Expression in non-Hodgkin's lymphoma of the bcl-2 protein associated with the t(14;18) chromosomal translocation.
For many non-Hodgkin's lymphomas, the bcl-2 gene has been implicated as a likely proto-oncogene, since it is consistently located at or near the breakpoint sites of t(14;18) chromosomal translocations. To define the role of the protein product of the bcl-2 gene in lymphoid cancers, we used anti-bcl-2 antibodies to perform immunohistochemical studies of frozen sections of 136 tissue specimens affected by lymphoma or non-neoplastic lymphoid disorders. Immunoreactive bcl-2 protein was observed in the neoplastic cells in almost all the follicular lymphomas, whereas no bcl-2 protein was detected in follicles affected by non-neoplastic processes or in normal lymphoid tissue. Every tumor with molecular-genetic evidence of t(14;18) translocation expressed detectable levels of bcl-2 protein, regardless of whether the breakpoint was located in or at a distance from the bcl-2 gene. These data show consistent expression of a proto-oncogenic protein in a large proportion of non-Hodgkin's lymphomas and provide further support of a role for bcl-2 in the pathogenesis of all lymphomas with the t(14;18) karyotypic abnormality. Increased expression of bcl-2 after t(14;18) translocations may be a specific marker for B-cell cancers, and demonstration of the protein with use of anti-bcl-2 antibodies could be useful in the diagnosis of many non-Hodgkin's lymphomas.
Ngan
B Y
BY
Department of Pathology, Stanford University School of Medicine, CA 94305.
Chen-Levy
Z
Z
Weiss
L M
LM
Warnke
R A
RA
Cleary
M L
ML
D001402:B-Lymphocytes; D002883:Chromosomes, Human, Pair 14; D002887:Chromosomes, Human, Pair 18; D006801:Humans; D007150:Immunohistochemistry; D008221:Lymphoid Tissue / Q000032:analysis; D008224:Lymphoma, Follicular / Q000032:analysis; D008228:Lymphoma, Non-Hodgkin / Q000032:analysis / Q000235:genetics* / Q000473:pathology; D000090063:Proto-Oncogene Mas; D011519:Proto-Oncogenes; D014178:Translocation, Genetic