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1.
Int J Mol Sci ; 25(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38791417

RESUMEN

To create a radiogenomics map and evaluate the correlation between molecular and imaging phenotypes in localized prostate cancer (PCa), using radical prostatectomy histopathology as a reference standard. Radiomic features were extracted from T2-weighted (T2WI) and Apparent Diffusion Coefficient (ADC) images of clinically localized PCa patients (n = 15) across different Gleason score-based risk categories. DNA extraction was performed on formalin-fixed, paraffin-embedded (FFPE) samples. Gene expression analysis of androgen receptor expression, apoptosis, and hypoxia was conducted using the Chromosome Analysis Suite (ChAS) application and OSCHIP files. The relationship between gene expression alterations and textural features was assessed using Pearson's correlation analysis. Receiver operating characteristic (ROC) analysis was utilized to evaluate the predictive accuracy of the model. A significant correlation was observed between radiomic texture features and copy number variation (CNV) of genes associated with apoptosis, hypoxia, and androgen receptor (p-value ≤ 0.05). The identified radiomic features, including Sum Entropy ADC, Inverse Difference ADC, Sum Variance T2WI, Entropy T2WI, Difference Variance T2WI, and Angular Secondary Moment T2WI, exhibited potential for predicting cancer grade and biological processes such as apoptosis and hypoxia. Incorporating radiomics and genomics into a prediction model significantly improved the prediction of prostate cancer grade (clinically significant prostate cancer), yielding an AUC of 0.95. Radiomic texture features significantly correlate with genotypes for apoptosis, hypoxia, and androgen receptor expression in localised prostate cancer. Integration of these into the prediction model improved prediction accuracy of clinically significant prostate cancer.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Persona de Mediana Edad , Anciano , Receptores Androgénicos/genética , Clasificación del Tumor , Imagen por Resonancia Magnética/métodos , Biopsia , Fenotipo , Curva ROC , Variaciones en el Número de Copia de ADN/genética
2.
Scott Med J ; 69(1): 3-9, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37960856

RESUMEN

BACKGROUND: Cardiovascular disease affects over 7 million people in the UK and statins are often prescribed to mitigate cardiovascular risks. The effect of statins on a number of cancers is debated and their effect on Bacillus Calmette-Guérin (BCG) responsiveness in non-muscle invasive urinary bladder cancer (NMIBC) is not fully understood. AIMS: This study aims to explore the difference in HMG Co-A reductase (HMGCR) expression in NMIBC on immunochemistry in BCG responders and non-responders while on statins. METHOD: Three hundred and thirty-two cases of intravesical BCG treatment for high-risk NMIBC between November 2003 and December 2017 were identified. Patients taking statins for at least 12 months before the diagnosis of NIMBC and with a follow-up of at least 5 years were included. They were divided into BCG responders and non-responders. Tumour tissue from these patients was immunohistochemically stained and quantitative image analysis carried out to assess and compare HMGCR expression in the groups. RESULTS & CONCLUSION: This study showed a differential expression of HMGCR in responders vs. non-responders to BCG for high-risk NMIBC on statins. This data should form the basis of a further research and multi-centre study in a larger cohort, using HMGCR as a biomarker of response in patients on statins.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Neoplasias Vesicales sin Invasión Muscular , Neoplasias de la Vejiga Urinaria , Humanos , Adyuvantes Inmunológicos/uso terapéutico , Vacuna BCG/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Recurrencia Local de Neoplasia/patología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología
3.
Cancers (Basel) ; 15(16)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37627133

