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1.
J Am Coll Radiol ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38461915

RESUMO

Breast cancer incidence and mortality continue to increase in Africa. In Tanzania, breast cancer is the second leading cause of cancer death for women, and breast cancer incidence and mortality are projected to increase by 80% by 2030. Education gaps among health care workers, delayed presentation, limited screening, and low health literacy all pose significant challenges to providing optimal breast cancer care. Considering these factors, it is imperative to train expert breast radiologists. We present a collaborative breast radiology training program in Tanzania aimed at building local capacity to address national breast cancer challenges. Although cancer control in Africa faces many challenges, developing customized training programs for breast radiology, in conjunction with national cancer programs, may represent a key strategy for addressing breast cancer.

2.
J Breast Imaging ; 6(3): 277-287, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38537570

RESUMO

OBJECTIVE: We investigated patient experience with screening contrast-enhanced mammography (CEM) to determine whether a general population of women with dense breasts would accept CEM in a screening setting. METHODS: In this institutional review board-approved prospective study, patients with heterogeneous and extremely dense breasts on their mammogram were invited to undergo screening CEM and complete pre-CEM and post-CEM surveys. On the pre-CEM survey, patients were asked about their attitudes regarding supplemental screening in general. On the post-CEM survey, patients were asked about their experience undergoing screening CEM, including causes and severity of any discomfort and whether they would consider undergoing screening CEM again in the future or recommend it to a friend. RESULTS: One hundred sixty-three women were surveyed before and after screening CEM. Most patients, 97.5% (159/163), reported minimal or no unpleasantness associated with undergoing screening CEM. In addition, 91.4% (149/163) said they would probably or very likely undergo screening CEM in the future if it cost the same as a traditional screening mammogram, and 95.1% (155/163) said they would probably or very likely recommend screening CEM to a friend. Patients in this study, who were all willing to undergo CEM, more frequently reported a family history of breast cancer than a comparison cohort of women with dense breasts (58.2% vs 47.1%, P = .027). CONCLUSION: Patients from a general population of women with dense breasts reported a positive experience undergoing screening CEM, suggesting screening CEM might be well received by this patient population, particularly if the cost was comparable with traditional screening mammography.


Assuntos
Densidade da Mama , Neoplasias da Mama , Meios de Contraste , Mamografia , Humanos , Feminino , Mamografia/métodos , Pessoa de Meia-Idade , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Meios de Contraste/administração & dosagem , Estudos Prospectivos , Idoso , Adulto , Detecção Precoce de Câncer/métodos , Inquéritos e Questionários , Mama/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Programas de Rastreamento/métodos
3.
J Breast Imaging ; 5(2): 125-134, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38416932

RESUMO

OBJECTIVE: We sought to identify patient factors associated with patient-reported screening behaviors in women with dense breasts. METHODS: An IRB-approved survey study of women with dense breasts presenting for annual screening mammography at an outpatient imaging center was previously conducted from March 2017 to February 2018. The survey included questions regarding mammographic screening frequency and recent participation in supplemental screening. These survey data were combined post hoc with clinical and demographic data and socioeconomic data imputed from census data. Logistic regression was used to identify patient factors associated with reported screening behaviors. RESULTS: Surveys were completed by 508 women (median age, 59.0 years; range, 31.0-86.0 years) with dense breasts. Multivariable analysis demonstrated an independent association of undergoing mammographic screening annually with a history of discussing breast density with a doctor (adjusted odds ratio [AOR], 2.60; P = 0.019). Undergoing supplemental screening in the previous three years was independently associated with younger age (AOR, 1.59; P = 0.004), strong family history of breast cancer (AOR, 3.84; P = 0.027), higher perceived personal risk for breast cancer (AOR, 3.47; P = 0.004), and increased concern about radiation associated with screening examinations (AOR, 3.31; P = 0.006). CONCLUSION: Women with dense breasts who had discussed breast density with a doctor were more likely to report undergoing annual screening mammography, while younger women and women with a strong family history of breast cancer, higher perceived personal risk for breast cancer, or greater concern about radiation were more likely to report recently undergoing supplemental screening.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias da Mama/diagnóstico , Densidade da Mama , Mamografia/métodos , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos
4.
J Breast Imaging ; 4(1): 19-24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35103252

