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2.
Int J Radiat Oncol Biol Phys ; 113(3): 490, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35777389

Subject(s)
Risk Factors , Humans
4.
Cancer ; 128(2): 344-352, 2022 01 15.
Article in English | MEDLINE | ID: mdl-34550601

ABSTRACT

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.


Subject(s)
Mental Health , Neoplasms , Adult , Cohort Studies , Electronic Health Records , Humans , Neoplasms/diagnosis , Retrospective Studies
5.
Int J Radiat Oncol Biol Phys ; 111(3): 638-642, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34153380

ABSTRACT

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.


Subject(s)
Internship and Residency , Radiation Oncology , Curriculum , Education, Medical, Graduate , Humans , Needs Assessment , Radiation Oncology/education , Surveys and Questionnaires
6.
J Exp Med ; 218(5)2021 05 03.
Article in English | MEDLINE | ID: mdl-33822843

ABSTRACT

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.


Subject(s)
Extracellular Matrix/metabolism , NF-kappa B/metabolism , Triple Negative Breast Neoplasms/therapy , Xenograft Model Antitumor Assays/methods , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/radiation effects , Chemoradiotherapy , Enzyme Activation/drug effects , Enzyme Activation/radiation effects , Extracellular Matrix/drug effects , Extracellular Matrix/radiation effects , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Mice, Inbred NOD , Mice, Nude , Mice, SCID , Neoadjuvant Therapy , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Tumor Microenvironment/drug effects , Tumor Microenvironment/radiation effects
7.
J Med Imaging (Bellingham) ; 5(1): 011014, 2018 01.
Article in English | MEDLINE | ID: mdl-29296631

ABSTRACT

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.

8.
J Natl Cancer Inst ; 110(4): 329-340, 2018 04 01.
Article in English | MEDLINE | ID: mdl-29126306

ABSTRACT

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.


Subject(s)
Biomedical Research , Neoplasms/radiotherapy , Radiobiology , Animals , Humans , Signal Transduction
9.
Proc Natl Acad Sci U S A ; 114(41): E8685-E8694, 2017 10 10.
Article in English | MEDLINE | ID: mdl-28973887

ABSTRACT

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.


Subject(s)
Breast Neoplasms/secondary , Drug Resistance, Neoplasm , Glioblastoma/secondary , Integrin beta1/metabolism , Proto-Oncogene Proteins c-met/metabolism , Angiogenesis Inhibitors/pharmacology , Animals , Apoptosis/drug effects , Bevacizumab/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Adhesion/drug effects , Cell Movement/drug effects , Female , Fibronectins/metabolism , Glioblastoma/drug therapy , Glioblastoma/metabolism , Humans , Integrin beta1/genetics , Mice , Neoplasm Invasiveness , Phosphorylation/drug effects , Proto-Oncogene Proteins c-met/genetics , Signal Transduction/drug effects , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
10.
Breast Cancer Res Treat ; 155(3): 431-40, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26860947

ABSTRACT

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.


Subject(s)
Breast Neoplasms/drug therapy , Doxycycline/administration & dosage , Integrin beta1/genetics , Receptor, ErbB-2/genetics , Receptor, ErbB-3/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Resistance, Neoplasm/genetics , Female , Humans , Integrin beta1/drug effects , Molecular Targeted Therapy , Phosphatidylinositol 3-Kinases/genetics , RNA, Small Interfering/genetics , RNA, Small Interfering/therapeutic use , Receptor, ErbB-2/antagonists & inhibitors , Receptor, ErbB-3/antagonists & inhibitors , Signal Transduction/drug effects , Treatment Outcome
11.
Oncology (Williston Park) ; 29(6): 446-58, 460-1, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26089220

ABSTRACT

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.


