients without prior mental health diagnosis (MHD) diagnosed at the University of California, San Francisco between January 2012 and September 2019. The exposure of interest was early-onset MHD with or without psychotropic medication (PM) within 12 months of cancer diagnosis and primary outcome was all-cause mortality. RESULTS: There were 8.2% of patients who received a new MHD at a median of 197 days (interquartile range, 61-553) after incident cancer diagnosis; 31.0% received a PM prescription; and 3.7% a mental health-related visit (MHRV). There were 62.6% of patients who were non-Hispanic White (NHW), 10.8% were Asian, 9.8% were Hispanic, and 3.8% were Black. Compared with NHWs, minority cancer patients had reduced adjusted odds of MHDs, PM prescriptions, and MHRVs, particularly for generalized anxiety (Asian odds ratio [OR], 0.66, 95% CI, 0.55-0.78; Black OR, 0.60, 95% CI, 0.45-0.79; Hispanic OR, 0.72, 95% CI, 0.61-0.85) and selective serotonin-reuptake inhibitors (Asian OR, 0.43, 95% CI, 0.37-0.50; Black OR, 0.51, 95% CI, 0.40-0.61; Hispanic OR, 0.79, 95% CI, 0.70-0.89). New early MHD with PM was associated with elevated all-cause mortality (12-24 months: hazard ratio [HR], 1.43, 95% CI, 1.25-1.64) that waned by 24 to 36 months (HR, 1.18, 95% CI, 0.95-1.45). CONCLUSIONS: New mental health diagnosis with PM was a marker of early mortality among cancer patients. Minority cancer patients were less likely to receive documentation of MHDs or treatment, which may represent missed opportunities to identify and treat cancer-related mental health conditions.


Assuntos
Saúde Mental , Neoplasias , Adulto , Estudos de Coortes , Registros Eletrônicos de Saúde , Humanos , Neoplasias/diagnóstico , Estudos Retrospectivos
2.
Proc Natl Acad Sci U S A ; 114(41): E8685-E8694, 2017 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-28973887

RESUMO

The molecular underpinnings of invasion, a hallmark of cancer, have been defined in terms of individual mediators but crucial interactions between these mediators remain undefined. In xenograft models and patient specimens, we identified a c-Met/ß1 integrin complex that formed during significant invasive oncologic processes: breast cancer metastases and glioblastoma invasive resistance to antiangiogenic VEGF neutralizing antibody, bevacizumab. Inducing c-Met/ß1 complex formation through an engineered inducible heterodimerization system promoted features crucial to overcoming stressors during metastases or antiangiogenic therapy: migration in the primary site, survival under hypoxia, and extravasation out of circulation. c-Met/ß1 complex formation was up-regulated by hypoxia, while VEGF binding VEGFR2 sequestered c-Met and ß1 integrin, preventing their binding. Complex formation promoted ligand-independent receptor activation, with integrin-linked kinase phosphorylating c-Met and crystallography revealing the c-Met/ß1 complex to maintain the high-affinity ß1 integrin conformation. Site-directed mutagenesis verified the necessity for c-Met/ß1 binding of amino acids predicted by crystallography to mediate their extracellular interaction. Far-Western blotting and sequential immunoprecipitation revealed that c-Met displaced α5 integrin from ß1 integrin, creating a complex with much greater affinity for fibronectin (FN) than α5ß1. Thus, tumor cells adapt to microenvironmental stressors induced by metastases or bevacizumab by coopting receptors, which normally promote both cell migration modes: chemotaxis, movement toward concentrations of environmental chemoattractants, and haptotaxis, movement controlled by the relative strengths of peripheral adhesions. Tumor cells then redirect these receptors away from their conventional binding partners, forming a powerful structural c-Met/ß1 complex whose ligand-independent cross-activation and robust affinity for FN drive invasive oncologic processes.


Assuntos
Neoplasias da Mama/secundário , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/secundário , Integrina beta1/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Apoptose/efeitos dos fármacos , Bevacizumab/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Feminino , Fibronectinas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Integrina beta1/genética , Camundongos , Invasividade Neoplásica , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Breast Cancer Res Treat ; 155(3): 431-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26860947

RESUMO

The central role of HER2 as the disease driver and HER3 as its essential partner has made them rational targets for the treatment of HER2-amplifed breast cancers, and there is considerable interest in developing highly effective treatment regimens for this disease that consist of targeted therapies alone. Much of these efforts are focused on dual targeting approaches, particularly dual targeting of the HER2-HER3 tumor driver complex itself, or vertical combinations that target downstream PI3K or Akt in addition to HER2. There is also potential in lateral combinations based on evidence implicating cross-talk with other membrane receptor systems, particularly integrins, and such lateral combinations can potentially involve either HER2 or HER3. We established a preclinical model of targeting HER3 using doxycycline-inducible shRNA and determined the efficacy of a ß1 integrin inhibitor in combination with targeting HER3. We report that targeting HER3 and ß1 integrin provides a particularly effective combination therapy approach for HER2-amplified cancers, surpassing the combination of HER2 and ß1 integrin targeting, and evading some of the safety concerns associated with direct HER2-targeting. This further validates HER3 as a major hub mediating the tumorigenic functions of HER2 and identifies it as a high value target for lateral combination therapy strategies.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doxiciclina/administração & dosagem , Integrina beta1/genética , Receptor ErbB-2/genética , Receptor ErbB-3/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Integrina beta1/efeitos dos fármacos , Terapia de Alvo Molecular , Fosfatidilinositol 3-Quinases/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
4.
Oncology (Williston Park) ; 29(6): 446-58, 460-1, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26089220

RESUMO

Ductal carcinoma in situ (DCIS) is a breast neoplasm with potential for progression to invasive cancer. Management commonly involves excision, radiotherapy, and hormonal therapy. Surgical assessment of regional lymph nodes is rarely indicated except in cases of microinvasion or mastectomy. Radiotherapy is employed for local control in breast conservation, although it may be omitted for select low-risk situations. Several radiotherapy techniques exist beyond standard whole-breast irradiation (ie, partial-breast irradiation [PBI], hypofractionated whole-breast radiation); evidence for these is evolving. We present an update of the American College of Radiology (ACR) Appropriateness Criteria® for the management of DCIS. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions, which are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review includes an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi technique) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.


Assuntos
Neoplasias da Mama/terapia , Carcinoma Intraductal não Infiltrante/terapia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/patologia , Carcinoma Lobular/terapia , Feminino , Humanos , Imageamento por Ressonância Magnética , Mamografia , Mastectomia , Mastectomia Segmentar , Invasividade Neoplásica , Dosagem Radioterapêutica , Radioterapia Adjuvante , Biópsia de Linfonodo Sentinela , Tamoxifeno/uso terapêutico
5.
Oncology (Williston Park) ; 28(2): 157-64, C3, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24701707

RESUMO

Although both breast-conserving surgery and mastectomy generally provide excellent local-regional control of breast cancer, local-regional recurrence (LRR) does occur. Predictors for LRR include patient, tumor, and treatment-related factors. Salvage after LRR includes coordination of available modalities, including surgery, radiation, chemotherapy, and hormonal therapy, depending on the clinical scenario. Management recommendations for breast cancer LRR, including patient scenarios, are reviewed, and represent evidence-based data and expert opinion of the American College of Radiology Appropriateness Criteria Expert Panel on LRR.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel.The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.


Assuntos
Neoplasias da Mama/terapia , Recidiva Local de Neoplasia/terapia , Terapia de Salvação/métodos , Adulto , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Guias de Prática Clínica como Assunto
6.
Breast Cancer Res ; 15(4): R60, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23883667

RESUMO

INTRODUCTION: Ductal carcinoma in situ (DCIS) is characterized by non-invasive cancerous cell growth within the breast ducts. Although radiotherapy is commonly used in the treatment of DCIS, the effect and molecular mechanism of ionizing radiation (IR) on DCIS are not well understood, and invasive recurrence following radiotherapy remains a significant clinical problem. This study investigated the effects of IR on a clinically relevant model of Akt-driven DCIS and identified possible molecular mechanisms underlying invasive progression in surviving cells. METHODS: We measured the level of phosphorylated-Akt (p-Akt) in a cohort of human DCIS specimens by immunohistochemistry (IHC) and correlated it with recurrence risk. To model human DCIS, we used Akt overexpressing human mammary epithelial cells (MCF10A-Akt) which, in three-dimensional laminin-rich extracellular matrix (lrECM) and in vivo, form organotypic DCIS-like lesions with lumina expanded by pleiomorphic cells contained within an intact basement membrane. In a population of cells that survived significant IR doses in three-dimensional lrECM, a malignant phenotype emerged creating a model for invasive recurrence. RESULTS: P-Akt was up-regulated in clinical DCIS specimens and was associated with recurrent disease. MCF10A-Akt cells that formed DCIS-like structures in three-dimensional lrECM showed significant apoptosis after IR, preferentially in the luminal compartment. Strikingly, when cells that survived IR were repropagated in three-dimensional lrECM, a malignant phenotype emerged, characterized by invasive activity, up-regulation of fibronectin, α5ß1-integrin, matrix metalloproteinase-9 (MMP-9) and loss of E-cadherin. In addition, IR induced nuclear translocation and binding of nuclear factor-kappa B (NF-κB) to the ß1-integrin promoter region, associated with up-regulation of α5ß1-integrins. Inhibition of NF-κB or ß1-integrin signaling abrogated emergence of the invasive activity. CONCLUSIONS: P-Akt is up-regulated in some human DCIS lesions and is possibly associated with recurrence. MCF10A-Akt cells form organotypic DCIS-like lesions in three-dimensional lrECM and in vivo, and are a plausible model for some forms of human DCIS. A population of Akt-driven DCIS-like spheroids that survive IR progresses to an invasive phenotype in three-dimensional lrECM mediated by ß1-integrin and NF-κB signaling.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Integrina beta1/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Animais , Apoptose/genética , Apoptose/efeitos da radiação , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Carcinoma Intraductal não Infiltrante/metabolismo , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/radioterapia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ativação Enzimática , Feminino , Xenoenxertos , Humanos , Integrina beta1/genética , Camundongos , Invasividade Neoplásica , Recidiva Local de Neoplasia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Radiação Ionizante , Esferoides Celulares , Células Tumorais Cultivadas , Regulação para Cima
7.
Ann Surg Oncol ; 20(9): 2873-80, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23812769

RESUMO

BACKGROUND: Shortened courses of radiation therapy have been shown to be similarly effective to whole-breast external-beam radiation therapy (WB-EBRT) in terms of local control. We sought to analyze, from a societal perspective, the cost-effectiveness of two radiation strategies for early-stage invasive breast cancer: single-dose intraoperative radiation therapy (IORT) and the standard 6-week course of WB-EBRT. METHODS: We developed a Markov decision-analytic model to evaluate these treatment strategies in terms of life expectancy, quality-adjusted life years (QALYs), costs, and the incremental cost-effectiveness ratio over 10 years. RESULTS: IORT single-dose intraoperative radiation therapy was the dominant, more cost-effective strategy, providing greater quality-adjusted life years at a decreased cost compared with 6-week WB-EBRT. The model was sensitive to health state utilities and recurrence rates, but not costs. IORT was either the preferred or dominant strategy across all sensitivity analyses. The two-way sensitivity analyses demonstrate the need to accurately determine utility values for the two forms of radiation treatment and to avoid indiscriminate use of IORT. CONCLUSIONS: With less cost and greater QALYs than WB-EBRT, IORT is the more valuable strategy. IORT offers a unique example of new technology that is less costly than the current standard of care option but offers similar efficacy. Even when considering the capital investment for the equipment ($425 K, low when compared with the investments required for robotic surgery or high-dose-rate brachytherapy), which could be recouped after 3-4 years conservatively, these results support IORT as a change in practice for treating early-stage invasive breast cancer.


