HUMAN DNA QUANTIFICATION IN THE STOOLS OF PATIENTS WITH COLORECTAL CANCER

Background - Colorectal cancer is one of the main cause of cancer in the world. Colonoscopy is the best screen method, however the compliance is less than 50%. Quantification of human DNA (hDNA) in the feces may be a possible screen non-invasive method that is a consequence of the high proliferation and exfoliation of cancer cells. Objective - To quantify the human DNA in the stools of patients with colorectal cancer or polyps. Methods - Fifty patients with CRC, 26 polyps and 53 with normal colonoscopy were included. Total and human DNA were analyzed from the frozen stools. Results - An increased concentration of hDNA in the stools was observed in colorectal cancer patients compared to controls and polyps. Tumors localized in the left side of the colon had higher concentrations of hDNA. There were no difference between polyps and controls. A cut off of 0.87 ng/mL of human DNA was determined for colorectal cancer patients by the ROC curve, with a sensitivity of 66% and a specificity of 86.8%. For polyps the cut off was 0.41, the sensitivity was 41% and the specificity 77.4%. Conclusion - A higher concentration of hDNA had been found in colorectal cancer patients The quantification of hDNA from the stools can be a trial method for the diagnosis of colorectal cancer.

Contexto - O câncer colorretal é, mundialmente, uma das principais causas de câncer. A colonoscopia é o melhor método de rastreamento, no entanto a adesão é inferior a 50%. A quantificação de DNA humano (hDNA) nas fezes pode ser um possível método não invasivo de rastreamento, que é consequência da elevada proliferação e esfoliação de células cancerosas. Objetivo - Quantificar o DNA humano nas fezes de pacientes com câncer colorretal ou pólipos Métodos - Cinquenta pacientes com câncer colorretal, 26 pólipos e 53 com colonoscopia normal foram incluídas. DNA total e humano foram analisados a partir de fezes congeladas. Resultados - Maior concentração de hDNA nas fezes foi observada em pacientes com câncer colorretal em comparação com controles e pólipos. Pacientes com tumores localizados no cólon esquerdo apresentaram concentrações mais elevadas de hDNA. Não houve diferença entre pólipos e controles. Um nível de corte de 0.87ng/mL de DNA humano foi determinado para pacientes com câncer colorretal pela curva ROC, com sensibilidade de 66% e especificidade de 86,8%. Para pólipos o nível de corte foi de 0,41, a sensibilidade foi de 41% e a especificidade de 77,4%. Conclusão - Maior concentração de hDNA foi encontrada em pacientes com câncer colorretal. A quantificação de hDNA das fezes pode ser um método de rastreio do câncer colorretal.

Correlación de la t(9;22), t(12;21) e hiperdiploidía de ADN con el inmunofenotipo y la tasa de proliferación de células B neoplásicas en niños con leucemia linfoblástica aguda de precursores / Correlation of the t(9;22), t(12;21), and DNA hyperdiploid content with immunophenotype and proliferative rate of leukemic B-cells of pediatric patients with B-cell acute lymphoblastic leukemia

Introducción. Del 60 al 80 % de los pacientes con leucemia linfoblástica aguda de precursores B presentan alteraciones genéticas que influyen en el pronóstico de la enfermedad y en la biología del tumor. Objetivo. Analizar distintas alteraciones genéticas en leucemia linfoblástica aguda de precursores B en niños, y su relación con el inmunofenotipo y con la tasa de proliferación, en comparación con precursores B normales. Materiales y métodos. En 44 pacientes se evaluó, por citometría de flujo, el inmunofenotipo, el contenido de ADN y la proliferación, y por RT-PCR, las traslocaciones t(9;22), t(12;21), t(4;11) y t(1;19). Mediante un análisis jerarquizado de conglomerados se identificaron los patrones inmunofenotípicos de expresión asociados a las traslocaciones, tomando como referencia precursores B normales. Resultados. La cuantificación del ADN mostró que el 21 % de los casos de leucemia linfoblástica aguda de precursores B eran hiperdiploides de índice alto y, el 47,7 %, hiperdiploides de índice bajo. La presencia de hiperdiploidía se asoció con mayor proliferación tumoral y con inmunofenotipos aberrantes, que incluyeron expresión anormal de CD10, TdT, CD38 y CD45 y un mayor tamaño de los linfoblastos. La presencia de t(9;22) y t(12;21) discrimina células normales de células tumorales con aberraciones en la expresión de CD19, CD20, CD13, CD33, CD38, CD34 y CD45. Conclusiones. El perfil de aberraciones fenotípicas detectado en conjunto con anormalidades en la proliferación tumoral, se asocia de forma significativa con hiperdiploidiía de ADN y discrimina de forma clara linfoblastos con t(9;22) y t(12;21) de los precursores B normales. La identificación de estos parámetros será de gran utilidad como herramienta para la clasificación y seguimiento de los pacientes.

