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1.
Klin Padiatr ; 222(2): 73-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19790029

RESUMO

BACKGROUND: Cat-scratch disease (CSD) is common in children, however the wide spectrum of the clinical presentation of CSD may lead to delayed diagnosis. An atypical presentation of CSD includes in its differential diagnosis diseases such as tuberculosis, other mycobacterioses, Epstein-Barr-Virus infection (EBV) or malignant disease. Since, in a small number of cases, these diseases may be present concurrently with an active CSD, it is important to consider CSD early in the differential diagnosis and order the appropriate tests. These tests include serology and, where possible, histology including molecular diagnostic methods on tissue specimens. PATIENTS AND METHOD: We performed a case series of five patients treated in our hospital with a clinical diagnosis of cat-scratch disease, confirmed by serology. An analysis of the history and clinical symptoms associated specifically with an atypical presentation of CSD was performed. RESULTS: The clinical presentation of CSD no longer encompasses the original typical description from 1950, but rather presents with a wide spectrum of signs and symptoms, including the absence of a documented cat scratch, fever, primary lesions or peripheral lymphadenopathy. Low density lesions in spleen, liver and lymph nodes are typical findings in ultrasound, MRI, or CT. Ignoring CSD as a possibility in investigating possible malignancy or tuberculosis could lead to unnecessary hospitalisation and delay in the proper treatment. CONCLUSION: CSD should also be considered in differential diagnosis of any patient with intraabdominal lymphadenopathy, abdominal pain and fever of unknown origin. A careful history is important, however, often patients with CSD have no history of contact with cats. Therefore in atypical cases of CSD the finding of other clinical symptoms and performance of specific diagnostic tests is important. Our experience suggests that early serological testing for Bartonella henselae should be performed and may avoid invasive diagnostic procedures.


Assuntos
Bartonella henselae , Doença da Arranhadura de Gato/diagnóstico , Adolescente , Animais , Antibacterianos/uso terapêutico , Biópsia , Mordeduras e Picadas/complicações , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Doença da Arranhadura de Gato/tratamento farmacológico , Gatos , Criança , Pré-Escolar , Diagnóstico Diferencial , Quimioterapia Combinada , Feminino , Humanos , Laparoscopia , Fígado/patologia , Linfonodos/patologia , Imageamento por Ressonância Magnética , Masculino , Baço/patologia , Tomografia Computadorizada por Raios X , Ultrassonografia
2.
Br J Cancer ; 101(8): 1410-6, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19755982

RESUMO

BACKGROUND: Dyskerin encoded by the DKC1 gene is a predominantly nucleolar protein essential for the formation of pseudouridine in RNA and the telomerase RNA subunit hTR. Inherited mutations inactivating dyskerin cause dyskeratosis congenita, a syndrome with progeroid features characterised by skin defects and haematopoiesis failure, as well as cancer susceptibility. In this study, we report DKC1 overexpression in prostate cancers. METHODS: Expression of DKC1 was measured by quantitative RT-PCR in prostate cancer tissues in relation to hTR and the proliferation marker MKI67. Effects of dyskerin downregulation on proliferation, apoptosis and senescence of prostate cancer cell lines were determined. RESULTS: DKC1 was significantly overexpressed in prostate cancers, particularly in high-stage and recurring cases, correlating moderately with hTR and MKI67. Dyskerin downregulation in prostate carcinoma cell lines by siRNA diminished cell proliferation, but elicited neither apoptosis nor senescence. Apoptosis induction by TNF-alpha or tunicamycin was not enhanced. Long-term downregulation led predominantly to cell shrinking and loss of adhesion. INTERPRETATION: DKC1 upregulation in prostate cancers is common and likely to be necessary for extensive tumour growth. The phenotype of prostate carcinoma cell lines after dyskerin downregulation suggests that its most critical function is sustaining protein biosynthesis. Intriguingly, compromised function and overexpression of dyskerin can both contribute to cancer development.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Proteínas Nucleares/fisiologia , Neoplasias da Próstata/patologia , Apoptose , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Masculino , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , RNA Mensageiro/análise , RNA Interferente Pequeno/genética , Telomerase/genética
3.
Eur J Med Res ; 14(6): 240-3, 2009 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-19541583

