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1.
Int J Mol Sci ; 24(21)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37958708

RESUMO

Loco-regional chemotherapy is a strategy used to achieve more precise anticancer drug effect directly on tumor mass, while decreasing whole body exposure, which can lead to undesirable side effects. Thus, the loco-regional chemotherapy is conceptually similar to the targeted drug delivery systems for delivering chemotherapeutics to cancer cells in a certain location of the body. Recently, it has been demonstrated that a novel polymeric film containing the complex between cisplatin (cisPt) and hyaluronan (sodium salt of hyaluronic acid; NaHA) enhanced in vivo efficacy and safety of cisplatin (cisPt) by loco-regional delivery in pleural mesothelioma. Biologically, hyaluronic acid (HA) binds with the CD44 receptor, which is a transmembrane glycoprotein overexpressed by other cancer cells. Thus, administering both cisPt and hyaluronan together as a complex loco-regionally to the tumor site could target cancer cells locally and enhance treatment safety. A slight excess of hyaluronan was required to have more than 85% cisPt complexation. In cell monolayers (2D model) the cisPt/NaHA complex in solution demonstrated dose- and time-dependent cytotoxic effect by decreasing the viability of pancreatic, melanoma, and lung cell lines (they all express CD44). At the same concentration in solution, the complex was as effective as cisPt alone. However, when applied as film to melanoma spheroids (3D model), the complex was superior because it prevented the tumor spheroid growth and, more importantly, the formation of new cell colonies. Hence, cisPt/NaHA complex could work in preventing metastases loco-regionally and potentially avoiding systemic relapses.


Assuntos
Antineoplásicos , Melanoma , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Ácido Hialurônico/metabolismo , Linhagem Celular Tumoral , Recidiva Local de Neoplasia/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Melanoma/tratamento farmacológico , Receptores de Hialuronatos/metabolismo
2.
Int J Pharm ; 622: 121848, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35613653

RESUMO

This study aimed at the development of hyaluronic acid-functionalised imatinib mesylate cubosomes (HA-IM-CBs) that might be useful in CD44 targeting against hepatic cancer. The HA-IM-CBs had a 130.7 ±â€¯2.92 nm particle size, -31.40 ±â€¯2.76 mV zeta potential, and 76.14 ±â€¯2.69% release. The architecture of HA-IM-CBs was confirmed using HR-TEM and AFM. When compared to plain IM and IM-CBs, in vitro experiments revealed that HA-IM-CBs outperformed by significantly reducing cell viability. DAPI staining and ROS corroborated the apoptotic effects. Biodistribution and Pharmacokinetics studies showedthat HA-IM-CBs exhibit a higher drug concentration in tumour tissue and better pharmacokinetic activity. This is the first study to show that HA-IM-CBs had CD44 targeting activity against HCC. CD44 regulates apoptosis via Bcl-2 family proteins and caspases, which interact with HA. Higher levels of e-NOS, BAD, BAX, and Cyt C and lower expressions of Bcl-xl, i-NOS, and Bcl-2 demonstrated the anti-HCC potential of HA-IM-CBs in qrt-PCR investigations. The remarkable therapeutic potential of HA-IM-CBs began with substantial stimulation of CD44 regulated caspase-mediated mitochondrial apoptotic pathway, accountable for their anti-HCC activity. The perturbed metabolites are restored to acceptable levels as indicated by metabolomic studies (1H NMR). Interestingly, the antineoplastic effect of HA-IM-CBs was proven to be potentially valuable against HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/química , Mesilato de Imatinib/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-bcl-2 , Distribuição Tecidual
3.
Arch Gynecol Obstet ; 306(4): 1147-1160, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35435483