Introduction: Between 60 and 80% of patients with B-cell acute lymphoblastic leukemia show genetic abnormalities which influence the prognosis of the disease and the biology of the tumor. Objective: To analyze different genetic abnormalities in acute B lymphoblastic leukemia in children, its relationship with the immunophenotype and the proliferative rate compared with normal B cell precursors. Materials and methods: We assessed immunophenotype, DNA content and proliferative rate in 44 samples by flow cytometry, and translocations t(9;22), t(12;21), t(4;11), and t(1;19) by RT-PCR. Using a hierarchical cluster analysis, we identified some immunophenotypic patterns associated to genetic abnormalities when compared with normal B cell precursors. Results: DNA quantification showed that 21% of the cases had high hyperdiploidy and 47.7% has low hyperdiploidy. The presence of hyperdiploidy was associated with increased tumor proliferation and aberrant immunophenotypes, including abnormal expression of CD10, TdT, CD38, and CD45 and an increased size of the lymphoblasts. The presence of t(9;22) and t(12;21) discriminates normal cells from tumor cells with aberrant immunophenotype in the expression of CD19, CD22, CD13, CD33, CD38, CD34, and CD45. Conclusions: The aberrant immunophenotype profile detected in neoplastic cells along with abnormalities in the proliferative rate were significantly associated with DNA hyperdiploidy and clearly distinguished lymphoblasts with t(9;22) and t(12;21) from normal B cell precursors. The identification of these parameters is useful as a tool for classification and monitoring of these patients.

Micrometástasis: estrategias para su detección / Micrometastases: strategies for detection

La micrometástasis o enfermedad mínima residual ha adquirido una importancia trascendental en oncología al representar un verdadero problema clínico que debe ser solucionado, ya que aún se desconoce la respuesta de estos focos tumorales a los diferentes tratamientos que se usan para el control del cáncer. Aun cuando este es un problema específico fundamental a ser solucionado, ya existen métodos de ensayo inmunohistoquímicos y de biología molecular, que han permitido la ubicación de microfocos de células tumorales en diferentes órganos y tejidos, existiendo diferentes técnicas para determinar y cuantificar estas lesiones. Dentro de estas técnicas destacan la citometría de flujo y diferentes técnicas moleculares que van desde las ya tradicionales hasta las más nuevas y sofisticadas. El objetivo de la presente revisión está dirigido evaluar los nuevos métodos de diagnóstico que permitan la identificación de esta enfermedad residual, lo cual serviría para establecer tratamientos individualizados que pudieran prevenir la recurrencia de la enfermedad en los pacientes de cáncer bajo tratamiento.

Micrometastasis or minimal residual disease has become critically important in oncology since it represents a true clinical problem that must be solved, as the response of these tumor foci to the different treatments that are used for the control of cancer, is still unknown. Even though this is a fundamental specific problem to be solved, there are already immunohistochemical and molecular biology diagnostic methods that have allowed microfoci location of tumor cells in various organs and tissues, and different techniques are available to determine and quantify these lesions. Within these techniques, flow cytometry and different molecular methods are included, and they range from the traditional to the newest and most sophisticated. The goal of this review was aimed to evaluate new diagnostic methods that permit the identification of this residual disease, which would serve to establish individualized treatments and prevent the recurrence of the disease in cancer patients under treatment.