RESUMEN

The present study aimed to assess the diagnostic test accuracy of different ultrasound scanning technologies in the detection of prostate cancer. A systematic search was conducted using the Cochrane Guidelines for Screening and Diagnostic Tests. We performed a systematic search in the international databases PubMed, Medline, Ovid, Embase and Cochrane Library. Searches were designed to find all studies that evaluated Micro-US, mpUS, SWE and CEUS as the main detection modalities for prostate cancer. This study was registered with Research Registry of systematic review and meta-analysis. The QUADAS-2 tool was utilized to perform quality assessment and bias analysis. The literature search generated 1376 studies. Of these, 320 studies were screened for eligibility, with 1056 studies being excluded. Overall, 26 studies with a total of 6370 patients met the inclusion criteria. The pooled sensitivity for grayscale, CEUS, SWE, Micro-US and mpUS modalities were 0.66 (95% CI 0.54-0.73) 0.73 (95% CI 0.58-0.88), 0.82 (95% CI 0.75-0.90), 0.85 (95% CI 0.76-0.94) and 0.87 (95% CI 0.71-1.03), respectively. Moreover, the pooled specificity for grayscale, CEUS, SWE, Micro-US and mpUS modalities were 0.56 (95% CI 0.21-0.90), 0.78 (95% CI 0.67-0.88), 0.76 (95% CI 0.65-0.88), 0.43 (95% CI 0.28-0.59) and 0.68 (95% CI 0.54-0.81), respectively. In terms of sensitivity, substantial heterogeneity between studies was detected (I2 = 72%, p = 0.000 < 0.05). In relation to specificity, extreme heterogeneity was detected (I2 = 93%, p = 0.000 < 0.05). Some studies proved that advanced ultrasound modalities such as mpUS, Micro-US, shear-wave elastography, contrast enhanced and micro-ultrasound are promising methods for the detection of prostate cancer.

5.
Front Oncol ; 12: 822476, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35530322

RESUMEN

Introduction: Growing evidence suggests that the tumor microenvironment (TME) represented by cellular and acellular components plays a key role in the multistep process of metastases and response to therapies. However, imaging and molecular characterization of the TME in prostate cancer (PCa) and its role in predicting aggressive tumor behavior and disease progression is largely unexplored. The study explores the PCa TME through the characterization of cancer-associated fibroblasts (CAFs) using both immunohistochemistry (IHC) and genomics approaches. This is then correlated with transrectal ultrasound shear wave elastography (USWE)-measured tissue stiffness. Patients and Methods: Thirty patients with clinically localized PCa undergoing radical prostatectomy for different risk categories of tumor (low, intermediate, and high) defined by Gleason score (GS) were prospectively recruited into this study. Prostatic tissue stiffness was measured using USWE prior to surgery. The CAFs within the TME were identified by IHC using a panel of six antibodies (FAP, SMAα, FSP1, CD36, PDGFRα, and PDGFRß) as well as gene expression profiling using TempO-sequence analysis. Whether the pattern and degree of immunohistochemical positivity (measured by Quick score method) and expression of genes characterizing CAFs were correlated with USWE- and GS-measured tissue stiffnesses were tested using Spearman's rank correlation and Pearson correlation. Results: There was a statistically significant correlation between GS of cancers, the pattern of staining for CAFs by immunohistochemical staining, and tissue stiffness measured in kPa using USWE (p < 0.001). Significant differences were also observed in immunohistochemical staining patterns between normal prostate and prostatic cancerous tissue. PDGFRß and SMAα immunostaining scores increased linearly with increasing the USWE stiffness and the GS of PCa. There was a significant positive correlation between increasing tissue stiffness in tumor stroma and SMAα and PDGFRß gene expression in the fibromuscular stroma (p < 0.001). Conclusion: USWE-measured tissue stiffness correlates with increased SMAα and PDGFRß expressing CAFs and PCa GSs. This mechanistic correlation could be used for predicting the upgrading of GS from biopsies to radical surgery and response to novel treatments.

6.
Histopathology ; 56(2): 240-50, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20102403

RESUMEN

AIMS: The heterogeneity within individual distinct cancer types in terms of behaviour, response to therapy and prognosis is well recognized. A major goal of translational research projects has therefore been to define clinically significant subgroups of individual tumour types by analysis of mRNA as well as protein expression. An essential premise of such investigations is that expression of these key molecules is a true reflection of conditions present within the neoplastic cells in vivo. The aim was to investigate the effect of methods of tissue handling and storage on expression of mRNA. METHODS AND RESULTS: mRNA expression in 60 biopsy samples obtained from 10 patients with colorectal tumours was examined. The mRNA expression profile and the level of expression of specific mRNA species were significantly affected by the procedures used for collection and storage of tissue samples. Significant variation in the level of expression (both increased and decreased) of transcripts was detectable after 15 min, and by 120 min there was a fourfold increase in the number of genes with a more than twofold change in the level of expression. CONCLUSIONS: Reliable interpretation of results of gene expression at the mRNA level requires standardized protocols for tissue procurement.