RESUMO

Desmoid tumors are fibroblastic/myofibroblastic neoplasms, which originate from musculo-aponeurotic structures and are classified as deep fibromatoses. Despite their benign histologic appearance and lack of metastatic potential, desmoid tumors may cause aggres?sive local infiltrations and compression of surrounding structures. They are often associated with female gender, familial adenomatous polyposis (FAP) and sporadically may occur at sites of previous trauma, scars or irradiation. Molecular studies have demonstrated that these patients are associated with a bi-allelic APC mutation in the affected tissue. Radical tumor resection with free margins remains the first therapy of choice. In cases with anatomical or technical limitations for a wide excision, radiation therapy represents a proven and effective alternative or supplementary treatment.


Assuntos
Fibromatose Abdominal/patologia , Fibromatose Agressiva/patologia , Neoplasias Torácicas/patologia , Parede Torácica/patologia , Adolescente , Feminino , Fibromatose Abdominal/diagnóstico por imagem , Fibromatose Abdominal/terapia , Fibromatose Agressiva/diagnóstico por imagem , Fibromatose Agressiva/terapia , Humanos , Masculino , Radiografia Torácica/métodos , Neoplasias Torácicas/diagnóstico por imagem , Neoplasias Torácicas/terapia , Parede Torácica/diagnóstico por imagem , Parede Torácica/cirurgia , Tomografia Computadorizada por Raios X
4.
Exp Clin Endocrinol Diabetes ; 117(2): 95-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18563680

RESUMO

The transition of toxic or nodular goiter to Graves' disease is known as a rare side effect of (131)I therapy. Here, we report the case of a 46-year-old German female with posttherapeutical Graves' disease after surgery of a multinodular goiter. Although the major part of the thyroid was excised the patient suffered from manifest Graves' disease including typical clinical and laboratory findings. Prior to surgery, no TSH receptor antibodies were found, although low TPO antibody titres could already be detected. It may thus be assumed that the therapeutic manipulation elicited the key change towards a TSH receptor antibody production in a predisposed organ or alternatively deteriorated a mild unapparent pre-existing Graves' disease. It might be concluded that the possibility of posttherapeutical Graves' disease should be considered in the presence of TPO antibodies prior to the surgical intervention.


Assuntos
Bócio Nodular/cirurgia , Doença de Graves/patologia , Feminino , Doença de Graves/imunologia , Humanos , Pessoa de Meia-Idade
5.
Eur J Med Res ; 13(6): 299-303, 2008 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-18558557

RESUMO

BACKGROUND: S-100B is a calcium binding acute phase protein and a potential biomarker for brain injury. In prior studies elevated plasma S-100B levels were detected in stroke and severe head trauma. The aim of this study was to evaluate whether S-100 B is elevated during cerebral radiotherapy and whether that is associated with adverse outcomes. MATERIAL AND METHODS: In this prospective pilot study, 45 patients (25 males, 20 females, median age 58 (17-81)) underwent cerebral radiation therapy because of a primary or metastaic cerebral malignancy. 39 patients were included in the evaluation. 6 patients died during the study period. S-100 plasma concentrations were measured with an electrochemiluminescence immunoassay on admission and weekly during radiation therapy for the duration of 6 weeks. In 10 healthy young volunteers (5 males, 5 females, median age 32 (28-36)) S-100 B plasma levels were measured weekly for 6 weeks as a negative control. Furthermore, in an active control 10 patients (4 males, 6 females, median age 68 (64-76)) with stroke (7 = major stroke, 3 = lacunar infarct) S- 100 B plasma levels were measured for 7 consecutive days after the event. RESULTS: During radiotherapy S-100 B plasma concentrations increased from median baseline values of 0.030 microg/l to 0.044 microg/l. For the time of radiation therapy most patients showed a mild increase, but absolute plasma values were still within the normal range. In the control group of healthy volunteers S-100 B remained unchanged. In stroke patients S-100 B increased to maximum values of 1.7 microg/l three days after the event. In the 3 patients with lacunar infarcts no increase of S-100 B levels could be detected. CONCLUSION: Brain irradiation leads to a mild increase of S-100 B plasma levels. However, the absolute rise was far weaker compared to that seen in major brain injuries.