Identification of three new mutations in the RB1 gene in patients with sporadic retinoblastoma in Colombia / Identificación de tres nuevas mutaciones en el gen RB1 en pacientes con retinoblastoma esporádico en Colombia

Introduction. Retinoblastoma is a childhood cancer of the retina originated by altered or null retinoblastoma protein (pRb) expression. Genetic alterations in both RB1 alleles in the retinal cells are required for the development of retinoblastoma. In the sporadic form, non-hereditary RB1 gene mutations take place in a single retinoblast cell, and are therefore only present in tumor DNA (somatic mutations). Sporadic retinoblastoma is primarily unilateral, lacks family history and has no risk of transmission to descendants. Genetic tests for detection of RB1 mutation has improved the identification of carriers and facilitated accurate genetic counseling. Objective. To identify mutations in the RB1 gene in Colombian patients with sporadic retinoblastoma by PCR-SSCP followed by sequence. Materials and methods. Four patients with sporadic retinoblastoma were analyzed by PCR-SSCP, followed by DNA sequencing to identify variations in the RB1 gene. Results. We identified five variations in RB1 gene: three new mutations (one germline and two somatic mutations), one new polymorphism and one already reported somatic mutation. Four mutations were found in three patients with unilateral retinoblastoma and one mutation was found in a patient with bilateral retinoblastoma. One of these was a germline mutation in a sporadic unilateral retinoblastoma that was not present in the parents or three siblings analyzed. Conclusions. Our results emphasize the importance of identifying mutations for genetic counseling and clinical management of sporadic retinoblastoma patients. Description of a new RB1 gene variant is interesting since there have been a small number of polymorphisms reported for this gene.

Introducción. El retinoblastoma es un cáncer pediátrico de la retina originado por la expresión alterada o ausente de la proteína del retinoblastoma (pRb). Se requiere la alteración genética de ambos alelos RB1 en las células de la retina para el desarrollo del retinoblastoma. En la forma esporádica, las mutaciones no hereditarias del gen RB1 ocurren en un solo retinoblasto y están presentes sólo en el ADN del tumor (mutaciones somáticas). El retinoblastoma esporádico es generalmente unilateral, no tiene historia familiar y no tiene riesgo de transmisión a la descendencia. Las pruebas genéticas para la detección de mutaciones en RB1 han mejorado la identificación de portadores y han facilitado la precisión de la asesoría genética. Objetivo. Detectar mutaciones en el gen RB1 en pacientes colombianos con retinoblastoma esporádico mediante PCR-SSCP seguido de secuenciación. Materiales y métodos. Se analizaron cuatro pacientes con retinoblastoma esporádico para la detección de variaciones en el gen RB1 mediante PCR-SSCP, seguida de secuenciación. Resultados. Se identificaron cinco variaciones del gen RB1 : tres mutaciones nuevas (una de línea germinal y dos somáticas), un polimorfismo nuevo y una mutación somática ya reportada. Las cuatro mutaciones se encontraron en tres pacientes con retinoblastoma unilateral y uno con bilateral. La mutación germinal se detectó en un paciente con compromiso unilateral y no se encontró en los padres ni en los tres hermanos analizados. Conclusión. Estos resultados enfatizan la importancia, para asesoría genética y manejo clínico, de identificar mutaciones del gen RB1 en pacientes con retinoblastoma esporádico. La descripción de una nueva variante en RB1 es interesante, dado el muy bajo número de polimorfismos reportados para este gen.

Clonality analysis of giant cell lesions of the jaws

Despite the importance of clonality to understand the pathogenesis and progression of tumors, it has not been investigated yet in giant cell lesions of the jaws. The aim of this study was to analyze the clonality of peripheral giant cell lesions (PGCL) and central giant cell lesions (CGCL) of the jaws. Six samples of PGCL and 5 samples of CGCL were analyzed in this study using the polymorphic human androgen receptor locus (HUMARA) assay. Three out of the 5 samples of the CGCL and 3 out of 6 samples of PGCL exhibited a monoclonal pattern. Our findings demonstrate that some giant cell lesions of the jaws are clonal, which indicate that these lesions may have a common genetic mechanism of development. Further studies are necessary to better elucidate the molecular mechanisms involved in the pathogenesis of such lesions.

