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1.
Int J Cancer ; 154(4): 712-722, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37984064

RESUMO

Probably, the most important factor for the survival of a melanoma patient is early detection and precise diagnosis. Although in most cases these tasks are readily carried out by pathologists and dermatologists, there are still difficult cases in which no consensus among experts is achieved. To deal with such cases, new methodologies are required. Following this motivation, we explore here the use of lipid imaging mass spectrometry as a complementary tool for the aid in the diagnosis. Thus, 53 samples (15 nevus, 24 primary melanomas, and 14 metastasis) were explored with the aid of a mass spectrometer, using negative polarity. The rich lipid fingerprint obtained from the samples allowed us to set up an artificial intelligence-based classification model that achieved 100% of specificity and precision both in training and validation data sets. A deeper analysis of the image data shows that the technique reports important information on the tumor microenvironment that may give invaluable insights in the prognosis of the lesion, with the correct interpretation.


Assuntos
Melanoma , Nevo , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Inteligência Artificial , Nevo/diagnóstico , Nevo/patologia , Lipídeos , Microambiente Tumoral
2.
Target Oncol ; 18(4): 559-570, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37369815

RESUMO

BACKGROUND: Immuno-oncology combinations have achieved survival benefits in patients with metastatic renal cell carcinoma (mRCC). OBJECTIVE: The ARON-1 study (NCT05287464) was designed to globally collect real-world data on the use of immuno-combinations as first-line therapy for mRCC patients. PATIENTS AND METHODS: Patients aged ≥ 18 years with a cytologically and/or histologically confirmed diagnosis of mRCC treated with first-line immuno-combination therapies were retrospectively included from 47 International Institutions from 16 countries. Patients were assessed for overall survival (OS), progression-free survival (PFS), and overall clinical benefit (OCB). RESULTS: A total of 729 patients were included; tumor histology was clear-cell RCC in 86% of cases; 313 patients received dual immuno-oncology (IO + IO) therapy while 416 were treated with IO-tyrosine kinase inhibitor (IO + TKI) combinations. In the overall study population, the median OS and PFS were 36.5 and 15.0 months, respectively. The median OS was longer with IO+TKI compared with IO+IO therapy in the 616 patients with intermediate/poor International mRCC Database Consortium (IMDC) risk criteria (55.7 vs 29.7 months; p = 0.045). OCB was 84% for IO+TKI and 72% for IO + IO combination (p < 0.001). CONCLUSIONS: Our study may suggest that immuno-oncology combinations are effective as first-line therapy in the mRCC real-world context, showing outcome differences between IO + IO and IO + TKI combinations in mRCC subpopulations. CLINICAL TRIAL REGISTRATION: NCT05287464.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Estudos Retrospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Intervalo Livre de Progressão
3.
Cancer Immunol Immunother ; 72(9): 2961-2970, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37248424

RESUMO

BACKGROUND: The advent of immune-checkpoint inhibitors has challenged previous treatment paradigms for advanced urothelial carcinoma (UC) in the post-platinum setting as well as in the first-line setting for cisplatin-ineligible patients. In this study, we investigated the effectiveness of pembrolizumab as first-line treatment for cisplatin-ineligible UC. METHODS: Data from patients aged ≥ 18 years with cisplatin-ineligible UC and receiving first-line pembrolizumab from January 1st 2017 to September 1st 2022 were collected. Cisplatin ineligibility was defined according to the Galsky criteria. Thirty-three Institutions from 18 countries were involved in the ARON-2 study. RESULTS: Our analysis included 162 patients. The median follow-up time was 18.9 months (95%CI 15.3-76.9). In the overall study population, the median OS was 15.8 months (95%CI 11.3-32.4). The median OS was significantly longer in males versus females while no statistically significant differences were observed between patients aged < 65y versus ≥ 65y and between smokers and non-smokers. According to Recist 1.1 criteria, 26 patients (16%) experienced CR, 32 (20%) PR, 39 (24%) SD and 55 (34%) PD. CONCLUSIONS: Our data confirm the role of pembrolizumab as first-line therapy for cisplatin-unfit patients. Further studies investigating the biological and immunological characteristics of UC patients are warranted in order to optimize the outcome of patients receiving immunotherapy in this setting.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Masculino , Feminino , Humanos , Carcinoma de Células de Transição/patologia , Cisplatino/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Anticorpos Monoclonais Humanizados/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica
4.
Clin Genitourin Cancer ; 21(5): e309-e319.e1, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37062658

RESUMO

BACKGROUND: Obesity has been associated with improved response to immunotherapy in cancer patients. We investigated the role of body mass index (BMI) in patients from the ARON-1 study (NCT05287464) treated by dual immuno-oncology agents (IO+IO) or a combination of immuno-oncology drug and a tyrosine kinase inhibitors (TKI) as first-line therapy for metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS: Medical records of patients with documented mRCC treated by immuno-oncology combinations were reviewed at 47 institutions from 16 countries. Patients were assessed for overall survival (OS), progression-free survival (OS), and overall clinical benefit (OCB), defined as the sum of the rate of partial/complete responses and stable disease. Univariate and multivariate analyses were used to explore the association of variables of interest with survival. RESULTS: A total of 675 patients were included; BMI was >25 kg/m2 in 345 patients (51%) and was associated with improved OS (55.7 vs. 28.4 months, P < .001). The OCB of patients with BMI >25 kg/m2 versus those with BMI ≤25 kg/m2 was significantly higher only in patients with nonclear cell histology (81% vs. 65%, P = .011), and patients with liver metastases (76% vs. 58%, P = .007), Neutrophil to lymphocyte ratio >4 (77% vs 62%, P = .022) or treated by nivolumab plus ipilimumab (77% vs. 64%, P = .044). In the BMI ≤25 kg/m2 subgroup, significant differences were found between patients with NLR >4 versus ≤4 (62% vs. 82%, P = .002) and patients treated by IO+IO versus IO+TKIs combinations (64% vs. 83%, P = .002). CONCLUSION: Our study suggests that the prognostic significance and the association of BMI with treatment outcome varies across clinico-pathological mRCC subgroups.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Índice de Massa Corporal , Prognóstico , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos
5.
Cancers (Basel) ; 14(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36077734

RESUMO

Precise prognosis is crucial for selection of adjuvant therapy in breast cancer. Molecular subtyping is increasingly used to complement immunohistochemical and pathological classification and to predict recurrence. This study compares both outcomes in a clinical setting. Molecular subtyping (MammaPrint®, TargetPrint®, and BluePrint®) and pathological classification data were compared in a cohort of 143 breast cancer patients. High risk clinical factors were defined by a value of the proliferation factor Ki67 equal or higher than 14% and/or high histological grade. The results from molecular classification were considered as reference. Core needle biopsies were found to be comparable to surgery samples for molecular classification. Discrepancies were found between molecular and pathological subtyping of the samples, including misclassification of HER2-positive tumors and the identification of a significant percentage of genomic high risk T1N0 tumors. In addition, 20% of clinical low-risk tumors showed genomic high risk, while clinical high-risk samples included 42% of cases with genomic low risk. According to pathological subtyping, a considerable number of breast cancer patients would not receive the appropriate systemic therapy. Our findings support the need to determine the molecular subtype of invasive breast tumors to improve breast cancer management.

6.
Target Oncol ; 17(5): 571-581, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35947324

RESUMO

BACKGROUND: Drug-drug interactions are a major concern in oncology and may potentially affect the outcome of patients with cancer. OBJECTIVE: In this study, we aimed to determine whether the concomitant use of statins, metformin, or proton pump inhibitors affects survival in patients with metastatic renal cell carcinoma treated with first-line combination therapies. METHODS: Medical records of patients with documented metastatic renal cell carcinoma between January 2016 and November 2021 were reviewed at 17 participating centers. This research was conducted in ten institutions, including both referral centers and local hospitals. Patients were assessed for overall survival, progression-free survival, and overall clinical benefit. Univariate and multivariate analyses were conducted to explore the association of variables of interest with overall survival and progression-free survival. RESULTS: A total of 304 patients receiving dual immunotherapy (51%) or immunotherapy/vascular endothelial growth factor-tyrosine kinase inhibitor (49%) combinations were eligible for inclusion in this retrospective study. Statin use was a significant prognostic factor for longer overall survival in a univariate analysis (hazard ratio 0.48, 95% confidence interval 0.26-0.87; p = 0.016) and a multivariate analysis (hazard ratio 0.48, 95% confidence interval 0.31-0.74; p < 0.001) and was significantly associated with an overall clinical benefit (83% in statin users vs 71% in non-users; p = 0.045). Otherwise, the use of metformin or proton pump inhibitors did not affect the outcome of these patients. CONCLUSIONS: Our study suggests a prognostic impact of statin use in patients receiving first-line immuno-oncology combinations. The mechanism of this interaction warrants further elucidation.


