Expresión inmunohistoquímica de PCNA, Ki-67 y ciclina D1 en ameloblastomas multiquísticos / Immunohistochemical expression of PCNA, Ki-67 and cyclin D1 in solid ameloblastomas

Introducción: el ameloblastoma es un tumor odontogénico benigno, localmente agresivo, que debe su origen a partir de estructuras epiteliales involucradas en la odontogénesis. El objetivo del presente trabajo es identificar, por medio de técnicas inmunohistoquímicas, aspectos de los mecanismos regulatorios de proliferación celular y la relación de los diferentes subtipos histológicos con el comportamiento biológico de estos tumores. Materiales y métodos: se seleccionaron 10 ameloblastomas multiquísticos en los cuales se realizó inmunotinción con los marcadores PCNA, Ki-67 y Ciclina D1. La interpretación de las tinciones se basó en la intensidad, localización y los subtipos celulares. La valoración utilizada para contabilizar el número de células fue baja (menos del 10 por ciento), media (hasta el 50 por ciento) y alta (más del 50 por ciento). Resultados: la tinción fue positiva en 6 casos para PCNA, en 3 para Ki-67 y en 5 para ciclina D1, en las células basales periféricas, en los patrones foliculares y plexiformes, en las del esbozo del retículo estrellado y fue negativa en los patrones quísticos y acantomatosos. Conclusión: en base a los hallazgos se puede asumir que las células basales y parabasales de los patrones foliculares y plexiformes presentan mayor actividad proliferativa que otros patrones y determinarían la evolución y tratamiento

Expression of proliferating cell nuclear antigen [PCNA] related to the presence of human papillomavirus and epstein-barr virus infection in laryngeal carcinoma

Laryngeal carcinomas have a controversial association with multitude of carcinogenic agents that collaborate for cell transformation and complex pathogenesis. The objectives of the present study were to detect the frequency of HPV and EBV infection, and the expression of proliferating cell nuclear antigen [PCNA] in laryngeal carcinoma and to assess a possible association of each with the clinicopathologic data. The present study included 50 patients of laryngeal carcinoma admitted to the Otolaryngology Department, Alexandria University. The cases were assessed clinically and histopathologically. Unstained slides were used for immunohistochemical analysis for detection of HPV and EBV infection and PCNA. In addition, in situ hybridization technique was used for detection of HPV 16/18 infection. Among 50 studied cases, 82% were men and almost all were tobacco users. Although a male predominance, we found that male to female ratio in glottic tumors were higher than supraglottic tumors. Most cases were in clinical stage T3 [30%] and T4 [26%] at time of diagnosis. There was an association between lymph node metastasis and tumor grade. Glottic tumors are frequently grade I SCC whereas supraglottic tumors were mostly of higher grade [II and III] and tend to have more lymph node metastasis. EBV and HPV infection where detected immunohistochemically in 14% and 30% of laryngeal SCC cases. Using in situ hybridization analysis of HPV DNA type 16/18, 5 cases were found positive. EBV and HPV infection were found more frequent in glottic than supraglottic tumors. However there was no association between EBV and HPV infection with tumor grade and LN metastasis. Proliferative activity was significantly related to tumor differentiation, histologic grade and lymph node metastasis. There was a trend to EBV + and HPV-16/18 + SCC of the larynx to manifest a higher rate of PCNA expression. These results strengthen the hypothesis that mainly HPV infection and to a little extent EBV infection, have a role in the pathogenesis of a subset of laryngeal carcinomas

Immunohistochemical nuclear staining for P53, PCNA, and Ki-67 in different histologic varients of basal cell carcinoma

Structural alternation of P53 gene is a common genetic change associated with basal cell carcinoma [BCC]. Proliferation antigens are expressed in the nuclei of cell during specific stages of the cell cycle including proliferating cell nuclear antigen [PCNA] and Ki-67. Studies have suggested that PCNA and Ki-67 are useful diagnostic tools to differentiate benign from malignant neoplasm and useful prognostic markers in malignant neoplasms. The aim of this work is to detect the expression of P53, PCNA, and Ki-67 in different histologic variants of BCCs, to study the probability of using such markers as diagnostic and prognostic tools. Thirty patients with different histologic variants of BCCs were diagnosed histopathologically. Seven skin biopsies were taken as controls. Immnunohistochemical staining for P53, PCNA, and Ki-67 detection. There is variable degree of positivity of P53, PCNA, and Ki-67 with different histologic variants of BCCs. There is high significant relation between percentage of their positive cells and both aggressiveness and recurrence of BCCs. There is positive relation between P53 and PCNA expression. PCNA expression is greater than Ki-67 in all studied variants except for the superficial variants, which were negative for P53 expression. Both the tumor suppressor gene P53 and the proliferation markers; PCNA and Ki-67 are expressed in BCCs. They are reliable prognostic markers for aggressive behavior of BCCs. They are valuable tool in prediction of possible recurrence. Their staining appeared to be superior to traditional histologic features in predicting clinical recurrence in primary BCC's and further prospective studies in a larger patient group are warranted

Expressão dos fatores de proliferação celular PCNA e Ki-67 e receptores de estrogênio e progesterona em tecido mamário normal de mulheres na pós-menopausa submetidas a dois esquemas de terapia de reposição hormonal / Expression of cell proliferation factors PCNA and Ki-67 and estrogen and progesterone receptors in normal breast tissue of post-menopause women submitted to two types of hormonal replacement therapy

Foram colhidas amostras de tecido mamário de 32 mulheres saudáveis na pós-menopausa: 19 utilizaram esquema cíclico de estrogênio e pro-gestágeno (estrogênios conjugados 0,625mg, 21 dias por mês, associa-dos ao acetato de medroxiprogesterona, 5mg, nos últimos 12 dias) e 13 tomaram apenas estrogênios (estrogênios conjugados, 0,625mg, 21 dias por mês), todas durante 6 meses consecutivos. Foram realizadas biópsias mamárias antes e ao final dos 6 meses de tratamento. A análise imunohistoquímica foi feita com anticorpos anti-PCNA do tipo PC-10, anti-Ki-67 do tipo MIB-1, anti-receptor de estrogênio do tipo 1-D5 e anti-receptor de progesterona do tipo 1-A6. Não houve diferença significativa para os fatores de mediação (receptores) no grupo que utilizou o esquema cíclico (RE: P = 0,326; RP: P = 0,228). No grupo que utilizou apenas estrogênio, obteve-se um valor de P próximo ao limite de significância estatística para o RP (P = 0,053), mas não para o RE (P = 0,203). Com relação aos fatores de proliferação celular, não foi encontrada diferença estatisticamente significativa para o PCNA em ambos os grupos (esquema cíclico: P = 0,121; estrogênio isolado; P = 0,208). Houve tendência para elevação do Ki-67 no grupo que fez uso de estrogênio apenas (P = 0,084), o que não se observou no grupo que fez uso de esquema cíclico (P = 0,776). Estes resultados sugerem que a associação de progestágeno à terapia estrogênica nesse grupo de mulheres pós-menopausa, pode ter contribuído para uma possível redução na expressão do receptor de progesterona e a proliferação celular, estimada pelo marcador Ki-67, agindo como um fator moderador de proliferação celular. Novos estu-dos são necessários para comprovar esta hipótese.

Expressäo do antígeno nuclear de proliferaçäo celular (PCNA) e da proteína p53 em cistos odontogênicos / Study of the expression of the antígeno of celular proliferation (PCNA) and of the proteína p 53 in odontogênico cysts

Os cistos odontogênicos represetam entidades de interesse na clínica odontológica em funçäo de sua frequência e comportamento biológico variado. Levando em consideraçäo que a atividade proliferativa pode interferir no curso clínico dessas lesöes, foi avaliado nestetrabalho, a expressäo do PCNA e da proteína p53 em 11 ceratocistos odontogênico, 12 cistos dentígero, 12 cistos odontogênicos calcificantes e 11 cistos radiculares, através do método da streptavidina-biotina. Todos os casos analisados demonstraram positividade ao PCNA. Os ceratocistos odontogênicos e os cistos odontogênicos calcificantes expressaram maior reatividade com índices de 42,6 porcento e 41,13 porcento, respectivamente, enquanto cistos dentígeros e radiculares exibiram imunorreatividade em 32,45 porcento e 26,45 porcento, dos cistos estudados. Os índices de positividade do PCNA foram comparados entre os 4 grupos de cistos através da análise de variância e teste qui-quadrado, näo sendo verificada, no entanto, difernça estatisticamentesignificante. Por outro lado, somento 2 casos de cistos odontogênicos calcificantes e 1 cisto dentígero expressaram a proteína p53, os índices foram expressos em porcentuais. Frente a estes dados, concluímos que näo foi possível relacionar a expressäo da proteína p53 e do antígeno nuclear de proliferaçäo celular (PCNA) à atividade proliferativa do epitélio cístico e seu comportamento biológico (

Comparison of counter immunoelectrophoresis with immunoblotting for detection of anti-extractable nuclear antigen antibodies in systemic lupus erythematosus.

Anti-extractable nuclear antigen (ENA) antibodies were assayed by counter immunoelectrophoresis (CIE) and immunoblotting in patients with systemic lupus erythematosus (SLE). We found the two methods showed good concordance rates, the lowest being 67% for anti-SS-A. Immunoblotting was more sensitive in detecting anti-Sm, anti-SS-B and anti-PCNA (proliferating cell nuclear antigen); CIE was more sensitive for anti-nRNP and anti-SS-A. Overall, the prevalence of these anti-ENA antibodies in SLE was increased by 9-20% if immunoblotting was used in addition to CIE. Sera specific for the 52 kDa peptide of the SS-A antigen (anti-52kDa SS-A) were better detected by immunoblotting. Anti-PCNA antibody was found in 6.3% of SLE patients and was associated with active disease and hemolytic anemia. The positive rate of anti-Sm was 9% by CIE and 23.7% by immunoblotting and this antibody was a specific marker for SLE using either method. It was concluded that using immunoblotting in addition to CIE, the overall sensitivity of detection of anti-ENA antibodies in SLE was increased and clinically useful antibodies such as anti-52kDa SS-A and anti-PCNA could be detected.

Proliferating cell nuclear antigen immunostaining in breast carcinoma and its relationship to clinical and pathological variables.

Tumour proliferative activity of 74 breast lesions was assessed by determining mitotic index and immunostaining for proliferative cell nuclear antigen using Peroxidase antiperoxidase method. The indices were correlated with histomorphology and clinical stage of the disease. Positively stained nuclei and mitotic figures were counted per 1000 cells to calculate Proliferating Cell Nuclear Antigen (PCNA) and mitotic index respectively. Sixty four cases stained positive for PCNA. The index ranged between 0 to 98. PCNA index was significantly low in benign lesions as compared to malignant lesions (p < 0.0002). There was a linear correlation between the mitotic index and PCNA index. PCNA index also showed significant correlation with tumour size and histologic grade; however, it had no correlation with axillary lymph node status.