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1.
Oncogene ; 41(10): 1456-1467, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35042959

RESUMO

In the tumor microenvironment, Cancer Associated Fibroblasts (CAFs) become activated by cancer cells and increase their secretory activity to produce soluble factors that contribute to tumor cells proliferation, invasion and dissemination to distant organs. The pro-tumorigenic transcription factor STAT3 and its canonical inducer, the pro-inflammatory cytokine IL-6, act conjunctly in a positive feedback loop that maintains high levels of IL-6 secretion and STAT3 activation in both tumor and stromal cells. Here, we demonstrate that STAT3 is essential for the pro-tumorigenic functions of murine breast cancer CAFs both in vitro and in vivo, and identify a STAT3 signature significantly enriched for genes encoding for secreted proteins. Among these, ANGPTL4, MMP13 and STC-1 were functionally validated as STAT3-dependent mediators of CAF pro-tumorigenic functions by different approaches. Both in vitro and in vivo CAFs activities were moreover impaired by MMP13 inhibition, supporting the feasibility of a therapeutic approach based on inhibiting STAT3-induced CAF-secreted proteins. The clinical potential of such an approach is supported by the observation that an equivalent CAF-STAT3 signature in humans is expressed at high levels in breast cancer stromal cells and characterizes patients with a shorter disease specific survival, including those with basal-like disease.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Proteína 4 Semelhante a Angiopoietina/genética , Animais , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Feminino , Fibroblastos/metabolismo , Glicoproteínas , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral/genética
2.
Adv Sci (Weinh) ; 9(9): e2103249, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35098698

RESUMO

Breast cancer is the most prevalent cancer and a major cause of death in women worldwide. Although early diagnosis and therapeutic intervention significantly improve patient survival rate, metastasis still accounts for most deaths. Here it is reported that, in a cohort of more than 2000 patients with breast cancer, overexpression of PI3KC2α occurs in 52% of cases and correlates with high tumor grade as well as increased probability of distant metastatic events, irrespective of the subtype. Mechanistically, it is demonstrated that PI3KC2α synthetizes a pool of PI(3,4)P2 at focal adhesions that lowers their stability and directs breast cancer cell migration, invasion, and metastasis. PI(3,4)P2 locally produced by PI3KC2α at focal adhesions recruits the Ras GTPase activating protein 3 (RASA3), which inactivates R-RAS, leading to increased focal adhesion turnover, migration, and invasion both in vitro and in vivo. Proof-of-concept is eventually provided that inhibiting PI3KC2α or lowering RASA3 activity at focal adhesions significantly reduces the metastatic burden in PI3KC2α-overexpressing breast cancer, thereby suggesting a novel strategy for anti-breast cancer therapy.


Assuntos
Neoplasias da Mama , Adesão Celular/fisiologia , Feminino , Adesões Focais/metabolismo , Adesões Focais/patologia , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Fosfatidilinositóis/metabolismo
3.
J Neurosurg Sci ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34763393

RESUMO

BACKGROUND: Medulloblastoma is a highly malignant, embryonal tumor, which is rare in adults, and shows distinct clinical, histopathological, molecular and treatment response features. METHODS: We retrospectively investigated 44 adults (age 17-48 years) with an histological diagnosis of medulloblastoma, and in 23 immunohistochemistry was used to identif y the molecular subgroups. We analyzed demographic, diagnostic, therapeutic and cognitive data, and correlated with PFS (progression-free-survival) and OS (overall survival). RESULTS: We observed a male prevalence and a median age of 31 years. Symptoms at onset were related to infratentorial location, while myeloradicular and/or cranial nerve involvement was rare. Histological examination showed the classic variant in 75% of patients, the desmoplastic/nodular in 23% and the anaplastic in one. As for molecular diagnosis, 17 patients were SHH and 6 non-WNT/non-SHH (5 group 4 and 1 group 3), while no WNT subgroup was found. The SHH subgroup had a prevalence of high-risk patients and leptomeningeal involvement. Patients underwent grosstotal or subtotal/partial resection, and craniospinal irradiation, followed in 20 cases by adjuvant chemotherapy. Median OS and PFS were 16.9 and 12 years, respectively. Metastatic disease at presentation and subtotal/partial resection were associated with worse prognosis, while the addition of chemotherapy did not yield a significant advantage over radiotherapy alone. Cognitive impairment in long-term survivors was limited and late relapses occurred in 15% of patients. CONCLUSIONS: Future studies with adequate sample size and long-term follow-up should prospectively investigate the role of surgery and adjuvant therapies across the different molecular subgroups to see whether a personalized approach is feasible.

