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1.
HNO ; 2024 Feb 26.
Artículo en Alemán | MEDLINE | ID: mdl-38409556

RESUMEN

The prevalence of analgesic intolerance syndrome (AIS), internationally known as NSAID-exacerbated respiratory disease (NERD), is reported to be 0.5-5.7% in the general population. The disease often begins with nasal symptoms, which are later joined by chronic rhinosinusitis with nasal polyposis (CRSwNP), asthma, and respiratory hypersensitivity reactions following use of nonsteroidal anti-inflammatory drugs (NSAIDs). In the setting of chronic respiratory disease, the type 2 inflammatory endotype is predominant in approximately 80% of patients with CRSwNP, rendering biologics directed against interleukin (IL)-4, IL­5, IL-13, and IgE of high clinical interest, particularly in patients with severe CRSwNP and NERD. NERD is often associated with CRSwNP and asthma. Patients with CRSwNP and NERD have been treated, among other therapies, with aspirin therapy after desensitization (ATAD). With the approval of monoclonal antibodies for CRSwNP and asthma, the question arises as to what extent ATAD, which is associated with undesirable side effects, is still useful in the treatment of CRSwNP. In this manuscript, the use of ATAD in CRSwNP patients is discussed from different medical and socioeconomic points of view, both alternatively to or in combination with monoclonal antibodies. Accordingly, both ATAD and biologics continue to play a supporting role in modern treatment of CRSwNP in NERD patients, and should be used judiciously to complement each other.

2.
Expert Rev Clin Immunol ; 19(11): 1399-1406, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37551742

RESUMEN

INTRODUCTION: Approximately 5%-12% of the population worldwide suffer from chronic rhinosinusitis (CRS). CRS is defined as a chronic respiratory disease and is considered to be a risk factor for COVID-19 patients. AREAS COVERED: A non-systematic literature research was conducted on COVID-19 and treatment options for CRSwNP. The latest international publications in medical databases, international guidelines, and the internet were reviewed. Since there were no publications on all aspects of this topic during the pandemic, we included our own experience in this report. Based on the conducted literature research in addition to our previously reported experience, we discuss the treatment of CRSwNP during the COVID-19 pandemic and what can be taken for future pandemics. EXPERT OPINION: Intranasal corticosteroids remain the standard treatment for CRS in patients with SARS-CoV-2 infection. Indications for surgical treatment of CRS should be critically evaluated and reserved for patients with complications and those with no other treatment options. For this purpose, COVID-19 status should be known if possible and, in case of unclear status (emergency), using appropriate personal protective equipment. Systemic corticosteroids should be avoided were possible. Biological treatment should be continued under careful monitoring in uninfected patients and should be temporarily interrupted during COVID-19 infection.

3.
HNO ; 71(6): 413-421, 2023 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-37171595

RESUMEN

Allergic rhinitis is an IgE-mediated, type­2 inflammatory disease. neuropeptides are released by neurons and interact with immune cells. Via colocalization, neuroimmune cell units such as nerve-mast cell units, nerve-type 2 innate lymphoid cell (ILC2) units, nerve-eosinophil units, and nerve-basophil units are formed. Markedly elevated tryptase levels were found in nasal lavage fluid and were strongly associated with neuropeptide levels. A close anatomical connection allows bidirectional communication between immune and neuronal cells. Transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential ankyrin repeat 1 (TRPA1) are critically involved in immunological reactions in the setting of allergic rhinitis. Neuroimmunological communication plays an important role in the inflammatory process, so that allergic rhinitis can no longer be considered a purely immunological disease, but rather a combined neuroimmunological disease.