Subject(s)
Breast Neoplasms/therapy , Carcinoma, Intraductal, Noninfiltrating/therapy , Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Carcinoma, Lobular/pathology , Carcinoma, Lobular/therapy , Female , Humans , Magnetic Resonance Imaging , Mammography , Mastectomy , Mastectomy, Segmental , Neoplasm Invasiveness , Radiotherapy Dosage , Radiotherapy, Adjuvant , Sentinel Lymph Node Biopsy , Tamoxifen/therapeutic use
12.
Cancer Immunol Res ; 3(5): 518-25, 2015 May.
Article in English | MEDLINE | ID: mdl-25716473

ABSTRACT

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.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Macrophages/immunology , Mammary Neoplasms, Experimental/immunology , Mammary Neoplasms, Experimental/radiotherapy , Animals , Female , Interleukin-4/antagonists & inhibitors , Interleukin-4/immunology , Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Macrophage Colony-Stimulating Factor/immunology , Mice , Treatment Outcome
13.
Oncology (Williston Park) ; 28(2): 157-64, C3, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24701707

ABSTRACT

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.


Subject(s)
Breast Neoplasms/therapy , Neoplasm Recurrence, Local/therapy , Salvage Therapy/methods , Adult , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Combined Modality Therapy , Female , Humans , Middle Aged , Neoplasm Recurrence, Local/pathology , Practice Guidelines as Topic
14.
Int J Radiat Oncol Biol Phys ; 88(1): 11-7, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24246724

ABSTRACT

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.


Subject(s)
Biological Science Disciplines , Forecasting , Radiation Oncology , Radiobiology , Research , Advisory Committees/organization & administration , Biological Science Disciplines/education , Biological Science Disciplines/standards , Biological Science Disciplines/trends , Biomarkers/analysis , Cell Hypoxia , Curriculum , DNA Repair , Genomics , Molecular Imaging , Neoplasms/metabolism , Neoplasms/therapy , Radiation Oncology/education , Radiation Oncology/standards , Radiation Oncology/trends , Radiation-Protective Agents/pharmacology , Radiation-Sensitizing Agents/pharmacology , Radiobiology/education , Radiobiology/standards , Radiobiology/trends , Research/education , Research/standards , Research/trends , Research Support as Topic , Signal Transduction , Societies, Medical , Stem Cells/physiology , Translational Research, Biomedical , Tumor Microenvironment , United States
15.
Ann Surg Oncol ; 20(9): 2873-80, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23812769

ABSTRACT

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.


Subject(s)
Brachytherapy/economics , Breast Neoplasms/economics , Cost-Benefit Analysis , Markov Chains , Neoplasm Recurrence, Local/economics , Radiotherapy, Adjuvant/economics , Brachytherapy/mortality , Breast Neoplasms/mortality , Breast Neoplasms/radiotherapy , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Intraoperative Care , Lymphatic Metastasis , Middle Aged , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Staging , Prognosis , Quality of Life , Radiotherapy, Adjuvant/mortality , Survival Rate
16.
Breast Cancer Res ; 15(4): R60, 2013.
Article in English | MEDLINE | ID: mdl-23883667

ABSTRACT

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.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Integrin beta1/metabolism , NF-kappa B/metabolism , Signal Transduction , Animals , Apoptosis/genetics , Apoptosis/radiation effects , Breast Neoplasms/genetics , Breast Neoplasms/radiotherapy , Carcinoma, Intraductal, Noninfiltrating/metabolism , Carcinoma, Intraductal, Noninfiltrating/pathology , Carcinoma, Intraductal, Noninfiltrating/radiotherapy , Cell Line, Tumor , Disease Models, Animal , Enzyme Activation , Female , Heterografts , Humans , Integrin beta1/genetics , Mice , Neoplasm Invasiveness , Neoplasm Recurrence, Local , Phosphorylation , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Radiation, Ionizing , Spheroids, Cellular , Tumor Cells, Cultured , Up-Regulation
17.
Cancer Res ; 73(10): 3145-54, 2013 May 15.
Article in English | MEDLINE | ID: mdl-23644530

