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- Aguilar, Helena, et al.
(författare)
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VAV3 mediates resistance to breast cancer endocrine therapy
- 2014
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Ingår i: Breast Cancer Research. - : BioMed Central. - 1465-5411 .- 1465-542X. ; 16:3, s. R53-
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Endocrine therapies targeting cell proliferation and survival mediated by estrogen receptor alpha (ERalpha) are among the most effective systemic treatments for ERalpha-positive breast cancer. However, most tumors initially responsive to these therapies acquire resistance through mechanisms that involve ERalpha transcriptional regulatory plasticity. Here, we identify VAV3 as a critical component in this process.METHODS: A cell-based chemical compound screen was carried out to identify therapeutic strategies against resistance to endocrine therapy. Binding to ERalpha was evaluated by molecular docking analyses, an agonist fluoligand assay, and short-hairpin (sh) RNA-mediated protein depletion. Microarray analyses were performed to identify altered gene expression. Western blot of signaling and proliferation markers and shRNA-mediated protein depletion in viability and clonogenic assays were performed to delineate the role of VAV3. Genetic variation in VAV3 was assessed for association with the response to tamoxifen. Immunohistochemical analyses of VAV3 were carried out to determine the association with therapy response and different tumor markers. An analysis of gene expression association with drug sensitivity was carried out to identify a potential therapeutic approach based on differential VAV3 expression.RESULTS: The compound YC-1 was found to comparatively reduce the viability of cell models of acquired resistance. This effect was probably not due to activation of its canonical target (soluble guanylyl cyclase) but instead a result of binding to ERalpha. VAV3 was selectively reduced upon exposure to YC-1 or ERalpha depletion and, accordingly, VAV3 depletion comparatively reduced the viability of cell models of acquired resistance. In the clinical scenario, germline variation in VAV3 was associated with response to tamoxifen in Japanese breast cancer patients (rs10494071 combined P value = 8.4 x 10-4). The allele association combined with gene expression analyses indicated that low VAV3 expression predicts better clinical outcome. Conversely, high nuclear VAV3 expression in tumor cells was associated with poorer endocrine therapy response. Based on VAV3 expression levels and the response to erlotinib in cancer cell lines, targeting EGFR signaling may be a promising therapeutic strategy.CONCLUSIONS: This study proposes VAV3 as a biomarker and rationale signaling target to prevent and/or overcome resistance to endocrine therapy in breast cancer.
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| 2. |
- Hernandez, Luiza I., et al.
(författare)
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Discovery and Proof-of-Concept Study of Nuclease Activity as a Novel Biomarker for Breast Cancer Tumors
- 2021
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Ingår i: Cancers. - : MDPI. - 2072-6694. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- Simple Summary A diagnostic biomarker for the detection of breast cancer remains an unmet clinical need despite decades of intensive research efforts. Herein, we describe, for the first time, the use of nuclease activity as a biomarker to discriminate between healthy and cancer biopsy samples. We have identified a panel of three nucleic acid probes able to target nucleases derived from breast cancer tumors with high sensitivity and specificity. These results are in good agreement with histopathological analysis as the diagnostic gold standard. Moreover, these findings support nuclease activity as a potential adjacent diagnostic tool and shed light on the use of nuclease activity as a detection biomarker in breast cancer. Breast cancer is one of the most common pathologies diagnosed in the clinical practice. Despite major advancements in diagnostic approaches, there is no widely accepted biomarker in the clinical practice that can diagnose breast malignancy. Confirmatory diagnosis still relies on the pathological assessment of tissue biopsies by expert pathologists. Thus, there is an unmet need for new types of biomarkers and novel platform technologies that can be easily and robustly integrated into the clinic and that can assist pathologists. Herein, we show that nuclease activity associated to malignant tumors can be used as a novel biomarker in breast cancer, which can be detected via specific degradation of nucleic acid probes. In this study we have identified a set of three chemically modified nucleic acid probes that can diagnose malignancy in biopsy samples with high accuracy (89%), sensitivity (82%) and specificity (94%). This work represents a breakthrough for the potential clinical use of nuclease activity as biomarker, which can be detected via nucleic acids probes, for the clinical diagnosis of malignancy in breast tissue biopsies. This platform technology could be readily implemented into the clinic as adjunct to histopathological diagnostic.
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| 3. |
- Hiensch, Anouk E, et al.