Asunto(s)
Inmunidad Innata , Rinitis Alérgica , Humanos , Linfocitos , Triptasas , Neuronas , Mucosa Nasal
4.
HNO ; 71(5): 337-346, 2023 May.
Artículo en Alemán | MEDLINE | ID: mdl-37041304

RESUMEN

Allergic rhinitis (AR) is a very common disease with a high prevalence worldwide. It is an IgE-mediated type 2 inflammatory disease following exposure to inhalant allergens. A multitude of different neuropeptides including substance P, vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP), nerve growth factor (NGF), and neuromedin U (NMU) can be released via peripheral axon or central reflexes, interact with immune cells, and thus contribute to neurogenic inflammation which causes the nasal hyperreactivity (NHR) characteristic of AR. Independent production of neuroendocrine hormones and neuropeptides by immune cells has also been demonstrated. Neuro-immune cell units arise when immune and neuronal cells colocalize, for which typical anatomic regions are, e.g., the mast cell-nerve functional unit. The focus of this review is the elucidation of neuroimmune communication mechanisms in AR.


Asunto(s)
Neuropéptidos , Rinitis Alérgica , Humanos , Neuroinmunomodulación , Neuropéptidos/análisis , Neuropéptidos/fisiología , Péptido Intestinal Vasoactivo/análisis , Péptido Intestinal Vasoactivo/fisiología , Péptido Relacionado con Gen de Calcitonina/análisis , Péptido Relacionado con Gen de Calcitonina/fisiología , Mucosa Nasal
7.
Laryngorhinootologie ; 102(2): 89-99, 2023 02.
Artículo en Alemán | MEDLINE | ID: mdl-36750110

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the mucous membranes of the nose and sinuses. Eosinophilic inflammation is described as a common endotype. The anti-IL5 antibody mepolizumab was approved in November 2021 as an add-on therapy to intranasal glucocorticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps when systemic glucocorticosteroids or surgery do not provide adequate disease control. While national and international recommendations exist for the use of mepolizumab in CRSwNP, it has not yet been adequately specified how this therapy is to be monitored, what follow-up documentation is necessary, and when it should be terminated if necessary. METHODS: A literature search was performed to analyze previous data on the treatment of CRSwNP with mepolizumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to and including 10/2022 were considered. RESULTS: Based on the international literature and previous experience by an expert panel, recommendations for follow-up, adherence to therapy intervals and possible therapy breaks, as well as termination of therapy when using mepolizumab for the indication CRSwNP in the German health care system are given on the basis of a documentation sheet. CONCLUSIONS: Understanding the immunological basis of CRSwNP opens up new non-surgical therapeutic approaches with biologics for patients with severe, uncontrolled courses. Here, we provide recommendations for follow-up, adherence to therapy intervals, possible therapy pauses, or discontinuation of therapy when mepolizumab is used as add-on therapy with intranasal glucocorticosteroids to treat adult patients with severe CRSwNP that cannot be adequately controlled with systemic glucocorticosteroids and/or surgical intervention.


Asunto(s)
Medicina Ambiental , Pólipos Nasales , Procedimientos Quírurgicos Nasales , Rinitis , Sinusitis , Adulto , Humanos , Rinitis/tratamiento farmacológico , Enfermedad Crónica , Sinusitis/tratamiento farmacológico , Atención a la Salud
8.
Laryngorhinootologie ; 101(11): 855-865, 2022 11.
Artículo en Alemán | MEDLINE | ID: mdl-36150698

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the nasal and paranasal mucosa. A Type-2 inflammation is described as the most common endotype. Since October 2019 the anti-IL-4/-IL-13 antibody dupilumab has been approved in Germany as an add-on therapy to intranasal corticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps, when systemic corticosteroids alone or surgery do not provide adequate disease control. While recommendations for the use of dupilumab in CRSwNP exist at both national and international levels, until now it has not been adequately established, how therapy should be monitored and when it should be discontinued in the German Health Care System. METHODS: A literature search was performed analyzing previous data on the treatment of CRSwNP with dupilumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to 05/2022 were included. RESULTS: Based on international literature and previous experience, recommendations are given by an expert panel for follow-up and possible therapy breaks, therapy intervals or termination of therapy when using dupilumab for the indication CRSwNP in the German health care system based on a documentation form. CONCLUSIONS: Understanding the immunological basis of CRSwNP opens new non-surgical therapy approaches with biologics for patients with severe courses. The authors give recommendations for follow-up, possible therapy breaks, therapy intervals and a termination for dupilumab treatment as add-on therapy with intranasal corticosteroids for the treatment of adult patients with severe CRSwNP that cannot be adequately controlled with systemic corticosteroids and/or surgical intervention.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Adulto , Humanos , Pólipos Nasales/tratamiento farmacológico , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Enfermedad Crónica , Corticoesteroides/uso terapéutico , Atención a la Salud , Documentación
9.
Laryngorhinootologie ; 101(4): 284-294, 2022 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-35168284

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the paranasal sinus mucosa with eosinophilic inflammation as the most common endotype. The anti-IL5 antibody mepolizumab was approved for the treatment of severe CRSwNP in the EU in November 2021. METHODS: A literature search was performed to analyze the immunology of CRSwNP and determine the available evidence by searching Medline, Pubmed, and the German national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to and including 12/2021 that investigated the effect of mepolizumab in CRSwNP were considered. RESULTS: Based on the international literature and previous experience, recommendations for the use of mepolizumab in CRSwNP in the German health care system are given by an expert panel on the basis of a documentation form. CONCLUSIONS: Understanding about the immunological basis of CRSwNP opens new non-surgical therapeutic approaches with biologics for patients with severe courses. Mepolizumab is approved since November 2021 for add-on therapy with intranasal corticosteroids for the treatment of adult patients with severe CRSwNP who cannot be adequately controlled with systemic corticosteroids and/or surgical intervention.


Asunto(s)
Medicina Ambiental , Pólipos Nasales , Procedimientos Quírurgicos Nasales , Otolaringología , Rinitis , Sinusitis , Corticoesteroides/uso terapéutico , Adulto , Alergólogos , Anticuerpos Monoclonales Humanizados , Enfermedad Crónica , Atención a la Salud , Humanos , Pólipos Nasales/terapia , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico
11.
Cancer Res ; 61(2): 608-11, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11212257

RESUMEN

Risk factors other than human papillomavirus (HPV) infection per se for cervical cancer development have been investigated recently. It was suggested that HPV 16 E6 variants and the p53 codon 72 arginine polymorphism could be progression markers. Indeed, it has been demonstrated that specific E6 variants and p53 arginine were both enriched in cancer. However, especially with regard to the latter, divergent results have been reported. Our aim was thus to investigate whether p53 arginine is important for cervical carcinogenesis by scaling up samples of the two European cohorts, the initial results of which were reported previously. In addition, we have assessed the occurrence of p53 codon 72 arginine, in combination with specific HPV 16 E6 genotypes. We found p53 arginine to be increased in cancer of both cohorts, consistent with our previous concept. Although specific E6 genotypes increased gradually with the severity of the lesion, p53 arginine was enriched in cancer only. Moreover, the frequency of the arginine allele was similar in groups with different E6 genotypes. It is concluded that p53 arginine is a risk factor for cervical cancer but probably acts independently of E6 variants.


Asunto(s)
Proteínas Oncogénicas Virales/genética , Proteínas Represoras , Proteína p53 Supresora de Tumor/genética , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Arginina/genética , Codón/genética , Estudios de Cohortes , Estudios Transversales , Análisis Mutacional de ADN , ADN de Neoplasias/química , ADN de Neoplasias/genética , Femenino , Genotipo , Humanos , Italia , Invasividad Neoplásica , Papillomaviridae/genética , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/virología , Polimorfismo Genético , Polimorfismo Conformacional Retorcido-Simple , Factores de Riesgo , Suecia , Infecciones Tumorales por Virus/genética , Infecciones Tumorales por Virus/virología , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/genética , Displasia del Cuello del Útero/virología
12.
Int J Cancer ; 88(6): 932-7, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11093817