4.
Oncoimmunology ; 7(3): e1408746, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29399412

RESUMO

Aggressive forms of breast cancer, such as Her2+ and triple negative breast cancer (TNBC), are enriched in breast cancer stem cells (BCSC) and have limited therapeutic options. BCSC represent a key cellular reservoir for relapse, metastatic progression and therapeutic resistance. Their ability to resist common cytotoxic therapies relies on different mechanisms, including improved detoxification. The cystine-glutamate antiporter protein xCT (SLC7A11) regulates cystine intake, conversion to cysteine and subsequent glutathione synthesis, protecting cells against oxidative and chemical insults. Our previous work showed that xCT is highly expressed in tumorspheres derived from breast cancer cell lines and downregulation of xCT altered BCSC function in vitro and inhibited pulmonary metastases in vivo. We further strengthened these observations by developing a virus-like-particle (VLP; AX09-0M6) immunotherapy targeting the xCT protein. AX09-0M6 elicited a strong antibody response against xCT including high levels of IgG2a antibody. IgG isolated from AX09-0M6 treated mice bound to tumorspheres, inhibited xCT function as assessed by reactive oxygen species generation and decreased BCSC growth and self-renewal. To assess if AX09-0M6 impacts BCSC in vivo seeding, Her2+ TUBO-derived tumorspheres were injected into the tail vein of AX09-0M6 or control treated female BALB/c mice. AX09-0M6 significantly inhibited formation of pulmonary nodules. To evaluate its ability to impact metastases, AX09-0M6 was administered to mice with established subcutaneous 4T1 tumors. AX09-0M6 administration significantly hampered tumor growth and development of pulmonary metastases. These data show that a VLP-based immunization approach inhibits xCT activity, impacts BCSC biology and significantly reduces metastatic progression in preclinical models.

5.
Oncotarget ; 8(6): 10007-10024, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28052020

RESUMO

Epithelial splicing regulatory protein 1 (ESRP1) is an epithelial cell-specific RNA binding protein that controls several key cellular processes, like alternative splicing and translation. Previous studies have demonstrated a tumor suppressor role for this protein. Recently, however, a pro-metastatic function of ESRP1 has been reported. We thus aimed at clarifying the role of ESRP1 in Colorectal Cancer (CRC) by performing loss- and gain-of-function studies, and evaluating tumorigenesis and malignancy with in vitro and in vivo approaches. We found that ESRP1 plays a role in anchorage-independent growth of CRC cells. ESRP1-overexpressing cells grown in suspension showed enhanced fibroblast growth factor receptor (FGFR1/2) signalling, Akt activation, and Snail upregulation. Moreover, ESRP1 promoted the ability of CRC cells to generate macrometastases in mice livers. High ESRP1 expression may thus stimulate growth of cancer epithelial cells and promote colorectal cancer progression. Our findings provide mechanistic insights into a previously unreported, pro-oncogenic role for ESRP1 in CRC, and suggest that fine-tuning the level of this RNA-binding protein could be relevant in modulating tumor growth in a subset of CRC patients.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Células CACO-2 , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Camundongos Endogâmicos NOD , Camundongos SCID , Micrometástase de Neoplasia , Fosfatidilinositol 3-Quinase/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Proteínas de Ligação a RNA/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail/metabolismo , Fatores de Tempo , Transfecção , Carga Tumoral
6.
Mol Cell Ther ; 3: 8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26464805

