All 18 pretransformation follicular lymphoma specimens displayed at least one immunoglobulin gene and BCL-2 rearrangement in common with the corresponding histologically progressed lymphoma, indicating a clonal relationship between the original follicular lymphoma and the histologically transformed lymphoma.
The latter MYC rearranged follicular lymphoma was clinically aggressive and transformed to a high-grade lymphoma that led to the death of the patient within 20 months.
The bcl-2 gene, encoding a mitochondrial membrane protein suggested to play an important role in cell survival, is translocated into the Ig loci in about 80% of human follicular lymphomas, which results in a high level of expression.
Sequence analysis showed the amplified bcl-2/JH fragments to be unique to each individual sample and distinct from 24 sequenced follicular lymphoma-derived t(14;18) junctions, thus excluding contamination artifacts.
The pattern of Bcl-2 staining in follicular lymphoma is the inverse of the pattern in reactive hyperplasia, confirming a role for Bcl-2 immunolocalization in routine diagnosis.
The frequency of VH family use in FL was found to be similar to that reported for normal peripheral blood lymphocytes and is therefore also roughly proportional to VH family size.
The frequency of VH family use in FL was found to be similar to that reported for normal peripheral blood lymphocytes and is therefore also roughly proportional to VH family size.
Chromosomal translocations involving the heavy chain immunoglobulin locus on chromosome 14 and a region on chromosome 18 encoding the bcl-2 gene [t(14;18)] are a characteristic and prevalent chromosomal abnormality in nodal malignant lymphoma, particularly follicular lymphoma.
The bcl-3 pattern of expression also bears close resemblance to that of bcl-2 (Gurfinkel et al., 1987), which is frequently associated with human B follicular lymphomas [t(14; 18)] and some chronic lymphocytic leukemias (Adachi et al., 1989; 1990; Adachi & Tsujimoto, 1989).
The bcl-3 pattern of expression also bears close resemblance to that of bcl-2 (Gurfinkel et al., 1987), which is frequently associated with human B follicular lymphomas [t(14; 18)] and some chronic lymphocytic leukemias (Adachi et al., 1989; 1990; Adachi & Tsujimoto, 1989).
According to these characteristics, these tumours could be placed in between lymphocytic lymphomas (which usually express CD23) and follicular lymphomas (which commonly lack IgD and CD5 and bear CD10 as well as a t(14:18).
According to these characteristics, these tumours could be placed in between lymphocytic lymphomas (which usually express CD23) and follicular lymphomas (which commonly lack IgD and CD5 and bear CD10 as well as a t(14:18).
Most of human follicular lymphomas possess the t(14;18) chromosome translocation that juxtaposes the IgH gene to the 3' region of bcl-2 in a head-to-tail configuration.
Most of human follicular lymphomas possess the t(14;18) chromosome translocation that juxtaposes the IgH gene to the 3' region of bcl-2 in a head-to-tail configuration.