(författare)
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Design of a multinational randomized controlled trial to assess the effects of structured and individualized exercise in patients with metastatic breast cancer on fatigue and quality of life : the EFFECT study.
- 2022
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Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 23:1, s. 610-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Many patients with metastatic breast cancer experience cancer- and treatment-related side effects that impair activities of daily living and negatively affect the quality of life. There is a need for interventions that improve quality of life by alleviating fatigue and other side effects during palliative cancer treatment. Beneficial effects of exercise have been observed in the curative setting, but, to date, comparable evidence in patients with metastatic breast cancer is lacking. The aim of this study is to assess the effects of a structured and individualized 9-month exercise intervention in patients with metastatic breast cancer on quality of life, fatigue, and other cancer- and treatment-related side effects.METHODS: The EFFECT study is a multinational, randomized controlled trial including 350 patients with metastatic breast cancer. Participants are randomly allocated (1:1) to an exercise or control group. The exercise group participates in a 9-month multimodal exercise program, starting with a 6-month period where participants exercise twice a week under the supervision of an exercise professional. After completing this 6-month period, one supervised session is replaced by one unsupervised session for 3 months. In addition, participants are instructed to be physically active for ≥30 min/day on all remaining days of the week, while being supported by an activity tracker and exercise app. Participants allocated to the control group receive standard medical care, general written physical activity advice, and an activity tracker, but no structured exercise program. The primary outcomes are quality of life (EORTC QLQ-C30, summary score) and fatigue (EORTC QLQ-FA12), assessed at baseline, 3, 6 (primary endpoint), and 9 months post-baseline. Secondary outcomes include physical fitness, physical performance, physical activity, anxiety, depression, pain, sleep problems, anthropometric data, body composition, and blood markers. Exploratory outcomes include quality of working life, muscle thickness, urinary incontinence, disease progression, and survival. Additionally, the cost-effectiveness of the exercise program is assessed. Adherence and safety are monitored throughout the intervention period.DISCUSSION: This large randomized controlled trial will provide evidence regarding the (cost-) effectiveness of exercise during treatment of metastatic breast cancer. If proven (cost-)effective, exercise should be offered to patients with metastatic breast cancer as part of standard care.TRIAL REGISTRATION: ClinicalTrials.gov NCT04120298 . Registered on October 9, 2019.
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| 4. |
- Maxwell, Christopher A., et al.
(författare)
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Interplay between BRCA1 and RHAMM Regulates Epithelial Apicobasal Polarization and May Influence Risk of Breast Cancer
- 2011
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Ingår i: PLoS Biology. - : Public Library of Science (PLoS). - 1545-7885 .- 1544-9173. ; 9:11
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Tidskriftsartikel (refereegranskat)abstract
- Differentiated mammary epithelium shows apicobasal polarity, and loss of tissue organization is an early hallmark of breast carcinogenesis. In BRCA1 mutation carriers, accumulation of stem and progenitor cells in normal breast tissue and increased risk of developing tumors of basal-like type suggest that BRCA1 regulates stem/progenitor cell proliferation and differentiation. However, the function of BRCA1 in this process and its link to carcinogenesis remain unknown. Here we depict a molecular mechanism involving BRCA1 and RHAMM that regulates apicobasal polarity and, when perturbed, may increase risk of breast cancer. Starting from complementary genetic analyses across families and populations, we identified common genetic variation at the low-penetrance susceptibility HMMR locus (encoding for RHAMM) that modifies breast cancer risk among BRCA1, but probably not BRCA2, mutation carriers: n = 7,584, weighted hazard ratio ((w)HR) = 1.09 (95% CI 1.02-1.16), p(trend) = 0.017; and n = 3,965, (w)HR = 1.04 (95% CI 0.94-1.16), p(trend) = 0.43; respectively. Subsequently, studies of MCF10A apicobasal polarization revealed a central role for BRCA1 and RHAMM, together with AURKA and TPX2, in essential reorganization of microtubules. Mechanistically, reorganization is facilitated by BRCA1 and impaired by AURKA, which is regulated by negative feedback involving RHAMM and TPX2. Taken together, our data provide fundamental insight into apicobasal polarization through BRCA1 function, which may explain the expanded cell subsets and characteristic tumor type accompanying BRCA1 mutation, while also linking this process to sporadic breast cancer through perturbation of HMMR/RHAMM.
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