Immunolocalization of PRAD1/cyclin D1 expression appears to be a useful diagnostic adjunct to discriminate mantle cell lymphoma from other non-Hodgkin's lymphomas.
Rearrangements at the bcl-1 MTC were detected in 13 (39%) of 33 cases of mantle cell lymphoma by PCR and in 13 (48%) of 27 cases by restriction analysis.
These lesions include c-myc translocation and p53 inactivation in small noncleaved-cell lymphoma, and bcl-2 and bcl-1 translocation in follicular (FL) and mantle-zone lymphoma, respectively.
Approximately 70% of centrocytic (mantle-cell) lymphomas have the chromosomal translocation t(11;14) (q13; q32) and associated rearrangements at the bcl-1 breakpoint locus and at the cyclin D1 (PRAD1, CCND1) gene, thus implicating this gene in the pathogenesis of centrocytic lymphoma.
We found oncogene rearrangements in five of the 14 cases: bcl-1 rearrangement on one mantle zone lymphoma, bcl-2 rearrangements in two follicular lymphomas, and c-myc rearrangements in two small noncleaved cell lymphomas.
Detection of the bcl-1 rearrangement at the major translocation cluster in frozen and paraffin-embedded tissues of mantle cell lymphomas by polymerase chain reaction.
Expression of retinoblastoma gene product (pRb) in mantle cell lymphomas. Correlation with cyclin D1 (PRAD1/CCND1) mRNA levels and proliferative activity.
Mantle cell lymphoma is a B cell lymphoproliferative disorder cytogenetically characterized by the t(11;14)(q13;q32) which at molecular level involves the Bcl-1/PRAD-1 gene.
Dysregulation of cyclin D1 by a t(11;14)(q13;q32) translocation occurs in most cases of mantle-cell lymphoma and in approximately 30% of multiple myeloma (MM) tumors in which a 14q32 translocation can be detected.
Mantle cell lymphoma is strongly associated with the t(11;14) chromosomal translocation that rearranges the bcl-1 oncogene (PRAD-1 gene) and immunoglobulin heavy chain gene.
We detected BCL-1 translocations in eight of eight patients with clinical and immunological features of mantle cell lymphoma, suggesting that the t(11;14) translocation is a critical event in the pathogenesis of MCL and may be a primary element for the diagnosis.