RESUMO

OBJECTIVE: Some vendors have created algorithms that generate synthetic 2D (s2D) images from a digital breast tomosynthesis (DBT) dataset to reduce the radiation from obtaining a separate 2D digital mammography (DM). This study evaluated the visibility of amorphous calcifications on 2D DM versus s2D on screening mammography. METHODS: This IRB-approved, retrospective, reader study included screening mammograms from 36 women who received screening DBT exams where both 2D DM and s2D images were obtained: 28 screening mammograms that were eventually given BI-RADS category 4 or 5 for amorphous calcifications and 8 BI-RADS category 1 or 2 screening exams. Two rounds of interpretation were conducted with a six-week washout period. Cases were randomized to display either the 2D DM or s2D images, which were then alternated in the second round. Four fellowship-trained breast radiologists determined whether a study merited recall for calcifications. If so, they rated calcification visibility on a scale of 1 to 5. McNemar chi-square tests were conducted to assess differences in recall rates and Wilcoxon signed rank tests were used to examine shifts in visibility. RESULTS: There was no difference in detection rates of amorphous calcifications between 2D DM and s2D, which were 75.9% and 75.0%, respectively (P = 1.000). Collectively, amorphous calcifications were more visible on s2D than 2D DM, with mean visibility scores of 3.4 versus 3.0, respectively (P = 0.005). CONCLUSION: Synthetic 2D did not change identification of amorphous calcifications compared to 2D DM, and readers considered them more visible on average.

5.
Eur J Radiol ; 131: 109237, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32905954

RESUMO

PURPOSE: To evaluate the surgical upgrade rate to malignancy and high-risk lesions in cases of papilloma without atypia diagnosed with imaging-guided percutaneous core needle biopsy (CNB) and to determine whether any lesion imaging features, biopsy techniques, and pathological factors can predict lesion upgrade to help guide clinical management. MATERIALS AND METHODS: Benign papillomas without atypia (n = 399) diagnosed with CNB were retrospectively reviewed. The surgical upgrade rate to malignancy or high-risk lesion (atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in-situ, flat epithelial atypia and atypical papilloma) was determined. Detection modality (i.e. mammography, ultrasonography (US), magnetic resonance imaging (MRI)), lesion type and size, biopsy-guidance modality (US, stereotactic, MRI), biopsy needle size (<14 G vs ≥14 G), use of vacuum assistance, and presenting symptoms were statistically analyzed. The reference standard for evaluation of upgrade was either excision or at least 24 months of imaging follow-up. Chi Square test and Fisher exact tests were performed for categorical variables, and the Mann-Whitney-U test was used for continuous variables. RESULTS: Ultrasound was the predominant biopsy modality (78.4 %, p < 0.001). Of the 399 benign papilloma lesions in 329 women, 239 (59.9 %) were excised and 93 others were followed for at least 24 months (total of 332). Of these 332 lesions, 7 (2.1 %) were upgraded to ductal carcinoma in-situ and 41 (12.3 %) to high-risk lesions at excision. Larger lesion size (≥15 mm, p = 0.009), smaller biopsy needle size (≥14 G, p = 0.027), and use of spring-loaded biopsy device (p = 0.012) were significantly associated with upgrade to atypia. Only lesion size (≥15 mm, p = 0.02) was associated with upgrade to cancer. CONCLUSION: Upgrade to malignancy of biopsy-proven benign papillomas without atypia at the time of surgery was sufficiently low (2.1 %) to support non-operative management. Surgery may be performed for selected cases- those with larger lesion size and those whose biopsies were performed with smaller spring-loaded biopsy needles.