Assuntos
Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Regulação da Expressão Gênica , Fatores de Crescimento Neural/biossíntese , Proteínas S100/biossíntese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Radiografia , Radioterapia/métodos , Subunidade beta da Proteína Ligante de Cálcio S100
6.
Eur J Med Res ; 13(4): 139-46, 2008 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18504168

RESUMO

Throughout the past decade the treatment of rectal carcinoma has improved remarkably. Today, individualized multimodality treatment allows local and distant tumor freedom with preservation of anorectal and genitourinary function in a majority of patients. Radiotherapy is elementary in reducing the risk of local recurrence whereas chemotherapy including promising novel agents prevents or eliminates distant metastases. However, surgery revolutionized by TME (total mesorectal excision) remains the only curative treatment for rectal carcinoma. In this study the authors review the developments as well as the current status of modern treatment for rectal carcinoma.


Assuntos
Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Retais/cirurgia , Neoplasias Retais/terapia , Terapia Combinada , Humanos , Neoplasias Retais/diagnóstico por imagem , Tomografia Computadorizada por Raios X
7.
J Cancer Res Clin Oncol ; 134(10): 1071-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18392850

RESUMO

OBJECTIVES: Due to PSA screening and increased awareness, prostate cancer (PCa) is identified earlier resulting in smaller diagnostic samples on prostate needle biopsy. Because Gleason grading plays a critical role in treatment planning, we undertook a controlled study to evaluate interobserver variability among German pathologists to grade small PCas using a series of tissue microarray (TMA) images. METHODS: We have previously demonstrated excellent agreement in Gleason grading using TMAs among expert genitourinary pathologists. In the current study, we identified 331 TMA images (95% PCa and 5% benign) to be evaluated by an expert PCa pathologist and subsequently by practicing pathologists throughout Germany. The images were presented using the Bacus Webslide Browser on a CD-ROM. Evaluations were kept anonymous and participant's scoring was compared to the expert's results. RESULTS: A total of 29 German pathologists analysed an average of 278 images. Mean percentage of TMA images which had been assigned the same Gleason score (GS) as done by the expert was 45.7%. GSs differed by no more than one point (+/-1) in 83.5% of the TMA samples evaluated. The respondents were able to correctly assign a GS into clinically relevant categories (i.e. <7, 7, >7) in 68.3% of cases. A total of 75.9% respondents under-graded the TMA images. Gleason grading agreement with the expert reviewer correlated with the number of biopsies evaluated by the pathologist per week. Years of diagnostic experience, self-description as a urologic pathologist or affiliation with a university hospital did not correlate with the pathologist's performance. CONCLUSION: The vast majority of participants under-graded the small tumors. Clinically relevant GS categories were correctly assigned in 68% of cases. This raises a potentially significant problem for pathologists, who have not had as much experience evaluating small PCas.


Assuntos
Patologia Cirúrgica/normas , Neoplasias da Próstata/patologia , Análise Serial de Tecidos , Biópsia por Agulha , Alemanha , Humanos , Masculino , Variações Dependentes do Observador , Neoplasias da Próstata/epidemiologia , Reprodutibilidade dos Testes
9.
Endocr Relat Cancer ; 14(2): 245-56, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17639041

RESUMO

Rac proteins of the Rho-like GTPase family, including the ubiquitous Rac1, the hematopoiesis-specific Rac2, and the least-characterized Rac3 play a major role in oncogenic transformation, tumor invasion and metastasis. However, the prognostic relevance of Rac expression in human tumors has not been investigated yet. In the present study, Rac protein expression was analyzed in benign secretory epithelium, high-grade prostatic intraepithelium neoplasia (HG-PIN), and prostate carcinomas of 60 R0-resected radical prostatectomy specimens by semiquantitative immunohistochemistry. Thus, Rac proteins were significantly strongly expressed in HG-PIN (P < 0.001) and prostate carcinomas (P < 0.001) when compared with benign secretory epithelium. Accordingly, all tumor tissues analyzed by isoform-specific real-time PCR (n = 7) exhibited significantly higher RNA expression levels of Rac (i.e. sum of Rac1 and Rac3 expression levels) than the respective benign counterparts (P = 0.018) and this appeared to result mainly from increased expression of the Rac3 isoform as verified by immunoblotting. Univariate analyses showed statistically significant associations of increased Rac protein expression in prostate cancer (P = 0.045), preoperative prostate-specific antigen levels (P = 0.044), pT stage (P = 0.002), and Gleason score (P = 0.001) with decreased disease-free survival (DFS). This prognostic effect of increased protein expression of Rac remained significant even in a multivariate analysis including all these four factors (relative risk = 3.22, 95% confidence interval = 1.04-10.00; P = 0.043). In conclusion, our data suggest that increased Rac protein expression in prostate cancer relative to the corresponding benign secretory epithelium is an independent predictor of decreased DFS and appears to result mainly from increased expression of the Rac3 isoform.


Assuntos
Carcinoma/diagnóstico , Neoplasias da Próstata/diagnóstico , Proteínas rac de Ligação ao GTP/análise , Proteínas rac1 de Ligação ao GTP/análise , Idoso , Carcinoma/patologia , Carcinoma/cirurgia , Intervalo Livre de Doença , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Isoformas de Proteínas/análise , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Proteínas rac de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/genética
10.
Oncogene ; 26(13): 1875-84, 2007 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-16983333

RESUMO

Chronic inflammation increases the risk of cancer and many cancers, including prostate cancer, arise at sites of chronic inflammation. Inducible nitric oxide synthase (iNOS) is an enzyme dominantly expressed during inflammatory reactions. Although synthesis of high amounts of nitric oxide (NO) by iNOS has been demonstrated in pathophysiological processes, such as acute or chronic inflammation, autoimmune diseases or tumorigenesis, the role of iNOS activity in most of these diseases is poorly understood. Analysing prostate cancer biopsies by immunohistochemistry we found iNOS protein expression in tumor cells strongly paralleled by nitrotyrosine suggesting that iNOS is fully active. In vitro, NO inhibits androgen receptor-dependent promoter activity and prostate specific antigen production as well as DNA-binding activity of the androgen receptor (AR) in a concentration-dependent manner. Inhibition of the activity of androgen receptor-dependent reporter constructs is neither owing to diminished AR protein levels nor owing to an inhibition of its nuclear import. In addition, NO inhibits the proliferation of androgen receptor-positive prostate cancer cells significantly more efficiently than proliferation of androgen receptor-negative prostate cancer cells. In summary, our findings suggest that intratumoral iNOS activity favors development of prostate cancer cells that are able to proliferate androgen receptor-independently, thereby promoting prostate tumor progression.


Assuntos
Antagonistas de Receptores de Andrógenos , Óxido Nítrico/fisiologia , Neoplasias da Próstata/patologia , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Imuno-Histoquímica , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Neoplasias da Próstata/enzimologia , Receptores Androgênicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Endocr Relat Cancer ; 13(3): 839-49, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16954433

RESUMO

Sprouty proteins encoded by the SPRY genes act as modulators and feedback inhibitors of signalling by epidermal growth factor (EGF) and fibroblast growth factor (FGF). Overactivity of EGF and FGF signalling common in prostate cancer might therefore be exacerbated by Sprouty down-regulation. Indeed, down-regulation of SPRY1 and SPRY2 expression has been independently reported. We found both genes modestly down-regulated by microarray expression analysis of microdissected prostate cancers and by quantitative RT-PCR in macrodissected specimens compared with benign tissues. Importantly, the decreases paralleled each other and expression levels of both genes were significantly lower in cancers that recurred within the average follow-up period of 32 months. In contrast to a previous report, no hypermethylation was found to accompany down-regulation of SPRY2 in cancer tissues and cell lines. We additionally investigated the expression of an SPRY1 alternative transcript presumed to be specific for fetal tissues and found its expression moderately well correlated with expression of the standard transcript through diverse tissues and cell lines. The present study confirms and extends previous reports by demonstrating concomitant down-regulation and a significant association with recurrence of SPRY genes.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Membrana/genética , Fosfoproteínas/genética , Neoplasias da Próstata/genética , Proteínas/genética , Linhagem Celular Tumoral , Primers do DNA , Amplificação de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Br J Cancer ; 95(8): 1081-6, 2006 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-17003780