RESUMO

PURPOSE: This meta-analysis investigated the relationships between the CD44+/CD24- phenotype and tumor size, lymph node metastasis, distant metastasis, disease-free survival (DFS), and overall survival (OS) in 8036 postoperative breast cancer patients enrolled in 23 studies. METHODS: A literature search of PubMed, Medline, Cochrane, Embase, and PMC was conducted to identify eligible studies. The combined odds ratios (ORs) and 95% confidence intervals (95% CIs) were analyzed to evaluate the relationships between the CD44+/CD24- phenotype and the pathological and biological characteristics of breast cancer patients, and the combined hazard ratios (HRs) and 95% CIs were calculated to evaluate the relationships between CD44+/CD24- and DFS and OS of breast cancer patients using Stata12.0 software. RESULTS: The CD44+/CD24- phenotype were not related to the tumor size (tumor size > 2.0 vs ≤ 2.0 cm, combined OR = 0.98, 95% CI 0.68-1.34, p = 0.792) and did not promote lymph node metastasis (lymph node metastasis vs. no lymph node metastasis, OR = 0.92, 95% CI 0.67-1.27, p = 0.626) and distant metastasis (distant metastasis vs no distant metastasis, combined OR = 3.88, 95% CI 0.93-16.24, p = 0.064). The CD44+/CD24- phenotype was negatively correlated with postoperative DFS (HR = 1.67, 95% CI 1.35-2.07, p < 0.00001) and OS (combined HR = 1.52, 95% CI 1.21-1.91, p = 0.0004). CONCLUSION: These results suggested expression of the CD44+/CD24- phenotype cannot be used as a reliable indicator of the tumor size, lymph node metastasis, and distant metastasis, however, it can be used be a potential therapeutic targets of DFS, OS in breast cancer patients.


Assuntos
Antígeno CD24 , Receptores de Hialuronatos , Biomarcadores Tumorais/metabolismo , Antígeno CD24/genética , Antígeno CD24/metabolismo , Intervalo Livre de Doença , Humanos , Receptores de Hialuronatos/metabolismo , Metástase Linfática , Prognóstico , Modelos de Riscos Proporcionais
4.
Virchows Arch ; 475(3): 349-356, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300876

RESUMO

The Cancer Genome Atlas project introduced genomic taxonomy of basal and luminal molecular subtypes in muscle invasive bladder cancer. Fewer studies have addressed the molecular classification in non-muscle invasive bladder cancer (NMIBC). Our aim is to assess the applicability of the proposed phenotypic classification for NMIBC. Three TMAs were constructed from 193 TURBT specimens of 60 bladder cancer patients treated at one of the authors' institutions (1998-2008). Follow-up data on recurrence, grade, or stage progression was obtained. Immunohistochemistry was performed using an automated Ventana System for markers indicative of luminal (GATA3, CK20, ER, Uroplakin II, and HER2/neu) and basal (CK5/6 and CD44) phenotype. Marker expression was evaluated by 3 urologic pathologists. Using unadjusted logistic regression, we found significant association between tumor recurrence at next biopsy and CD44 expression (OR = 2.51, P = 0.03), tumor recurrence at any subsequent biopsy and ER expression (OR = 0.24, P = 0.04), and tumor grade progression at any subsequent biopsy and HER2/neu expression (OR = 0.24, P = 0.04). After adjusting for pathologic stage, we found a significant association between CK5/6 expression and tumor stage progression at either next or any subsequent biopsy (OR = 0.94, P = 0.006; and OR = 0.97, P = 0.02, respectively). Our findings suggest that individual immunohistochemical markers may be of value as prognostic factors in NMIBC.


Assuntos
Neoplasias da Bexiga Urinária/classificação , Neoplasias da Bexiga Urinária/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma in Situ/patologia , Carcinoma de Células de Transição/patologia , Feminino , Fator de Transcrição GATA3/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica/métodos , Queratina-5/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Bexiga Urinária/metabolismo , Urotélio/patologia
5.
Arch Toxicol ; 92(4): 1495-1505, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29380012