Assuntos
Carcinoma de Células Renais , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Renais , Metformina , Inibidores da Angiogênese/uso terapêutico , Carcinoma de Células Renais/patologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Renais/patologia , Metformina/farmacologia , Metformina/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores da Bomba de Prótons/farmacologia , Inibidores da Bomba de Prótons/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular
7.
Crit Rev Oncol Hematol ; 176: 103731, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35718065

RESUMO

Statins are commonly prescribed to reduce plasma cholesterol levels and risk of cardiovascular events and mortality. Statin exposure may have cancer-preventive properties in some solid tumors, including Renal Cell Carcinoma (RCC). Emerging evidences show that statins can inhibit RCC cell growth by inducing cell cycle arrest and apoptosis in a dose- and time-dependent manner. In addition, statins inhibit the phosphorylation of AKT, mammalian target of rapamycin (mTOR), and ERK leading to reduced motility of RCC cells. Interestingly, the potential impact of concomitant statin intake has been recently evaluated in RCC patients treated by targeted therapy or immunotherapy. In this review, we illustrate the most recent data on the preclinical activity of statins in Renal Cell Carcinoma models and discuss the impact of their use on the prevention and survival of patients affected by this tumor.


Assuntos
Carcinoma de Células Renais , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Renais , Apoptose , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Proliferação de Células , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia
8.
Clin Genitourin Cancer ; 20(3): 285-295, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35305916

RESUMO

BACKGROUND: Tyrosine-kinase inhibitors (TKIs) still represent a first-line option for selected patients with metastatic Renal Cell Carcinoma (mRCC). We aimed to compare the real-world efficacy of nivolumab or cabozantinib as second-line therapy in specific mRCC subpopulations. PATIENTS AND METHODS: We retrospectively collected data from 11 centers from Italy, Spain and US. Overall Survival (OS) and Progression-Free Survival (PFS) were analyzed using Kaplan-Meier curves. Cox proportional models were used at univariate and multivariate analyses. RESULTS: We collected data from 343 patients with mRCC, 123 (36%) treated with cabozantinib and 220 (64%) with nivolumab. The median OS resulted longer, but not statistically significant, with nivolumab in patients aged >70 years (21.4 vs. 15.4 months, P = .746), treated with first-line pazopanib (26.8 vs. 11.6 months, P = .450), or with good (47.0 vs. 15.5 months, P = .285) or intermediate-risk criteria (14.4 vs. 11.0 months, P = .357), while it was longer, but even not statistically significant, for cabozantinib in patients who received previous sunitinib (25.7 vs. 21.7 months, P = .638) or with bone metastases (28.4 vs. 24.4 months, P = .871). The median PFS was significantly longer with cabozantinib in patients with clear cell histology (7.8 vs. 5.4 months, P = .026) and in patients with good risk features (12.3 vs. 5.7 months, P = .022). CONCLUSIONS: Nivolumab and cabozantinib resulted active in mRCC patients, showing distinct results when stratified into clinico-pathological features.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Anilidas/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Humanos , Neoplasias Renais/tratamento farmacológico , Nivolumabe/uso terapêutico , Piridinas , Estudos Retrospectivos
9.
Cancers (Basel) ; 11(7)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261741

RESUMO

The expression of the secreted factor Wnt-11 is elevated in several types of cancer, including colorectal cancer, where it promotes cancer cell migration and invasion. Analysis of colorectal cancer gene expression databases associated WNT11 mRNA expression with increased likelihood of metastasis in a subset of patients. WNT11 expression was correlated with the expression of the Wnt receptors FZD6, RYK, and PTK7, and the combined expression of WNT11, FZD6 and RYK or PTK7 was associated with an increased risk of 5-year mortality rates. Immunohistochemical analysis of Wnt-11 in a cohort of 357 colorectal cancer patients found significantly higher Wnt-11 levels in tumors, compared with benign tissue. Elevated Wnt-11 levels occurred more frequently in rectal tumors than in colonic tumors and in tumors from women than men. In univariate analysis, increased Wnt-11 expression was also associated with tumor invasion and increased 5-year mortality. High Wnt-11 levels were not associated with high levels of nuclear ß-catenin, suggesting Wnt-11 is not simply an indicator for activation of ß-catenin-dependent signaling. Expression of Wnt-11 in colorectal cancer cell lines expressing low endogenous Wnt-11 inhibited ß-catenin/Tcf activity and increased ATF2-dependent transcriptional activity. WNT11 gene silencing and antibody-mediated inhibition of Wnt-11 in colorectal cancer cell lines expressing high Wnt-11 reduced their capacity for invasion. Together, these observations suggest that Wnt-11 could be a potential target for the treatment of patients with invasive colorectal cancer.