RESUMO

BACKGROUND: Medulloblastoma (MB) is the most common malignant childhood brain tumor with the propensity to disseminate at an early stage, and is associated with high morbidity. New treatment strategies are needed to improve cure rates and to reduce life-long cognitive and functional deficits associated with current therapies. Extracellular Vesicles (EVs) are important players in cell-to-cell communication in health and diseases. A clearer understanding of cell-to-cell communication in tumors can be achieved by studying EV secretion in medullospheres. This can reveal subtle modifications induced by the passage from adherent to non-adherent growth, as spheres may account for the adaptation of tumor cells to the mutated environment. METHODS: Formation of medullospheres from MB cell lines stabilized in adherent conditions was obtained through culture conditioning based on low attachment flasks and specialized medium. EVs collected by ultracentrifugation, in adherent conditions and as spheres, were subjected to electron microscopy, NanoSight measurements and proteomics. RESULTS: Interestingly, iron carrier proteins were only found in EVs shed by CSC-enriched tumor cell population of spheres. We used iron chelators when culturing MB cell lines as spheres. Iron chelators induced a decrease in number/size of spheres and in stem cell populations able to initiate in vitro spheres formation. CONCLUSIONS: This work suggests a not yet identified role of iron metabolism in MB progression and invasion and opens the possibility to use chelators as adjuvants in anti-tumoral chemotherapy.

7.
Antioxid Redox Signal ; 23(18): 1410-23, 2015 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-26067085

RESUMO

AIMS: The maintenance of heme homeostasis, mucosa cell renewal, and redox environment in the intestine is essential to permit digestion, absorption, cell proliferation, cell apoptosis, and immune response and to avoid the development of gut disorders. The feline leukemia virus, subgroup C, receptor 1a (FLVCR1a) is a heme exporter expressed in almost all cell types, including intestinal cells. This work investigates the role of FLVCR1a in the intestine, taking advantage of an intestine-specific conditional Flvcr1a-knockout mouse and of FLVCR1a-depleted Caco2 cells. RESULTS: The data show that FLVCR1a does not participate in the absorption of dietary heme, whereas it is involved in the export of de novo synthesized heme from intestinal cells. The loss of Flvcr1a is associated with a decrease of intestinal cell proliferation and with alterations in the peculiar homeostasis of proliferating cells, including the maintenance of their redox status. The involvement of FLVCR1a in these processes renders this exporter crucial for the survival of mice in a model of ulcerative colitis. INNOVATION: These findings shed light on the role of heme export in the dietary heme absorption process and unravel a new role for heme export in the control of mucosal renewal and in proliferating cell redox status and metabolic activity, demonstrating a crucial role for FLVCR1a in maintaining intestinal homeostasis in both physiologic and pathologic situations. CONCLUSION: By exporting the excess of de novo synthesized heme from intestinal cells, FLVCR1a participates in the control of intestinal mucosa homeostasis.


Assuntos
Heme/metabolismo , Mucosa Intestinal/metabolismo , Proteínas de Membrana Transportadoras/genética , Receptores Virais/genética , Animais , Células CACO-2 , Proliferação de Células , Técnicas de Inativação de Genes , Homeostase , Humanos , Intestinos/citologia , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores Virais/metabolismo
8.
Am J Cancer Res ; 4(5): 484-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25232490

RESUMO

Chronic inflammation is a well-recognized pathogenic factor in tumor initiation and progression. Mice lacking the pro-oncogenic transcription factor STAT3 were shown to be protected from both colitis-associated and epidermal cancers induced by the AOM/DSS and DMBA/TPA protocols, respectively. However, these murine models did not distinguish between the two STAT3 isoforms, the full-length STAT3α, believed to exert most pro-oncogenic functions attributed to STAT3, and the shorter STAT3ß, often referred to as a dominant-negative, but possessing specific transcriptional activities. Here we assessed the contribution of STAT3ß to inflammation-driven tumorigenesis making use of mice lacking this isoform, but still expressing STAT3α (STAT3(Δß/Δß)). We show that the lack of STAT3ß leads to exacerbated acute responses to both TPA and DSS, thus confirming its anti-inflammatory role. Enhanced inflammation correlates with earlier tumor onset in both the epidermis and the intestine in STAT3(Δß/Δß) mice. In contrast, overall tumor development and final tumor burden were unaffected. These results suggest that STAT3ß, by limiting inflammation during the initial phases of tumorigenesis, contributes to tissue homeostasis and counteracts malignant transformation and initial tumor growth. Accordingly, the balance between the two STAT3 isoforms, likely determined by the complex signaling networks shaping the tumor microenvironment and driving tumor transformation and progression, is apparently crucial to determine the initial tumor transformation rates in inflammation-associated cancers.

