Identification of cyclin D1 mRNA overexpression in B-cell neoplasias by real-time reverse transcription-PCR of microdissected paraffin sections.
OBJECTIVE
Overexpression of cyclin D1 mRNA and protein as a result of the chromosomal translocation t(11;14)(q13;q32) is a highly specific molecular marker of mantle cell lymphoma, but cyclin D1 dysregulation can also be found in other B-cell neoplasias. The aim of the study was to develop a precise and reliable tool for quantitation of cyclin D1 mRNA suitable for archival clinical specimens.


METHODS
A real-time reverse transcription-PCR (RT-PCR) assay was used to quantitate cyclin D1 mRNA copy numbers. Using 2000 microdissected cells as template, 104 formalin-fixed, paraffin-embedded lymph node, spleen, and decalcified bone marrow biopsies from a panel of 95 cases of B-cell non-Hodgkin's lymphomas (B-NHLs) were analyzed. In addition, cyclin D1 protein expression was assessed by immunohistochemistry.


RESULTS
Strong cyclin D1 mRNA overexpression was detected in mantle cell lymphomas (23 of 23), hairy cell leukemias (5 of 19), and multiple myelomas (7 of 23) with particularly high levels in 2 of the latter cases. Intermediate transcript levels were found in 5 of 23 multiple myelomas and 7 of 19 hairy cell leukemias. B-cell chronic lymphocytic leukemias (10 of 10), follicular lymphomas (9 of 9), mucosa-associated lymphoid tissue lymphomas (5 of 5) and reactive lymphoid tissues with the exception of normal spleen had no or very low cyclin D1 expression. In comparison with real-time RT-PCR, immunohistochemistry showed a lower level of sensitivity, more variability, and did not allow accurate quantitation.


CONCLUSIONS
Real-time RT-PCR for cyclin D1 mRNA is an excellent tool for the differential diagnosis of B-NHLs and, in combination with microdissection, a powerful approach for retrospective trials using archival clinical specimens as tissue source. Furthermore, real-time RT-PCR may help to identify subgroups of B-NHLs according to cyclin D1 mRNA copy numbers and to investigate the possible influence of different chromosomal breakpoints on cyclin D1 expression.
Specht
Katja
K
Institute of Pathology, GSF-National Research Centre for Environment and Health, D-85764 Neuherberg, Germany.
Kremer
Marcus
M
Müller
Ulrike
U
Dirnhofer
Stephan
S
Rosemann
Michael
M
Höfler
Heinz
H
Quintanilla-Martinez
Leticia
L
Fend
Falko
F
D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics; D003199:Computer Systems; D019938:Cyclin D1 / Q000096:biosynthesis / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015448:Leukemia, B-Cell / Q000145:classification / Q000235:genetics*; D007943:Leukemia, Hairy Cell / Q000235:genetics*; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics; D008221:Lymphoid Tissue / Q000378:metabolism; D016393:Lymphoma, B-Cell / Q000145:classification / Q000235:genetics*; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics; D008224:Lymphoma, Follicular / