975 resultados para breast tumors


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BACKGROUND: The aim of this study was to evaluate the efficacy and tolerability of fulvestrant, an estrogen receptor antagonist, in postmenopausal women with hormone-responsive tumors progressing after aromatase inhibitor (AI) treatment. PATIENTS AND METHODS: This is a phase II, open, multicenter, noncomparative study. Two patient groups were prospectively considered: group A (n=70) with AI-responsive disease and group B (n=20) with AI-resistant disease. Fulvestrant 250 mg was administered as intramuscular injection every 28 (+/-3) days. RESULTS: All patients were pretreated with AI and 84% also with tamoxifen or toremifene; 67% had bone metastases and 45% liver metastases. Fulvestrant administration was well tolerated and yielded a clinical benefit (CB; defined as objective response or stable disease [SD] for >or=24 weeks) in 28% (90% confidence interval [CI] 19% to 39%) of patients in group A and 37% (90% CI 19% to 58%) of patients in group B. Median time to progression (TTP) was 3.6 (95% CI 3.0 to 4.8) months in group A and 3.4 (95% CI 2.5 to 6.7) months in group B. CONCLUSIONS: Overall, 30% of patients who had progressed following prior AI treatment gained CB with fulvestrant, thereby delaying indication to start chemotherapy. Prior response to an AI did not appear to be predictive for benefit with fulvestrant.

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Dans le contexte de la caractérisation des tissus mammaires, on peut se demander ce que l’examen d’un attribut en échographie quantitative (« quantitative ultrasound » - QUS) d’un milieu diffusant (tel un tissu biologique mou) pendant la propagation d’une onde de cisaillement ajoute à son pouvoir discriminant. Ce travail présente une étude du comportement variable temporel de trois paramètres statistiques (l’intensité moyenne, le paramètre de structure et le paramètre de regroupement des diffuseurs) d’un modèle général pour l’enveloppe écho de l’onde ultrasonore rétrodiffusée (c.-à-d., la K-distribution homodyne) sous la propagation des ondes de cisaillement. Des ondes de cisaillement transitoires ont été générés en utilisant la mèthode d’ imagerie de cisaillement supersonique ( «supersonic shear imaging » - SSI) dans trois fantômes in-vitro macroscopiquement homogènes imitant le sein avec des propriétés mécaniques différentes, et deux fantômes ex-vivo hétérogénes avec tumeurs de souris incluses dans un milieu environnant d’agargélatine. Une comparaison de l’étendue des trois paramètres de la K-distribution homodyne avec et sans propagation d’ondes de cisaillement a montré que les paramètres étaient significativement (p < 0,001) affectès par la propagation d’ondes de cisaillement dans les expériences in-vitro et ex-vivo. Les résultats ont également démontré que la plage dynamique des paramétres statistiques au cours de la propagation des ondes de cisaillement peut aider à discriminer (avec p < 0,001) les trois fantômes homogènes in-vitro les uns des autres, ainsi que les tumeurs de souris de leur milieu environnant dans les fantômes hétérogénes ex-vivo. De plus, un modéle de régression linéaire a été appliqué pour corréler la plage de l’intensité moyenne sous la propagation des ondes de cisaillement avec l’amplitude maximale de déplacement du « speckle » ultrasonore. La régression linéaire obtenue a été significative : fantômes in vitro : R2 = 0.98, p < 0,001 ; tumeurs ex-vivo : R2 = 0,56, p = 0,013 ; milieu environnant ex-vivo : R2 = 0,59, p = 0,009. En revanche, la régression linéaire n’a pas été aussi significative entre l’intensité moyenne sans propagation d’ondes de cisaillement et les propriétés mécaniques du milieu : fantômes in vitro : R2 = 0,07, p = 0,328, tumeurs ex-vivo : R2 = 0,55, p = 0,022 ; milieu environnant ex-vivo : R2 = 0,45, p = 0,047. Cette nouvelle approche peut fournir des informations supplémentaires à l’échographie quantitative statistique traditionnellement réalisée dans un cadre statique (c.-à-d., sans propagation d’ondes de cisaillement), par exemple, dans le contexte de l’imagerie ultrasonore en vue de la classification du cancer du sein.