9.
Free Radic Biol Med ; 68: 134-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24291398

RESUMO

Loss-of-function mutations in the KRIT1 gene (CCM1) have been associated with the pathogenesis of cerebral cavernous malformations (CCM), a major cerebrovascular disease. However, KRIT1 functions and CCM pathogenetic mechanisms remain incompletely understood. Indeed, recent experiments in animal models have clearly demonstrated that the homozygous loss of KRIT1 is not sufficient to induce CCM lesions, suggesting that additional factors are necessary to cause CCM disease. Previously, we found that KRIT1 is involved in the maintenance of the intracellular reactive oxygen species (ROS) homeostasis to prevent ROS-induced cellular dysfunctions, including a reduced ability to maintain a quiescent state. Here, we show that KRIT1 loss of function leads to enhanced expression and phosphorylation of the redox-sensitive transcription factor c-Jun, as well as induction of its downstream target COX-2, in both cellular models and human CCM tissues. Furthermore, we demonstrate that c-Jun upregulation can be reversed by either KRIT1 re-expression or ROS scavenging, whereas KRIT1 overexpression prevents forced upregulation of c-Jun induced by oxidative stimuli. Taken together with the reported role of c-Jun in vascular dysfunctions triggered by oxidative stress, our findings shed new light on the molecular mechanisms underlying KRIT1 function and CCM pathogenesis.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Estresse Oxidativo/genética , Proteínas Proto-Oncogênicas/genética , Animais , Regulação da Expressão Gênica , Hemangioma Cavernoso do Sistema Nervoso Central/metabolismo , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteína KRIT1 , Mutação , Espécies Reativas de Oxigênio/metabolismo
10.
Histochem Cell Biol ; 140(6): 685-90, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24013649

RESUMO

A simple modification of the cell block technique for cultured cells grown in different conditions and suitable for the construction of tissue micro arrays (TMA) is described. The application of mechanical stirring during clot formation allows the uniform dispersion of cells in the fibrin mesh, thus increasing the final volume of the embedded material of evenly distributed cells. This technique is easily applied to spheres-obtained from cell lines cultured under appropriate conditions-that are enriched in stem cells. The possibility of constructing TMA using cell lines (grown in adherence and as spheres) and samples of the corresponding tumors or normal tissues may allow the direct comparison of original tumors with in vitro-expanded cell lines.


Assuntos
Técnicas de Cultura de Células/métodos , Neoplasias/patologia , Inclusão em Parafina , Análise Serial de Tecidos , Linhagem Celular Tumoral , Humanos , Imuno-Histoquímica , Células-Tronco Neoplásicas/citologia
11.
PLoS One ; 8(5): e63748, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717474

RESUMO

BACKGROUND: Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies. METHODOLOGY/PRINCIPAL FINDINGS: The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and ß-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression. CONCLUSIONS/SIGNIFICANCE: Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.


Assuntos
Meduloblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteômica , Biomarcadores , Linhagem Celular Tumoral , Movimento Celular , Humanos , Imunofenotipagem , Meduloblastoma/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/ultraestrutura , Fenótipo , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Proteoma , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Esferoides Celulares , Células Tumorais Cultivadas
12.
EMBO Mol Med ; 5(4): 572-90, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23460527

RESUMO

Myocarditis, often triggered by viral infection, may lead to heart auto-immunity and dilated cardiomyopathy. What determines the switch between disease resolution and progression is however incompletely understood. We show that pharmacological inhibition of STAT3, the main mediator of IL-6 signalling and of Th17-cell differentiation, protects mice from the development of Experimental Auto-immune Myocarditis reducing liver production of the complement component C3, and can act therapeutically when administered at disease peak. Further, we demonstrate that STAT3 is sufficient when constitutively active for triggering the onset of immune-mediated myocarditis, involving enhanced complement C3 production and IL-6 signalling amplification in the liver. Disease development can be prevented by C3 depletion and IL-6 receptor neutralization. This appears to be relevant to disease pathogenesis in humans, since acute myocarditis patients display significantly elevated circulating IL-6 and C3 levels and activated heart STAT3. Thus, aberrant IL-6/STAT3-mediated induction of liver acute phase response genes including C3, which occurs as a consequence of pre-existing inflammatory conditions, might represent an important factor determining the degree of myocarditis and its clinical outcome.