RESUMO

Allergic contact dermatitis is a widespread health disorder and occupational skin disease. Hence, screening for contact-sensitizing chemicals is highly relevant to toxicology, dermatology, and occupational medicine. The use of animal tests for this purpose is constrained by ethical considerations, need for high-throughput screening, and legislation (e.g., for cosmetics in the European Union). T cell activation is the final and most specific key event of the "adverse outcome pathway" for skin sensitization and therefore a promising target for the development of in vitro sensitization assays. We present a novel in vitro sensitization assay with a lymphocyte endpoint as an add-on to the loose-fit coculture-based sensitization assay (LCSA): the LCSA-ly. While the LCSA measures dendritic cell activation, the LCSA-ly offers the option for an additional lymphocyte endpoint which can be measured concurrently. We incorporated lymphocytes in our previously established coculture of primary human keratinocytes and monocyte-derived dendritic cells and tested nine substances: five sensitizers [2,4-dinitrochlorobenzene (DNCB) 1.25-15 µmol/l, p-phenylenediamine (PPD) 15.6-125 µmol/l, 2-mercaptobenzothiazole (MBT) 50-1000 µmol/l, coumarin, and resorcinol (both: 250-1500 µmol/l)] and four non-sensitizers (monochlorobenzene, caprylic acid, glycerol, and salicylic acid (all: 125-1000 µmol/l)]. DNCB and MBT increased a subset of IL-23 receptor+/IFN-γ receptor 1 (CD119)+ lymphocytes. DNCB, PPD, and MBT enhanced a subunit of the IL-4 receptor (CD124) and a memory marker (CD44) on lymphocytes. Remarkably, DNCB, PPD, and MBT raised IL-4 concentrations in coculture supernatants while IFN-γ levels decreased, which might point to Th2 activation in vitro. Coumarin, resorcinol, and non-sensitizers did not alter any of the tested surface markers or cytokines. IL-17 was not affected by any of the substances. Relative strength of sensitizers according to lymphocyte markers was DNCB > PPD > MBT, which corresponds to earlier results from the LCSA without lymphocyte endpoint, the murine local lymph node assay, and human data. This study is the first to prove the suitability of lymphocyte surface markers for sensitization testing and potency assessment.


Assuntos
Alérgenos/imunologia , Antígenos de Superfície/metabolismo , Citocinas/metabolismo , Dermatite Alérgica de Contato/imunologia , Alérgenos/toxicidade , Bioensaio , Técnicas de Cocultura , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Humanos , Receptores de Hialuronatos/metabolismo , Imunização , Subunidade alfa de Receptor de Interleucina-4/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Linfócitos/imunologia , Receptores de Interferon/metabolismo , Pele/efeitos dos fármacos , Pele/imunologia , Receptor de Interferon gama
6.
Stem Cell Rev Rep ; 12(4): 492-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27207017

RESUMO

Colorectal cancers (CRCs) form a disorganized hierarchy of heterogeneous cell populations on which current chemotherapy regimens fail to exert their distinctive cytotoxicity. A small sub-population of poorly differentiated cancer stem-like cells (CSCs), also known as cancer initiating cells, may exhibit embryonic and/or adult stem-cell gene expression signatures. Self-renewal and survival signals are also dominant over differentiation in CSCs. However, inducers of differentiation exclusive to CSC may affect cellular pathways required for the formation and progression of a tumor, which are not utilized in normal adult stem-cells. Nevertheless, assays for targeting CSCs have been hindered by expanding and maintaining rare CSCs in vitro. However, CRC-CSCs are able to form floating spheroids (known as colonospheres) 3-dimentinionally (3D) in a serum-free defined medium. Therefore, great efforts have been paid to improve colonosphere forming assay as a preclinical model to study tumor biology and to conduct drug screening in cancer research. The 3D-colonosphere culture model may also represent in vivo conditions for the spontaneous aggregation of cancer cells in spheroids. This protocol describes the development of an enrichment/culture assay using CRC-CSCs to facilitate colorectal cancer research through immunofluorescence staining of colonospheres. We have developed colonospheres from HCT116 CRC cell line to compare and link CRC-CSC markers to the NANOG expression level using an immunofluorescence assay. Our data also show that the immunostaining assay of colonosphere is a useful method to explore the role and dynamics of CRC-CSCs division between self-renewal and cell lineage differentiation of cancer cells. In principle, this method is applicable to a variety of primary cells and cell lines of epithelial origin. Furthermore, this protocol may also allow screening of libraries of compounds to identify bona fide CRC-CSC differentiation inducers.