RESUMEN

Oxidative damage is implicated in several chronic diseases including cancer. 8-Hydroxyguanine (8-oxoG) is one of the major promutagenic DNA lesions, which is produced by reactive oxygen species, causes G:C to T:A transversions and is excised by OGG1, an 8-oxoG specific DNA glycosylase/AP-Lyase. In a nested case-control study, gDNA from 105 Caucasian primary non-small cell lung cancer cases and 105 matched controls was screened for 6 possible new polymorphic sites in the human OGG1 gene, detected previously mainly in tumour tissue. The previously described Ser(326)Cys polymorphism was found to be common (allele frequency 0.22) in Caucasians. However, no major difference in Ser(326)Cys genotype distribution could be detected between cases and controls. Two 5;-end polymorphisms previously found in Japanese as well as Arg(131)Gln could not be detected in this population. An Ala(85)Ser polymorphism was found in 2 controls, whereas Arg(46)Gln was detected in only 1 case. As the hOGG1 gene is mapped (3p26.2) to a region frequently lost in primary lung tumours, the frequency of loss of heterozygosity (LOH) was investigated. Forty-three percent of the studied lung tumours exhibited loss of one of the hOGG1 alleles. The wt Ser(326) allele was not predominantly lost in our sample set, which suggests a minor role of this polymorphism in tumourgenesis. Our results show that LOH at the hOGG1 gene locus is a very common occurrence in lung tumourgenesis, possibly leading to increased mutational damage due to ROS in smokers. However, the hOGG1 polymorphisms studied are probably not major contributors to individual lung cancer susceptibility in Caucasians.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Predisposición Genética a la Enfermedad/genética , Glutatión Transferasa/genética , Isoenzimas/genética , Pérdida de Heterocigocidad , Neoplasias Pulmonares/genética , N-Glicosil Hidrolasas/genética , Polimorfismo Genético , Población Blanca , Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Estudios de Casos y Controles , ADN-Formamidopirimidina Glicosilasa , Femenino , Gutatión-S-Transferasa pi , Humanos , Masculino , Persona de Mediana Edad , Técnicas de Amplificación de Ácido Nucleico , Proyectos Piloto , Polimorfismo de Longitud del Fragmento de Restricción
13.
Cancer Lett ; 140(1-2): 75-9, 1999 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10403544

RESUMEN

Insulin receptor substrate-1 (IRS-1) is over-expressed in preneoplastic glycogenotic hepatic foci (GSF) and is gradually down-regulated during progression of these lesions, via mixed cell foci (MCF), to the basophilic neoplastic phenotype. The aim of the present study was to investigate the effect of dehydroepiandrosterone (DHEA), a weak hepatocarcinogen and tumour enhancer, on IRS-1 expression. Hepatocellular lesions were induced by N-nitrosomorpholine followed by DHEA. Under these conditions, many glycogen-poor amphophilic (APF) and intermediate cell foci (ICF) appear, in addition to GSF and MCF. IRS-1 was over-expressed in 215 out of 295 GSF, in 50 out of 53 MCF and in a glycogen-rich mixed cell adenoma. IRS-1 expression was not shown in 147 APF, 51 ICF and 5 amphophilic hepatocellular adenomas, and 3 out of 5 hepatocellular carcinomas showed a weak IRS-1 expression. The results suggest a close association of IRS-1 over-expression with the glycogenotic hepatocellular phenotype. The modulation and enhancement of tumour progression by DHEA is associated with a shift from glycogenosis to amphophilia and basophilia, and a down-regulation of IRS-1 expression.