Assuntos
Biópsia por Agulha , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Biópsia Guiada por Imagem , Papiloma/diagnóstico por imagem , Papiloma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/instrumentação , Biópsia por Agulha/métodos , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Distribuição de Qui-Quadrado , Feminino , Seguimentos , Humanos , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética , Mamografia , Pessoa de Meia-Idade , Papiloma/patologia , Estudos Retrospectivos , Estatísticas não Paramétricas , Ultrassonografia Mamária
6.
Emerg Radiol ; 26(2): 123-131, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30377859

RESUMO

PURPOSE: The purpose of this study is to (1) assess the diagnostic yield of ultrasounds performed in the emergency department for suspected breast abscess and determine the rates of reimaging, discordance, and emergent intervention in a large, busy safety net hospital and (2) determine clinical factors significantly associated with abscess as a way to improve patient selection for emergent breast ultrasounds. METHODS: A total of 581 consecutive breast ultrasounds performed in the emergency department for suspected abscess over 15 months were retrospectively reviewed for imaging, demographics, laboratory data, and physical exam findings. Breast abscess was confirmed by combining imaging, clinical, and laboratory data. Linear logistic regression analysis estimated the likelihood of abscess, and the cross-validated area under the receiver operating characteristic curve (AUC) evaluated diagnostic performance. RESULTS: Final diagnoses included abscess (153/581, 26%), cancer (29/581, 5%), granulomatous mastitis (41/581, 7%), normal (120/581, 21%), and other/indeterminate (238/581, 41%). Factors associated with abscess included induration, fluctuance, erythema, drainage, smoking, diabetes, and Black race. Based on these factors, the AUC of the characteristics predictive of abscess was 0.77 (CI, 0.72-0.81). Six breast cancers were not diagnosed on ultrasound. 40% of ultrasounds (231/581) were considered incomplete/inadequate. CONCLUSION: 74% (428/581) of emergent breast ultrasounds in our population were negative for abscess, while 21% (6/29) of cancers were not diagnosed, and 40% (231/581) of exams were incomplete/inadequate. Patient selection for emergent ultrasounds can be improved, allowing patients with a low likelihood of abscess to be imaged in a more optimal setting.


Assuntos
Abscesso/diagnóstico por imagem , Doenças Mamárias/diagnóstico por imagem , Serviço Hospitalar de Emergência/estatística & dados numéricos , Provedores de Redes de Segurança , Ultrassonografia Mamária/estatística & dados numéricos , Abscesso/patologia , Adulto , Doenças Mamárias/patologia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Radiographics ; 37(2): 366-382, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28186859

RESUMO

Breast implants are frequently encountered on breast imaging studies, and it is essential for any radiologist interpreting these studies to be able to correctly assess implant integrity. Ruptures of silicone gel-filled implants often occur without becoming clinically obvious and are incidentally detected at imaging. Early diagnosis of implant rupture is important because surgical removal of extracapsular silicone in the breast parenchyma and lymphatics is difficult. Conversely, misdiagnosis of rupture may prompt a patient to undergo unnecessary additional surgery to remove the implant. Mammography is the most common breast imaging examination performed and can readily depict extracapsular free silicone, although it is insensitive for detection of intracapsular implant rupture. Ultrasonography (US) can be used to assess the internal structure of the implant and may provide an economical method for initial implant assessment. Common US signs of intracapsular rupture include the "keyhole" or "noose" sign, subcapsular line sign, and "stepladder" sign; extracapsular silicone has a distinctive "snowstorm" or echogenic noise appearance. Magnetic resonance (MR) imaging is the most accurate and reliable means for assessment of implant rupture and is highly sensitive for detection of both intracapsular and extracapsular rupture. MR imaging findings of intracapsular rupture include the keyhole or noose sign, subcapsular line sign, and "linguine" sign, and silicone-selective MR imaging sequences are highly sensitive to small amounts of extracapsular silicone. ©RSNA, 2017.


Assuntos
Implantes de Mama/efeitos adversos , Mamoplastia , Imagem Multimodal , Falha de Prótese , Feminino , Humanos , Ruptura , Silicones
8.
Acad Radiol ; 24(1): 111-115, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27818005