Asunto(s)
Neoplasias Colorrectales/genética , Perfilación de la Expresión Génica , ARN Neoplásico , Biopsia , Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/patología , Criopreservación/métodos , Femenino , Congelación , Humanos , Isquemia , Masculino , Biosíntesis de Proteínas , ARN Mensajero , Reproducibilidad de los Resultados , Factores de Tiempo , Fijación del Tejido/métodos , Transcripción Genética
7.
Int J Cancer ; 124(2): 465-72, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19003963

RESUMEN

We sought to determine whether seliciclib (CYC202, R-roscovitine) could increase the antitumor effects of doxorubicin, with no increase in toxicity, in an MCF7 breast cancer xenograft model. The efficacy of seliciclib combined with doxorubicin was compared with single agent doxorubicin or seliciclib administered to MCF7 cells and to nude mice bearing established MCF7 xenografts. Post-treatment cells and tumors were examined by cell cycle analysis, immunohistochemistry and real-time PCR. Seliciclib significantly enhanced the antitumor effect of doxorubicin without additional murine toxicity. MIB1 (ki67) immunohistochemistry demonstrated reduced proliferation with treatment. The levels of p21 and p27 increased after treatment with doxorubicin or seliciclib alone or in combination, compared to untreated controls. However, no changes in p53 protein (DO1, CM1), survivin or p53 phosphorylation (SER15) were observed in treated tumors compared with controls. In conclusion, the CDK inhibitor seliciclib (R-roscovitine) enhances the antitumor effect of doxorubicin in MCF7 tumors without increased toxicity with a mechanism that involves cell cycle arrest rather than apoptosis.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Quinasas Ciclina-Dependientes/metabolismo , Doxorrubicina/administración & dosificación , Neoplasias Mamarias Animales/tratamiento farmacológico , Purinas/administración & dosificación , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Línea Celular Tumoral , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Sinergismo Farmacológico , Femenino , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Inhibidores de Proteínas Quinasas/administración & dosificación , Roscovitina
8.
FEBS J ; 273(9): 1930-47, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16640557

RESUMEN

Stress protein responses have evolved in part as a mechanism to protect cells from the toxic effects of environmental damaging agents. Oesophageal squamous epithelial cells have evolved an atypical stress response that results in the synthesis of a 53 kDa protein of undefined function named squamous epithelial-induced stress protein of 53 kDa (SEP53). Given the role of deoxycholic acid (DCA) as a potential damaging agent in squamous epithelium, we developed assays measuring the effects of DCA on SEP53-mediated responses to damage. To achieve this, we cloned the human SEP53 gene, developed a panel of monoclonal antibodies to the protein, and showed that SEP53 expression is predominantly confined to squamous epithelium. Clonogenic assays were used to show that SEP53 can function as a survival factor in mammalian cell lines, can attenuate DCA-induced apoptotic cell death, and can attenuate DCA-mediated increases in intracellular free calcium. Deletion of the highly conserved EF-hand calcium-binding domain in SEP53 neutralizes the colony survival activity of the protein, neutralizes the protective effects of SEP53 after DCA exposure, and permits calcium elevation in response to DCA challenge. These data indicate that the squamous cell-stress protein SEP53 can function as a modifier of the DCA-mediated calcium influx and identify a novel survival pathway whose study may shed light on mechanisms relating to squamous cell injury and associated cancer development.


Asunto(s)
Apoptosis/fisiología , Proteínas de Unión al Calcio/fisiología , Calcio/metabolismo , Ácido Desoxicólico/toxicidad , Células Epiteliales/patología , Proteínas de Choque Térmico/fisiología , Proteínas de la Membrana/fisiología , Proteínas de Neoplasias/fisiología , Secuencia de Aminoácidos , Proteínas de Unión al Calcio/biosíntesis , Proteínas de Unión al Calcio/metabolismo , Muerte Celular/fisiología , Línea Celular Tumoral , Supervivencia Celular/fisiología , Células Clonales , Células Epiteliales/metabolismo , Células HCT116 , Proteínas de Choque Térmico/biosíntesis , Humanos , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Transducción de Señal/fisiología
9.
Hum Pathol ; 37(1): 32-9, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16360413

RESUMEN

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.


