RESUMO
The aim if this study was to investigate the hypothesis that K-RAS 4A is upregulated in a mineralocorticoid-dependent manner in renal cell carcinoma and that this supports the proliferation and survival of some renal cancers. Expression of the K-RAS in renal tumour tissues and cell lines was examined by real-time PCR and Western blot and mineralocorticoid receptor, and its gatekeeper enzyme 11ß-hydroxysteroid dehydrogenase-2 was examined by immunocytochemistry on a tissue microarray of 27 cases of renal cell carcinoma. Renal cancer cells lines 04A018 (RCC4 plus VHL) and 04A019 (RCC4 plus vector alone) were examined for the expression of K-RAS4A and for the effect on K-RAS expression of spironolactone blockade of the mineralocorticoid receptor. K-RAS4A was suppressed by siRNA, and the effect on cell survival, proliferation and activation of the Akt and Raf signalling pathways was investigated in vitro. K-RAS4A was expressed in RCC tissue and in the renal cancer cell lines but K-RAS was downregulated by spironolactone and upregulated by aldosterone. Spironolactone treatment and K-RAS suppression both led to a reduction in cell number in vitro. Both Akt and Raf pathways showed activation which was dependent on K-RAS expression. K-RAS expression in renal cell carcinoma is at least partially induced by aldosterone. Aldosterone supports the survival and proliferation of RCC cells by upregulation of K-RAS acting through the Akt and Raf pathways.
Assuntos
Aldosterona/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Proliferação de Células , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas ras/metabolismo , 11-beta-Hidroxiesteroide Desidrogenases/metabolismo , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Humanos , Técnicas In Vitro , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Receptores de Mineralocorticoides/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Espironolactona/farmacologia , Análise Serial de Tecidos , Quinases raf/metabolismoRESUMO
AIMS: B cell cutaneous lymphoid hyperplasia (B-CLH) and cutaneous mucosa-associated lymphoid tissue (MALT) lymphoma represent opposite poles of the same disease spectrum. We explored the hypothesis that dendritic cells (DCs) are central in the generation and regulation of such lesions. METHODS AND RESULTS: Immunohistochemistry was used to identify Langerhan cells (LCs), dermal DCs (DDCs) and plasmacytoid DCs (PDCs), as well as mature and alternatively activated DCs, in B-CLH (n = 14) and cutaneous MALT lymphoma (n = 18). PDCs were most numerous in both types of lesion, but there were significantly more PDCs and DDCs and greater numbers of mature DCs in B-CLH. Nevertheless, DCs were still present in cutaneous MALT lymphoma and there were also proportionately more alternatively activated cells. CONCLUSION: Mature DDCs are prime activators of naive T cells and our results suggest that they are likely to be largely responsible for driving the initial proliferation in B-CLH. The results also suggest that PDCs play a central role, and we hypothesize that they dictate the magnitude, duration and direction of the response. In cutaneous MALT lymphoma PDCs are the dominant DC subtype, and may act by damping down the antitumour host immune response, as well as directly stimulating the growth and differentiation of the neoplastic lymphocytes.
Assuntos
Linfócitos B/patologia , Células Dendríticas/imunologia , Transtornos Linfoproliferativos/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos B/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Humanos , Imuno-Histoquímica , Transtornos Linfoproliferativos/metabolismo , Transtornos Linfoproliferativos/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologiaRESUMO
Individual pathologists deal with thousands of diagnostic biopsy and excision specimens annually. At each stage, procedures are in place to limit the possibility of human error, which could result in specimen transposition or contamination. One specimen contaminating another is usually easily identified and rarely causes diagnostic difficulty; however, when it does, the consequences can be very serious. We discuss 5 cases in which concerns over specimen identity and tissue contamination arose and the methodology by which we resolved those concerns. Polymerase chain reaction analysis of each case was carried out using a panel of 12 polymorphic microsatellite markers, specific for chromosomes 13, 18, and 21. These markers are routinely used in the molecular genetics diagnostic laboratory for rapid trisomy screening. In each case, the question of error was satisfactorily resolved. Using this approach, we prevented the real possibility of patients undergoing second invasive procedures. We suggest that this or a similar methodology become a routine part of pathology practice.
Assuntos
Patologia Clínica/normas , Manejo de Espécimes/normas , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 18/genética , Cromossomos Humanos Par 21/genética , Colo/patologia , Neoplasias do Colo/genética , Humanos , Repetições de Microssatélites , Reação em Cadeia da Polimerase/métodos , Fixação de Tecidos/normas , Neoplasias da Bexiga Urinária/patologiaRESUMO
Langerhans cell histiocytosis (LCH) has been described in association with a variety of neoplasms preceding, after, or synchronous with the other tumor. In some cases, a neoplasm may arise as a complication of therapy for LCH, and in others, the association may be coincidental. Synchronous occurrence has been reported most commonly in association with malignant lymphoma in which discrete proliferations of Langerhans cells (LCs) histologically indistinguishable from LCH are seen. In most cases, these LCs are closely related to or intermingling with the primary pathology. The nature of LCs in this context remains elusive with debate as to whether they represent a true clonal neoplasm or an exaggerated reactive phenomenon. The lack of evidence for LCH progression or disease elsewhere strongly supports the latter. We have encountered 5 examples of LCH-like proliferations occurring in the context of other lymphoproliferative disorders. These include 2 cases of mycosis fungoides and 1 of cutaneous B-cell pseudolymphoma, associations that to our knowledge have not been described before. Two patients were female, and the clonality of the LC proliferation was assessed using laser capture microdissection and the human androgen receptor. The results showed that the LCs forming discrete nodules in a case of cutaneous B-cell pseudolymphoma and a case of Hodgkin's lymphoma were polyclonal. This suggests that, at least in a proportion of cases, the aggregates of LCs occasionally identified within other lymphoproliferative lesions represent a reactive proliferation rather than a potentially aggressive second neoplasm.
Assuntos
Histiocitose de Células de Langerhans/patologia , Células de Langerhans/patologia , Transtornos Linfoproliferativos/patologia , Neoplasias Primárias Múltiplas/patologia , Segunda Neoplasia Primária/patologia , Adulto , Linfócitos B/patologia , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Células Clonais , Evolução Fatal , Feminino , Histiocitose de Células de Langerhans/complicações , Histiocitose de Células de Langerhans/metabolismo , Humanos , Células de Langerhans/metabolismo , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/metabolismo , Masculino , Pessoa de Meia-Idade , Micose Fungoide/complicações , Micose Fungoide/patologia , Neoplasias Primárias Múltiplas/complicações , Neoplasias Primárias Múltiplas/metabolismo , Segunda Neoplasia Primária/complicações , Segunda Neoplasia Primária/metabolismo , Pseudolinfoma/complicações , Pseudolinfoma/patologia , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/patologiaAssuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Succinato Desidrogenase/genética , Sequência de Bases , Feminino , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Mitocôndrias/patologia , Linhagem , Reação em Cadeia da PolimeraseRESUMO
Keratin 7 (K7) is a Type II member of the keratin superfamily and despite its widespread expression in different types of simple and transitional epithelia, its functional role in vivo remains elusive, in part due to the lack of any appropriate mouse models or any human diseases that are associated with KRT7 gene mutations. Using conventional gene targeting in mouse embryonic stem cells, we report here the generation and characterisation of the first K7 knockout mouse. Loss of K7 led to increased proliferation of the bladder urothelium although this was not associated with hyperplasia. K18, a presumptive type I assembly partner for K7, showed reduced expression in the bladder whereas K20, a marker of the terminally differentiated superficial urothelial cells was transcriptionally up-regulated. No other epithelia were seen to be adversely affected by the loss of K7 and western blot and immunofluorescence microscopy analysis revealed that the expression of K8, K18, K19 and K20 were not altered in the absence of K7, with the exception of the kidney where there was reduced K18 expression.
Assuntos
Efeito Fundador , Queratina-7/genética , Camundongos Knockout/genética , Bexiga Urinária/metabolismo , Urotélio/metabolismo , Animais , Proliferação de Células , Feminino , Regulação da Expressão Gênica , Queratina-18/genética , Queratina-18/metabolismo , Queratina-19/genética , Queratina-19/metabolismo , Queratina-20/genética , Queratina-20/metabolismo , Queratina-7/deficiência , Queratina-8/genética , Queratina-8/metabolismo , Masculino , Camundongos , Camundongos Knockout/metabolismo , Ligação Proteica , Bexiga Urinária/citologia , Urotélio/citologiaRESUMO
Multiple self-healing squamous epithelioma (MSSE), also known as Ferguson-Smith disease (FSD), is an autosomal-dominant skin cancer condition characterized by multiple squamous-carcinoma-like locally invasive skin tumors that grow rapidly for a few weeks before spontaneously regressing, leaving scars. High-throughput genomic sequencing of a conservative estimate (24.2 Mb) of the disease locus on chromosome 9 using exon array capture identified independent mutations in TGFBR1 in three unrelated families. Subsequent dideoxy sequencing of TGFBR1 identified 11 distinct monoallelic mutations in 18 affected families, firmly establishing TGFBR1 as the causative gene. The nature of the sequence variants, which include mutations in the extracellular ligand-binding domain and a series of truncating mutations in the kinase domain, indicates a clear genotype-phenotype correlation between loss-of-function TGFBR1 mutations and MSSE. This distinguishes MSSE from the Marfan syndrome-related disorders in which missense mutations in TGFBR1 lead to developmental defects with vascular involvement but no reported predisposition to cancer.
Assuntos
Mutação , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Neoplasias Cutâneas/genética , Sequência de Aminoácidos , Sequência de Bases , Carcinoma/genética , Carcinoma/metabolismo , Códon sem Sentido , Sequência Conservada , Primers do DNA/genética , Feminino , Mutação da Fase de Leitura , Estudos de Associação Genética , Haplótipos , Humanos , Ceratoacantoma/genética , Ceratoacantoma/metabolismo , Masculino , Síndrome de Marfan/genética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Estrutura Terciária de Proteína , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/química , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Homologia de Sequência de Aminoácidos , Neoplasias Cutâneas/metabolismoRESUMO
Follicular lymphoma (FL) is a common subtype of low grade B-cell non-Hodgkin lymphoma (NHL). Although this form of lymphoma often pursues an indolent course, in some cases it may behave in a more aggressive manner. Clinical and histological parameters have been shown to correlate with an adverse prognosis but a number of cytogenetic abnormalities may also be associated with aggressive disease. Although, the t(14;18) in itself does not affect outcome in cases of FL, secondary abnormalities that occur in a complex polyploid karyotype may identify cases with a poor prognosis. It is unusual to find both t(14;18) and C-MYC translocation in the same tumour; those cases in which it has been described include examples of high-grade B-cell NHL (either de novo or transformed FL) or B-cell acute lymphoblastic lymphoma. In this report, three cases of FL are described in which both t(14;18) and a C-MYC translocation were identified at presentation. We also summarize four further cases from the literature. This is a small series but one which raises the possibility that the presence of a C-MYC translocations at presentation may identify a particularly aggressive subtype of FL. Further studies are required to investigate the true incidence of this aberration, the impact on C-MYC regulation, clinical course and response to treatment.