RESUMO

RATIONALE AND OBJECTIVES: The purposes of this study were to provide a case-based overview of various immune-mediated side effects detected by 18F-Fluorodeoxyglucose (F-18 FDG) positron emission tomography-computed tomography (PET-CT) in the patients receiving ipilimumab immunotherapy for treatment of malignant melanoma, and discuss the importance of recognizing immune-mediated side effects in the use of F-18 FDG PET-CT for monitoring therapeutic effects of ipilimumab on metastatic melanoma. MATERIALS AND METHODS: This is a retrospective case series study of the patients diagnosed with melanoma who were subjected to immunomodulating therapy with ipilimumab. F-18 FDG PET-CT findings were reviewed, and the patients with immune-mediated side effects were selected for further analysis, in conjunction with review of clinical progress notes, the results of laboratory tests, and findings of other imaging tests. RESULTS: Four patients with immune-mediated side effects were identified among the patients being treated with ipilimumab and subjected to F-18 FDG PET-CT for monitoring therapeutic effects. These immune mediated side effects include new findings of abnormal increased FDG uptake associated with immune-mediated pancreatitis and hypophysitis, as well as immune-mediated thyroiditis and colitis reported previously. CONCLUSIONS: Various immune-mediated side effects were detected by F-18 FDG PET-CT in the patients subjected to immunomodulating therapy with ipilimumab. It is essential for the interpreting provider to recognize and differentiate abnormal FDG uptake associated with immune-mediated side effects from hypermetabolic malignant lesions when using F-18 FDG PET-CT for monitoring therapeutic effects of ipilimumab on melanoma lesions.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Colite/induzido quimicamente , Feminino , Fluordesoxiglucose F18 , Humanos , Hipofisite/induzido quimicamente , Imunoterapia/efeitos adversos , Ipilimumab , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Pancreatite/induzido quimicamente , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Tireoidite/induzido quimicamente , Tomografia Computadorizada por Raios X/métodos
9.
Cancer Cell ; 22(5): 683-97, 2012 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-23153540

RESUMO

To define the mutation spectrum in non-Down syndrome acute megakaryoblastic leukemia (non-DS-AMKL), we performed transcriptome sequencing on diagnostic blasts from 14 pediatric patients and validated our findings in a recurrency/validation cohort consisting of 34 pediatric and 28 adult AMKL samples. Our analysis identified a cryptic chromosome 16 inversion (inv(16)(p13.3q24.3)) in 27% of pediatric cases, which encodes a CBFA2T3-GLIS2 fusion protein. Expression of CBFA2T3-GLIS2 in Drosophila and murine hematopoietic cells induced bone morphogenic protein (BMP) signaling and resulted in a marked increase in the self-renewal capacity of hematopoietic progenitors. These data suggest that expression of CBFA2T3-GLIS2 directly contributes to leukemogenesis.


Assuntos
Fatores de Transcrição Kruppel-Like/genética , Leucemia Megacarioblástica Aguda/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/genética , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Criança , Inversão Cromossômica , Cromossomos Humanos Par 16 , Drosophila/genética , Drosophila/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Humanos , Leucemia Megacarioblástica Aguda/classificação , Leucemia Megacarioblástica Aguda/diagnóstico , Camundongos , Proteínas de Fusão Oncogênica/metabolismo , Proteínas de Fusão Oncogênica/fisiologia , Prognóstico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/fisiologia , Análise de Sequência de RNA , Transdução de Sinais
10.
Proc Natl Acad Sci U S A ; 106(31): 12944-9, 2009 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-19651601

RESUMO

Pediatric de novo acute myeloid leukemia (AML) is an aggressive malignancy with current therapy resulting in cure rates of only 60%. To better understand the cause of the marked heterogeneity in therapeutic response and to identify new prognostic markers and therapeutic targets a comprehensive list of the genetic mutations that underlie the pathogenesis of AML is needed. To approach this goal, we examined diagnostic leukemic samples from a cohort of 111 children with de novo AML using single-nucleotide-polymorphism microarrays and candidate gene resequencing. Our data demonstrate that, in contrast to pediatric acute lymphoblastic leukemia (ALL), de novo AML is characterized by a very low burden of genomic alterations, with a mean of only 2.38 somatic copy-number alterations per leukemia, and less than 1 nonsynonymous point mutation per leukemia in the 25 genes analyzed. Even more surprising was the observation that 34% of the leukemias lacked any identifiable copy-number alterations, and 28% of the leukemias with recurrent translocations lacked any identifiable sequence or numerical abnormalities. The only exception to the presence of few mutations was acute megakaryocytic leukemias, with the majority of these leukemias being characterized by a high number of copy-number alterations but rare point mutations. Despite the low overall number of lesions across the patient cohort, novel recurring regions of genetic alteration were identified that harbor known, and potential new cancer genes. These data reflect a remarkably low burden of genomic alterations within pediatric de novo AML, which is in stark contrast to most other human malignancies.


Assuntos
Dosagem de Genes , Leucemia Mieloide Aguda/genética , Mutação , Polimorfismo de Nucleotídeo Único , Criança , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Cinesinas/genética , Perda de Heterozigosidade , Masculino , Miosinas/genética , Proteínas Proto-Oncogênicas/genética , RNA Longo não Codificante , Proteína 1 Parceira de Translocação de RUNX1 , Fatores de Transcrição/genética , Translocação Genética
11.
BMC Cancer ; 8: 357, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19046423

RESUMO

BACKGROUND: The germline TP53-R337H mutation is strongly associated with pediatric adrenocortical tumors (ACT) in southern Brazil; it has low penetrance and limited tissue specificity in most families and therefore is not associated with Li-Fraumeni syndrome. However, other tumor types, mainly breast cancer, have been observed in carriers of several unrelated kindreds, raising the possibility that the R337H mutation may also contribute to breast tumorigenesis in a genetic background-specific context. METHODS: We conducted a case-control study to determine the prevalence of the R337H mutation by sequencing TP53 exon 10 in 123 women with breast cancer and 223 age- and sex-matched control subjects from southern Brazil. Fisher's test was used to compare the prevalence of the R337H. RESULTS: The R337H mutation was found in three patients but in none of the controls (p = 0.0442). Among the carriers, two had familial history of cancer meeting the Li-Fraumeni-like criteria. Remarkably, tumors in each of these three cases underwent loss of heterozygosity by eliminating the mutant TP53 allele rather than the wild-type allele. Polymorphisms were identified within the TP53 (R72P and Ins16) and MDM2 (SNP309) genes that may further diminish TP53 tumor suppressor activity. CONCLUSION: These results demonstrate that the R337H mutation can significantly increase the risk of breast cancer in carriers, which likely depends on additional cooperating genetic factors. These findings are also important for understanding how low-penetrant mutant TP53 alleles can differentially influence tumor susceptibility.


Assuntos
Neoplasias da Mama/genética , Genes p53 , Mutação em Linhagem Germinativa , Proteína Supressora de Tumor p53/genética , Adulto , Brasil , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Interpretação Estatística de Dados , Família , Feminino , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Masculino , Polimorfismo Genético , Proteínas Proto-Oncogênicas c-mdm2/genética
12.
Cancer ; 113(6): 1453-61, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18704985

RESUMO

BACKGROUND: Osteosarcoma cell lines and tumors have been shown to express epidermal growth factor receptor (EGFR) and harbor amplifications at the EGFR locus. In this study, the authors further analyzed the genomic features of EGFR in osteosarcoma tumors and investigated whether they correlate with phosphatase and tensin homolog (PTEN) expression and copy number status. METHODS: EGFR and PTEN expression was assessed by immunohistochemistry (n = 28), and copy number alterations at the EGFR and PTEN loci were surveyed using Affymetrix (Santa Clara, Calif) 50K single nucleotide polymorphism (SNP) arrays (n = 31) and fluorescence in situ hybridization (FISH) (n = 27). The EGFR tyrosine kinase domain was sequenced to survey for activating mutations (n = 34). In addition, EGFRvIII expression was assessed using reverse transcriptase polymerase chain reaction (n = 24). Results were correlated with available clinical information on 59 patients, with a median age of 14.1 years (range, 5-23 years) and median follow-up of 4.4 years. RESULTS: EGFR expression was detected in the majority of osteosarcoma tumors surveyed (23 of 28; 82%). SNP arrays revealed evidence of frequent copy number gains at 7p11.2 and losses at 10q23.21. A sizeable subset (16 of 27 cases; 59%) showed gains at the EGFR locus using FISH (amplification in 4 of 27 [15%] and balanced chromosome 7 polysomy in 12 of 27 [44%]), and 12 cases showed deletions at the PTEN locus (biallelic deletions in 4 of 27 [15%] and monoallelic deletion in 9 of 27 [33%]). No activating mutations in the EGFR tyrosine kinase domain, EGFRvIII expression, or association with clinical findings were detected. CONCLUSIONS: EGFR expression and genomic gains at the EGFR locus are prevalent in osteosarcoma tumors, which also commonly harbor deletions at the PTEN locus.