Asunto(s)
Histiocitosis de Células de Langerhans/patología , Células de Langerhans/patología , Trastornos Linfoproliferativos/patología , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Secundarias/patología , Adulto , Linfocitos B/patología , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Células Clonales , Resultado Fatal , Femenino , Histiocitosis de Células de Langerhans/complicaciones , Histiocitosis de Células de Langerhans/metabolismo , Humanos , Células de Langerhans/metabolismo , Trastornos Linfoproliferativos/complicaciones , Trastornos Linfoproliferativos/metabolismo , Masculino , Persona de Mediana Edad , Micosis Fungoide/complicaciones , Micosis Fungoide/patología , Neoplasias Primarias Múltiples/complicaciones , Neoplasias Primarias Múltiples/metabolismo , Neoplasias Primarias Secundarias/complicaciones , Neoplasias Primarias Secundarias/metabolismo , Seudolinfoma/complicaciones , Seudolinfoma/patología , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/patología
10.
Cancer Res ; 63(15): 4656-61, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12907646

RESUMEN

It is widely accepted that both large-scale chromosomal abnormalities and mutation of specific genes, such as APC, K-ras, and/or p53, occur in the majority of colorectal adenocarcinomas. Whether or not a relationship exists between these different forms of genetic abnormalities was previously unknown. Using comparative genomic hybridization and mutational analysis of APC, K-ras, and p53 to evaluate 50 colorectal adenocarcinomas, we have shown that mutation of p53 is significantly associated with gain of 20q, 13q, and 8q and loss of 18q (P = 0.000, 0.02, 0.044, and 0.001, respectively). Conversely, APC mutation did not associate with any of the above-mentioned aberrations but did associate significantly with gain of 7p (P = 0.01). Gain of chromosomal arm 12p, although a less common aberration, was significantly associated with K-ras mutation (P = 0.011). The associations we have described should refine the search for candidate genes underlying chromosomal aberrations and assist in the definition of distinct pathways in colorectal tumorigenesis.


Asunto(s)
Adenocarcinoma/genética , Aberraciones Cromosómicas , Neoplasias Colorrectales/genética , Proteínas de Unión al ADN , Genes APC , Genes p53 , Genes ras , Mutación , Proteínas Adaptadoras Transductoras de Señales , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Anciano , Anciano de 80 o más Años , Proteínas Portadoras , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Femenino , Genotipo , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Proteínas Proto-Oncogénicas/metabolismo
11.
Methods Mol Biol ; 234: 171-202, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12824532

RESUMEN

Phospho-specific antibody technology has been recently adopted to study p53 phosphorylation both in vivo and in vitro. We have developed and carefully characterized p53 phosphospecific reagents directed to major amino- and carboxy-terminal regulatory sites. The specificities of both polyclonal and monoclonal reagents targeting the same phospho-epitope are discussed. We have defined the major chemical binding determinants for specific monoclonal reagents by determining the relative contribution of charge and sequence to epitope recognition. Remarkably, we have found that the utility of these reagents in different assay systems is not universal and depends both on epitope conformation and affinity. This is reflected in the striking differences in their ability to detect endogenous p53 and recombinant protein. Therefore, we conclude that this novel class of reagents is not generally applicable, but that the utility of each reagent must be determined empirically.


Asunto(s)
Anticuerpos Fosfo-Específicos/metabolismo , Fosfotransferasas/metabolismo , Transducción de Señal/fisiología , Proteína p53 Supresora de Tumor/metabolismo , Aminoácidos/metabolismo , Animales , Activación Enzimática , Ensayo de Inmunoadsorción Enzimática/métodos , Mapeo Epitopo , Epítopos , Humanos , Ratones , Fosforilación , Unión Proteica , Procesamiento Proteico-Postraduccional , Especificidad por Sustrato
12.
Eur J Gastroenterol Hepatol ; 15(1): 41-7, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12544693