Assuntos
Cardiomiopatia Dilatada/imunologia , Miocardite/imunologia , Fator de Transcrição STAT3/imunologia , Animais , Linfócitos T CD4-Positivos/microbiologia , Cardiomiopatia Dilatada/genética , Complemento C3/imunologia , Progressão da Doença , Feminino , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Fígado/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Miocardite/genética , Fator de Transcrição STAT3/genética , Células Th17/imunologia
13.
FASEB J ; 27(3): 1223-35, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23233531

RESUMO

Breast cancer is often fatal during its metastatic dissemination. To unravel the role of microRNAs (miRs) during malignancy, we analyzed miR expression in 77 primary breast carcinomas and identified 16 relapse-associated miRs that correlate with survival and/or distinguish tumor subtypes in different datasets. Among them, miR-148b, down-regulated in aggressive breast tumors, was found to be a major coordinator of malignancy. In fact, it is able to oppose various steps of tumor progression when overexpressed in cell lines by influencing invasion, survival to anoikis, extravasation, lung metastasis formation, and chemotherapy response. miR-148b controls malignancy by coordinating a novel pathway involving over 130 genes and, in particular, it directly targets players of the integrin signaling, such as ITGA5, ROCK1, PIK3CA/p110α, and NRAS, as well as CSF1, a growth factor for stroma cells. Our findings reveal the importance of the identified 16 miRs for disease outcome predictions and suggest a critical role for miR-148b in the control of breast cancer progression.


Assuntos
Neoplasias da Mama/metabolismo , Integrina alfa5/biossíntese , Fator Estimulador de Colônias de Macrófagos/biossíntese , MicroRNAs/metabolismo , Proteína Oncogênica p21(ras)/biossíntese , Fosfatidilinositol 3-Quinases/biossíntese , RNA Neoplásico/metabolismo , Quinases Associadas a rho/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases , Progressão da Doença , Feminino , Humanos , Integrina alfa5/genética , Fator Estimulador de Colônias de Macrófagos/genética , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteína Oncogênica p21(ras)/genética , Fosfatidilinositol 3-Quinases/genética , RNA Neoplásico/genética , Quinases Associadas a rho/genética
14.
Environ Health ; 11: 59, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22947094

RESUMO

BACKGROUND: Formaldehyde (HCHO) is a gas (available as a 37% concentrated solution, stabilized with methanol). The 10% dilution (approximately 4% formaldehyde) has been used as a fixative since the end of the 19th century. Alternative fixatives are also commercially available or may be prepared in-house in laboratories. Statements by the IARC, along with other USA agencies (CalEPA, RoC/NTP) on the carcinogenicity of formaldehyde for humans renders its substitution in Pathology Departments necessary since the annual use of formalin may exceed 3,500 liters for a medium-large laboratory. To achieve a "formalin-free laboratory" we tested straightforward-to-make fixatives along with registered reagents offered as formalin substitutes. METHODS: More than two hundreds specimens were fixed in parallel with in-laboratory made fixatives PAGA (Polyethylenglycol, ethyl Alcohol, Glycerol, Acetic acid), two zinc-based fixatives (ZBF, Z7), and commercially-available alternatives (RCL2 and CellBlock). Tissue micro arrays were used for morphological and immunohistochemical comparison. Extraction of RNA was carried out to evaluate preservation of nucleic acids. RESULTS: Differences compared to formalin fixation were evident in alcohol-based fixatives, mainly restricted to higher stain affinity and considerable tissue shrinkage. Conversely, nuclear detail was superior with these alcohol-based formulas compared to formalin or glyoxale-based recipes. RNA extraction was superior for Z7, PAGA and RCL2 with regard to concentration but relatively comparable regarding quality. CONCLUSIONS: Abolition of the human carcinogen formaldehyde from pathology laboratories is possible even in contexts whereby commercial alternatives to formalin are unavailable or are too expensive for routine use, and aspiration devices are lacking or not adequately serviced. The use of known formulations, possibly with simple and not-noxious ("alimentary grade") constituents, comparable with registered proprietary products, may expand the search for the ideal fixative combining satisfactory morphology with improved preservation of nucleic acids and proteins as well as being easy and safe to dispose of.