Apesar da importância que a clonalidade das lesões tem para o entendimento da patogênese e progressão dos tumores, ainda não foi feita essa investigação em lesões de células gigantes dos maxilares. O objetivo desse trabalho foi analisar a natureza clonal de lesões periféricas de células gigantes (LPCG) e de lesões centrais de células gigantes (LCCG). Foram analisadas nesse estudo 6 amostras de LPCG e 5 amostras de LCCG, sendo todas elas provenientes de pacientes do sexo feminino. Para essa investigação foi utilizado o método baseado na região polimórfica do exon um do gene humano para oreceptor de andrógeno (HUMARA). Três das 5 amostras de LCCG e 3 das 6 amostras de LPCG exibiram um padrão monoclonal. Nossos resultados demonstram que algumas lesões de células gigantes dos maxilares apresentam uma natureza monoclonal indicando que essas lesões podem ter um mecanismo genético comum de desenvolvimento. Outros estudos são necessários para uma maior compreensão dos mecanismos moleculares envolvidos na patogênese dessas lesões.

Optimization of methods to assess mitochondrial DNA in archival paraffin-embedded tissues from mammary canine tumors / Otimização dos métodos para avaliar o DNA mitocondrial obtido a partir de tumores mamários caninos incluídos em parafina

In this study we describe the alterations used to extract and amplify mitochondrial desoxyribonucleic acid (DNA) from formalin-fixed paraffin-embedded samples of canine mammary tumors. The epithelial and mesenchymal components (chondromyxoid and chondroid) of each tumor, as well as the normal mammary gland tissues, were manually microdissected from 19 mixed canine mammary tumors (10 benign mixed tumors and nine carcinomas arising in mixed tumors). DNA was extracted by Invisorb® Spin Tissue Mini Kit, with protocol changes proposed by the manufacturer. A 273-bp fragment was amplified by polymerase chain reaction (PCR) and submitted to automatic sequence analysis. The fragment was successfully analyzed in 100 percent of the samples. However, an additional lysis step, the reduction of volume in buffer solutions and PCR, a higher annealing temperature and an increase in the number of PCR cycles were required. The initial PCR products were diluted and re-amplified in six samples so that they could be successfully analyzed.

A presente comunicação descreve as modificações usadas para extrair e amplificar o DNA mitocondrial obtido de amostras de tumores mamários caninos fixados em formol tamponado a 10 por cento e incluídos em parafina. Os componentes epiteliais e mesenquimais (condromixóide e condróide), bem como a mama normal adjacente, foram microdissectados manualmente de 19 tumores mamários (10 tumores mistos benignos e nove carcinomas em tumores mistos). O DNA foi extraído utilizando-se o Invisorb® Spin Tissue Mini Kit com modificações do protocolo proposto pelo fabricante. Um fragmento de 273-pb foi amplificado por reação em cadeia da polimerase (PCR) e seqüenciado em seqüenciador automático. O fragmento foi analisado em 100 por cento das amostras, entretanto modificações como lise adicional, redução do volume das soluções de extração e PCR, aumento da temperatura de anelamento e do número de ciclos de amplificação foram necessárias. Em seis amostras os produtos iniciais de PCR foram diluídos e reamplificados para obtenção de sucesso.

p53 immunostaining is correlated with reduced survival and is not correlated with gene mutations in resected pulmonary large cell carcinomas

Malignancy of pulmonary large cell carcinomas (LCC) increases from classic LCC through LCC with neuroendocrine morphology (LCCNM) to large cell neuroendocrine carcinomas (LCNEC). However, the histological classification has sometimes proved to be difficult. Because the malignancy of LCC is highly dependent on proteins with functions in the cell cycle, DNA repair, and apoptosis, p53 has been targeted as a potentially useful biological marker. p53 mutations in lung cancers have been shown to result in expression and protein expression also occurs in the absence of mutations. To validate the importance of both p53 protein expression (by immunostaining) and p53 gene mutations in lung LCC (by PCR-single strand conformational polymorphism analysis of exons 5, 6, 7, and 8) and to study their relationships with clinical factors and sub-classification we investigated the correlation of p53 abnormalities in 15 patients with LCC (5 classic LCC, 5 LCNEC, and 5 LCCNM) who had undergone resection with curative intent. Of these patients, 5/15 expressed p53 and none had mutant p53 sequences. There was a negative survival correlation with positive p53 immunostaining (P = 0.05). After adjustment for stage, age, gender, chemotherapy, radiotherapy, and histological subtypes by multivariate analysis, p53 expression had an independent impact on survival. The present study indicates that p53 assessment may provide an objective marker for the prognosis of LCC irrespective of morphological variants and suggests that p53 expression is important for outcome prediction in patients with the early stages of LCC. The results reported here should be considered to be initial results because tumors from only 15 patients were studied: 5 each from LCC, LCNEC and LCCNM. This was due to the rarity of these specific diseases.