RESUMEN

OBJECTIVE: Oesophageal cancer associated with the premalignant condition Barrett's oesophagus has increased in incidence over the last few years. Phase II detoxifying enzymes, including glutathione S-transferases (GSTs) protect the mucosa from carcinogens, which can cause oxidative damage to cells. Therefore, a reduction in these anti-oxidant enzymes can increase the risk of carcinogenesis. The aim of this study was to compare the extent of GST expression in normal oesophageal tissue, Barrett's oesophagus and oesophageal adenocarcinoma. DESIGN: Antibodies raised against GST alpha, GST mu, GST pi and microsomal GST were used to identify expression of these proteins in tissue sections. METHOD: Paraffin-embedded sections were stained using standard immunohistochemical techniques to demonstrate the pattern of expression of GST proteins in biopsy specimens. Twelve sections of Barrett's metaplasia and an equal number of specimens from normal oesophageal tissue were examined, together with sections from adenocarcinoma and normal gastric mucosa. RESULTS: Expression of the GST enzymes appeared to be reduced in Barrett's tissue compared to normal oesophageal tissue. Nuclear staining featured in some of the normal tissue sections, but not in Barrett's tissue. CONCLUSION: The reduction in GST expression suggested in Barrett's tissue is an interesting finding, as it is possible that reduced expression of these detoxifying enzymes may contribute to the risk of development of adenocarcinoma in Barrett's mucosa.


Asunto(s)
Esófago de Barrett/enzimología , Neoplasias Esofágicas/enzimología , Esófago/enzimología , Glutatión Transferasa/metabolismo , Lesiones Precancerosas/enzimología , Adenocarcinoma/enzimología , Progresión de la Enfermedad , Duodeno/enzimología , Epitelio/enzimología , Mucosa Gástrica/enzimología , Humanos , Técnicas para Inmunoenzimas , Neoplasias Gástricas/enzimología
14.
Retin Cases Brief Rep ; 7(4): 328-30, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25383830

RESUMEN

PURPOSE: To discuss surgical options and visual outcome when faced with a diamond intraoperative foreign body during macular hole surgery. METHODS: Case study of an iatrogenic in-the-macular-hole diamond particle noted during macular hole surgery. No attempt to retrieve the diamond from the macular hole was made during surgery. PATIENT: Forty-seven-year-old female patient with a 483-µm macular hole. RESULTS: The patient's macular hole closed over the diamond particle, making it subfoveal. The visual acuity improved from 20/120 to 20/40 with resolution of metamorphopsia. CONCLUSION: It is likely that the inert nature and small size of diamond particles do not significantly affect visual acuity or hole closure and do not cause retinal toxicity. The authors discourage aggressive attempts to remove such particles during surgery.

15.
J Biol Chem ; 283(26): 18012-23, 2008 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-18467333

RESUMEN

Mutation of the p53 gene is a common event during tumor pathogenesis. Other mechanisms, such as mdm2 amplification, provide alternative routes through which dysfunction of the p53 pathway is promoted. Here, we address the hypothesis that elevated expression of pim oncogenes might suppress p53 by regulating Mdm2. At a physiological level, we show that endogenous Pim-1 and Pim-2 interact with endogenous Mdm2. Additionally, the Pim kinases phosphorylate Mdm2 in vitro and in cultured cells at Ser(166) and Ser(186), two previously identified targets of other signaling pathways, including Akt. Surprisingly, at high levels of Pim expression, as would occur in tumors, active, but not inactive, Pim-1 or Pim-2 blocks the degradation of both p53 and Mdm2 in a manner that is independent of Mdm2 phosphorylation, leading to increased p53 levels and, proportionately, p53-dependent transactivation. Additionally, Pim-1 induces endogenous ARF, p53, Mdm2, and p21 in primary murine embryo fibroblasts and stimulates senescence-associated beta-galactosidase levels, consistent with the induction of senescence. Immunohistochemical analysis of a cohort of 33 human mantle cell lymphomas shows that elevated expression of Pim-1 occurs in 42% of cases, with elevated Pim-2 occurring in 9% of cases, all of which also express Pim-1. Notably, elevated Pim-1 correlates with elevated Mdm2 in MCL with a p value of 0.003. Taken together, our data are consistent with the idea that Pim normally interacts with the p53 pathway but, when expressed at pathological levels, behaves as a classic dominant oncogene that stimulates a protective response through induction of the p53 pathway.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Linfoma de Células del Manto/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antígenos CD20/biosíntesis , Línea Celular Tumoral , Células Cultivadas , Genes p53 , Humanos , Ratones , Fosforilación , Activación Transcripcional , Transfección
16.
Leuk Lymphoma ; 49(3): 470-6, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18297523

RESUMEN

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.