11.
Oncogene ; 38(17): 3151-3169, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30622340

RESUMO

Increased cancer stem cell content during development of resistance to tamoxifen in breast cancer is driven by multiple signals, including Sox2-dependent activation of Wnt signalling. Here, we show that Sox2 increases and estrogen reduces the expression of the transcription factor Sox9. Gain and loss of function assays indicate that Sox9 is implicated in the maintenance of human breast luminal progenitor cells. CRISPR/Cas knockout of Sox9 reduces growth of tamoxifen-resistant breast tumours in vivo. Mechanistically, Sox9 acts downstream of Sox2 to control luminal progenitor cell content and is required for expression of the cancer stem cell marker ALDH1A3 and Wnt signalling activity. Sox9 is elevated in breast cancer patients after endocrine therapy failure. This new regulatory axis highlights the relevance of SOX family transcription factors as potential therapeutic targets in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , Células-Tronco Neoplásicas/metabolismo , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Mama/citologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular , Proliferação de Células , Células Epiteliais/citologia , Estrogênios/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Fatores de Transcrição SOX9/genética , Transdução de Sinais , Tamoxifeno/farmacologia , Regulação para Cima
12.
Cancers (Basel) ; 10(12)2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30558303

RESUMO

Breast cancer is the most frequently diagnosed cancer in women and the second most common cancer overall, with nearly 1.7 million new cases worldwide every year. Breast cancer patients need accurate tools for early diagnosis and to improve treatment. Biomarkers are increasingly used to describe and evaluate tumours for prognosis, to facilitate and predict response to therapy and to evaluate residual tumor, post-treatment. Here, we evaluate different methods to separate Diaminobenzidine (DAB) from Hematoxylin and Eosin (H&E) staining for Wnt-1, a potential cytoplasmic breast cancer biomarker. A method comprising clustering and Color deconvolution allowed us to recognize and quantify Wnt-1 levels accurately at pixel levels. Experimental validation was conducted using a set of 12,288 blocks of m × n pixels without overlap, extracted from a Tissue Microarray (TMA) composed of 192 tissue cores. Intraclass Correlations (ICC) among evaluators of the data of 0.634 , 0.791 , 0.551 and 0.63 for each Allred class and an average ICC of 0.752 among evaluators and automatic classification were obtained. Furthermore, this method received an average rating of 4.26 out of 5 in the Wnt-1 segmentation process from the evaluators.

13.
Oncogene ; 37(39): 5305-5324, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29858602

RESUMO

Aberrant transforming growth factor-ß (TGF-ß) signaling is a hallmark of the stromal microenvironment in cancer. Dickkopf-3 (Dkk-3), shown to inhibit TGF-ß signaling, is downregulated in prostate cancer and upregulated in the stroma in benign prostatic hyperplasia, but the function of stromal Dkk-3 is unclear. Here we show that DKK3 silencing in WPMY-1 prostate stromal cells increases TGF-ß signaling activity and that stromal cell-conditioned media inhibit prostate cancer cell invasion in a Dkk-3-dependent manner. DKK3 silencing increased the level of the cell-adhesion regulator TGF-ß-induced protein (TGFBI) in stromal and epithelial cell-conditioned media, and recombinant TGFBI increased prostate cancer cell invasion. Reduced expression of Dkk-3 in patient tumors was associated with increased expression of TGFBI. DKK3 silencing reduced the level of extracellular matrix protein-1 (ECM-1) in prostate stromal cell-conditioned media but increased it in epithelial cell-conditioned media, and recombinant ECM-1 inhibited TGFBI-induced prostate cancer cell invasion. Increased ECM1 and DKK3 mRNA expression in prostate tumors was associated with increased relapse-free survival. These observations are consistent with a model in which the loss of Dkk-3 in prostate cancer leads to increased secretion of TGFBI and ECM-1, which have tumor-promoting and tumor-protective roles, respectively. Determining how the balance between the opposing roles of extracellular factors influences prostate carcinogenesis will be key to developing therapies that target the tumor microenvironment.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias da Próstata/patologia , Fator de Crescimento Transformador beta1/metabolismo , Microambiente Tumoral/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Quimiocinas , Humanos , Masculino , Neoplasias da Próstata/metabolismo
14.
Sci Rep ; 8(1): 6613, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29700339