Assuntos
Neoplasias Ósseas/genética , Receptores ErbB/genética , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Osteossarcoma/genética , PTEN Fosfo-Hidrolase/genética , Adolescente , Adulto , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Receptores ErbB/metabolismo , Feminino , Amplificação de Genes , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Masculino , Mutação/genética , Osteossarcoma/metabolismo , Osteossarcoma/patologia , PTEN Fosfo-Hidrolase/metabolismo , Polimorfismo de Nucleotídeo Único , Prognóstico , Taxa de Sobrevida
13.
Invest Ophthalmol Vis Sci ; 48(4): 1853-63, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17389521

RESUMO

PURPOSE: In proliferative vitreoretinopathy (PVR), retinal pigment epithelial (RPE) cells enter the vitreous and proliferate. They become fibroblast-like and participate in the formation of contractile membranes, which can lead to retinal detachment. Vitreous treatment of RPE cells in vitro results in similar morphologic changes. This study was conducted to examine vitreous-induced modulation of gene expression in RPE cells. METHODS: Low-passage human RPE cell lines derived from three donors were each treated for 6, 12, 24, or 48 hours with complete medium or complete medium containing 25% vitreous. Changes in mRNA levels were examined by using microarrays. Real-time quantitative PCR (qPCR) was used to measure mRNA expression of a subset of genes in cells from three additional donors. Immunohistochemistry and immunoblot analysis were used to examine protein expression. RESULTS: Vitreous treatment caused a progressive reprogramming of gene expression. qPCR confirmed vitreous modulation of mRNA levels of 10 of 10 genes. Changes consistent with a transition from an epithelial to a mesenchymal phenotype were observed. Downregulated genes included genes associated with differentiated RPE cells. Upregulated genes included genes associated with stress and inflammation. Pathway analysis indicated that the transforming growth factor-beta/bone morphogenetic protein (BMP) pathway and the focal adhesion pathway may play a role in this process. BMP-2 protein and mRNA were increased. CONCLUSIONS: Despite the biological variation in vitreous and RPE donors, vitreous reproducibly modulated a limited number of mRNAs. Many of these changes were consistent with the more fibroblast-like appearance of vitreous-treated cells and with the pathobiology of PVR. TGF-beta and BMP-2 may be important modulators of vitreous-induced changes in gene expression.


Assuntos
Proteínas do Olho/genética , Expressão Gênica/fisiologia , Epitélio Pigmentado Ocular/metabolismo , Corpo Vítreo/fisiologia , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Immunoblotting , Imuno-Histoquímica , Análise de Sequência com Séries de Oligonucleotídeos , Epitélio Pigmentado Ocular/citologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
14.
Mol Vis ; 13: 66-78, 2007 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-17277740

RESUMO

PURPOSE: When human retinal pigment epithelial (RPE) cells come in contact with vitreous, they undergo changes in gene expression that include inflammatory and anti-oxidant responses. The effects of vitreous on expression of heme oxygenase-1 (HO-1), metallothionein (MT) -1a and -2a, and c-fos were investigated. Activator protein-1 (AP-1) binding sites are located in the promoter region of HO-1 and MT genes and the effects of vitreous on c-fos activity were investigated. METHODS: Low passage cultures of human RPE cells were grown in the presence or absence of vitreous or transforming growth factor-beta (TGF-beta). The expression of HO-1 and MTs was measured by real time PCR and, in the case of HO-1, by immunoblotting and immunofluorescence microscopy. Specific inhibitors were used to investigate possible signaling pathways. The effect of vitreous on activation of AP-1 transcription factor was determined by immunoblotting, electrophoretic mobility shift assays, or immunofluorescence microscopy. RESULTS: Incubation of RPE cells with vitreous resulted in increased expression of HO-1, MT-1a and MT-2a. TGF-beta caused an increase in HO-1 expression, although not to the extent mediated by vitreous, but had little effect on MT expression. Addition of inhibitors of TGF-beta signaling (SB431542 or TGF-beta-neutralizing antibodies) decreased the vitreous induction of HO-1. Several reactive oxygen species (ROS) quenchers inhibited the TGF-beta-induced or vitreous-induced elevation of HO-1 mRNA but had no effect on vitreous-mediated induction of MT expression. Inhibitors of the mitogen-activated protein kinase (p38MAPK; SB203580) and Jun N-terminal kinase (JNK; SP600125) pathways inhibited vitreous-induction of HO-1. C-fos, a component of AP-1 transcription factor complexes, exhibited increased expression and activation in the presence of vitreous. CONCLUSIONS: TGF-beta, a known component of vitreous, can account for some but not all of the regulation of the anti-oxidant, anti-inflammatory HO-1 gene in human RPE cells, but it does not participate in the vitreous-mediated upregulation of MTs. Both vitreous and TGF-beta signals increased HO-1 expression via ROS but the latter were not involved in vitreous-mediated MT expression. Increased p38, JNK, and c-fos activation may be implicated in vitreous modulation of HO-1.