RESUMO

The Rac-specific guanine nucleotide exchange factor, Tiam1, plays a major role in oncogenicity, tumour invasion and metastasis but its usefulness as a prognostic marker in human cancer has not been tested yet. In the present study, Tiam1 expression was analysed in benign secretory epithelium, pre-neoplastic high-grade prostatic intraepithelium neoplasia (HG-PIN) and prostate carcinomas of 60 R0-resected radical prostatectomy specimens by semiquantitative immunohistochemistry. Tiam1 proved significantly overexpressed in both HG-PIN (P<0.001) and prostate carcinomas (P<0.001) when compared to benign secretory epithelium. Strong Tiam1 overexpression (i.e. > or =3.5-fold) in prostate carcinomas relative to the respective benign prostatic epithelium was statistically significantly associated with disease recurrence (P=0.016), the presence of lymph vessel invasion (P=0.031) and high Gleason scores (GS) (i.e. > or =7) (P=0.044). Univariate analysis showed a statistically significant association of strong Tiam1 overexpression with decreased disease-free survival (DFS) (P=0.03). This prognostic effect of strong Tiam1 overexpression remained significant in multivariate analysis including preoperative prostate-specific antigen levels, pT stage, and GS (relative risk= 3.75, 95% confidence interval=1.06-13.16; P=0.04). Together, our data suggest that strong Tiam1 overexpression relative to the corresponding benign epithelial cells is a new and independent predictor of decreased DFS for patients with prostate cancer.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/biossíntese , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Idoso , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia , Prognóstico , Prostatectomia , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasia Prostática Intraepitelial/cirurgia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T
14.
Br J Cancer ; 91(5): 985-94, 2004 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-15292941

RESUMO

In prostate carcinoma (PCa) increased DNA methylation ('hypermethylation') occurs at specific genes such as GSTP1. Nevertheless, overall methylation can be decreased ('hypomethylation') because methylation of repetitive sequences like LINE-1 retrotransposons is diminished. We analysed DNA from 113 PCa and 36 noncancerous prostate tissues for LINE-1 hypomethylation by a sensitive Southern technique and for hypermethylation at eight loci by methylation-specific PCR. Hypermethylation frequencies for GSTP1, RARB2, RASSF1A, and APC in carcinoma tissues were each >70%, strongly correlating with each other (P<10(-6)). Hypermethylation at each locus was significantly different between tumour and normal tissues (10(-11)82% of PCas. PCa may fall into three classes, that is, with few DNA methylation changes, with frequent hypermethylation, or with additional LINE-1 hypomethylation.


Assuntos
Metilação de DNA , DNA de Neoplasias/análise , Elementos Nucleotídeos Longos e Dispersos/genética , Neoplasias da Próstata/genética , Aciltransferases/metabolismo , Southern Blotting , Genes APC/fisiologia , Humanos , Masculino , Reação em Cadeia da Polimerase , Prognóstico , Neoplasias da Próstata/classificação , Neoplasias da Próstata/patologia , Receptores do Ácido Retinoico/metabolismo , Proteínas Supressoras de Tumor/metabolismo
15.
Eur J Endocrinol ; 150(6): 837-40, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15191355

RESUMO

Pancreas divisum is the most common congenital anomaly of the pancreas, characterized by missing fusion of the ventral and dorsal pancreatic duct. It may cause pancreatitis, but is rarely associated with malignancy.We report herein for the first time the rare association, in a symptomless patient, of multiple neuroendocrine tumors of the pancreas with pancreas divisum and a failure of the exocrine system. Diagnosis was made incidentally by routine abdominal ultrasound. Laboratory examinations and a fine-needle aspiration revealed the neuroendocrine nature of the tumor. Spleen-preserving left pancreas resection was performed, with evidence of multiple neuroendocrine tumors of the pancreas with the typical histological characteristics. Eighteen months later the patient is still free of tumor burden.