Assuntos
Diferenciação Celular , Proliferação de Células , Células-Tronco Neoplásicas/metabolismo , Esferoides Celulares/metabolismo , Western Blotting , Autorrenovação Celular , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HCT116 , Humanos , Receptores de Hialuronatos/metabolismo , Microscopia de Fluorescência , Mucina-2/metabolismo , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/patologia , Esferoides Celulares/patologia
7.
PLoS One ; 9(10): e111375, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25354343

RESUMO

Human urinary disorders are generally studied in rodent models due to limitations of functional in vitro culture models of primary human urothelial cells (HUCs). Current HUC culture models are often derived from immortalized cancer cell lines, which likely have functional characteristics differ from healthy human urothelium. Here, we described a simple explant culture technique to generate HUCs and assessed their in vitro functions. Using transmission electron microscopy, we assessed morphology and heterogeneity of the generated HUCs and characterized their intercellular membrane structural proteins relative to ex vivo urothelium tissue. We demonstrated that our cultured HUCs are free of fibroblasts. They are also heterogeneous, containing cells characteristic of both immature basal cells and mature superficial urothelial cells. The cultured HUCs expressed muscarinic receptors (MR1 and MR2), carnitine acetyltransferase (CarAT), immunoregulatory cytokines IL7, IL15, and IL23, as well as the chemokine CCL20. HUCs also expressed epithelial cell-specific molecules essential for forming intercellular structures that maintain the functional capacity to form the physiological barrier of the human bladder urothelium. A subset of HUCs, identified by the high expression of CD44, expressed the Toll-like receptor 4 (TLR4) along with its co-receptor CD14. We demonstrated that HUCs express, at the mRNA level, both forms of the IL22 receptor, the membrane-associated (IL22RA1) and the secreted soluble (IL22RA2) forms; in turn, IL22 inhibited expression of MR1 and induced expression of CarAT and two antimicrobial peptides (S100A9 and lipocalin-2). While the cellular sources of IL22 have yet to be identified, the HUC cytokine and chemokine profiles support the concept that IL22-producing cells are present in the human bladder mucosa tissue and that IL22 plays a regulatory role in HUC functions. Thus, the described explant technique is clearly capable of generating functional HUCs suitable for the study of human urinary tract disorders, including interactions between urothelium and IL22-producing cells.


Assuntos
Acetilcolina/metabolismo , Calgranulina B/metabolismo , Interleucinas/farmacologia , Lipocalinas/metabolismo , Urotélio/metabolismo , Calgranulina B/genética , Células Cultivadas , Quimiocina CCL20/genética , Quimiocina CCL20/metabolismo , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Lipocalinas/genética , Receptores de Lipopolissacarídeos/genética , Receptores de Lipopolissacarídeos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Urotélio/efeitos dos fármacos , Urotélio/ultraestrutura , Interleucina 22
8.
Methods ; 67(1): 45-54, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23973811

RESUMO

Gene expression studies commonly examine total cellular RNA, which only provides information about its steady-state pool of RNA. It remains unclear whether differences in the steady-state reflects variable rates of transcription or RNA degradation. To specifically monitor RNA synthesis and degradation genome-wide, we developed Bru-Seq and BruChase-Seq. These assays are based on metabolic pulse-chase labeling of RNA using bromouridine (Bru). In Bru-Seq, recently labeled RNAs are sequenced to reveal spans of nascent transcription in the genome. In BruChase-Seq, cells are chased in uridine for different periods of time following Bru-labeling, allowing for the isolation of RNA populations of specific ages. Here we describe these methodologies in detail and highlight their usefulness in assessing RNA synthesis and stability as well as splicing kinetics with examples of specific genes from different human cell lines.


