RESUMEN
To examine the relationship of chromosome 1 copy number to melanocytic tumorigenesis, interphase cytogenetic analysis of 1q12 satellite III DNA was performed on the spectrum of melanocytic lesions comprising Clark's tumor progression model. Results showed increased copy number in a "step off" pattern between melanoma in-situ and the intraepidermal component of invasive melanoma rather than a progression between each lesional group. These findings support Clark's concept of independent clonal expansion of a cell population giving rise to the vertical growth phase and further demonstrates increased chromosome 1 copy number as a late event in melanoma tumor progression.
Asunto(s)
Aneuploidia , Cromosomas Humanos Par 1/genética , ADN Satélite/genética , Interfase , Melanoma/genética , Neoplasias Cutáneas/genética , Análisis de Varianza , Análisis Citogenético , Progresión de la Enfermedad , Síndrome del Nevo Displásico/genética , Humanos , Hibridación in Situ , Melanoma/patología , Melanoma/secundario , Invasividad Neoplásica , Nevo Pigmentado/genética , Estudios Retrospectivos , Neoplasias Cutáneas/patologíaRESUMEN
BACKGROUND: The purine nucleoside phosphorylase inhibitor peldesine is a new agent being evaluated as a T-cell inhibitor. OBJECTIVE: We attempted to determine the efficacy of peldesine (BCX-34) in a 1% dermal cream formulation as a treatment for cutaneous T-cell lymphoma (CTCL). METHODS: Ninety patients with patch and plaque phase CTCL, histologically confirmed by a referee dermatopathologist, were enrolled in a randomized, double-blind, placebo-controlled study. BCX-34 dermal cream 1% or the vehicle cream (as a placebo control) was applied twice daily to the entire skin surface for up to 24 weeks. Efficacy of the topical therapy was assessed in terms of complete or partial (> or = 50%) clearing of patches and plaques. RESULTS: Of the 89 patients able to be examined, 43 received BCX-34 and 46 received the placebo vehicle cream. One patient withdrew early and was not analyzed. The two groups were well balanced for potential prognostic factors. A total of 28% (12/43) of the patients treated with BCX-34 showed a response, but 24% (11/46) of patients who received vehicle also responded (P =.677). CONCLUSION: Although BCX-34 dermal cream 1% was not significantly better than the control as therapy for patch and plaque-phase CTCL, this appears to be the first published placebo-controlled trial evaluating treatment for CTCL. Whether the vehicle cream has more than a placebo therapeutic effect is unclear. The relatively high (24%) placebo response rate should be kept in mind in assessing other treatments for early-stage CTCL.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Guanina/análogos & derivados , Guanina/farmacología , Linfoma Cutáneo de Células T/tratamiento farmacológico , Administración Cutánea , Adulto , Anciano , Método Doble Ciego , Inhibidores Enzimáticos/administración & dosificación , Femenino , Guanina/administración & dosificación , Humanos , Linfoma Cutáneo de Células T/patología , Masculino , Persona de Mediana Edad , Placebos , Resultado del TratamientoRESUMEN
BACKGROUND: It remains unclear which patients with melanoma will benefit most from lymphatic mapping and sentinel lymphadenectomy. The purpose of this study is to determine whether primary melanoma histopathologic features could be applied to predict sentinel node status. METHODS: One hundred twelve patients underwent sentinel node biopsy between May 1995 and August 1999. Reported histologic features were assessed for predictive value by univariate and multivariate logistic regression. RESULTS: The sentinel node was located successfully in 105 of the 112 patients (94%). Twenty-one of these 105 patients (20%) had sentinel nodes that were positive for metastatic disease. Multivariate analyses revealed that tumor thickness greater than 1.5 mm (P = 0.01), ulceration (P <0.01), and lymphovascular invasion (P = 0.05) predicted the presence of micrometastases. CONCLUSIONS: The presence of unfavorable histopathology such as ulceration and lymphovascular invasion may identify a group of patients with thin melanomas who would benefit from sentinel lymphadenectomy.