Assuntos
Braquiterapia/economia , Neoplasias da Mama/economia , Análise Custo-Benefício , Cadeias de Markov , Recidiva Local de Neoplasia/economia , Radioterapia Adjuvante/economia , Braquiterapia/mortalidade , Neoplasias da Mama/mortalidade , Neoplasias da Mama/radioterapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Cuidados Intraoperatórios , Metástase Linfática , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/radioterapia , Estadiamento de Neoplasias , Prognóstico , Qualidade de Vida , Radioterapia Adjuvante/mortalidade , Taxa de Sobrevida
8.
Breast Cancer Res ; 13(4): R84, 2011 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-21884573

RESUMO

INTRODUCTION: The overexpression of human epidermal growth factor receptor (HER)-2 in 20% of human breast cancers and its association with aggressive growth has led to widespread use of HER2-targeted therapies, such as trastuzumab (T) and lapatinib (L). Despite the success of these drugs, their efficacy is limited in patients whose tumors demonstrate de novo or acquired resistance to treatment. The ß1 integrin resides on the membrane of the breast cancer cell, activating several elements of breast tumor progression including proliferation and survival. METHODS: We developed a panel of HER2-overexpressing cell lines resistant to L, T, and the potent LT combination through long-term exposure and validated these models in 3D culture. Parental and L/T/LT-resistant cells were subject to HER2 and ß1 integrin inhibitors in 3D and monitored for 12 days, followed by quantification of colony number. Parallel experiments were conducted where cells were either stained for Ki-67 and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) or harvested for protein and analyzed by immunoblot. Results were subjected to statistical testing using analysis of variance and linear contrasts, followed by adjustment with the Sidak method. RESULTS: Using multiple cell lines including BT474 and HCC1954, we reveal that in L and LT resistance, where phosphorylation of EGFR/HER1, HER2, and HER3 are strongly inhibited, kinases downstream of ß1 integrin--including focal adhesion kinase (FAK) and Src--are up-regulated. Blockade of ß1 by the antibody AIIB2 abrogates this up-regulation and functionally achieves significant growth inhibition of L and LT resistant cells in 3D, without dramatically affecting the parental cells. SiRNA against ß1 as well as pharmacologic inhibition of FAK achieve the same growth inhibitory effect. In contrast, trastuzumab-resistant cells, which retain high levels of phosphorylated EGFR/HER1, HER2, and HER3, are only modestly growth-inhibited by AIIB2. CONCLUSIONS: Our data suggest that HER2 activity, which is suppressed in resistance involving L but not T alone, dictates whether ß1 mediates an alternative pathway driving resistance. Our findings justify clinical studies investigating the inhibition of ß1 or its downstream signaling moieties as strategies to overcome acquired L and LT resistance.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Integrina beta1/metabolismo , Quinazolinas/farmacologia , Anticorpos/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Humanos , Integrina beta1/genética , Integrina beta1/imunologia , Lapatinib , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Trastuzumab , Regulação para Cima , Quinases da Família src/metabolismo
9.
Int J Radiat Oncol Biol Phys ; 111(3): 638-642, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34153380