Assuntos
RNA Mensageiro/biossíntese , Uridina/análogos & derivados , Animais , Bromouracila/análogos & derivados , Códon sem Sentido , DNA Complementar/genética , Mutação da Fase de Leitura , Genoma Humano , Células HeLa , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Células K562 , Cinética , Anotação de Sequência Molecular , Splicing de RNA , Estabilidade de RNA , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Análise de Sequência de RNA , Coloração e Rotulagem , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Uridina/química
9.
J Thorac Oncol ; 8(11): 1389-95, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24084442

RESUMO

INTRODUCTION: Malignant pleural mesothelioma (MPM) is a highly aggressive neoplasm associated with asbestos exposure. Currently, the molecular mechanisms that induce MPM development are still unknown. The purpose of this study was to identify new molecular biomarkers for mesothelial carcinogenesis. METHODS: We analyzed a panel of 84 genes involved in extracellular matrix remodeling and cell adhesion by polymerase chain reaction (PCR) array in 15 samples of epithelioid mesothelioma and 10 samples of reactive mesothelial hyperplasia (MH; 3 of 25 samples were inadequate for mRNA analysis). To validate the differentially expressed genes identified by PCR array, we analyzed 27 more samples by immunohistochemistry, in addition to the 25 samples already studied. RESULTS: Twenty-five genes were differentially expressed in MPM and MH by PCR array. Of these we studied matrix metalloproteinase 7 (MMP7), MMP14, CD44, and integrin, alpha3 expression by immunohistochemistry in 26 epithelioid MPM and 26 MH samples from the entire series of 52 cases. We observed higher MMP14 and integrin, alpha3 expression in MPM samples compared with MH samples (p = 0.000002 and p = 0.000002, respectively). Conversely, CD44 expression was low in most (57.7%) mesothelioma samples but only in 11.5% of the MH samples (p = 0.0013). As regards MMP7, we did not observe differential expression between MH and MPM samples. CONCLUSIONS: We have extensively studied genes involved in cell adhesion and extracellular matrix remodeling in MPM and MH samples, gaining new insight into the pathophysiology of mesothelioma. Moreover, our data suggest that these factors could be potential biomarkers for MPM.


Assuntos
Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/metabolismo , Matriz Extracelular/metabolismo , Hiperplasia/metabolismo , Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , Neoplasias Pleurais/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Moléculas de Adesão Celular/genética , Matriz Extracelular/genética , Matriz Extracelular/patologia , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Hiperplasia/genética , Hiperplasia/patologia , Técnicas Imunoenzimáticas , Integrina alfa3/genética , Integrina alfa3/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , Mesotelioma/genética , Mesotelioma/patologia , Mesotelioma Maligno , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pleurais/genética , Neoplasias Pleurais/patologia , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
10.
Tumour Biol ; 33(4): 1215-22, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22392500

RESUMO

Eight of 15 human ovarian carcinoma cell lines were shown to express high levels of hyaluronan (HA) on their surfaces. The role of cell surface HA in its adhesion to mesothelial cells, which is potentially involved in peritoneal dissemination, was evaluated. Three human ovarian carcinoma cell lines, ES-2, MH, and KF cells, were repeatedly sorted into variant cell lines with high levels of cell surface HA (ES-2/HA+7, MH/HA+7, and KF/HA+7) and with low cell surface HA (ES-2/HA-7, MH/HA-7, and KF/HA-7). The ability of these cells to adhere to peritoneal mesothelial cells was compared. ES-2/HA+7, MH/HA+7, and KF/HA+7 cells were less adherent to mesothelial cells than the ES-2/HA-7, MH/HA-7, and KF/HA-7 cells. On ovarian carcinoma cells, high cell surface HA levels seem to inversely correlate with their capacity to adhere and disseminate to the peritoneum. Considering that peritoneum implantation is the primary ovarian cancer complication, HA cell surface expression may be considered a property associated with a less aggressive phenotype, which is contrary to the general perception that HA expression is associated with malignant progression.