Assuntos
Fixadores , Fixação de Tecidos/métodos , Poluentes Atmosféricos , Poluição do Ar/prevenção & controle , Carcinógenos , Formaldeído , Laboratórios
15.
J Clin Oncol ; 30(26): 3187-93, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22851561

RESUMO

PURPOSE: To compare event-free survival (EFS), overall survival (OS), pattern of relapse, and hearing loss in children with standard-risk medulloblastoma treated by postoperative hyperfractionated or conventionally fractionated radiotherapy followed by maintenance chemotherapy. PATIENTS AND METHODS: In all, 340 children age 4 to 21 years from 122 European centers were postoperatively staged and randomly assigned to treatment with hyperfractionated radiotherapy (HFRT) or standard (conventional) fractionated radiotherapy (STRT) followed by a common chemotherapy regimen consisting of eight cycles of cisplatin, lomustine, and vincristine. RESULTS: After a median follow-up of 4.8 years (range, 0.1 to 8.3 years), survival rates were not significantly different between the two treatment arms: 5-year EFS was 77% ± 4% in the STRT group and 78% ± 4% in the HFRT group; corresponding 5-year OS was 87% ± 3% and 85% ± 3%, respectively. A postoperative residual tumor of more than 1.5 cm(2) was the strongest negative prognostic factor. EFS of children with all reference assessments and no large residual tumor was 82% ± 2% at 5 years. Patients with a delay of more than 7 weeks to the start of RT had a worse prognosis. Severe hearing loss was not significantly different for the two treatment arms at follow-up. CONCLUSION: In this large randomized European study, which enrolled patients with standard-risk medulloblastoma from more than 100 centers, excellent survival rates were achieved in patients without a large postoperative residual tumor and without RT treatment delays. EFS and OS for HFRT was not superior to STRT, which therefore remains standard of care in this disease.


Assuntos
Neoplasias Cerebelares/radioterapia , Fracionamento da Dose de Radiação , Meduloblastoma/radioterapia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Criança , Pré-Escolar , Terapia Combinada , Irradiação Craniana , Intervalo Livre de Doença , Feminino , Perda Auditiva/etiologia , Humanos , Masculino , Radioterapia Adjuvante , Recidiva , Taxa de Sobrevida
16.
PLoS One ; 6(12): e28175, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22194812

RESUMO

BACKGROUND: Regarding regenerative medicine for diabetes, accessible sources of Mesenchymal Stem Cells (MSCs) for induction of insular beta cell differentiation may be as important as mastering the differentiation process itself. METHODOLOGY/PRINCIPAL FINDINGS: In the present work, stem cells from pancreatic islets (human islet-mesenchymal stem cells, HI-MSCs) and from human bone marrow (bone marrow mesenchymal stem cells, BM-MSCs) were cultured in custom-made serum-free medium, using suitable conditions in order to induce differentiation into Islet-like Cells (ILCs). HI-MSCs and BM-MSCs were positive for the MSC markers CD105, CD73, CD90, CD29. Following this induction, HI-MSC and BM-MSC formed evident islet-like structures in the culture flasks. To investigate functional modifications after induction to ILCs, ultrastructural analysis and immunofluorescence were performed. PDX1 (pancreatic duodenal homeobox gene-1), insulin, C peptide and Glut-2 were detected in HI-ILCs whereas BM-ILCs only expressed Glut-2 and insulin. Insulin was also detected in the culture medium following glucose stimulation, confirming an initial differentiation that resulted in glucose-sensitive endocrine secretion. In order to identify proteins that were modified following differentiation from basal MSC (HI-MSCs and BM-MSCs) to their HI-ILCs and BM-ILCs counterparts, proteomic analysis was performed. Three new proteins (APOA1, ATL2 and SODM) were present in both ILC types, while other detected proteins were verified to be unique to the single individual differentiated cells lines. Hierarchical analysis underscored the limited similarities between HI-MSCs and BM-MSCs after induction of differentiation, and the persistence of relevant differences related to cells of different origin. CONCLUSIONS/SIGNIFICANCE: Proteomic analysis highlighted differences in the MSCs according to site of origin, reflecting spontaneous differentiation and commitment. A more detailed understanding of protein assets may provide insights required to master the differentiation process of HI-MSCs to functional beta cells based only upon culture conditioning. These findings may open new strategies for the clinical use of BM-MSCs in diabetes.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular , Ilhotas Pancreáticas/citologia , Células-Tronco Mesenquimais/ultraestrutura , Western Blotting , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/ultraestrutura , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Separação Celular , Forma Celular/efeitos dos fármacos , Análise por Conglomerados , Meios de Cultura/farmacologia , Eletroforese em Gel Bidimensional , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Insulina/metabolismo , Secreção de Insulina , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Fenótipo , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
17.
Childs Nerv Syst ; 27(12): 2077-85, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21717155

RESUMO

OBJECTIVE: The purpose of this study is to detect different protein profiles in medulloblastoma (MDB) that may be clinically relevant and to check the correspondence of histological classification of MDB with proteomic profiles. MATERIALS AND METHODS: Surgical specimens, snap frozen at the time of neurosurgery, entered the proteomic study. Eight samples from patients (age range, 4 months-26 years) with different MDB histotypes (five classic, one desmoplastic/nodular, one with extensive nodularity, and one anaplastic) were analyzed by two-dimensional gel electrophoresis. One sample for each histotype was further characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis. RESULTS: Eighty-six unique proteins were identified and compared to histology, with the determination of proteins expressed by single histotypes and of a smaller number of proteins shared by two or three histotypes. The sharp difference of protein expression was found to be in agreement with WHO histological classification, with the identification of type-specific proteins with limited overlapping between histotypes. CONCLUSION: Proteomic analysis confirmed and strengthened the difference between histotypes as biologically relevant. Cluster analysis enhanced the distance of extensive nodularity MDB from other histotypes. Possible innovative approaches to therapy may rely upon a proteomic-based classification of MDB tightly correlated to histology. The utility of snap freezing tumoral samples must be stressed and should become a mandatory task for pathologists.


Assuntos
Neoplasias Cerebelares/metabolismo , Eletroforese em Gel Bidimensional/métodos , Meduloblastoma/metabolismo , Proteínas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adolescente , Adulto , Neoplasias Cerebelares/classificação , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Humanos , Lactente , Masculino , Meduloblastoma/classificação , Peroxirredoxinas/análise , Peroxirredoxinas/metabolismo , Proteômica , Estatmina/análise , Estatmina/metabolismo , Adulto Jovem
18.
Eur J Cancer ; 47(2): 287-95, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20932739

RESUMO

BACKGROUND: Epithelioid sarcoma (ES) is a rare soft tissue neoplasm that usually arises in the distal extremities of young adults, presents a high rate of recurrences and metastases and frequently poses diagnostic dilemmas. In order to identify markers useful for patient stratification purposes, we investigated the prognostic impact of clinical and molecular patient characteristics, including the status of SMARCB1 tumour suppressor gene, in a consecutive series of ES cases. METHODS: Kaplan-Meier survival curves were compared by the log-rank test. Immunophenotyping and SMARCB1 protein expression were analysed by immunohistochemistry or western blotting in 40 ES patients for which tumour material was available. Cases lacking SMARCB1 protein expression were investigated for the presence of gene mutations and gene deletions by exon sequencing, fluorescent in situ hybridization and quantitative PCR. RESULTS: FNCLCC tumour grade 3 and proximal-type histology significantly correlated with shorter overall survival (log-rank p=0.0046 and p=0.0001, respectively). We identified loss of SMARCB1 protein expression in the majority of ES cases (25/40, 62.5%), including 24/34 (71%) adult cases but only 1/6 (17%) paediatric/adolescent cases (p=0.02, two-tailed Fisher's exact test). The absence of protein is strongly correlated with SMARCB1 gene deletion (p=0.003, two-tailed Fisher's exact test). We observed a trend towards the correlation between SMARCB1 inactivation and both higher tumour grading and a clinical course of the disease characterised by the occurrence of multiple relapses/metastasis. CONCLUSION: These data show that both tumour grading and subtype are prognostic factors in ES. Loss of SMARCB1 protein expression in ES is a frequent occurrence mediated by gene deletion events, thus pointing to a crucial role of SMARCB1 in ES genesis. Analysis of SMARCB1 status in ES warrants prospective investigation as a prognostic marker and therapeutic target.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Tumores do Estroma Gastrointestinal/mortalidade , Tumor Rabdoide/mortalidade , Sarcoma/mortalidade , Fatores de Transcrição/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/genética , Criança , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/genética , Extremidades , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Genes Supressores de Tumor , Humanos , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Mutação/genética , Prognóstico , Tumor Rabdoide/genética , Tumor Rabdoide/patologia , Proteína SMARCB1 , Sarcoma/genética , Sarcoma/patologia , Fatores de Transcrição/genética , Células Tumorais Cultivadas , Adulto Jovem
19.
Brain Pathol ; 21(2): 215-24, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21029238