Asunto(s)
Melanoma/patología , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/patología , Femenino , Humanos , Modelos Logísticos , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Melanoma/secundario , Persona de Mediana Edad , Valor Predictivo de las PruebasRESUMEN
BACKGROUND: Basal cell carcinoma (BCC) is the most common cutaneous malignancy. Surgical experience and physician specialty may affect the outcome quality of surgical excision of BCC. METHODS: We performed a multicenter retrospective study of BCC excisions submitted to the respective Departments of Pathology at 4 major university medical centers. Our outcome measure was presence of histologic evidence of tumor present in surgical margins of excision specimens (incomplete excision). Clinician experience was defined as the number of excisions that a clinician performed during the study interval. The analytic sample pool included 1459 tumors that met all inclusion and exclusion criteria. Analyses included univariate and multivariate techniques involving the entire sample and separate subsample analyses that excluded 2 outlying dermatologists. RESULTS: Tumor was present at the surgical margins in 243 (16.6%) of 1459 specimens. A patient's sex, age, and tumor size were not significantly related to the presence of tumor in the surgical margin. Physician experience did not demonstrate a significant difference either in the entire sample (P <.09) or in the subsample analysis (P >.30). Tumors of the head and neck were more likely to be incompletely excised than truncal tumors in all the analyses (P <.03). Compared with dermatologists, otolaryngologists (P <.02) and plastic surgeons (P <.008) were more likely to incompletely excise tumors; however, subsample analysis for plastic surgeons found only a trend toward significance (P <.10). Dermatologists and general surgeons did not differ in the likelihood of performing an incomplete excision (P >.4). CONCLUSION: The physician specialty may affect the quality of care in the surgical management of BCC.
Asunto(s)
Carcinoma Basocelular/cirugía , Medicina , Neoplasias Cutáneas/cirugía , Especialización , Anciano , Competencia Clínica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasia Residual , Oportunidad Relativa , Calidad de la Atención de Salud , Estudios RetrospectivosRESUMEN
Cutaneous Crohn disease, sometimes called metastatic Crohn disease or Crohn disease with cutaneous involvement, is a rare complication of Crohn disease in which granulomatous lesions involve skin separated from gastrointestinal lesions by normal tissue. We report two cases of cutaneous Crohn disease presenting in young males with erythematous, nontender swelling of the scrotum. One of the young males presented erythematous, nontender swelling of the penis as well. In one case, cutaneous Crohn disease represented the primary presentation. The original biopsy in this case showed unusual areas of degeneration of dermal connective tissue forming cystic cavities. The diagnostic biopsies in both cases showed sarcoidal granulomas with an associated superficial and deep perivascular mixed infiltrate including eosinophils. On endoscopy, both patients showed lesions of active Crohn disease in the colon. Because changes that would suggest cutaneous Crohn disease may not be present on the initial biopsy, unusual presentations and negative cultures may warrant a second biopsy. A high index of suspicion and open communication with the clinician are essential to diagnose this disease.
Asunto(s)
Enfermedad de Crohn/patología , Enfermedades del Pene/patología , Enfermedades de la Piel/patología , Enfermedades Testiculares/patología , Adolescente , Adulto , Colitis/diagnóstico , Humanos , MasculinoRESUMEN
The adjuvant treatment of high-risk malignant melanoma remains problematic. Previously we reported moderate success in the treatment of metastatic disease using tamoxifen, cisplatin, dacarbazine and carmustine. Based upon data that suggested tamoxifen and cisplatin were the active agents in this regimen, we initiated a phase II trial of this combination in the adjuvant setting. We treated 153 patients with 4 cycles of tamoxifen (160 mg day(-1), days 1-7) and cisplatin (100 mg m(-2), day 2) for 28-day intervals. Patients received an anti-nausea regimen of dexamethasone with ondansetron or granisetron. During the first 2 years of follow-up, patients were evaluated every 2 months with a history, physical exam, laboratory work and computed tomography scans of the chest, abdomen and pelvis every 4 months. Thereafter, patients were evaluated every 3 months and radiographic studies were performed if necessary. Currently, with a median follow-up of 36 months, the disease-free survival (DFS) is 68.4% and overall survival (OS) is 84.5%. Kaplan-Meier analysis predicts a 5-year DFS of 62% with an OS of 79%. Relapses after 20 months have been rare. No effect of gender or number of positive lymph nodes was noted, however, stage of disease prior treatment was a factor. The major toxicity proved to be gastrointestinal in nature with nausea the most prevalent symptom. Minimal renal, haematologic and neurologic toxicity occurred. These preliminary results suggest that there is a positive impact of tamoxifen and cisplatin on both the DFS and OS of high-risk malignant melanoma patients. The 5-year projected DFS and OS compare favourably with those reported for the ECOG 1684 trial and warrant confirmation in a prospective randomized trial.