Assuntos
Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Epitélio/metabolismo , Feminino , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Regulação Neoplásica da Expressão Gênica , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Humanos , Receptores de Hialuronatos/genética , Hialuronan Sintases , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Cavidade Peritoneal/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Indian J Dent Res ; 22(3): 493-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22048598

RESUMO

AIM: The aim of this study was to semiquantitatively analyze the immunohistochemical expression pattern of CD44 standard (CD44s) and variant (CD44v) isoforms in leukoplakias using a panel of monoclonal antibodies recognizing epitopes of CD44s and of the variant exons v5 and v6. OBJECTIVE: To evaluate the efficacy of CD44s and CD44 v5, v6 immunoexpression as possible molecular markers in detecting high-risk leukoplakias when screening for this oral precancer. MATERIALS AND METHODS: Samples of oral leukoplakia (40 cases) and of normal mucosa (10 cases) were evaluated. Oral leukoplakia was graded into: hyperkeratosis without dysplastic change (8 cases), mild dysplasia (13 cases), moderate dysplasia (10 cases), and severe dysplasias (9 cases). Expression of CD44s,v5, v6 was analyzed by immunohistochemistry in a semiquantitative manner. Three areas of epithelium were scored B, S, and C, i.e., stratum basale, stratum corneum, and stratum spinosum, respectively in leukoplakias. Scoring of all specimens followed a two-parameter system, which implemented percentage of positive cells and staining intensities. Statistical analyses for each parameter of all groups and normals, mean, and standard deviation were calculated by using computer software package EPISTAT. RESULTS: In normal epithelium CD44s, CD44v5, and CD44v6 were expressed as membranous proteins localized on the surface of epithelial cells. Both basal and spinous layer of epithelia expressed strong positive staining of CD44s, v5, v6 which then gradually faded into the negative staining of the superficial keratin layer. Profile of CD44s and v5 revealed that the mean levels of stratum B, S, and C in normal cases were comparable to the study cases and by Student 't' test P>0.05 not significant. There was, however, a statistically significant decrease in the expression of v6 with increasing grades of dysplasias when compared with normal mucosa. CONCLUSION: Among CD44s and its variant isoforms,v5, v6, in this study, variant isoform v6 may serve as a marker in detecting high-risk leukoplakias.


Assuntos
Células Epiteliais/metabolismo , Receptores de Hialuronatos/metabolismo , Leucoplasia Oral/metabolismo , Mucosa Bucal/metabolismo , Lesões Pré-Cancerosas/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Células Epiteliais/patologia , Feminino , Humanos , Imuno-Histoquímica , Leucoplasia Oral/patologia , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Estudos Prospectivos , Isoformas de Proteínas , Valores de Referência
12.
BMC Cancer ; 7: 7, 2007 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-17222331

RESUMO

BACKGROUND: The lymphatic vessels play a crucial role in a variety of human cancers since tumour cell lymphatic invasion significantly influences prognosis. It is not known if pre-existing lymphatics are enough for tumour dissemination or de novo development is necessary. VEGFR-3 is an angiogenetic mediator for both lymphatic and blood vessels during embryonic development, and only for lymphatics after birth. VEGF is a mediator of both vasculogenesis and angiogenesis, regulates the growth of lymphatics in various experimental models, and is produced in many solid tumours. CD44 mediates hyaluronic acid (HA)-dependent cell adhesion: besides promoting invasion, this interaction also supports neoangiogenesis that indirectly stimulates tumour cell proliferation. The expression of VEGF-C (Vascular Endothelial Growth Factor-C), its receptor VEGFR-3 and CD44, were studied on feline mammary samples to assess the importance of lymphangiogenesis and lymphangiotrophism in neoplasia. METHODS: Samples were taken from six normal mammary glands (NMG), ten benign (BT) and 32 malignant (MT) tumours. Immunohistochemical laminin/VEGFR-3 double stain, VEGF-C and CD44 stains were applied to 4 mum-thick sections, and their expression evaluated in intratumoral/extratumoral and intramammary/extramammary fields. RESULTS: All groups revealed a higher number of lymphatics in the extratumoral/extramammary areas. VEGF-C expression in the epithelium paralleled the number of positive vessels in the NMG, BT and MT, whereas VEGF-C higher expression was noted in the intratumoral fields only in infiltrating MT. CD44 score was lower in extratumoral than intratumoral fields in tumours and showed a significant increase in extramammary/extratumoral fields from NMG to MT. Pearson test showed a significant and inversely proportional correlation between CD44 expression and the number of lymphatic vessels with VEGFR-3 in malignant infiltrating tumours. CONCLUSION: The number of both VEGFR-3 positive and negative lymphatics in the extratumoral and extramammary stroma was significantly higher than intratumoral and intramammary fields respectively in the NMG, BT and MT. This suggests a scant biological importance of intratumoral lymphatics while their higher number is due to the concentration of existing vessels following compression of the extratumoral stroma in spite of a non demonstrable increase from NMG to MT. The tumour model employed provided no evidence of lymphangiogenesis, and metastasis in the regional lymph node develops following the spread through the pre-existing lymphatic network.