ABSTRACT

Antiangiogenic therapies like bevacizumab offer promise for cancer treatment, but acquired resistance, which often includes an aggressive mesenchymal phenotype, can limit the use of these agents. Upregulation of ß1 integrin (ITGB1) occurs in some bevacizumab-resistant glioblastomas (BRG) whereby, mediating tumor-microenvironment interactions, we hypothesized that it may mediate a mesenchymal-type resistance to antiangiogenic therapy. Immunostaining analyses of ß1 integrin and its downstream effector kinase FAK revealed upregulation in 75% and 86% of BRGs, respectively, compared with pretreatment paired specimens. Furthermore, flow cytometry revealed eight-fold more ß1 integrin in primary BRG cells compared with cells from bevacizumab-naïve glioblastomas (BNG). Fluorescence recovery after photobleaching of cells engineered to express a ß1-GFP fusion protein indicated that the mobile ß1 integrin fraction was doubled, and half-life of ß1 integrin turnover in focal adhesions was reduced markedly in BRG cells compared with bevacizumab-responsive glioblastoma multiforme cells. Hypoxia, which was increased with acquisition of bevacizumab resistance, was associated with increased ß1 integrin expression in cultured BNG cells. BRGs displayed an aggressive mesenchymal-like phenotype in vitro. We found that growth of BRG xenograft tumors was attenuated by the ß1 antibody, OS2966, allowing a 20-fold dose reduction of bevacizumab per cycle in this model. Intracranial delivery of OS2966 through osmotic pumps over 28 days increased tumor cell apoptosis, decreased tumor cell invasiveness, and blunted the mesenchymal morphology of tumor cells. We concluded that ß1 integrin upregulation in BRGs likely reflects an onset of hypoxia caused by antiangiogenic therapy, and that ß1 inhibition is well tolerated in vivo as a tractable strategy to disrupt resistance to this therapy.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Brain Neoplasms/drug therapy , Glioblastoma/drug therapy , Integrin beta1/physiology , Animals , Bevacizumab , Brain Neoplasms/pathology , Cell Hypoxia , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Synergism , Female , Glioblastoma/pathology , Humans , Mice , Spheroids, Cellular/drug effects , Tumor Microenvironment/drug effects
18.
PLoS One ; 8(5): e61969, 2013.
Article in English | MEDLINE | ID: mdl-23667451

ABSTRACT

RATIONALE AND OBJECTIVES: Normal-appearing stromal tissues surrounding breast tumors can harbor abnormalities that lead to increased risk of local recurrence. The objective of this study was to develop a new imaging methodology to characterize the signal patterns of stromal tissue and to investigate their association with recurrence-free survival following neoadjuvant chemotherapy. MATERIALS AND METHODS: Fifty patients with locally-advanced breast cancer were imaged with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) before (V1) and after one cycle (V2) of adriamycin-cytoxan therapy. Contrast enhancement in normal-appearing stroma around the tumor was characterized by the mean percent enhancement (PE) and mean signal enhancement ratio (SER) in distance bands of 5 mm from the tumor edge. Global PE and SER were calculated by averaging all stromal bands 5 to 40 mm from tumor. Proximity-dependent PE and SER were analyzed using a linear mixed effects model and Cox proportional hazards model for recurrence-free survival. RESULTS: The mixed effects model displayed a decreasing radial trend in PE at both V1 and V2. An increasing trend was less pronounced in SER. Survival analysis showed that the hazard ratio estimates for each unit decrease in global SER was statistically significant at V1 [estimated hazard ratio = 0.058, 95% Wald CI (0.003, 1.01), likelihood ratio p = 0.03]; but was not so for V2. CONCLUSIONS: These findings show that stromal tissue outside the tumor can be quantitatively characterized by DCE-MRI, and suggest that stromal enhancement measurements may be further developed for use as a potential predictor of recurrence/disease-free survival following therapy.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Image Enhancement/methods , Magnetic Resonance Imaging/methods , Neoadjuvant Therapy , Adult , Aged , Disease-Free Survival , Female , Humans , Middle Aged , Neoplasm Staging , Reproducibility of Results , Signal-To-Noise Ratio
19.
Cancer Res ; 73(12): 3737-48, 2013 Jun 15.
Article in English | MEDLINE | ID: mdl-23576567

