The expression of Bcl-2 by proliferating cells varies in different categories of B-cell lymphoma.
OBJECTIVE
To investigate the relationship between Bcl-2 protein expression and cell proliferation at single-cell level in B-cell lymphomas using double-labelling techniques.


RESULTS
The relationship between Bcl-2 protein expression and cell proliferation was explored in 124 cases of B-cell lymphoma using double immunofluorescence labelling for Bcl-2 and Ki67. In follicular lymphoma, marginal zone lymphoma and a subset of chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL), neoplastic cells tended to lose Bcl-2 when they are in cell cycle. This pattern is usually maintained in both follicular lymphoma and CLL/SLL when they undergo high-grade transformation. In mantle cell lymphoma, diffuse large B-cell lymphoma and a subset of CLL/SLL, the inverse relationship (between Bcl-2 and Ki67) was not observed, i.e. the proliferating cells tended to show co-expression of Bcl-2.


CONCLUSIONS
In low-grade lymphomas, including those that are transformed, Bcl-2 expression is lost when cell proliferate. However, in more aggressive tumours (i.e. mantle cell and de novo diffuse large B-cell lymphomas) the inverse Bcl-2/Ki67 relationship was not observed. It would be of interest to explore the clinical implications in lymphoma of the presence and absence of the inverse Bcl-2/Ki67 pattern.
Masir
Noraidah
N
Pathology Department, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
Jones
Margaret
M
Lee
Abigail M
AM
Goff
Lindsey K
LK
Clear
Andrew J
AJ
Lister
Andrew
A
Marafioti
Teresa
T
Mason
David Y
DY
D014408:Biomarkers, Tumor / Q000378:metabolism*; D049109:Cell Proliferation; D006801:Humans; D007124:Immunoenzyme Techniques; D017404:In Situ Hybridization, Fluorescence; D019394:Ki-67 Antigen / Q000378:metabolism; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000378:metabolism / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000378:metabolism* / Q000473:pathology; D018442:Lymphoma, B-Cell, Marginal Zone / Q000378:metabolism / Q000473:pathology; D008224:Lymphoma, Follicular / Q000378:metabolism / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000378:metabolism / Q000473:pathology; D020522:Lymphoma, Mantle-Cell / Q000378:metabolism / Q000473:pathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2