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Adulto , Anciano , Antieméticos/uso terapéutico , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Terapia Combinada , Dexametasona/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Granisetrón/uso terapéutico , Humanos , Tablas de Vida , Metástasis Linfática , Masculino , Melanoma/mortalidad , Melanoma/patología , Melanoma/cirugía , Persona de Mediana Edad , Náusea/inducido químicamente , Náusea/prevención & control , Metástasis de la Neoplasia , Estadificación de Neoplasias , Ondansetrón/uso terapéutico , Pronóstico , Riesgo , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Análisis de Supervivencia , Tamoxifeno/administración & dosificación , Tamoxifeno/efectos adversos , Resultado del Tratamiento , Vómitos/inducido químicamente , Vómitos/prevención & controlRESUMEN
Iontophoresis is a process that uses electrical current to increase the flux of ionized substances through tissue. Iontophoresis has been used in rehabilitation to decrease inflammation and pain using dexamethasone and lidocaine. In 1993, Chang et al. reported visual improvements in the lesions of nine patients diagnosed with basal cell carcinoma (BCC) following iontophoresis of cisplatin. The present case report describes the successful treatment of a 67-year-old male with a histologically confirmed BCC on his upper anterolateral left leg. The treatment consisted of four cycles of five successive days of cisplatin iontophoresis, with a 2-week rest period between cycles. The cisplatin solution (5 mL at 1 mg/mL) was used in combination with epinephrine hydrochloride. The effectiveness of the treatment was confirmed by post-treatment biopsies, which revealed granulation tissue scarring without evidence of BCC. Measurements of cellular proliferation were monitored immunohistochemically with Ki-67 and cell cycle distribution analyzed by flow cytometry.
Asunto(s)
Antineoplásicos Alquilantes/administración & dosificación , Carcinoma Basocelular/tratamiento farmacológico , Cisplatino/administración & dosificación , Iontoforesis , Neoplasias Cutáneas/tratamiento farmacológico , Anciano , Antineoplásicos Alquilantes/uso terapéutico , Carcinoma Basocelular/química , Carcinoma Basocelular/patología , Ciclo Celular , Cisplatino/uso terapéutico , Esquema de Medicación , Evaluación de Medicamentos , Epinefrina/administración & dosificación , Citometría de Flujo , Humanos , Antígeno Ki-67/análisis , Pierna , Masculino , Proteínas de Neoplasias/análisis , Neoplasias Cutáneas/química , Neoplasias Cutáneas/patologíaRESUMEN
The biological nature of Spitz nevi/tumors and their diagnostic distinction from, or relationship to, melanoma remain unresolved issues. In this report, a series of 30 melanocytic lesions removed from 28 patients, including atypical Spitz nevi/tumors and metastasizing Spitzoid tumors/melanomas, were evaluated by a panel of dermatopathologists to evaluate interobserver diagnostic concordance and to assess the prognostic power of histological criteria. For inclusion in the study, each lesion had to display some criteria for the Spitz nevus, and in addition one of the following was required: (1) definitive clinical outcome such as metastasis or death of disease, or (2) long-term follow-up if the patient remained disease free. Each lesion was reviewed independently and blinded as to the clinical data by 10 pathologists, who categorized them as (1) typical Spitz nevus/tumor, (2) atypical Spitz nevus/tumor, (3) melanoma, (4) tumor with unknown biological potential, or (5) other melanocytic lesion. There was limited discussion of criteria before the review. Evaluation of 17 Spitzoid lesions yielded no clear consensus as to diagnosis; in only one case did six or more pathologists agree on a single category, regardless of clinical outcome. Notably, however, some lesions that proved fatal were categorized by most observers as either Spitz nevi or atypical Spitz tumors. Conversely, seven or more pathologists scored 13 lesions as melanoma. These results illustrate (1) substantial diagnostic difficulties posed by many Spitz tumors, especially those with atypical features, even among experts, and (2) the lack of objective criteria for their distinction from melanoma and for gauging their malignant potential. Nevertheless, our observations do suggest that a biological relationship exists between the Spitz nevus/tumor and melanoma.