Assuntos
Carcinoma Neuroendócrino/complicações , Pâncreas/anormalidades , Neoplasias Pancreáticas/complicações , Biópsia por Agulha , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia , Tomografia Computadorizada por Raios X
16.
Mol Pathol ; 54(5): 324-30, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11577175

RESUMO

AIMS: Differential display reverse transcription polymerase chain reaction (RT-PCR) was performed to identify genes associated with the invasive potential of human epithelioid sarcoma. METHODS: Two different clonal subpopulations, GRU-1A and GRU-1B, derived from the same human epithelioid sarcoma cell line GRU-1 and known to differ greatly in their invasive potential were compared by means of mRNA fingerprinting. RESULTS: Using a set of 10 arbitrary upstream primers and nine anchored oligo-dT primers, 22 candidate gene fragments were identified; differential expression was confirmed in four of these fragments by northern blot analysis. At the mRNA level, apoferritin light chain was predominantly expressed by the highly invasive cell line GRU-1A. In contrast, the mitochondrial gene M1, encoding cytochrome c oxidase I, and the TI-227H gene were expressed more strongly by the low invasive cell line GRU-1B. Furthermore, a novel gene fragment was identified and cloned that was preferentially expressed in the low invasive cell line GRU-1B, and therefore might have an inhibitory role in invasion. Consequently, this gene fragment was designated as expressed in low invasive sarcoma cells (ELISC-1). CONCLUSIONS: A novel gene fragment (ELISC-1) and three known genes were identified as potential regulators of tumour invasiveness. Cloning of the entire sequence of ELISC-1 and subsequent investigations are required to establish its biological role.


Assuntos
Invasividade Neoplásica/genética , Sarcoma/genética , Antígenos T-Independentes/metabolismo , Apoferritinas/metabolismo , Northern Blotting , Impressões Digitais de DNA , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Expressão Gênica , Humanos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
17.
J Biol Chem ; 276(45): 41889-97, 2001 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-11551917

RESUMO

Rho-like GTPases, including Cdc42, Rac1, and RhoA, regulate distinct actin cytoskeleton changes required for adhesion, migration, and invasion of cells. Tiam1 specifically activates Rac, and earlier studies have demonstrated that Tiam1-Rac signaling affects migration and invasion in a cell type- and cell substrate-specific manner. In the present study, we examined the role of Tiam1-Rac signaling in migration and invasion of human renal cell carcinomas. Stable overexpression of Tiam1 or constitutively active V12-Rac1 in a human renal cell carcinoma cell line (clearCa-28) strongly inhibited cell migration by promoting E-cadherin-mediated cell-cell adhesion. Blocking E-cadherin-mediated adhesion by E-cadherin-specific HAV peptides allowed cells to migrate, but was not sufficient to antagonize Tiam1- and V12-Rac1-induced inhibition of Matrigel invasion, suggesting that Rac may influence invasion also through other mechanisms. Indeed, Tiam1-mediated Rac activation induced transcriptional up-regulation of tissue inhibitor of metalloproteinases-1 (TIMP-1) and post-transcriptional up-regulation of TIMP-2, whereas secretion and activity levels of their counterparts, matrix metalloproteinase-9 and matrix metalloproteinase-2, respectively, were not affected. Application of recombinant TIMP-1 and TIMP-2 proteins significantly inhibited invasion of mock-transfected clearCa-28 cells, supporting a role of TIMPs in Rac-mediated inhibition of invasion. To our knowledge, this is the first evidence that increased Rac signaling may inhibit invasion of epithelial tumor cells by up-regulation of TIMP-1 and TIMP-2.


Assuntos
Carcinoma de Células Renais/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/patologia , Proteínas/fisiologia , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Proteínas rac de Ligação ao GTP/fisiologia , Adesão Celular , Movimento Celular , Fatores de Troca do Nucleotídeo Guanina , Humanos , Metaloproteinase 2 da Matriz/genética , Invasividade Neoplásica , Regiões Promotoras Genéticas , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T , Células Tumorais Cultivadas , Regulação para Cima
18.
Int J Cancer ; 88(3): 369-76, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11054665