Asunto(s)
Adenoma de Células Hepáticas/metabolismo , Carcinoma Hepatocelular/metabolismo , Glucógeno/metabolismo , Neoplasias Hepáticas Experimentales/metabolismo , Fosfoproteínas/biosíntesis , Lesiones Precancerosas/metabolismo , Adenoma de Células Hepáticas/inducido químicamente , Animales , Carcinoma Hepatocelular/inducido químicamente , Deshidroepiandrosterona , Femenino , Inmunohistoquímica , Proteínas Sustrato del Receptor de Insulina , Neoplasias Hepáticas Experimentales/inducido químicamente , Nitrosaminas , Ratas , Ratas Sprague-Dawley
14.
Microsc Res Tech ; 40(6): 463-72, 1998 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-9551627

RESUMEN

The ATP-analogue adenylyl(beta,gamma-methylene)diphosphonate was chosen as substrate for the cytochemical localization of adenylate cyclase (AC) activity. The tissues investigated covered normal rat liver and liver from carcinogen-treated animals with preneoplastic lesions and hepatocellular neoplasms, as well as cultured liver cells. The AC reaction product methylene diphosphonate was precipitated with Pb2+ immediately at the place of production. This approach permitted a precise localization of AC activity by light and electron microscopy. The specificity of the AC reaction was demonstrated by control reactions, including inhibition of AC with 2'5'-dideoxyadenosine and activation with forskolin, glucagon, and cholera toxin. Endogenous phosphatases were inhibited with tetramisole and NAD. In normal liver, AC activity was mainly localized in the sinusoidal membrane of hepatocytes. A distinct gradient in activity was observed within the liver lobule. Hepatocytes localized around the terminal hepatic venule showed a significant higher AC activity compared to hepatocytes near the portal tract. AC was clearly decreased in focal preneoplastic liver lesions of the glycogenotic-basophilic cell lineage leading to hepatocellular carcinomas. Cytochemically detected intensity of AC activity corresponded to data obtained by microbiochemical assays in laser-dissected tissue samples. A remarkable interdependence of AC activity and degree of differentiation was also seen in epithelial rat liver cell lines: Highly differentiated cells show high enzyme activity and vice versa, as shown by both cytochemical and biochemical examinations. It is concluded that alterations in cellular signal transduction caused by alterations in AC activity play an important role in hepatocarcinogenesis.


Asunto(s)
Adenilil Ciclasas/metabolismo , Neoplasias Hepáticas Experimentales/enzimología , Hígado/enzimología , Lesiones Precancerosas/enzimología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/metabolismo , Inhibidores de Adenilato Ciclasa , Adenilil Ciclasas/análisis , Animales , Carcinógenos , Línea Celular , Transformación Celular Neoplásica/metabolismo , Toxina del Cólera/farmacología , Colforsina/farmacología , Activación Enzimática , Glucagón/farmacología , Hígado/citología , Hígado/efectos de los fármacos , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/metabolismo , Masculino , Microscopía Electrónica , Microscopía de Contraste de Fase , Nitrosaminas , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/metabolismo , Ratas , Ratas Sprague-Dawley , Especificidad por Sustrato , Factores de Tiempo
15.
Am J Pathol ; 152(2): 341-5, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9466558

RESUMEN

Insulin receptor substrate-1 (IRS-1) is a multisite docking protein occupying a central position in signaling cascades stimulated by a number of growth factors including insulin. Using Western blotting and immunohistochemistry, we investigated the expression of IRS-1 in more than 400 preneoplastic foci of altered hepatocytes and in 12 hepatocellular carcinomas induced in rats by oral administration of N-nitrosomorpholine. In both N-nitrosomorpholine-treated and untreated rat livers, IRS-1 was demonstrable by Western blotting, but with the exception of a few single hepatocytes it was not detectable in the normal parenchyma by immunohistochemistry. In contrast, immunohistochemistry revealed that IRS-1 was strongly expressed in the majority of foci of altered hepatocytes particularly in approximately 97% of the clear/acidophilic and mixed cell foci showing excessive storage of glycogen (glycogenosis). In glycogen-poor basophilic foci of altered hepatocytes and hepatocellular carcinomas, IRS-1 was not detected by immunohistochemistry, but a weak expression was observed in small subpopulations of three hepatocellular carcinomas containing remnants of glycogen. These results indicate that the focal overexpression of IRS-1 is an early event in hepatocarcinogenesis, which is closely correlated with preneoplastic hepatic glycogenosis. During progression from glycogenotic foci to hepatocellular carcinomas, IRS-1-overexpression is gradually down-regulated, and this late event is associated with a fundamental metabolic shift leading to the malignant neoplastic phenotype.