RESUMO

PURPOSE: Achieving competency as educators is increasingly recognized as a critical part of residents' training in graduate medical education across specialties. In addition to teaching medical students, radiation oncology residents often play a vital role in peer and interprofessional education. We conducted a survey to identify the needs of radiation oncology residents for developing skills in teaching. METHODS AND MATERIALS: An anonymous, web-based survey was developed and distributed to resident physicians at US radiation oncology programs. Analyses describe respondent demographics, experiences with teaching, and interest in various aspects of a formal "residents-as-teachers" curriculum. RESULTS: There were 171 completed survey responses (27.5% response rate). A total of 146 residents (85.4%) reported receiving no formal training in teaching before residency, and 121 (70.8%) reported no formal training during residency. Residents who had formal training in teaching were significantly more likely to be "quite" or "extremely" confident about teaching compared with residents who had no prior formal training (76.0% vs 51.4%; P = .022). Residents most commonly taught other residents and medical students (163 [95.3%] and 160 [93.6%] respondents, respectively). The most common settings for teaching were one-on-one teaching (164 respondents [95.9%]), small-group lectures (135 respondents [78.9%]), and intradepartmental lectures (136 respondents [79.5%]). In response to open-ended questions regarding desired teaching opportunities and domains for teaching development, many residents expressed a lack of confidence in teaching and were interested in improvement across many aspects of teaching. CONCLUSIONS: Radiation oncology residents are expected and desire to teach in a multitude of settings across a wide variety of audiences. However, a significant proportion of radiation oncology residents lack formal training and rarely receive feedback for their teaching skills. The results of this national survey support the development of a residents-as-teachers curriculum for radiation oncology residents that would address the needs for and significant interest in this area.


Assuntos
Internato e Residência , Radioterapia (Especialidade) , Currículo , Educação de Pós-Graduação em Medicina , Humanos , Avaliação das Necessidades , Radioterapia (Especialidade)/educação , Inquéritos e Questionários
10.
J Exp Med ; 218(5)2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33822843

RESUMO

Triple-negative breast cancers (TNBCs) are associated with poor survival mediated by treatment resistance. TNBCs are fibrotic, yet little is known regarding how the extracellular matrix (ECM) evolves following therapy and whether it impacts treatment response. Analysis revealed that while primary untreated TNBCs are surrounded by a rigid stromal microenvironment, chemotherapy-resistant residual tumors inhabit a softer niche. TNBC organoid cultures and xenograft studies showed that organoids interacting with soft ECM exhibit striking resistance to chemotherapy, ionizing radiation, and death receptor ligand TRAIL. A stiff ECM enhanced proapoptotic JNK activity to sensitize cells to treatment, whereas a soft ECM promoted treatment resistance by elevating NF-κB activity and compromising JNK activity. Treatment-resistant residual TNBCs residing within soft stroma had elevated activated NF-κB levels, and disengaging NF-κB activity sensitized tumors in a soft matrix to therapy. Thus, the biophysical properties of the ECM modify treatment response, and agents that modulate stiffness-dependent NF-κB or JNK activity could enhance therapeutic efficacy in patients with TNBC.


Assuntos
Matriz Extracelular/metabolismo , NF-kappa B/metabolismo , Neoplasias de Mama Triplo Negativas/terapia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Quimiorradioterapia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/efeitos da radiação , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/efeitos da radiação , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Terapia Neoadjuvante , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos da radiação
11.
Breast Cancer Res Treat ; 122(1): 35-43, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19701706

