Expression of Bcl-2 protein in human primary breast carcinomas and its correlation with multifocality, histopathological types and prognosis.

The Bcl-2 gene product prevents programmed cell death (apoptosis) and possibly promotes tumour development. This protein has mainly been demonstrated in the cytoplasm of various normal and neoplastic cells, including normal mammary epithelia and breast carcinomas. The aim of this retrospective study was to correlate the immunohistochemical expression of Bcl-2 protein with the multi-unifocality and the histology of the two main types of breast carcinoma. We used monoclonal antibody 124 to investigate Bcl-2 expression in paraffin sections of 62 primary breast carcinomas. Bcl-2 expression was associated mainly with this lobular carcinoma. High Bcl-2 protein positivity was found in this type, and was statistically significant in comparison to the level of Bcl-2 in ductal, NOS carcinomas (lobular versus ductal, NOS, P < 0.0001). In the entire group, including all histological types, Bcl-2 expression was higher in multifocal tumours (P = 0.005). Statistical significance (P < 0.03) was also found within the group of ductal, NOS cases, showing that Bcl-2 protein expression is associated with multifocality, irrespective of the histology of breast carcinomas. No definite association between Bcl-2 expression and prognosis was found. Our results suggest that Bcl-2 protein plays some role in the development of multifocality in breast carcinomas.

Phenotype of Hodgkin and Sternberg-Reed cells and expression of CD57 (LEU7) antigen.

Possible associations between the immunophenotype of Hodgkin (H) and Sternberg-Reed (S-R) cells, the expression of CD57 (Leu 7) antigen, and the presence of Epstein-Barr virus (EBV) were investigated in lymph node specimens from 50 cases of Hodgkin's disease (HD), including 26 cases of mixed cellularity and 24 cases of nodular sclerosis. Tissues were fixed in 10% neutral formalin, or/and B5 solution. H and S-R cells were CD30+, CD15+ (85% of the cases) and LCA (CD45). A proportion of neoplastic cells positive for either T-cell markers (CD3) or B-cell markers (CD20) was observed in 10% and 34% of the cases, respectively. Membrane positivity for CD57 antigen was found in H and S-R cells in 10 cases (8 cases of mixed cellularity, and 2 cases of nodular sclerosis). Such immunopositivity was only observed in B5-fixed sections. No staining for CD57 antigen was identified in H and S-R cells of any case with CD20 positive neoplastic cells. H and S-R cells of both CD57-positive and CD57-negative cases were further studied by immunohistochemistry for LMP1, by in-situ hybridization for EBER and by polymerase chain reaction (PCR) for EBV-DNA. No association was identified between the expression of CD57 antigen and the presence of EBV sequences, transcripts or proteins. Our findings do not support a B-cell origin for H and S-R cells in CD57-positive cases of Hodgkin's disease and suggest that these neoplastic cells may be related to natural killer (NK) or T-cells expressing CD57 antigen.