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Los gliomas malignos representan una de las formas más agresivas de los tumores del sistema nervioso central (SNC). De acuerdo con la clasificación de los tumores cerebrales de la Organización Mundial de la Salud (OMS), los astrocitomas han sido categorizados en cuatro grados, determinados por la patología subyacente. Es así como los gliomas malignos (o de alto grado) incluyen el glioma anaplásico (grado III) así como el glioblastoma multiforme (GBM, grado IV),estos últimos los más agresivos con el peor pronóstico (1). El manejo terapéutico de los tumores del SNC se basa en la cirugía, la radioterapia y la quimioterapia, dependiendo de las características del tumor, el estadio clínico y la edad (2),(3), sin embargo ninguno de los tratamientos estándar es completamente seguro y compatible con una calidad de vida aceptable (3), (4). En general, la quimioterapia es la primera opción en los tumores diseminados, como el glioblastoma invasivo y el meduloblastoma de alto riesgo o con metástasis múltiple, pero el pronóstico en estos pacientes es muy pobre (2),(3). Solamente nuevas terapias dirigidas (2) como las terapias anti-angiogénicas (4); o terapias génicas muestran un beneficio real en grupos limitados de pacientes con defectos moleculares específicos conocidos (4). De este modo, se hace necesario el desarrollo de nuevas terapias farmacológicas para atacar los tumores cerebrales. Frente a las terapias los gliomas malignos son con frecuencia quimioresistentes, y esta resistencia parece depender de al menos dos mecanismos: en primer lugar, la pobre penetración de muchas drogas anticáncer a través de la barrera hematoencefálica (BBB: Blood Brain Barrier), la barrera del fluido sangre-cerebroespinal (BCSFB: Blood-cerebrospinal fluid barrier) y la barrera sangre-tumor (BTB: blood-tumor barrier). Dicha resistencia se debe a la interacción de la droga con varios transportadores o bombas de eflujo de droga ABC (ABC: ATP-binding cassette) que se sobre expresan en las células endoteliales o epiteliales de estas barreras. En segundo lugar, estos transportadores de eflujo de drogas ABC propios de las células tumorales confieren un fenotipo conocido como resistencia a multidrogas (MDR: multidrug resistance), el cual es característico de varios tumores sólidos. Este fenotipo también está presente en los tumores del SNC y su papel en gliomas es objeto de investigación (5). Por consiguiente el suministro de medicamentos a través de la BBB es uno de los problemas vitales en los tratamientos de terapia dirigida. Estudios recientes han demostrado que algunas moléculas pequeñas utilizadas en estas terapias son sustratos de la glicoproteína P (Pgp: P-gycoprotein), así como también de otras bombas de eflujo como las proteínas relacionadas con la resistencia a multidrogas (MRPs: multidrug resistance-related proteins (MRPs) o la proteína relacionada con cáncer de seno (BCRP: breast-cancer resistance related protein)) que no permiten que las drogas de este tipo alcancen el tumor (1). Un sustrato de Pgp y BCRP es la DOXOrubicina (DOXO), un fármaco utilizado en la terapia anti cáncer, el cual es muy eficaz para atacar las células del tumor cerebral in vitro, pero con un uso clínico limitado por la poca entrega a través de la barrera hematoencefálica (BBB) y por la resistencia propia de los tumores. Por otra parte las células de BBB y las células del tumor cerebral tienen también proteínas superficiales, como el receptor de la lipoproteína de baja densidad (LDLR), que podría utilizarse como blanco terapéutico en BBB y tumores cerebrales. Es asi como la importancia de este estudio se basa en la generación de estrategias terapéuticas que promuevan el paso de las drogas a través de la barrera hematoencefalica y tumoral, y a su vez, se reconozcan mecanismos celulares que induzcan el incremento en la expresión de los transportadores ABC, de manera que puedan ser utilizados como blancos terapéuticos.Este estudio demostró que el uso de una nueva estrategia basada en el “Caballo de Troya”, donde se combina la droga DOXOrubicina, la cual es introducida dentro de un liposoma, salvaguarda la droga de manera que se evita su reconocimiento por parte de los transportadores ABC tanto de la BBB como de las células del tumor. La construcción del liposoma permitió utilizar el receptor LDLR de las células asegurando la entrada a través de la BBB y hacia las células tumorales a través de un proceso de endocitosis. Este mecanismo fue asociado al uso de estatinas o drogas anticolesterol las cuales favorecieron la expresión de LDLR y disminuyeron la actividad de los transportadores ABC por nitración de los mismos, incrementando la eficiencia de nuestro Caballo de Troya. Por consiguiente demostramos que el uso de una nueva estrategia o formulación denominada ApolipoDOXO más el uso de estatinas favorece la administración de fármacos a través de la BBB, venciendo la resistencia del tumor y reduciendo los efectos colaterales dosis dependiente de la DOXOrubicina. Además esta estrategia del "Caballo de Troya", es un nuevo enfoque terapéutico que puede ser considerado como una nueva estrategia para aumentar la eficacia de diferentes fármacos en varios tumores cerebrales y garantiza una alta eficiencia incluso en un medio hipóxico,característico de las células cancerosas, donde la expresión del transportador Pgp se vió aumentada. Teniendo en cuenta la relación entre algunas vías de señalización reconocidas como moduladores de la actividad de Pgp, este estudio presenta no solo la estrategia del Caballo de Troya, sino también otra propuesta terapéutica relacionada con el uso de Temozolomide más DOXOrubicina. Esta estrategia demostró que el temozolomide logra penetrar la BBB por que interviene en la via de señalización de la Wnt/GSK3/β-catenina, la cual modula la expresión del transportador Pgp. Se demostró que el TMZ disminuye la proteína y el mRNA de Wnt3 permitiendo plantear la hipótesis de que la droga al disminuir la transcripción del gen Wnt3 en células de BBB, incrementa la activación de la vía fosforilando la β-catenina y conduciendo a disminuir la β-catenina nuclear y por tanto su unión al promotor del gen mdr1. Con base en los resultados este estudio permitió el reconocimiento de tres mecanismos básicos relacionados con la expresión de los transportadores ABC y asociados a las estrategias empleadas: el primero fue el uso de las estatinas, el cual condujo a la nitración de los transportadores disminuyendo su actividad por la via del factor de transcripción NFκB; el segundo a partir del uso del temozolomide, el cual metila el gen de Wnt3 reduciendo la actividad de la via de señalización de la la β-catenina, disminuyendo la expresión del transportador Pgp. El tercero consistió en la determinación de la relación entre el eje RhoA/RhoA quinasa como un modulador de la via (no canónica) GSK3/β-catenina. Se demostró que la proteína quinasa RhoA promovió la activación de la proteína PTB1, la cual al fosforilar a GSK3 indujo la fosforilación de la β-catenina, lo cual dio lugar a su destrucción por el proteosoma, evitando su unión al promotor del gen mdr1 y por tanto reduciendo su expresión. En conclusión las estrategias propuestas en este trabajo incrementaron la citotoxicidad de las células tumorales al aumentar la permeabilidad no solo de la barrera hematoencefálica, sino también de la propia barrera tumoral. Igualmente, la estrategia del “Caballo de Troya” podría ser útil para la terapia de otras enfermedades asociadas al sistema nervioso central. Por otra parte estos estudios indican que el reconocimiento de mecanismos asociados a la expresión de los transportadores ABC podría constituir una herramienta clave en el desarrollo de nuevas terapias anticáncer.