Asunto(s)
Linfoma Folicular/diagnóstico , Linfoma Folicular/genética , Proteínas Proto-Oncogénicas c-myc/genética , Translocación Genética , Anciano , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 18 , Cromosomas Humanos Par 8 , Análisis Citogenético , Femenino , Humanos , Masculino , Pronóstico , Resultado del Tratamiento
17.
Toxicol Appl Pharmacol ; 179(2): 89-97, 2002 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11884241

RESUMEN

Dichloromethane (DCM) is a hepatic and pulmonary carcinogen in mice exposed to high doses by inhalation. It has been shown previously that the incidence of liver and lung tumors does not increase in rats or hamsters exposed to the dihaloalkane under conditions similar to those that produced tumors in mice. The biological consequences of DCM exposure to humans is therefore uncertain. The carcinogenic effects of DCM in the mouse are caused by the interaction with DNA of a glutathione (GSH) conjugate that is produced by the class theta glutathione S-transferase T1-1 (GST T1-1). The species specificity is thought to be due to the greater amount of transferase activity in mouse target organs and specific nuclear localization of GST T1-1 in target cells. This paper directly compares the relative capacity and locality of DCM activation in mouse and human tissues. The results show that mouse GST T1-1 is more efficient in catalyzing the conjugation of DCM with GSH than the orthologous human enzyme. In addition, the mouse expresses higher levels of the transferase than humans in hepatic tissue. Histochemical analysis confirmed the presence of GST T1-1 in the nucleus of mouse liver cells. However, in human liver GST T1-1 was detected in bile duct epithelial cells and hepatocyte nuclei but was also present in the cytoplasm. Taking this information into account, it is unlikely that humans have a sufficiently high capacity to activate DCM for this compound to be considered to represent a carcinogenic risk.


Asunto(s)
Carcinógenos/toxicidad , Glutatión Transferasa/metabolismo , Hígado/enzimología , Cloruro de Metileno/toxicidad , Animales , Catálisis , Electroforesis en Gel de Poliacrilamida , Escherichia coli/metabolismo , Glutatión Transferasa/biosíntesis , Glutatión Transferasa/genética , Humanos , Inmunohistoquímica , Indicadores y Reactivos , Cinética , Ratones , Ratones Endogámicos , Proteínas Recombinantes/química , Especificidad de la Especie
18.
Genes Chromosomes Cancer ; 41(4): 405-9, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15390188

RESUMEN

Combined immunofluorescence (IF) and fluorescence in situ hybridization (FISH) on formalin-fixed, paraffin-embedded tissue sections were used to examine lymph node tissue from two patients diagnosed with T-cell lymphoma with Epstein-Barr virus (EBV)-infected B-cell blasts. The majority of cells within the samples comprised T-cells staining positively for CD3. In addition, both patients had a population of large pleiomorphic cells that were positive for the B-cell marker CD20 and for EBV LMP-1. Standard PCR clonality testing of the nodes revealed both immunoglobulin heavy chain (IGH) and T-cell receptor (TCR) clonal rearrangements in one patient, although in the other case monoclonality was demonstrated only for TCRG. Cytogenetics of cultured lymphocytes from nodal tissue revealed two apparently unrelated abnormal clones in both patients. Combined IF and FISH revealed that these phenomena reflected two abnormal populations of B- and T-cells rather than reactive B-cell hyperplasia or biphenotypic evolution from a common ancestral lymphoma. True B-cell malignancy probably emerged within a preexisting but unrelated T-cell lymphoma. This is the first study to relate the phenotype of the abnormal cells in such cases to specific clonal populations of cells, and it demonstrates a method that may easily be introduced into a diagnostic cytogenetics laboratory with access to standard pathology laboratory resources.