RESUMO

Development of effective and durable breast cancer treatment strategies requires a mechanistic understanding of the influence of the microenvironment on response. Previous work has shown that cellular signaling pathways and cell morphology are dramatically influenced by three-dimensional (3D) cultures as opposed to traditional two-dimensional (2D) monolayers. Here, we compared 2D and 3D culture models to determine the impact of 3D architecture and extracellular matrix (ECM) on HER2 signaling and on the response of HER2-amplified breast cancer cell lines to the HER2-targeting agents Trastuzumab, Pertuzumab and Lapatinib. We show that the response of the HER2-amplified AU565, SKBR3 and HCC1569 cells to these anti-HER2 agents was highly dependent on whether the cells were cultured in 2D monolayer or 3D laminin-rich ECM gels. Inhibition of beta1 integrin, a major cell-ECM receptor subunit, significantly increased the sensitivity of the HER2-amplified breast cancer cell lines to the humanized monoclonal antibodies Trastuzumab and Pertuzumab when grown in a 3D environment. Finally, in the absence of inhibitors, 3D cultures had substantial impact on HER2 downstream signaling and induced a switch between PI3K-AKT- and RAS-MAPK-pathway activation in all cell lines studied, including cells lacking HER2 amplification and overexpression. Our data provide direct evidence that breast cancer cells are able to rapidly adapt to different environments and signaling cues by activating alternative pathways that regulate proliferation and cell survival, events that may play a significant role in the acquisition of resistance to targeted therapies.


Assuntos
Antineoplásicos/farmacologia , Técnicas de Cultura de Células , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/fisiologia , Transdução de Sinais/efeitos dos fármacos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Técnicas de Cultura de Células/instrumentação , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Ativação Enzimática/efeitos dos fármacos , Matriz Extracelular/fisiologia , Feminino , Géis , Humanos , Integrina beta1/fisiologia , Laminina/farmacologia , Lapatinib , Proteínas de Neoplasias/fisiologia , Quinazolinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Transdução de Sinais/genética , Trastuzumab
13.
Cancer Res ; 66(3): 1526-35, 2006 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16452209

RESUMO

Current therapeutic approaches to cancer are designed to target molecules that contribute to malignant behavior but leave normal tissues intact. beta(1) integrin is a candidate target well known for mediating cell-extracellular matrix (ECM) interactions that influence diverse cellular functions; its aberrant expression has been implicated in breast cancer progression and resistance to cytotoxic therapy. The addition of beta(1) integrin inhibitory agents to breast cancer cells at a single-cell stage in a laminin-rich ECM (three-dimensional lrECM) culture was shown to down-modulate beta(1) integrin signaling, resulting in malignant reversion. To investigate beta(1) integrin as a therapeutic target, we modified the three-dimensional lrECM protocol to approximate the clinical situation: before treatment, we allowed nonmalignant cells to form organized acinar structures and malignant cells to form tumor-like colonies. We then tested the ability of beta(1) integrin inhibitory antibody, AIIB2, to inhibit tumor cell growth in several breast cancer cell lines (T4-2, MDA-MB-231, BT474, SKBR3, and MCF-7) and one nonmalignant cell line (S-1). We show that beta(1) integrin inhibition resulted in a significant loss of cancer cells, associated with a decrease in proliferation and increase in apoptosis, and a global change in the composition of residual colonies. In contrast, nonmalignant cells that formed tissue-like structures remained resistant. Moreover, these cancer cell-specific antiproliferative and proapoptotic effects were confirmed in vivo with no discernible toxicity to animals. Our findings indicate that beta(1) integrin is a promising therapeutic target, and that the three-dimensional lrECM culture assay can be used to effectively distinguish malignant and normal tissue response to therapy.


Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Integrina beta1/metabolismo , Integrinas/antagonistas & inibidores , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/toxicidade , Anticorpos Monoclonais Humanizados , Apoptose/imunologia , Neoplasias da Mama/imunologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/imunologia , Feminino , Humanos , Integrina beta1/biossíntese , Integrina beta1/imunologia , Camundongos , Camundongos Nus , Fosforilação , Trastuzumab , Células Tumorais Cultivadas
14.
J Med Imaging (Bellingham) ; 5(1): 011014, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29296631