ABSTRACT

ß1-integrin induction enhances breast cancer cell survival after exposure to ionizing radiation (IR), but the mechanisms of this effect remain unclear. Although NF-κB initiates prosurvival signaling pathways post-IR, the molecular function of NF-κB with other key elements in radioresistance, particularly with respect to extracellular matrix-induced signaling, is not known. We discovered a typical NF-κB-binding site in the ß1-integrin promoter region, indicating a possible regulatory role for NF-κB. Using three-dimensional laminin-rich extracellular matrix (3D lrECM) culture, we show that NF-κB is required for ß1-integrin transactivation in T4-2 breast cancer cells post-IR. Inhibition of NF-κB reduced clonogenic survival and induced apoptosis and cytostasis in formed tumor colonies. In addition, T4-2 tumors with inhibition of NF-κB activity exhibit decreased growth in athymic mice, which was further reduced by IR with downregulated ß1-integrin expression. Direct interactions between ß1-integrin and NF-κB p65 were induced in nonmalignant breast epithelial cells, but not in malignant cells, indicating context-specific regulation. As ß1-integrin also activates NF-κB, our findings reveal a novel forward feedback pathway that could be targeted to enhance therapy.


Subject(s)
Breast Neoplasms/metabolism , Cell Culture Techniques/methods , Integrin beta1/metabolism , NF-kappa B/metabolism , Animals , Binding Sites/genetics , Blotting, Western , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , Cell Survival/radiation effects , Extracellular Matrix/metabolism , Female , Humans , Integrin beta1/genetics , Mice , Mice, Nude , Microscopy, Confocal , NF-kappa B/antagonists & inhibitors , Phenylenediamines/pharmacology , Promoter Regions, Genetic/genetics , Protein Binding/drug effects , Protein Binding/radiation effects , Radiation Tolerance/genetics , Radiation, Ionizing , Transcription Factor RelA/antagonists & inhibitors , Transcription Factor RelA/metabolism , Tumor Burden/drug effects , Tumor Burden/radiation effects , Xenograft Model Antitumor Assays
20.
Integr Biol (Camb) ; 5(4): 681-91, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23407655

ABSTRACT

Three-dimensional (3D) tissue culture provides a physiologically relevant microenvironment for distinguishing malignant from non-malignant breast cell phenotypes. 3D culture assays can also be used to test novel cancer therapies and predict a differential response to radiation between normal and malignant cells in vivo. However, biological measurements in such complex models are difficult to quantify and current approaches do not allow for in-depth multifaceted assessment of individual colonies or unique sub-populations within the entire culture. This is in part due to the limitations of imaging at a range of depths in 3D culture resulting from optical aberrations and intensity attenuation. Here, we address these limitations by combining sample smearing techniques with high-throughput 2D imaging algorithms to accurately and rapidly quantify imaging features acquired from 3D cultures. Multiple high resolution imaging features especially designed to characterize 3D cultures show that non-malignant human breast cells surviving large doses of ionizing radiation acquire a "swelled acinar" phenotype with fewer and larger nuclei, loss of cell connectivity and diffused basement membrane. When integrating these imaging features into hierarchical clustering classification, we could also identify subpopulations of phenotypes from individual human tumor colonies treated with ionizing radiation or/and integrin inhibitors. Such tools have therefore the potential to further characterize cell culture populations after cancer treatment and identify novel phenotypes of resistance.


Subject(s)
Algorithms , Artificial Intelligence , Breast Neoplasms/pathology , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Microscopy, Fluorescence/methods , Pattern Recognition, Automated/methods , Breast Neoplasms/radiotherapy , Cell Line, Tumor , Female , Humans , Reproducibility of Results , Sensitivity and Specificity
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