RESUMO

Tiam1 activates the Rho-like GTPase Rac1, and studies indicate that Tiam1-Rac1 signaling affects invasion in different ways depending on the cell type studied. However, no investigations on Tiam1 in human tumors have been reported. Here, we show that for 4 of 5 human renal-cell carcinoma (RCC) cell lines the expression levels of Tiam1 tended to be inversely correlated with in vitro invasiveness, whereas no obvious correlation could be found between the expression levels of Rac1 and invasion. Subsequent mutation analysis of these cell lines revealed no mutations in Rac1 but up to 5 different point mutations in the Tiam1 gene. Of these, 1 mutation (A441G) was located in the NH2-terminal pleckstrin homology domain, which is essential for membrane localization and functional activity of Tiam1. By analysis of an additional 30 primary human RCCs, mutation A441G was found in 4 of 35 tumors and tumor cell lines (11.5%) but not in the respective normal kidney tissues. By enzymatic digestion, mutation A441G proved to be heterozygous, suggesting a dominant active function. This was supported by showing that stable over-expression of mutated A441G-Tiam1 induced transformation of NIH3T3 cells, as determined in a colony formation assay, whereas empty vector and wild-type Tiam1 failed to do so. In conclusion, a distinct Tiam1 mutation (A441G) was identified in several human RCCs. This mutation induced transformation of NIH3T3 cells and, hence, might play a major role in the progression of human RCCs. Further analyses on Tiam1 mutations in human tumors might give new clues to their role in tumor progression.


Assuntos
Carcinoma de Células Renais/genética , Endorribonucleases , Neoplasias Renais/genética , Mutação , Proteínas/genética , Células 3T3 , Animais , Carcinoma de Células Renais/patologia , Transformação Celular Neoplásica , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Fatores de Troca do Nucleotídeo Guanina , Humanos , Neoplasias Renais/patologia , Camundongos , Invasividade Neoplásica , Proteínas/fisiologia , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T , Transfecção , Células Tumorais Cultivadas
19.
Br J Cancer ; 82(5): 1063-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10737390

RESUMO

The role of protein kinase C (PKC) in in vitro invasiveness of four different human renal cell carcinoma (RCC) cell lines of the clear cell type was investigated. Different PKC-inhibitors markedly inhibited invasiveness of the highly invasive cell lines, suggesting an invasion-promoting role of PKC in human RCC. Analysis of PKC-isoenzyme expression by protein fractionation and immunoblotting revealed that all cell lines expressed PKC-alpha, -epsilon, -zeta, -mu and -iota as known from normal kidney tissue. Interestingly, PKC-delta, known to be expressed by normal kidney epithelial cells of the rat, was absent on protein and RNA levels in all RCC cell lines investigated and in normal human kidney epithelial cells. PKC-epsilon expression levels correlated positively with a high proliferation activity, but no obvious correlation between expression levels of distinct PKC-isoenzymes and in vitro invasiveness was observed. However, by immunofluorescence microscopy, membrane localisation of PKC-alpha and PKC-epsilon reflecting activation of the enzymes, was associated with a highly invasive potential. In conclusion, our results suggest a role for PKC in invasion of human RCCs and might argue in favour of a particular role of PKC-alpha and PKC-epsilon. Our results further suggest that organ-specific expression patterns of PKC-isoenzymes are not necessarily conserved during evolution.


Assuntos
Carcinoma de Células Renais/enzimologia , Neoplasias Renais/enzimologia , Proteína Quinase C/fisiologia , Carcinoma de Células Renais/patologia , Inibidores Enzimáticos/farmacologia , Humanos , Immunoblotting , Isoenzimas/análise , Isoenzimas/biossíntese , Isoenzimas/fisiologia , Neoplasias Renais/patologia , Invasividade Neoplásica , Proteína Quinase C/análise , Proteína Quinase C/biossíntese , Proteína Quinase C-delta , Frações Subcelulares , Células Tumorais Cultivadas
20.
J Cancer Res Clin Oncol ; 126(12): 682-92, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11153140

RESUMO

The clinical course--and hence the prognosis--of patients suffering from malignant tumors are essentially determined by the capability of tumor cells to metastasize. During the past decade knowledge about genetic aberrations, as well as molecular and cell biological mechanisms which are involved in the regulation of tumor metastasis, has dramatically increased and consequently led to the development of new theoretical and experimental strategies in cancer treatment. The objective of this review is not only to give an overview about the principal cell biological and molecular mechanisms of tumor metastasis, but also to discuss potential therapeutical options resulting from this knowledge.


Assuntos
Moléculas de Adesão Celular/metabolismo , Endopeptidases/metabolismo , Integrinas/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Animais , Morte Celular , Divisão Celular , Movimento Celular , Humanos , Ligantes , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia
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