Asunto(s)
Melanoma/patología , Nevo de Células Epitelioides y Fusiformes/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Melanoma/diagnóstico , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Nevo de Células Epitelioides y Fusiformes/diagnóstico , Variaciones Dependientes del Observador , Pronóstico , Neoplasias Cutáneas/diagnósticoRESUMEN
"Clark's nevi" is the name we apply to lesions that have been referred to in the past as dysplastic nevi or nevi with architectural and/or cytologic atypia. Our criteria for this histopathologic diagnosis include such architectural features as: (1) uneven distribution of melanocytes along the dermoepidermal junction; (2) irregularly spaced junctional nests that sometimes bridge between rete; and (3) ill-defined margins often characterized by a lentiginous growth pattern. If dermal nests are present, the junctional component usually extends laterally for some distance beyond the dermal nests. When there is cytologic atypia, it involves scattered melanocytes. Clark's nevi are of doubtful significance if few in number and occurring in a young patient in whom there is no family history of melanoma. When many are found in a patient with a family history of melanoma, their presence serves as a marker for dysplastic nevus syndrome (familial atypical mole-melanoma syndrome). When Clark's nevi develop in patients older than 40 or 50 years of age who have no family history of melanoma, their significance is less clear. However, they might signify a defect in those mechanisms that normally control formation and growth of melanocytic neoplasms.
Asunto(s)
Nevo , Neoplasias Cutáneas , Diagnóstico Diferencial , Humanos , Nevo/diagnóstico , Nevo/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patologíaRESUMEN
BACKGROUND: The histologic discrimination of melanoma in situ of sun-damaged skin (MIS) from chronically sun-damaged skin (SDS) can sometimes be difficult using accepted criteria. OBJECTIVE: We evaluated these entities by means of morphometry and multifactorial analysis. METHODS: We measured the number and area of melanocyte nuclei, melanocyte nucleoli, stratum spinosum keratinocyte nuclei, and papillary dermal lymphocyte nuclei from hematoxylin-eosin-stained slides representing 38 cases of MIS and 18 cases of SDS matched for age, sex, and site with a high-resolution digital imaging and analysis system. RESULTS: Multiple logistic regression analysis correctly classified 100% of the cases using the number of melanocytes per 0.5 mm and the maximum melanocyte nuclear area divided by the maximum keratinocyte nuclear area. The strongest results were achieved measuring approximately 1 mm of epidermis. CONCLUSION: Morphometry and multifactorial analysis can distinguish MIS from SDS. Morphometric analysis of melanocytic proliferations may be useful at the margins of surgical resections.
Asunto(s)
Peca Melanótica de Hutchinson/patología , Melanoma/patología , Neoplasias Cutáneas/patología , Quemadura Solar/patología , Anciano , Enfermedad Crónica , Diagnóstico Diferencial , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Piel/patología , Estadísticas no ParamétricasRESUMEN
Individuals affected with tuberous sclerosis complex (TSC) develop several benign and malignant tumors at increased frequency, including astrocytomas. Tuberin, the protein product of the tuberous sclerosis complex-2 (TSC2) tumor suppressor gene, has been shown to directly inhibit cell growth and is expressed at high levels in normal central nervous system neurons and astrocytes. To determine whether TSC2 RNA and protein are reduced in astrocytomas from individuals without tuberous sclerosis, reverse transcriptase-polymerase chain reaction and immunoblotting analyses were performed on 49 adult astrocytomas, 10 pediatric astrocytomas, and 13 ependymomas. Eighteen of 40 (45%) high-grade (World Health Organization [WHO] grade III/IV) astrocytomas and 4 of 8 (50%) adult low-grade (WHO grade II) astrocytomas demonstrated reduced or absent TSC2 expression, including 1 giant cell astrocytoma, whereas none of the 10 pediatric low-grade astrocytomas analyzed showed a reduction in TSC2 expression. Reduced or absent tuberin was observed in 2 of 6 (33%) ependymomas analyzed. These data demonstrate, for the first time, that reduced or absent TSC2 expression may represent one of the critical genetic events associated with the development of sporadic adult, but not pediatric, astrocytomas.
Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Ependimoma/genética , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Proteínas Represoras/biosíntesis , Adulto , Factores de Edad , Astrocitoma/metabolismo , Astrocitoma/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Niño , Cartilla de ADN , Ependimoma/metabolismo , Ependimoma/patología , Exones , Humanos , Reacción en Cadena de la Polimerasa , Biosíntesis de Proteínas , ARN Mensajero/biosíntesis , Proteínas Represoras/genética , Transcripción Genética , Esclerosis Tuberosa/genética , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de TumorRESUMEN
The tuberous sclerosis-2 (TSC2) gene is linked to tuberous sclerosis (TSC), a dominantly inherited genetic syndrome in which inactivation of the normal TSC2 allele is associated with the development of mostly benign tumors and focal dysplasias. TSC2 encodes the protein tuberin, which is a widely expressed 180-kd polypeptide that exhibits specific GTPase activating activity toward Rap1 in vitro and co-localizes with Rap1 in cultured cells. In this study, we have performed immunohistochemical analyses, using affinity-purified anti-tuberin antibodies, to study the distribution of tuberin in a panel of normal human organs that are commonly affected by TSC. Cryosections indicated that tuberin is widely expressed at low levels. More intense staining of tuberin, in the cryosections and in paraffin sections, was observed in the small blood vessels of many organs, including the kidney, skin, and adrenal gland. High levels of tuberin were also detected in cortical neurons and cerebellar Purkinje cells. These findings imply that loss-of-function mutations in TSC2 might lead to the development of highly vascularized tumors, subcortical tubers, and focal atrophy of the cerebellar cortex, which are features commonly associated with TSC. Moreover, Rap1 was also found to be highly expressed in many of the same cells that contained high levels of tuberin, suggesting a functional interaction between tuberin and Rap1 in these tissues.
Asunto(s)
Proteínas de Unión al GTP/biosíntesis , Genes Supresores de Tumor , Proteínas Represoras/biosíntesis , Proteínas Represoras/genética , Esclerosis Tuberosa/genética , Corteza Cerebral/química , Proteínas de Unión al GTP/química , Humanos , Inmunohistoquímica , Riñón/química , Miocardio/química , Proteínas Represoras/química , Piel/química , Esclerosis Tuberosa/patología , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de Tumor , Proteínas de Unión al GTP rapAsunto(s)
Melanoma/patología , Melanosis/patología , Neoplasias Cutáneas/patología , Diagnóstico Diferencial , Femenino , Enfermedades de los Genitales Femeninos/patología , Enfermedades de los Genitales Masculinos/patología , Humanos , Lentigo/patología , Masculino , Melanocitos/patología , Nevo/patología , Nevo Azul/patología , Nevo Pigmentado/patología , Enfermedades de la Piel/patologíaRESUMEN
Tuberous sclerosis (TSC), an autosomal dominant disorder, is characterized by malformations, hamartomas and tumors in various organs including the brain. TSC is genetically linked to two loci: TSC1 on chromosome 9q34 and TSC2 on 16p13.3. TSC2 has been cloned, sequenced and encodes a protein (tuberin) which functions as a tumor suppressor. We have analyzed the distribution of TSC2 mRNA and tuberin in the brains of TSC patients and non-affected individuals using both autopsy and biopsy material. High levels of transcript and protein expression were observed in choroid plexus epithelium, ependymal cells, most brainstem and spinal cord motor neurons, Purkinje cells and the external granule cell layer of the cerebellum in both TSC and control cases. Individual balloon cells from TSC patients showed very faint expression while other glia showed no expression of either transcript or tuberin. Neocortical and hippocampal neurons expressed high levels of TSC2 transcript, but only modest levels of tuberin. The internal granule cell layer of the cerebellum expressed abundant transcript but low levels of tuberin. These observations suggest either that tuberin expression is controlled at the level of both transcription and translation or the antibody and in-situ hybridization recognize different splice variants of the TSC2 gene. In TSC patients, dysmorphic cytomegalic neurons expressed high levels of tuberin and transcript, particularly when in an 'ectopic' location. Individual cells within subependymal giant cell astrocytomas (SEGAs) and hamartomas from TSC patients expressed moderate to high levels of TSC2 transcript and tuberin. While the TSC2 transcript is widely expressed primarily within neurons, tuberin is demonstrable primarily within dysplastic/cytomegalic cells of the cortex and subependymal hamartomas/SEGAs. CNS expression of tuberin is unique in that primarily non-dividing cells express it in this location, whereas extra-CNS expression of tuberin is mainly found in actively proliferating cell types such as epithelium.
Asunto(s)
Encéfalo/metabolismo , Proteínas Represoras/biosíntesis , Esclerosis Tuberosa/genética , Adolescente , Adulto , Encéfalo/citología , Encéfalo/patología , Niño , Preescolar , Mapeo Cromosómico , Cromosomas Humanos Par 16 , Cromosomas Humanos Par 9 , Femenino , Feto , Genes Supresores de Tumor , Humanos , Inmunohistoquímica , Hibridación in Situ , Lactante , Embarazo , ARN Mensajero/análisis , Proteínas Represoras/análisis , Proteínas Represoras/genética , Transcripción Genética , Esclerosis Tuberosa/metabolismo , Esclerosis Tuberosa/patología , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de TumorRESUMEN
Tuberin is the protein product of the tuberous sclerosis-2 (TSC2) gene, which is associated with tuberous sclerosis (TSC), a human genetic syndrome characterized by the development of tumors in a variety of tissues. We have previously shown that tuberin is a widely expressed 180 kDa protein which exhibits specific GTPase activating activity in vitro towards the Ras-related Rap1 protein. In this study we have used affinity-purified antibodies against tuberin to analyse its expression in human and rat tissues and to examine its subcellular localization. Tuberin expression was detected in all adult human tissues tested, with the highest levels found in brain, heart and kidney, organs that are commonly affected in TSC patients. By contrast, in adult rats the highest levels of tuberin were found in brain, liver and testis. Indirect immunofluorescence of tuberin in various cultured cell lines revealed a punctate, mostly perinuclear staining pattern. Double-indirect immunofluorescence analysis with anti-tuberin sera and antisera against known Golgi markers (mannosidase-II and furin) revealed that the staining of tuberin was consistent with its localization in the stacks of the Golgi apparatus. In support of this, treatment of cells with brefeldin A, a drug known to cause disassembly of the Golgi apparatus, abolished the perinuclear staining of tuberin. Moreover, conventional and confocal immunofluorescence demonstrated co-localization of tuberin with Rap1, which has previously been localized to the Golgi apparatus. The co-localization of tuberin and Rap1 in vivo strengthens the likelihood that the in vitro catalytic activity of tuberin toward Rap1 plays a physiologically relevant role in the tumor suppressor function of tuberin.
Asunto(s)
Proteínas de Unión al GTP/metabolismo , Aparato de Golgi/metabolismo , Proteínas Represoras/metabolismo , Animales , Anticuerpos , Brefeldino A , Células Cultivadas/efectos de los fármacos , Cromatografía de Afinidad , Ciclopentanos/farmacología , Técnica del Anticuerpo Fluorescente Indirecta , Proteínas de Unión al GTP/análisis , Proteínas de Unión al GTP/inmunología , Aparato de Golgi/química , Humanos , Microscopía Confocal , Inhibidores de la Síntesis de la Proteína/farmacología , Conejos , Ratas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Represoras/análisis , Proteínas Represoras/inmunología , Distribución Tisular , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de Tumor , Proteínas de Unión al GTP rapRESUMEN
The Tsc2 gene, which is mutationally inactivated in the germ line of some families with tuberous sclerosis, encodes a large, membrane-associated GTPase activating protein (GAP) designated tuberin. Studies of the Eker rat model of hereditary cancer strongly support the role of Tsc2 as a tumor suppressor gene. In this study, the biological activity of tuberin was assessed by expressing the wild-type Tsc2 gene in tumor cell lines lacking functional tuberin and also in rat fibroblasts with normal levels of endogenous tuberin. The colony forming efficiency of Eker rat-derived renal carcinoma cells was significantly reduced following reintroduction of wild-type Tsc2. Tumor cells expressing the transfected Tsc2 gene became more anchorage-dependent and lost their ability to form tumors in severe combined immunodeficient mice. At the cellular level, restoration of tuberin expression caused morphological changes characterized by enlargement of the cells and increased contact inhibition. As with the full-length Tsc2 gene, a clone encoding only the C terminus of tuberin (amino acids 1049-1809, including the GAP domain) was capable of reducing both colony formation and in vivo tumorigenicity when transfected into the Eker rat tumor cells. In normal Rat1 fibroblasts, conditional overexpression of tuberin also suppressed colony formation and cell growth in vitro. These results provide direct experimental evidence for the tumor suppressor function of Tsc2 and suggest that the tuberin C terminus plays an important role in this activity.
Asunto(s)
Carcinoma/genética , Genes Supresores de Tumor , Neoplasias Renales/genética , Fragmentos de Péptidos/genética , Proteínas Represoras/genética , Esclerosis Tuberosa/genética , Animales , Carcinoma/etiología , Carcinoma/patología , Línea Celular , Modelos Animales de Enfermedad , Fibroblastos , Neoplasias Renales/etiología , Neoplasias Renales/patología , Ratones , Ratones SCID , Mutación , Fragmentos de Péptidos/biosíntesis , Ratas , Proteínas Represoras/biosíntesis , Transfección , Esclerosis Tuberosa/etiología , Esclerosis Tuberosa/patología , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de TumorRESUMEN
BACKGROUND: The possible association of silicone breast implants and disease is a subject of continuous debate and concern. OBJECTIVE: Our purpose was to examine microscopically and ultrastructurally the periprosthetic fibrous capsules and reconstruction scars of women with silicone breast implants. METHODS: Representative samples from the periprosthetic capsules and reconstruction scars from six women with silicone breast implants were examined by a variety of light microscopy techniques, transmission electron microscopy, and electron probe microanalysis. RESULTS: Silicone globules of various sizes were identified in every periprosthetic capsule and reconstruction scar. CONCLUSION: Extrusion and seeding of the incision tract during surgery most likely accounts for the presence of silicone in the reconstruction scar specimens. This observation suggests that the identification of silicone in the reconstruction scars of women with silicone breast implants does not necessarily implicate rupture of the silicone breast implant with systemic dissemination of silicone gel.
Asunto(s)
Implantes de Mama , Cicatriz/patología , Mamoplastia , Siliconas/metabolismo , Cicatriz/metabolismo , Tejido Conectivo/metabolismo , Tejido Conectivo/patología , Tejido Conectivo/cirugía , Tejido Conectivo/ultraestructura , Procedimientos Quirúrgicos Dermatologicos , Microanálisis por Sonda Electrónica , Femenino , Cuerpos Extraños/metabolismo , Cuerpos Extraños/patología , Humanos , Mamoplastia/métodos , Microscopía Electrónica , Microscopía de Polarización , Falla de Prótesis , Siliconas/análisis , Piel/metabolismo , Piel/patología , Piel/ultraestructuraRESUMEN
We review the clinical features, histopathology, and immunohistochemistry in three cases of eosinophilic histiocytosis, comparing lymphomatoid papulosis and eosinophilic histiocytosis. Each of the patients presented with self-healing recurrent papules and ulcerative nodules that were associated with pruritus. Disease duration was 5 months to 9 years. Histologically, the lesions demonstrated spongiosis and lymphocytic exocytosis, epidermal hyperplasia, papillary dermal edema, and a superficial and deep mixed perivascular inflammatory infiltrate. The infiltrate showed numerous eosinophils, histiocytoid cells, lymphocytes, and large mononuclear cells with atypical hyperchromatic nuclei. Most of the lymphocytes and large mononuclear cells with atypical nuclei marked with UCHL-1 (T-cell marker). The histiocytoid cells marked with S-100 and were dendritic both in the epidermis and the dermis. Eosinophilic histiocytosis appears to differ from classic lymphomatoid papulosis. It presents with recurrent papules and nodules associated with marked pruritus. Eosinophilic histiocytosis uniformly has more eosinophils and does not have the Reed-Sternberg cells often observed in lymphomatoid papulosis type A. Eosinophilic histiocytosis does not have cells that mark with Ki-1 and shows numerous S-100-positive histiocytoid cells that are most likely Langerhans cells, unlike lymphomatoid papulosis. However, eosinophilic histiocytosis may be an unusual Ki-1-negative variant of lymphomatoid papulosis with histopathologic changes not typical of type A or type B. In addition, eosinophilic histiocytosis lacks multinucleated histiocytes and the atypical histiocyte with a reniform nucleus, findings that are characteristic of histiocytosis X. Further studies are needed to define the pathophysiology and prognosis of this apparently distinct entity more accurately.
Asunto(s)
Eosinofilia/patología , Histiocitosis/patología , Enfermedades Cutáneas Papuloescamosas/patología , Adulto , Anciano , Anciano de 80 o más Años , Cromatina/ultraestructura , Células Dendríticas/patología , Edema/patología , Eosinofilia/metabolismo , Eosinófilos/patología , Epidermis/patología , Exocitosis , Femenino , Histiocitosis/metabolismo , Humanos , Hiperplasia , Inmunohistoquímica , Leucocitos Mononucleares/patología , Linfocitos/patología , Papulosis Linfomatoide/patología , Masculino , Prurito/patología , Recurrencia , Proteínas S100/análisis , Enfermedades Cutáneas Papuloescamosas/metabolismo , Linfocitos T/patologíaRESUMEN
Caterpillar bodies are eosinophilic, periodic acid-Schiff (PAS)-positive globules arranged in a linear fashion in the epidermis overlying subepidermal blisters of porphyria cutanea tarda (Am J Dermatopathol 1993;15:199-202). We retrospectively studied by transmission electron microscopy nine cases of porphyria cutanea tarda (PCT) that demonstrated caterpillar bodies. We identified three components of the eosinophilic bodies: degenerating keratinocytes, colloid bodies, and basement membrane bodies. The colloid bodies consisted of whorled masses of filaments containing degenerating melanosomes, vacuoles, mitochondria, and desmosomes. Basement membrane bodies were composed of convoluted basement membrane material and associated collagen. Both colloid and basement membrane bodies were often associated with degenerating keratinocytes, were located both intra-and extracellularly, and were occasionally fused to one another. We believe that caterpillar bodies are a combination of degenerating keratinocytes, colloid bodies, and basement membrane bodies formed by repeated blistering and reepithelialization with transepidermal migration. Furthermore, we believe that caterpillar bodies are a diagnostic clue for the diagnosis of PCT.
Asunto(s)
Coloides/química , Cuerpos de Inclusión/patología , Cuerpos de Inclusión/ultraestructura , Porfiria Cutánea Tardía/patología , Membrana Basal/química , Membrana Basal/patología , Membrana Basal/ultraestructura , Humanos , Inmunohistoquímica , Queratinocitos/patología , Queratinocitos/ultraestructura , Porfiria Cutánea Tardía/diagnóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: Seborrheic keratoses (SKs) can be seen in association with cancers. OBJECTIVE: Our study was designed to demonstrate the occurrence of concomitant SKs and nonmelanoma skin cancers, as well as to correlate their histological types and clinical locations. The study was not intended to be an epidemiologic survey. METHODS: We prospectively collected 108 completely excised SKs, examined them microscopically, categorized them, and correlated the clinical site, histological type, and determined the incidence of concomitant malignancy. RESULTS: Of the 108 SKs studied, 71 were acanthotic, 27 hyperkeratotic, and 10 reticulated. The incidence of associated nonmelanoma cancers was 4.6%. All malignancies were squamous cell carcinomas and were on sun-exposed skin. Three of the five malignancies arose in conjunction with reticulated SKs. CONCLUSIONS: The incidence of nonmelanoma skin cancer in association with SKs may be greater than previously reported, particularly in SKs situated on photo damaged skin and of the reticulated type. SKs that have undergone recent growth or other clinical change should be biopsied and all SKs that are removed should be examined histologically.