RESUMO

Cerebral cavernous malformations (CCMs) are vascular lesions of the CNS characterized by abnormally enlarged capillary cavities. CCMs can occur as sporadic or familial autosomal dominant form. Familial cases are associated with mutations in CCM1[K-Rev interaction trapped 1 (KRIT1)], CCM2 (MGC4607) and CCM3 (PDCD10) genes. In this study, a three-gene mutation screening was performed by direct exon sequencing, in a cohort of 95 Italian patients either sporadic or familial, as well as on their at-risk relatives. Sixteen mutations in 16 unrelated CCM patients were identified,nine mutations are novel: c.413T > C; c.601C > T; c.846 + 2T > G; c.1254delA; c.1255-4delGTA; c.1682-1683 delTA in CCM1; c.48A > G; c.82-83dupAG in CCM2; and c.395 + 1G > A in CCM3 genes [corrected].The samples, negative to direct exon sequencing, were investigated by MLPA to search for intragenic deletions or duplications. One deletion in CCM1 exon 18 was detected in a sporadic patient. Among familial cases 67% had a mutation in CCM1, 5.5% in CCM2, and 5.5% in CCM3, whereas in the remaining 22% no mutations were detected, suggesting the existence of either undetectable mutations or other CCM genes. This study represents the first extensive research program for a comprehensive molecular screening of the three known genes in an Italian cohort of CCM patients and their at-risk relatives.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas de Transporte/genética , Malformações Vasculares do Sistema Nervoso Central/genética , Predisposição Genética para Doença/genética , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas Proto-Oncogênicas/genética , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Humanos , Itália , Proteína KRIT1 , Masculino , Linhagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Eur Radiol ; 20(11): 2740-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20582701

RESUMO

OBJECTIVE: Percutaneous biopsies are gaining acceptance in the diagnosis of soft-tissue tumours. Sampling in the most representative area is not easy in sarcomas of huge dimension. We hypothesised that ultrasound (US) contrast medium could identify the representative area for focus core-needle biopsy (CNB) METHODS: This is a retrospective cohort series of 115 soft-tissue masses treated from January 2007 to November 2008. Accuracy of US-guided CNB after contrast-enhanced US (CEUS) was determined by comparing the histology of the biopsy with the definitive diagnosis in 105 surgically excised samples (42 benign, 63 malignant) and with the expected outcome in the remaining ten malignant cases not surgically treated. A myxoid component was present in 21 sarcomas (34.4%). RESULTS: Of samples, 94.8% were adequate for diagnosis with 97.1% sensitivity and 92.5% specificity. Sensitivity and specificity in specific histopathological subgroupings were 100%, and in grading definition they were 100% and 96.8%. DISCUSSION: US-guided CNB is safe and effective. US contrast medium depicts tumour vascular supply and identifies the representative area(s) for sampling. Sensitivity and specificity are also high in subgrouping and grading, including myxoid types. Discussion about biopsy is part of the essential multidisciplinary strategy for these tumours.


Assuntos
Biópsia por Agulha , Meios de Contraste , Fosfolipídeos , Neoplasias de Tecidos Moles/patologia , Hexafluoreto de Enxofre , Ultrassonografia de Intervenção , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sarcoma/diagnóstico por imagem , Sarcoma/patologia , Sensibilidade e Especificidade , Neoplasias de Tecidos Moles/diagnóstico por imagem , Adulto Jovem
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