Assuntos
Linfangiogênese , Metástase Linfática/fisiopatologia , Vasos Linfáticos/metabolismo , Neoplasias Mamárias Animais/metabolismo , Animais , Biomarcadores/metabolismo , Gatos , Receptores de Hialuronatos/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
13.
J Neurooncol ; 73(2): 109-15, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15981099

RESUMO

Gliomatosis cerebri (GC) is a rare brain tumor characterized by widespread infiltration of large parts of the brain and sometimes even the spinal cord. To determine the cause of this extraordinary degree of brain invasion, we studied immunoexpression of factors associated with brain infiltration in low-grade and high-grade tumor samples from nine GC cases. We further determined the allelic status of the fibroblastic growth factor receptor 4 (FGFR4) gene at position 388 (arginine [Arg(388)] or glycine [Gly(388)]) in eighteen GC patients, because the presence of at least one Arg(388) allele has been suggested to favor tumor cell motility compared to tumor cells homozygeous for the Gly(388) allele. Immunohistochemical analyses showed that tumor samples from three GC cases expressed Tenascin-C, whereas six cases had CD44 - immunopositive tumor samples. Expression of MMP-9 was not observed in any of the nine GC patients. FGFR4 genotyping revealed the presence of the Arg(388) in 72% of the eighteen GC cases, a frequency similar to the one found in 21 common astrocytomas (71%). In tumor-free control DNA, the Arg(388) phenotype was present in 60%. These data indicate that CD44 expression might be related to the tumor infiltration in GC, and that patients suffering from GC or other common astrocytomas do not have a significantly increased frequency of the tumor cell motility-favoring Arg(388) FGFR4 allele.


Assuntos
Neoplasias Encefálicas/patologia , Receptores de Hialuronatos/metabolismo , Neoplasias Neuroepiteliomatosas/patologia , Receptores de Fatores de Crescimento de Fibroblastos/genética , Adolescente , Adulto , Idoso , Alelos , Arginina/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Neuroepiteliomatosas/genética , Neoplasias Neuroepiteliomatosas/metabolismo , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Índice de Gravidade de Doença , Tenascina/metabolismo
14.
FEBS Lett ; 563(1-3): 23-7, 2004 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-15063717

RESUMO

The non-covalent bond between aggrecan and hyaluronan is critical for maintaining the normal structure and function of the extracellular matrix in articular cartilage. The failure of this bond can cause the loss of aggrecan and destruction of the extracellular matrix of articular cartilage. In this study, the rupture force of the single bond between hyaluronan and hyaluronan binding protein - the complex of the hyaluronan binding region of aggrecan and link protein - was directly measured with a nanomechanical testing system as 40+/-11 pN. The results were compared to a theoretical prediction based on a smart version of the Monte Carlo simulation.


Assuntos
Cartilagem Articular/metabolismo , Proteínas da Matriz Extracelular , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Agrecanas , Simulação por Computador , Matriz Extracelular/metabolismo , Lectinas Tipo C , Modelos Teóricos , Peso Molecular , Método de Monte Carlo , Proteínas/metabolismo , Proteoglicanas/metabolismo
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