Asunto(s)
Linfocitos B/patología , Herpesvirus Humano 4 , Ganglios Linfáticos/patología , Linfoma de Células T/patología , Antígenos CD20/metabolismo , Linfocitos B/metabolismo , Linfocitos B/virología , Complejo CD3/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/virología , Linfoma de Células T/metabolismo , Linfoma de Células T/virología , Adhesión en Parafina , Proteínas de la Matriz Viral/metabolismo
19.
Mol Cell Proteomics ; 3(6): 534-47, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-14967811

RESUMEN

The esophageal epithelium is subject to damage from bile acid reflux that promotes normal tissue injury resulting in the development of Barrett's epithelium. There is a selection pressure for mutating p53 in this preneoplastic epithelium, thus identifying a physiologically relevant model for discovering novel regulators of the p53 pathway. Proteomic technologies were used to identify such p53 regulatory factors by identifying proteins that were overexpressed in Barrett's epithelium. A very abundant polypeptide selectively expressed in Barrett's epithelium was identified as anterior gradient-2. Immunochemical methods confirmed that anterior gradient-2 is universally up-regulated in Barrett's epithelium, relative to normal squamous tissue derived from the same patient. Transfection of the anterior gradient-2 gene into cells enhances colony formation, similar to mutant oncogenic p53 encoded by the HIS175 allele, suggesting that anterior gradient-2 can function as a survival factor. Deletion of the C-terminal 10 amino acids of anterior gradient-2 neutralizes the colony enhancing activity of the gene, suggesting a key role for this domain in enhancing cell survival. Constitutive overexpression of anterior gradient-2 does not alter cell-cycle parameters in unstressed cells, suggesting that this gene is not directly modifying the cell cycle. However, cells overexpressing anterior gradient-2 attenuate p53 phosphorylation at both Ser(15) and Ser(392) and silence p53 transactivation function in ultraviolet (UV)-damaged cells. Deletion of the C-terminal 10 amino acids of anterior gradient-2 permits phosphorylation at Ser(15) in UV-damaged cells, suggesting that the C-terminal motif promoting colony survival also contributes to suppression of the Ser(15) kinase pathway. These data identify anterior gradient-2 as a novel survival factor whose study may shed light on cellular pathways that attenuate the tumor suppressor p53.


Asunto(s)
Esófago de Barrett/metabolismo , Daño del ADN , Silenciador del Gen , Neoplasias Intestinales/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas de Xenopus/fisiología , Secuencia de Aminoácidos , Esófago de Barrett/patología , Ciclo Celular , Supervivencia Celular , Ensayo de Unidades Formadoras de Colonias , Electroforesis en Gel Bidimensional , Células Epiteliales/citología , Células Epiteliales/metabolismo , Humanos , Neoplasias Intestinales/patología , Espectrometría de Masas , Metaplasia/metabolismo , Metaplasia/patología , Datos de Secuencia Molecular , Fosforilación , Proteína Disulfuro Isomerasas , Homología de Secuencia de Aminoácido , Proteína p53 Supresora de Tumor/genética , Rayos Ultravioleta
20.
Anticancer Drugs ; 15(10): 991-6, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15514569

RESUMEN

The efficacy of MDI-301, a non-toxic novel synthetic retinoid, was found to be equivalent to the natural 9-cis-retinoic acid (RA) in vitro against estrogen-dependent MCF7 and T47D breast cancer cell lines which express RA receptor (RAR) alpha. Both retinoids also showed similar efficacy against established PC-3 prostate carcinoma xenografts. MCF7 tumor xenografts showed a reduction in tumor growth of 48% without systemic side-effects upon treatment with MDI-301 compared with MCF7 controls. Tumor xenografts derived from MDA-MB-231, an estrogen-independent breast cancer cell line that expresses low levels of RARalpha, were unresponsive. This study demonstrates that MDI-301 is as efficacious as 9-cis-RA against cancer cells with RARalpha, with no signs of toxicity in vivo, making it a potential candidate for cancer therapy.


Asunto(s)
Antineoplásicos/farmacología , Retinoides/farmacología , Alitretinoína , Animales , Neoplasias de la Mama , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Desnudos , Neoplasias de la Próstata , Receptores de Ácido Retinoico/biosíntesis , Receptor alfa de Ácido Retinoico , Tretinoina/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
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