RESUMO

Although the role of cancer-activated stroma in malignant progression has been well investigated, the influence of an activated stroma in therapy response is not well understood. Using retrospective pilot cohorts, we previously observed that MRI detected stromal contrast enhancement was associated with proximity to the tumor and was predictive for relapse-free survival in patients with breast cancer receiving neoadjuvant chemotherapy. Here, to evaluate the association of stromal contrast enhancement to therapy, we applied an advanced tissue mapping technique to evaluate stromal enhancement patterns within 71 patients enrolled in the I-SPY 1 neoadjuvant breast cancer trial. We correlated MR stromal measurements with stromal protein levels involved in tumor progression processes. We found that stromal percent enhancement values decrease with distance from the tumor edge with the estimated mean change ranging [Formula: see text] to [Formula: see text] ([Formula: see text]) for time points T2 through T4. While not statistically significant, we found a decreasing trend in global stromal signal enhancement ratio values with the use of chemotherapy. There were no statistically significant differences between MR enhancement measurements and stromal protein levels. Findings from this study indicate that stromal features characterized by MRI are impacted by chemotherapy and may have predictive value in a larger study.

15.
J Natl Cancer Inst ; 110(4): 329-340, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29126306

RESUMO

Innovation and progress in radiation oncology depend on discovery and insights realized through research in radiation biology. Radiobiology research has led to fundamental scientific insights, from the discovery of stem/progenitor cells to the definition of signal transduction pathways activated by ionizing radiation that are now recognized as integral to the DNA damage response (DDR). Radiobiological discoveries are guiding clinical trials that test radiation therapy combined with inhibitors of the DDR kinases DNA-dependent protein kinase (DNA-PK), ataxia telangiectasia mutated (ATM), ataxia telangiectasia related (ATR), and immune or cell cycle checkpoint inhibitors. To maintain scientific and clinical relevance, the field of radiation biology must overcome challenges in research workforce, training, and funding. The National Cancer Institute convened a workshop to discuss the role of radiobiology research and radiation biologists in the future scientific enterprise. Here, we review the discussions of current radiation oncology research approaches and areas of scientific focus considered important for rapid progress in radiation sciences and the continued contribution of radiobiology to radiation oncology and the broader biomedical research community.


Assuntos
Pesquisa Biomédica , Neoplasias/radioterapia , Radiobiologia , Animais , Humanos , Transdução de Sinais
16.
Int J Radiat Biol ; 83(11-12): 753-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18058364

RESUMO

PURPOSE: Radiation therapy (RT) is a commonly used modality to treat human cancer. However, dose-limiting toxicity and resistance are major problems to improving treatment efficacy. Increasing evidence has pointed to the critical role of the tumor microenvironment and cell-extracellular matrix (ECM), specifically via beta1 integrins, in modifying response to therapy, including radiation. beta1 integrins have been implicated in several key processes in malignant progression and metastasis, and more recently in mediating resistance to cytotoxic chemotherapy and radiation. Evidence is mounting that beta1 integrins mediate essential survival signals post-IR, through both canonical and non-canonical integrin signaling pathways that make it a highly promising therapeutic target for several solid malignancies. CONCLUSIONS: In this mini-review article, we briefly summarize the most recent emerging findings concerning beta1 integrin and radiation survival that indicate the promise of beta1 integrin inhibitory agents as radiosensitizers.


Assuntos
Integrina beta1/fisiologia , Integrinas/antagonistas & inibidores , Neoplasias/radioterapia , Animais , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Sobrevivência Celular/efeitos da radiação , Matriz Extracelular/fisiologia , Matriz Extracelular/efeitos da radiação , Feminino , Humanos , Modelos Biológicos , Prognóstico , Tolerância a Radiação , Radiossensibilizantes/uso terapêutico , Radiobiologia , Transdução de Sinais/efeitos da radiação
19.
Cancer Immunol Res ; 3(5): 518-25, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25716473