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Early detection of breast cancer (BC) with mammography may cause overdiagnosis and overtreatment, detecting tumors which would remain undiagnosed during a lifetime. The aims of this study were: first, to model invasive BC incidence trends in Catalonia (Spain) taking into account reproductive and screening data; and second, to quantify the extent of BC overdiagnosis. We modeled the incidence of invasive BC using a Poisson regression model. Explanatory variables were: age at diagnosis and cohort characteristics (completed fertility rate, percentage of women that use mammography at age 50, and year of birth). This model also was used to estimate the background incidence in the absence of screening. We used a probabilistic model to estimate the expected BC incidence if women in the population used mammography as reported in health surveys. The difference between the observed and expected cumulative incidences provided an estimate of overdiagnosis.Incidence of invasive BC increased, especially in cohorts born from 1940 to 1955. The biggest increase was observed in these cohorts between the ages of 50 to 65 years, where the final BC incidence rates more than doubled the initial ones. Dissemination of mammography was significantly associated with BC incidence and overdiagnosis. Our estimates of overdiagnosis ranged from 0.4% to 46.6%, for women born around 1935 and 1950, respectively.Our results support the existence of overdiagnosis in Catalonia attributed to mammography usage, and the limited malignant potential of some tumors may play an important role. Women should be better informed about this risk. Research should be oriented towards personalized screening and risk assessment tools