Asunto(s)
Carcinoma/metabolismo , Enfermedad del Almacenamiento de Glucógeno/metabolismo , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , Fosfoproteínas/metabolismo , Lesiones Precancerosas/metabolismo , Animales , Inmunohistoquímica , Proteínas Sustrato del Receptor de Insulina , Masculino , Ratas , Ratas Sprague-Dawley
16.
Carcinogenesis ; 19(12): 2069-80, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9886559

RESUMEN

Tigroid cell foci (TCF) are a well-defined entity induced in rat liver by chemical carcinogens, their significance for hepatocarcinogenesis being controversial. Using cytomorphological, cytochemical and morphometric approaches, we studied the evolution and fate of TCF sequentially from 7 to 110 weeks in groups of 50 male Sprague-Dawley rats, which remained untreated or received N-nitrosomorpholine (NNM) orally at concentrations of 3 and 1 mg/kg body wt/day for 7 and up to 75 weeks, respectively. An increased incidence of hepatocellular neoplasms developed in exposed animals compared with controls, which was significant for adenomas at both dose levels, and for carcinomas (HCC) after the longer exposure to the lower dose level (P < 0.0001). TCF appeared frequently in addition to other types of proliferative foci of altered hepatocytes (FAH) including clear/acidophilic and mixed cell foci (MCF) in NNM-treated and rarely in untreated rats. Striking similarities in the cellular phenotypes of TCF and many hepatocellular neoplasms indicated the potential of TCF for progression to both adenomas and carcinomas. TCF emerged from xenomorphic cell foci (XCF), which consisted of hypertrophied hepatocytes typically presenting an enlarged nucleus, abundant glycogen, smooth and rough endoplasmic reticulum, altered activities of several enzymes of carbohydrate metabolism and an increased cell proliferation (P < 0.001) compared with the extrafocal parenchyma. TCF shared many features with XCF, but their basophilia and proliferative activity was higher. The number of FAH appearing at the two dose levels of NNM was similar but the average size of TCF and MCF was frequently higher at late time points in the group developing a significantly higher incidence of HCC, which suggests a pronounced acceleration of neoplastic conversion in established preneoplastic cell populations rather than the induction of additional FAH by sustained effects of low doses of carcinogens.


Asunto(s)
Carcinógenos , Transformación Celular Neoplásica/patología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/patología , Nitrosaminas , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/patología , Animales , Ciclo Celular/fisiología , División Celular/fisiología , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Inmunohistoquímica , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratas , Ratas Sprague-Dawley
17.
J Bioenerg Biomembr ; 29(4): 303-13, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9387091