Assuntos
Heme Oxigenase-1/biossíntese , Epitélio Pigmentado Ocular/citologia , Epitélio Pigmentado Ocular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta/fisiologia , Corpo Vítreo/fisiologia , Receptores de Ativinas Tipo I/antagonistas & inibidores , Benzamidas/farmacologia , Transporte Biológico/fisiologia , Núcleo Celular/metabolismo , Células Cultivadas , Dioxóis/farmacologia , Ativação Enzimática/fisiologia , Heme Oxigenase-1/genética , Humanos , Metalotioneína/genética , Metalotioneína/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Isoformas de Proteínas/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Fator de Transcrição AP-1/metabolismo , Corpo Vítreo/citologia
15.
Mod Pathol ; 19(9): 1213-20, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16729016

RESUMO

Both epidermal growth factor receptor (EGFR) and ErbB-2 play an important role in cancer biology and constitute promising molecular targets of therapy. EGFR and ErbB-2 expression has been observed in rhabdomyosarcoma cell lines but not analyzed systematically in rhabdomyosarcoma tumors. Tissue microarray sections representing 66 rhabdomyosarcoma tumors (34 embryonal rhabdomyosarcoma, 32 alveolar rhabdomyosarcoma) were surveyed by immunohistochemistry using antibodies specific for EGFR and ErbB-2. Immunostains were assessed for intensity (0: no immunostaining; 1: weak; 2: moderate; 3: strong) and percentage of at least 500 neoplastic cells exhibiting membranous or membranous and cytoplasmic immunostaining. EGFR and ErbB-2 expression was considered positive if the product of intensity and percentage was greater than 10. Patients had a median age of 5.7 years (range 8 months-19.1 years), and of 65/66 patients, 38 were males and 27 were females. Expression of ErbB-2 was identified in 22/66 (33%) cases and tended to be more frequent in the alveolar subtype (13/32, 41%, vs 9/34, 26%, P=0.30). Expression of EGFR was identified in 31/66 (47%) cases and correlated with the embryonal subtype (26/34, 76%, vs 5/32, 16%, P<0.0001) independent of stage, age, and gender. Coexpression of EGFR and ErbB-2 was identified in eight tumors, of which six were embryonal rhabdomyosarcoma. None of the cases exhibited EGFR or ErbB-2 gene amplification, as assessed using fluorescence in situ hybridization. Furthermore, analysis of 11 additional rhabdomyosarcoma tumors (six alveolar; five embryonal) revealed no evidence of mutations in EGFR exons 18, 19, 20, and 21. In summary, expression of EGFR and/or ErbB-2 is detected in a sizeable subset of rhabdomyosarcoma tumors without evidence of EGFR or ErbB-2 amplification or mutations in the EGFR tyrosine kinase domain. Notably, expression of EGFR correlates with the embryonal subtype, which is also more likely to coexpress EGFR and ErbB-2.