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Introduction: Although the use of local flaps in conservative breast surgery (CBS) reconstruction is a reliable technique, little information has been available regarding outcome following the use of perforator flaps. The purpose of this study is to analyze the feasibility, surgical planning and outcome following CBS reconstruction with intercostal artery perforator (ICAP) flap. Patients/methods: Thirteen patients underwent CBS reconstructions with an ICAP flap. These flaps were raised from adjacent tissue located on the lateral and thoracic region and based on perforators originating from the costal and muscular segment of the intercostal vessels. The technique was indicated in patients with small/moderate volume breasts. Results: Mean time of follow-up was 32 months. Flap complications were evaluated and information on patient satisfaction were collected. 61.5 percent had tumors located in the lower-outer quadrants and 69.2 percent had tumors measuring 2 cm or less (T1). Complications occurred in 3 patients (23%), including wound dehiscence in 2 patients and fat necrosis in one. All cases were treated by conservative approach with a good result. No flap loss or wound infection were reported. 90 percent were either satisfied or very satisfied with their result. Conclusion: The ICAP flap is a reliable technique for immediate CBS reconstruction. The technique is advantageous because it does not require the use of muscle transfer, with minimum donor site morbidity. Success depends on patient selection, coordinated planning with the oncological surgeon and careful intra-operative management. (C) 2011 Elsevier Ltd. All rights reserved.

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Metallothioneins (MTs) belong to a family of cysteine-rich, metal-binding intracellular proteins, which have been linked with cell proliferation. In this study, expression levels of the 8 known MT-1 and MT-2 functional isoforms in human invasive ductal breast cancer specimens were determined by RT–PCR. The expression profiles of the MT protein and MT-2A mRNA were further evaluated in 79 cases of human invasive ductal breast carcinoma by immunohistochemistry and in situ hybridization, and correlated with cancer cell proliferation (determined by Ki-67 nuclear antigen immunolabeling). MT-1A, MT-1E, MT-1F, MT-1G, MT-1H, MT-1X and MT-2A but not MT-1B, were detected in breast cancer tissue samples. The MT-2A mRNA transcript was the highest among all the isoforms detected. A positive correlation was observed between MT-2A mRNA and MT protein expression with Ki-67 labeling (P = 0.0003 and P < 0.0001, respectively) but not with apoptosis (P = 0.1244 and P = 0.8189, respectively). Co-localization of the MT protein and Ki-67 nuclear antigen in breast cancer cells was demonstrated by double immunofluorescence staining. There was also significantly higher MT protein and MT-2A mRNA expression in histological grade 3 tumors than in histological grade 1 and 2 tumors. The finding that MT 2A appears to be the main isoform associated with cell proliferation in invasive ductal breast cancer tissues, may have therapeutic implications.