RESUMEN

Biochemical and molecular biological approaches in situ have provided compelling evidence for early bioenergetic changes in hepatocarcinogenesis. Hepatocellular neoplasms regularly develop from preneoplastic foci of altered hepatocytes, irrespective of whether they are caused by chemicals, radiation, viruses, or transgenic oncogenes. Two striking early metabolic aberrations were discovered: (1) a focal excessive storage of glycogen (glycogenosis) leading via various intermediate stages to neoplasms, the malignant phenotype of which is poor in glycogen but rich in ribosomes (basophilic), and (2) an accumulation of mitochondria in so-called oncocytes and amphophilic cells, giving rise to well-differentiated neoplasms. The metabolic pattern of human and experimentally induced focal hepatic glycogenosis mimics the phenotype of hepatocytes exposed to insulin. The conversion of the highly differentiated glycogenotic hepatocytes to the poorly differentiated cancer cells is usually associated with a reduction in gluconeogenesis, an activation of the pentose phosphate pathway and glycolysis, and an ever increasing cell proliferation. The metabolic pattern of preneoplastic amphophilic cell populations has only been studied to a limited extent. The few available data suggest that thyromimetic effects of peroxisomal proliferators and hepadnaviral infection may be responsible for the emergence of the amphophilic cell lineage of hepatocarcinogenesis. The actions of both insulin and thyroid hormone are mediated by intracellular signal transduction. It is, thus, conceivable that the early changes in energy metabolism during hepatocarcinogenesis are the consequence of alterations in the complex network of signal transduction pathways, which may be caused by genetic as well as epigenetic primary lesions, and elicit adaptive metabolic changes eventually resulting in the malignant neoplastic phenotype.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Transformación Celular Neoplásica , Metabolismo Energético , Neoplasias Hepáticas/metabolismo , Animales , Carcinoma Hepatocelular/patología , Glucógeno/metabolismo , Humanos , Insulina/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Neoplasias Hepáticas/patología , Hormonas Tiroideas/farmacología
19.
Mol Pathol ; 50(5): 272-5, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9497920

RESUMEN

Molecular analysis of clinical samples has been hampered by the lack of fresh or frozen specimens and the presence of contaminating background cells within samples obscuring the molecular analysis of the pathological cells of interest. Routine cytology specimens are a ubiquitous and abundant, yet largely untapped, source of clinical samples for molecular analysis. Morphologically defined single cells from peripheral blood smears can be microdissected from contaminating background cells and their whole genome amplified by primer extension preamplification, followed by polymerase chain reaction analysis of the specific DNA of interest. Thus, molecular information can be traced back to the cell of origin in these clinical specimens. This should allow studies on clonality, loss of heterozygosity, mutation, or amplification of multiple loci from one single cell in haematological smears and possibly other clinical cytology specimens.


Asunto(s)
Genoma Humano , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Recolección de Muestras de Sangre/métodos , Separación Celular , Niño , Humanos , Rayos Láser , Linfocitos , Agujas , Reacción en Cadena de la Polimerasa , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre
20.
Cancer Res ; 55(5): 989-90, 1995 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-7867009

RESUMEN

Hereditary renal cell carcinomas invariably develop by the age of 1 year in Eker rats. At the histological level, renal cell carcinomas develop through multiple stages from early preneoplastic lesions (e.g., phenotypically altered tubules) to adenomas. We previously reported that ionizing radiation induces additional tumors (large adenomas and carcinomas) in a linear dose-response relationship and that loss of heterozygosity (LOH) at chromosome 10, where the predisposing tuberous sclerosis (Tsc2) gene is localized, was found in the renal cell carcinomas which developed from hybrid F1 rats carrying the Eker mutation, indicating that in heterozygotes two events (one inherited, one somatic) are necessary to produce at least large adenomas and carcinomas. This study was designed to examine LOH in the earliest preneoplastic lesions, using a laser microdissection procedure. We could accurately dissect single altered renal tubules out of freeze-dried sections and clearly detected LOH in 4 of 19 altered tubules (21%). This is the first demonstration of LOH in single renal tubules. Our present results support the theory of a second, somatic mutation (second hit) as rate-limiting step of renal carcinogenesis in the Eker rat model of dominantly inherited cancer and the tumor suppressor nature of the Tsc2 gene function.


Asunto(s)
Carcinoma de Células Renales/genética , Carcinoma de Células Renales/cirugía , Neoplasias Renales/genética , Neoplasias Renales/cirugía , Terapia por Láser/métodos , Mutación , Lesiones Precancerosas/genética , Lesiones Precancerosas/cirugía , Animales , Secuencia de Bases , Cromosomas , Disección , Femenino , Eliminación de Gen , Heterocigoto , Túbulos Renales/fisiología , Túbulos Renales/cirugía , Masculino , Microcirugia , Datos de Secuencia Molecular , Fenotipo , Ratas , Ratas Endogámicas BN
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