Fatores prognósticos no Mieloma Múltiplo / Prognostic factors in Multiple Myeloma

Nos últimos dez anos, grandes mudanças ocorreram no tratamento do MM com a utilização de novas drogas. Frente a estas novas opções de tratamento é essencial reconhecermos parâmetros clínicos ou biológicos que orientem a melhor escolha terapêutica. Mais recentemente foi validado um novo e simples sistema de estadiamento, International Staging System (ISS), baseado nos valores dabeta2 microglobulina e albumina sérica. Os pacientes são classificados em três grupos de risco: Estádio I: beta2M <3,5 mg/dl e albumina > 3,5 g/dl. Mediana de sobrevida de 62 meses; Estádio II: beta2 M <3,5 mg/l e albumina <3,5g/dl ou beta2 > 3,5 - < 5,5 mg/l. Mediana de sobrevida 49 meses; Estádio III: beta2 > 5,5 mg/l. Mediana de sobrevida de 29 meses. Atualmente, a citogenética e achados moleculares estão sendo amplamente reconhecidos como fatores de prognóstico. A deleção do cromossomo 13/13q-, translocação t(4;14), deleção p53 e, mais recentemente, a amplificação da banda cromossômica 1q21 estão associadas a prognóstico reservado.

Over the last 10 years, great changes have occurred in the treatment of multiple myeloma (MM) due to the use of new drugs. Considering the new options, it is essential to recognize clinical and biological parameters to arrive at the best therapeutic choice. More recently the new International Staging System (ISS) for multiple myeloma was validated which utilizes two straight forward laboratory parameters: the beta2 microglobulin (beta2M) and albumin levels. Stage I: beta2M < 3.5 mg/L and albumin level > 3.5 g/dL with a median survival of 62 months; stage II: beta2M < 3.5 and albumin < 3.5 g/dL or beta2M > 3.5 to < 5.5 g/dL with a median survival of 49 months; stage III: > 5.5 g/dL with a median survival of 29 months. The importance of cytogenetics and molecular features as prognostic factors is being recognized. Deletion of chromosome 13 or 13q, the t(4:14) translocation, p53 deletion and amplification of chromosome band 1q21 are all associated with poor prognosis.

Evaluation of DNA extraction methods and real time PCR optimization on formalin-fixed paraffin-embedded tissues.

Formalin-fixed, paraffin-embedded (FFPE) tissues are the most invaluable source of diagnostic material for studying pathogenesis of cancer and a variety of other diseases. Unfortunately, DNA extracted from formalin fixed tissues is highly degraded due to cross-linking between nucleic acid strands. Real Time PCR has become the standard for gene copy as well as RNA transcript determination. Thus, optimum standardization of Real Time PCR is crucial for obtaining accurate quantification for both research as well as for clinical diagnosis. However there are various factors which have negative impact . The aim of our study was to establish a simpler method of extraction and Real Time PCR Optimization for FFPE extracted DNA. Five breast cancer tissues that were formalin fixed and paraffin embedded were used for DNA extraction with four different methods. Extracted DNA was amplified with different primer sets that gave amplimers of different size. Optimization of Real Time PCR for EMSY, cyclin D1 and beta-globin genes was carried out on DNA obtained using heat treatment protocol for annealing temperature, primer concentration and template concentration. Highest quantity of DNA was obtained without the use of expensive reagents and in short time frame. PCR positivity was observed in case of shorter amplimer up to 250 bp in length. Amplimers of higher length failed to amplify with paraffin extracted DNA. Optimum annealing temperature for EMSY, Cyclin D1 and beta-globin genes were 60 degrees C, 60 degrees C and 61 degrees C respectively. Good results were seen with a primer concentration of 300 nM and 5 ng of template DNA. This study indicates that DNA obtained from formalin fixed paraffin embedded tissue is highly fragmented and can be used for successful amplification of shorter amplification products up to 250 bp in length. Optimization of real time PCR is important, especially while using SYBR green dye chemistry.

Evaluation of allelic alterations in 13 CODIS STR loci in tumor tissues from human digestive system / 法医学杂志

OBJECTIVE@#To study genetic alterations in 13 CODIS STR loci in various tumor tissue samples from human digestive system.@*METHODS@#Malignant tumor tissues and blood samples taken from 55 different unrelated individuals were collected. DNA samples were extracted using Chelex100 extraction kit, amplified using Profiler and Cofiler PCR amplification kit and analyzed using API 310 analyzer.@*RESULTS@#Aberrant cell divisions were detected in all of the 55 tumor tissue samples, with STR alternations detected in two samples including allelic alteration, partial and complete loss or unbalance of heterozygosity. Moreover, the alternations might occur simultaneously at more than one loci.@*CONCLUSION@#Caution must be taken in STR analysis of tumor tissue samples since the exclusion loci in forensic identification or paternity testing may be resulted from mutations in the tumor tissue.

Histopathological characteristics of a novel knock-in mouse prostate cancer model

Prostate cancer is relatively unique to man. There is no naturally occurring prostate cancer in the mouse. Pre-clinical studies involve the establishment of a genetically engineered mouse prostate cancer model with features close to those of the human situation. A new knock-in mouse adenocarcinoma prostate (KIMAP) model was established, which showed close-to-human kinetics of tumor development. In order to determine if the similar kinetics is associated with heterogeneous tumor architecture similar to the human situation, we utilized a new mouse histological grading system (Gleason analogous grading system) similar to the Gleason human grading system and flow cytometry DNA analysis to measure and compare the adenocarcinoma of the KIMAP model with human prostate cancer. Sixty KIMAP prostate cancer samples from 60 mice were measured and compared with human prostate cancer. Flow cytometry DNA analysis was performed on malignant prostate tissues obtained from KIMAP models. Mice with prostate cancer from KIMAP models showed a 53.3 percent compound histological score rate, which was close to the human clinical average (50 percent) and showed a significant correlation with age (P = 0.001). Flow cytometry analyses demonstrated that most KIMAP tumor tissues were diploid, analogous to the human situation. The similarities of the KIMAP mouse model with tumors of the human prostate suggest the use of this experimental model to complement studies of human prostate cancer.

Estudo da ploidia do DNA em adenomas colorretais / Study of DNA ploidy in colorectal adenomas

Objetivo: Analisar a ploidia do DNA em adenomas colorretais a fim de identificar a presença de aneuploidia como sendo um marcador de malignidade. Métodos: Trata-se de estudo transversal, prospectivo, realizado no Serviço de Endoscopia Digestiva do Hospital Geral da Universidade de Caxias do Sul, durante o período de junho de 2002 a 2004. Foram incluídos os pólipos adenomatosos de 22 pacientes submetidos a exames colonoscópicos. As variáveis estudadas foram: sexo, idade, tamanho do pólipo, tipo histopatológico e grau de displasia. Resultados: Alterações na ploidia do DNAforam vistas em 13 casos (59,09%). Todos os pacientes com displasia acentuada (n = 3) tinham estudo da ploidia de seu DNAanormal (p = 0,01). Em77,77% dos pólipos com displasia moderada (n = 7) verificou-se aneuploidia (p < 0,05). Emrelação ao diâmetro dos adenomas, verificou-se correlação positiva com a ocorrência de aneuploidia (p = 0,001). A comparação entre tipo histológico e aneuploidia não foi significativa.Conclusão: Adeterminação da aneuploidia tem sua utilidade como marcador biológico do potencial oncogênico dos adenomas colorretais. No presente estudo, em concordância com a literatura, a relação entre grau de displasia, diâmetro do adenoma e aneuploidia foi estatisticamente significativa.

Lack of association of VDR polymorphisms with Thai prostate cancer as compared with benign prostate hyperplasia and controls.

While still relatively low as compared to rates in the Western world, prostate cancer is on the increase in Asia, presumably due to change in dietary and other lifestyle factors. One risk factor is reported to be vitamin D (VD) and therefore the function of its receptor (VDR) could be of importance. In the present study polymorphims with functional significance in the Bsm, Apa 1 and Taq 1 genes were therefore compared in 28 prostate cancer (CaP), 44 benign prostate hyperplasia (BPH) and 30 control cases in Thailand. None demonstrated any significant variation in distribution within these three groups and therefore we conclude that vitamin D may not be major risk factor for prostate cancer in this population. However, there is considerable variation in the distribution frequencies from country to country and this, combined with differences in sun exposure, means that the results may not be extrapolated to the general case.

Teratoma facial / Facial teratoma

Ilustra un recién nacido del sexo masculino con presencia de una tumoración localizada en hemicara derecha de diez por nueve centímetros de tamaño y que ocupaba la región temporal, parotidea, geniana, maseterina, pre y retro auricular con desplazamiento del pabellón auricular hacia abajo y atrás.

Clinicopathological Significance of Maspin Expression in Breast Cancer

Maspin is a unique serine proteinase inhibitor that has tumor suppressor activity. It has been reported that maspin is expressed in normal human mammary epithelial cells and it is down-regulated during the progression of cancer. However, to date, there is very limited data on the clinical significance of maspin expression in human breast cancer. In this study, maspin expression was assessed immunohistochemically from 80 invasive ductal carcinoma (IDC) specimens of the breast. Also, maspin expression was compared with the clinicopathological factors (age, grade, tumor size and lymph node status), the expression of estrogen receptor (ER), progesterone receptor (PR) and p53, DNA ploidy and the overall survival in an attempt to assess its prognostic value. The maspin expression was positive in 25 IDC cases (31.3%). The maspin expression in IDC was significantly correlated with a higher histologic grade, a larger tumor size, a positive p53 status and shorter survival. There was an inverse association with maspin expression and the PR status. These findings suggest that maspin expression is not down-regulated with the progression of cancer and maspin expression may be associated with a poor prognosis. The immunohistochemical detection of maspin in breast cancers may be helpful for predicting an aggressive phenotype.

RET mutation status in medullary thyroid cancer(MTC) patients and the significance of genetic screening for mutations in their immediate relatives--a preliminary report.

Multiple Endocrine Neoplasia (MEN) 2A is an inherited disease characterized by the development of medullary thyroid carcinoma (MTC), pheochromocytoma(PHCH) and hyperparathyroidism(HPT). It has recently been shown to be associated with germline mutations in the RET proto-oncogene. Genetic testing for RET mutations will, therefore allow the identification of people with asymptomatic MEN 2 who can be offered prophylactic thyroidectomy and biochemical screening as preventive measures. No genetic study based on RET mutation detection has been available in India so far. The aim of the present study is to detect the proportion of MTC cases having inherited germline or somatic RET mutations and to identify family members at risk for MEN and, thereby the feasibility of screening for MEN. DNA extracted from the peripheral blood and somatic (tumor) tissues were subjected to PCR using primers for exons 10,11 and 16. A few samples were subjected to direct sequencing. Germline mutations were identified in 3 of 4 MEN 2A patients, 18 of 24 sporadic MTC(SMTC), 2 of 4 children of MEN2A and 8 relatives of SMTC. Common mutation was in exon 10 and 11 (c634). It is recommended that RET mutation analysis and counseling of patients and their immediate relatives be introduced on a regular basis to identify gene carriers.

Standard and quantitative analysis of cyclin E threshold by cyclin E/DNA multiparameter flow cytometry / 华中科技大学学报（医学）（英德文版）

The threshold of cyclin E expression at G1/S boundary is a characteristic feature of cell cycle progressing. In this study, we tried to develop a quantitative approach to analyze cyclin E threshold by multiparameter flow cytometry. The expression of cyclin E in exponentially growing MOLT-4 cells was detected under different photomultiplier tube (PMT) voltages by cyclin E/DNA multiparameter flow cytometry. Additionally, cyclin E was detected in cells which were treated with caffeine and cycloheximide (CHX) under the same PMT voltage. Moreover, the expression of cyclin E in MOLT-4 cells was compared with that in JURKAT cells. Cyclin E threshold was quantified by formula B2/AxC (A, B, C indicates the minimum, threshold, and maximum of cyclin E fluorescence intensity, respectively). Results showed that in MOLT-4 cells, cyclin E threshold calculated by formula B2/AxC was invariable under different PMT settings. It was decreased in cells treated with caffeine and remained changeless in cells treated with cycloheximide. Cyclin E threshold in JURKAT cells was much lower than that in MOLT-4 cells. It was suggested that Formula B2/AxC we firstly set up could be used to analyze cyclin E expression threshold quantitatively.

Lack of evidence for mutations or deletions in the CDKN2A/p16 and CDKN2B/p15 genes of Brazilian neuroblastoma patients

Neuroblastoma, the most common extracranial tumor in childhood, has a wide spectrum of clinical and biological features. The loss of heterozygosity within the 9p21 region has been reported as a prognostic factor. Two tumor suppressor genes located in this region, the CDKN2B/p15 and CDKN2A/p16 (cyclin-dependent kinase inhibitors 2B and 2A, respectively) genes, play a critical role in cell cycle progression and are considered to be targets for tumor inactivation. We analyzed CDKN2B/p15 and CDKN2A/p16 gene alterations in 11 patients, who ranged in age from 4 months to 13 years (male/female ratio was 1.2:1). The most frequent stage of the tumor was stage IV (50 percent), followed by stages II and III (20 percent) and stage I (10 percent). The samples were submitted to the multiplex PCR technique for homozygous deletion analysis and to single-strand conformation polymorphism and nucleotide sequencing for mutation analysis. All exons of both genes were analyzed, but no deletion was detected. One sample exhibited shift mobility specific for exon 2 in the CDKN2B/p15 gene, not confirmed by DNA sequencing. Homozygous deletions and mutations are not involved in the inactivation mechanism of the CDKN2B/p15 and CDKN2A/p16 genes in neuroblastoma; however, these two abnormalities do not exclude other inactivation pathways. Recent evidence has shown that the expression of these genes is altered in this disease. Therefore, other mechanisms of inactivation, such as methylation of promoter region and unproperly function of proteins, may be considered in order to estimate the real contribution of these genes to neuroblastoma genesis or disease progression.

Detection of DNA aneuploidy in exfoliated airway epithelia cells of sputum specimens by the automated image cytometry and its clinical value in the identification of lung cancer / 华中科技大学学报（医学）（英德文版）

To evaluate the value of detection of DNA aneuploidy in exfoliated airway epithelia cells of sputum specimens by the automated image cytometry for the identification of lung cancer, 100 patients were divided into patient group (50 patients with lung cancer) and control group (30 patients with tuberculosis and 20 healthy people). Sputum was obtained for the quantitative analysis of DNA content of exfoliated airway epithelial cells with the automated image cytometry, together with the examinations of brush cytology and conventional sputum cytology. Our results showed that DNA aneuploidy (DI>2.5 or 5c) was found in 20 out of 50 sputum samples of lung cancer, 1 out of 30 sputum samples from tuberculosis patients, and none of 20 sputum samples from healthy people. The positive rates of conventional sputum cytology and brush cytology were 16% and 32%, which was lower than that of DNA aneuploidy detection by the automated image cytometry (P0.05). Our study showed-that automated image cytometry, which uses DNA aneuploidy as a marker for tumor, can detect the malignant cells in sputum samples of lung cancer and it is a sensitive and specific method serving as a complement for the diagnosis of lung cancer.

Morphometric study of lymphoid cells in mycosis fungoides and its simulators.

The distinction of early stages of mycosis fungoides from benign lymphoid disorders of skin is difficult by conventional histological techniques. We studied 10 cases of mycosis fungoides, 10 cases of large plaque parapsoriasis, 10 cases of other benign lymphoid disorders of skin and 5 cases of lymph nodes. Nuclear area, perimeter of the nucleus, nuclear contour index, cytoplasmic area, form factor and nuclear cytoplasmic ratio as well as DNA-ploidy were determined by image analysis. There were statistically significant difference (P value < 0.05) between all parameters except nuclear cytoplasmic ratio of the lymphoid cells of Mycosis Fungoides and benign lymphoid disorders of skin. Aneuploidy was found in 50% cases of Mycosis Fungoides. Histopathological parameters like epidermotropism pautrier micro-abscess and atypical lymphocytic infiltrate in both epidermis and dermis were more marked in aneuploid than diploid cases. So, the determination of nuclear contour index and DNA-ploidy is of importance to differentiate between Mycosis Fungoides and benign lymphoid disorders of skin.