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Matrine, one of the main components extracted from a traditional Chinese herb, Sophora flavescens Ait, has displayed anti-cancer activity in several types of cancer cells. This study aims to evaluate the therapeutic benefits of matrine on primary and metastatic breast cancer. Matrine inhibited the viability of and induced apoptosis in human MCF-7 and mouse 4T1 breast cancer cells in a dose-dependent manner in vitro as shown by MTT assay, flow cytometry and laser scanning confocal microscopy. Administration of matrine inhibited the growth of primary tumors and their metastases to lungs and livers, in a dose-dependent manner, in a highly metastatic model of 4T1 breast cancer established in syngeneic Balb/c mice. Tumors from matrine-treated mice had a smaller proliferation index, shown by immunostaining with an anti-Ki-67 antibody, a greater apoptosis index, shown by TUNEL-staining, and a less microvessel density, shown by immunostaining with an anti-CD31 A antibody, compared to the controls. Western blot analysis of tumoral homogenates indicated that matrine therapy reduced the ratio of Bcl-2/Bax, downregulated the expressions of VEGF and VEGFR-2, and increased the activation of caspase-3 and caspase-9. This study suggests matrine may be a potent agent, from a natural resource, for treating metastatic breast cancer because of its anti-apoptotic, anti-proliferative and anti-angiogenic activities.

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Thrombocytopenia in patients with solid malignancy can be caused by bone marrow involvement or toxicity from anticancer therapy; however, it could rarely be the first presentation of a tumor such as breast cancer or lymphoma. Hematological paraneoplastic syndromes such as paraneoplastic thrombocytopenia and/or immune thrombocytopenic purpura (ITP) are well described as secondary findings simultaneously with malignancies such as breast cancer and lymphoma. Other hematological conditions such as severe amegakaryocytic thrombocytopenia, thrombotic thrombocytopenic purpura (TTP), and myelodysplastic syndromes (MDS) have also rarely been described as a possible paraneoplastic process complicating solid tumors. On the one hand, occult disseminated malignancy may mimic ITP and TTP, leading to diagnostic and therapeutic problems. On the other hand, thrombocytopenia could be the first manifestation of cancer.

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EpCAM is expressed at low levels in a variety of normal human epithelial tissues, but is overexpressed in 70–90% of carcinomas. From a clinico-pathological point of view, this has both prognostic and therapeutic significance. EpCAM was first suggested as a therapeutic target for the treatment of epithelial cancers in the 1990s. However, following several immunotherapy trials, the results have been mixed. It has been suggested that this is due, at least in part, to an unknown level of EpCAM expression in the tumors being targeted. Thus, selection of patients who would benefit from EpCAM immunotherapy by determining EpCAM status in the tumor biopsies is currently undergoing vigorous evaluation. However, current EpCAM antibodies are not robust enough to be able to detect EpCAM expression in all pathological tissues.

Here we report a newly developed EpCAM RNA aptamer, also known as a chemical antibody, which is not only specific but also more sensitive than current antibodies for the detection of EpCAM in formalin-fixed paraffin-embedded primary breast cancers. This new aptamer, together with our previously described aptamer, showed no non- specific staining or cross-reactivity with tissues that do not express EpCAM. They were able to reliably detect target proteins in breast cancer xenograft where an anti-EpCAM antibody (323/A3) showed limited or no reactivity. Our results demonstrated a more robust detection of EpCAM using RNA aptamers over antibodies in clinical samples with chromogenic staining. This shows the potential of aptamers in the future of histopathological diagnosis and as a tool to guide targeted immunotherapy.

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Smoothened (Smo) is a G protein-coupled receptor protein encoded by the Smo gene of the hedgehog signalling pathway, which is thought to play an important role in maintaining organ patterning, cell differentiation and self-renewal. The possible role of Smo in the process of tumorigenesis and metastasis of breast cancer still remains unclear. The present experiments were to investigate the effect of Smo on activating breast cancer stem-like CD44(+)CD24(-) cells and the tumorigenesis and metastasis of breast cancer. By injected CD44(+)CD24(-) cells (1×10(4)) into the cleared fat pad of NOD/SCID mice, it was observed that CD44(+)CD24(-) cells possess higher tumor-initiating capacity and metastasis properties than equal numbers of non-CD44(+)CD24(-) cells. The mRNA and protein expressions of Smo in CD44(+)CD24(-) cells were higher than those in non-CD44(+)CD24(-) cells, indicating that Smo may play a role in maintaining breast cancer stem cell features. qRT-PCR results revealed that expressions of STAT3, Bcl-2 and cyclinD1 mRNA in MCF-7 cells were decreased after transfected by Smo siRNA. In addition, the expressions of MMP-2 and MMP-9 were downregulated in MCF-7 cells after Smo expression was inhibited. Smo inhibition may be a possible therapeutic target that potentially suppresses breast tumor formation and development.

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Sodium Iodide Symporter (NIS), a therapeutic gene, was studied for the first time in retinoblastoma (RB) correlating the expression with clinicopathological invasiveness of the tumor. The specificity of EpCAM based NIS gene therapy was demonstrated in breast cancer cell as a proof of concept model via 1) EpCAM as tissue specific promoter and 2) nanoformulation, both of which showed encouraging outcomes. In addition, for the first time the upregulated expression of splice variants of survivin, Bax and Bcl-2 in RB tumors was explored indicating their possible role in tumor progression through apoptosis dysregulation. Thus, the above study achieved a profound knowledge about NIS and apoptotic genes in extrathyroidal tumors.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Scintimammography using Tc-99m-sestamibi is a noninvasive and painless diagnostic imaging method that is used to detect breast cancer when mammography is inconclusive Because of the advantages of labeling v '7,ith Tc-99m-sestamibi and its high efficiency in detecting carcinomas, it is the most widespread agent for this purpose Its accumulation in the tumor has multifactorial causes and does not depend on the presence of architectural distortion or local or diffuse density variation in the breast The objective of tfiis study was to evaluate the accuracy of scintimammography 1 for detecting breast cancer One hundred and fifty-seven patients presenting 158 palpable and non-palpable breast nodules were evaluated Three patients were male and 154 were female, aged between 14 and 81 years All patients underwent scintimammography, and the nodule was subjected i to cytological or histological study, i e, the gold standard for diagnosing cancer One hundred and eleven malignant and 47 benign nodules were detected, with predominance of ductal carcinomas (n=94) and fibroadenoma/fibrocysiic condition (n=11/n=11), respectively The mean size was 3 11 cm (7-10 cm) among the malignant nodules and 2 07 cm among the benign nodules (0 5-10 cm) The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 89, 89, 95, 78 and 89%, respectively Analysis on the histological types showed that the technique was more effective on tumors that were more aggressive, such as ductal carcinoma In this study, Tc-99m-sestamibi scintim immography was shown to be an important tool for diagnosing breast cancer when mammography was inconclusive

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Background: Locally advanced breast cancer (LABC) is still common in developing countries. The association between neoadjuvant chemotherapy (NC) and oncoplastic surgery (OS) might provide an oncological treatment with satisfactory aesthetic results.Purpose: The goal was to demonstrate if oncoplastic surgical techniques can be utilized to treat LABC which was submitted to neoadjuvant chemotherapy.Methods: This prospective clinical trial included breast cancer patients, clinical stage III, who underwent established NC regimen. All patients underwent preoperative planning to control the tumor size and to define the surgical technique. A detailed analysis of the pathological specimen was performed.Results: 50 patients were assessed and surgically treated. Tumor size ranged from 3.0 to 14.0 cm (median 6.5 cm). Pathologic response was rated as stable, progressive, partial response, and complete response in 10%, 8%, 80% and 2% of the cases, respectively. Seventeen (34%) patients were submitted to OS. No patient had positive margins. Skin involvement was presented in 36% of pathologic specimen.Conclusions: Oncoplastic surgical techniques for selected patients decrease the rates of radical surgery despite large tumors. (www.clinicaltrials.gov, NCT00820690). (C) 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.