Assuntos
Receptores ErbB/metabolismo , Receptor ErbB-2/metabolismo , Rabdomiossarcoma Alveolar/metabolismo , Rabdomiossarcoma Embrionário/metabolismo , Neoplasias de Tecidos Moles/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Análise Mutacional de DNA , DNA de Neoplasias/análise , Receptores ErbB/genética , Feminino , Dosagem de Genes , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Lactente , Masculino , Receptor ErbB-2/genética , Rabdomiossarcoma Alveolar/genética , Rabdomiossarcoma Alveolar/patologia , Rabdomiossarcoma Embrionário/genética , Rabdomiossarcoma Embrionário/patologia , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia , Análise Serial de Tecidos
16.
Invest Ophthalmol Vis Sci ; 44(4): 1767-74, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12657620

RESUMO

PURPOSE: To investigate the alterations in gene expression when human retinal pigment epithelial (RPE) cells in culture are treated with vitreous as a model for the changes that occur in proliferative vitreoretinopathy. METHODS: Human RPE cells were cultured with or without human vitreous or collagen. RNA was extracted and reverse transcribed. The RNAs expressed were compared by using DNA macroarrays. Messenger RNA levels were also measured using real-time reverse transcription polymerase chain reaction. Protein expression was examined by immunoblot analysis. Immunoassays were used to determine levels of prostaglandin E(2). RESULTS: Vitreous treatment of RPE cells resulted in increased expression of two critical enzymes in the synthesis of prostaglandin E(2): membrane-associated prostaglandin E-synthase (mPGES) and cyclooxygenase (COX)-2. Increased levels of mPGES RNA and protein were still present at 48 hours of treatment, but the increase in COX-2 mRNA and protein was transient. The increase in the expression of mPGES was associated with an increase in the production of prostaglandin E(2) that was observed at 12 and 24 hours of treatment but not at 48 hours. Treatment with 100 microg collagen I per ml medium did not cause increased expression of mPGES and COX-2, even though both collagen- and vitreous-treatment caused a morphologic change in the RPE cells to a more fibroblast-like phenotype. CONCLUSIONS: Treatment of human RPE cells with vitreous induces changes in gene expression that are indicative of an inflammatory response.


Assuntos
Dinoprostona/biossíntese , Expressão Gênica/fisiologia , Oxirredutases Intramoleculares/genética , Isoenzimas/genética , Epitélio Pigmentado Ocular/metabolismo , Prostaglandina-Endoperóxido Sintases/genética , Corpo Vítreo/fisiologia , Células Cultivadas , Colágeno Tipo I/fisiologia , Ciclo-Oxigenase 2 , Humanos , Oxirredutases Intramoleculares/metabolismo , Isoenzimas/metabolismo , Proteínas de Membrana , Análise de Sequência com Séries de Oligonucleotídeos , Epitélio Pigmentado Ocular/citologia , Prostaglandina-E Sintases , Prostaglandina-Endoperóxido Sintases/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Exp Eye Res ; 74(1): 83-92, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11878821

RESUMO

The retina expresses metallothionein (MT) which has been reported to protect cells against oxidative stress and apoptosis. The types of MT expressed by human retinal cells were identified by laser capture microdissection and RT--PCR and it was found that MT-2a is expressed by retinal pigment epithelial (RPE) cells, photoreceptor cells, inner nuclear layer cells and ganglion cells while MT-1a is expressed by RPE cells and MT-3 by cells of the neural retina. MT is induced in cultured human RPE cells under stress conditions such as the presence of glucocorticoids, interleukin-1/TNF alpha, oxygen and TGF beta 1. Cultured human D407 RPE cells were transfected with plasmids that allowed the expression of MT to be controlled via the tet operator protein by the level of tetracycline in the medium. These experiments showed that elevation of MT levels by transfection of RPE cells protects them against toxic levels of cadmium, heme- and iron-induced oxidation and UV light-induced apoptosis.


Assuntos
Apoptose/fisiologia , Células Epiteliais/citologia , Metalotioneína/fisiologia , Estresse Oxidativo/fisiologia , Epitélio Pigmentado Ocular/citologia , Apoptose/efeitos da radiação , Células Cultivadas , Células Epiteliais/fisiologia , Regulação da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Metalotioneína/genética , Metalotioneína/metabolismo , Epitélio Pigmentado Ocular/fisiologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Raios Ultravioleta
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