RESUMO

Early diagnosis of laryngeal squamous cell carcinoma (LSCC) at the stage of dysplasia could greatly improve the outcome of affected patients. For the first time we compared the mutational landscape of non-progressing dysplasia (NPD; n = 42) with progressing dysplasia (PD; n = 24), along with patient-matched LSCC biopsies; a total of 90 samples. Using targeted next-generation sequencing identified non-synonymous mutations in six genes (PIK3CA, FGFR3, TP53, JAK3, MET, FBXW7), and mutations were validated by Sanger sequencing and/or qPCR. Analysis was extended in silico to 530 head and neck (HNSCC) cases using TCGA data. Mutations in PIK3CA and FGFR3 were detected in PD and LSCC cases, as well as other HNSCC cases, but absent in NPD cases. In contrast, mutations in JAK3, MET and FBXW7 were found in NPD cases but not PD, LSCC or other HNSCC cases. TP53 was the most frequently mutated gene in both PD and NPD cases. With the exception of R248W, mutations were mutually exclusive. Moreover, five of seven PD mutations were located in motif H2 of p53, whereas none of the NPD mutations were. In summary, we propose that the mutational profile of laryngeal dysplasia has utility for the early detection of patients at risk of progression.


Assuntos
Predisposição Genética para Doença , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , Mutação , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Substituição de Aminoácidos , Biomarcadores Tumorais , Biologia Computacional/métodos , Análise Mutacional de DNA , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco
15.
Oncotarget ; 6(31): 31721-39, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26372732

RESUMO

The heterogeneous nature of breast cancer is a result of intrinsic tumor complexity and also of the tumor microenvironment, which is known to be hypoxic. We found that hypoxia expands different breast stem/progenitor cell populations (cells with increased aldehyde dehydrogenase activity (Aldefluor+), high mammosphere formation capacity and CD44+CD24-/low cells) both in primary normal epithelial and tumor cells. The presence of the estrogen receptor (ER) limits hypoxia-dependent CD44+CD24-/low cell expansion.We further show that the hypoxia-driven cancer stem-like cell enrichment results from a dedifferentiation process. The enhanced mammosphere formation and Aldefluor+ cell content observed in breast cancer cells relies on hypoxia-inducible factor 1α (HIF1α). In contrast, the CD44+CD24-/low population expansion is HIF1α independent and requires prolyl hydroxylase 3 (PHD3) downregulation, which mimics hypoxic conditions, leading to reduced CD24 expression through activation of NFkB signaling. These studies show that hypoxic conditions expand CSC populations through distinct molecular mechanisms. Thus, potential therapies that combine current treatments for breast cancer with drugs that target CSC should take into account the heterogeneity of the CSC subpopulations.


Assuntos
Neoplasias da Mama/patologia , Diferenciação Celular , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Hipóxia/fisiopatologia , Células-Tronco Neoplásicas/patologia , Adulto , Apoptose , Mama/citologia , Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Antígeno CD24/genética , Antígeno CD24/metabolismo , Proliferação de Células , Células Cultivadas , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Células-Tronco Neoplásicas/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Adulto Jovem
16.
EMBO Mol Med ; 6(1): 66-79, 2014 01.
Artigo em Inglês | MEDLINE | ID: mdl-24178749

RESUMO

Development of resistance to therapy continues to be a serious clinical problem in breast cancer management. Cancer stem/progenitor cells have been shown to play roles in resistance to chemo­ and radiotherapy. Here, we examined their role in the development of resistance to the oestrogen receptor antagonist tamoxifen. Tamoxifen­resistant cells were enriched for stem/progenitors and expressed high levels of the stem cell marker Sox2. Silencing of the SOX2 gene reduced the size of the stem/progenitor cell population and restored sensitivity to tamoxifen. Conversely, ectopic expression of Sox2 reduced tamoxifen sensitivity in vitro and in vivo. Gene expression profiling revealed activation of the Wnt signalling pathway in Sox2­expressing cells, and inhibition of Wnt signalling sensitized resistant cells to tamoxifen. Examination of patient tumours indicated that Sox2 levels are higher in patients after endocrine therapy failure, and also in the primary tumours of these patients, compared to those of responders. Together, these results suggest that development of tamoxifen resistance is driven by Sox2­dependent activation of Wnt signalling in cancer stem/progenitor cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição SOXB1/metabolismo , Tamoxifeno/uso terapêutico , Animais , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Retículo Endoplasmático/metabolismo , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Interferência de RNA , Recidiva , Fatores de Transcrição SOXB1/antagonistas & inibidores , Fatores de Transcrição SOXB1/genética , Análise de Sobrevida , Tamoxifeno/farmacologia , Transplante Heterólogo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos
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