RESUMO

Radiotherapy and chemotherapy following surgery are mainstays of treatment for breast cancer. Although multiple studies have recently revealed the significance of immune cells as mediators of chemotherapy response in breast cancer, less is known regarding roles for leukocytes as mediating outcomes following radiotherapy. To address this question, we utilized a syngeneic orthotopic murine model of mammary carcinogenesis to investigate if response to radiotherapy could be improved when select immune cells or immune-based pathways in the mammary microenvironment were inhibited. Treatment of mammary tumor-bearing mice with either a neutralizing mAb to colony-stimulating factor-1 (CSF-1) or a small-molecule inhibitor of the CSF-1 receptor kinase (i.e., PLX3397), resulting in efficient macrophage depletion, significantly delayed tumor regrowth following radiotherapy. Delayed tumor growth in this setting was associated with increased presence of CD8(+) T cells and reduced presence of CD4(+) T cells, the main source of the TH2 cytokine IL4 in mammary tumors. Selective depletion of CD4(+) T cells or neutralization of IL4 in combination with radiotherapy phenocopied results following macrophage depletion, whereas depletion of CD8(+) T cells abrogated improved response to radiotherapy following these therapies. Analogously, therapeutic neutralization of IL4 or IL13, or IL4 receptor alpha deficiency, in combination with the chemotherapy paclitaxel, resulted in slowed primary mammary tumor growth by CD8(+) T-cell-dependent mechanisms. These findings indicate that clinical responses to cytotoxic therapy in general can be improved by neutralizing dominant TH2-based programs driving protumorigenic and immune-suppressive pathways in mammary (breast) tumors to improve outcomes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Macrófagos/imunologia , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/radioterapia , Animais , Feminino , Interleucina-4/antagonistas & inibidores , Interleucina-4/imunologia , Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Fator Estimulador de Colônias de Macrófagos/imunologia , Camundongos , Resultado do Tratamento
20.
Int J Radiat Oncol Biol Phys ; 88(1): 11-7, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24246724

RESUMO

In early 2011, a dialogue was initiated within the Board of Directors (BOD) of the American Society for Radiation Oncology (ASTRO) regarding the future of the basic sciences of the specialty, primarily focused on the current state and potential future direction of basic research within radiation oncology. After consideration of the complexity of the issues involved and the precise nature of the undertaking, in August 2011, the BOD empanelled a Cancer Biology/Radiation Biology Task Force (TF). The TF was charged with developing an accurate snapshot of the current state of basic (preclinical) research in radiation oncology from the perspective of relevance to the modern clinical practice of radiation oncology as well as the education of our trainees and attending physicians in the biological sciences. The TF was further charged with making suggestions as to critical areas of biological basic research investigation that might be most likely to maintain and build further the scientific foundation and vitality of radiation oncology as an independent and vibrant medical specialty. It was not within the scope of service of the TF to consider the quality of ongoing research efforts within the broader radiation oncology space, to presume to consider their future potential, or to discourage in any way the investigators committed to areas of interest other than those targeted. The TF charge specifically precluded consideration of research issues related to technology, physics, or clinical investigations. This document represents an Executive Summary of the Task Force report.


Assuntos
Disciplinas das Ciências Biológicas , Previsões , Radioterapia (Especialidade) , Radiobiologia , Pesquisa , Comitês Consultivos/organização & administração , Disciplinas das Ciências Biológicas/educação , Disciplinas das Ciências Biológicas/normas , Disciplinas das Ciências Biológicas/tendências , Biomarcadores/análise , Hipóxia Celular , Currículo , Reparo do DNA , Genômica , Imagem Molecular , Neoplasias/metabolismo , Neoplasias/terapia , Radioterapia (Especialidade)/educação , Radioterapia (Especialidade)/normas , Radioterapia (Especialidade)/tendências , Protetores contra Radiação/farmacologia , Radiossensibilizantes/farmacologia , Radiobiologia/educação , Radiobiologia/normas , Radiobiologia/tendências , Pesquisa/educação , Pesquisa/normas , Pesquisa/tendências , Apoio à Pesquisa como Assunto , Transdução de Sinais , Sociedades Médicas , Células-Tronco/fisiologia , Pesquisa Translacional Biomédica , Microambiente Tumoral , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa