Neoplastic cells do not carry bcl2-JH rearrangements detected in a subset of primary cutaneous follicle center B-cell lymphomas.
ABSTRACT Whether primary cutaneous follicular lymphoma (PCFL) may or not represent a cutaneous equivalent to nodal follicular lymphoma (FL) is not determined. We have therefore investigated a series of PCFL to determine if tumoral cells carry or not the t(14;18)(q32;q21) translocation, a cytogenetic hallmark of nodal FL. Thirty cases of PFCL were selected according to the criteria of both the European Organisation for Research and Treatment of Cancer and the World Health Organization with 21 cases classified as grade 1 or 2 and 9 cases as grade 3. First, cutaneous tumors were studied by PCR for the amplification of bcl-2/JH rearrangements and by interphase fluorescence in situ hybridization using a dual color probe spanning t(14;18) breakpoints. Second, we tried to determine the origin of bcl2-JH-positive cells by a parallel bcl2-JH and immunoglobulin heavy chain gene amplification of blood mononuclear cells DNA and of DNA extracted from single microdissected B cells. Bcl2-JH rearrangements were amplified by PCR in skin of 9 of 30 (30%) patients with a similar-sized bcl2-JH rearrangement detected in the blood of 7 of these 9 cases. No t(14;18) breakpoint was detected by interphase fluorescence in situ hybridization analysis of 11 bcl2-JH-negative and 5 bcl2-JH-positive PCFL in contrast with its detection in the secondary cutaneous FL and in the nodal FL cases. Single-cell/multigene analysis showed that no single monoclonal B cells of PCFL carried the bcl2-JH rearrangement. Bystander or nontumoral t(14;18)+ B cells emigrating from blood may account for the detection of bcl2-JH rearrangements within PCFL material. Our study also underlines the diagnostic value of interphase fluorescence in situ hybridization to discriminate between t(14;18)-negative PCFL and extracutaneous FL involving the skin.
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ABSTRACT: Introdução: A proteína BCL2 encontrada na membrana mitocondrial interna, regula a apoptose inibindo a morte celular programada. A translocação (14;18), detectada em 70 a 85% dos linfomas foliculares, leva a superexpressão da proteína BCL2, pela justaposição do gene BCL2 ao segmento JH do gene da cadeia pesada da imunoglobulina. Porém, os achados da expressão da BCL2 em carcinoma de cabeça e pescoço são contraditórios. Objetivo: Investigar a presença da translocação (14;18) do gene BCL2 em carcinomas de cabeça e pescoço. Método: Foram examinadas 16 amostras de DNA, sendo 13 de carcinomas de células escamosas (CCE) e 3 de epidermoide (CE), por meio da reação em cadeia da polimerase (PCR). Resultados: O rearranjo BCL2/JH foi encontrado em 2 (15%) dos 13 casos de CCE e em nenhum dos 3 casos de CE. A média de frequência de moléculas com rearranjo foi de 46,44 x 107. Não foi observada associação entre a presença de rearranjo e a exposição ao tabaco e álcool (p=0,6545). Conclusão: Diferente dos resultados encontrados em linfomas foliculares a presença da translocação (14;18) em carcinomas de cabeça e pescoço não é comum e, quando ocorre, pode ser uma mutação ocasional não associada a exposição ao tabaco e álcool.01/2010; DOI:10.1590/S1809-48722010000300004
- Acta Oncologica 02/2008; 47(2):326-9. DOI:10.1080/02841860701558856 · 3.71 Impact Factor
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ABSTRACT: This paper introduces a sequential fast scheme of the Kalman type to solve the covariance equations of linear prediction. The new algorithm constitutes a generalization of the scheme introduced recently by D. Falconer and L. Ljung, and applies to a more general situation. The algo rithm is characterized by conceptual simplicity and efficiency. Although it is based on matrix partitioning concepts and shifting properties of the signal vector, it does not have the restriction of prewindowing as it is the case with the previously mentioned algorithm, thus it can be used to model small frames of signals as well as to model signals generated by an AR model, giving in this case the exact solution. Finally it must be noted that the algorithm is strictly time recursive and leads to O(13p) multiplications per recursion only. Thus, this new scheme is the fastest existing method for the sequential solution of the general covariance equations when prewindowing is not desirable.Acoustics, Speech, and Signal Processing, IEEE International Conference on ICASSP '82.; 06/1982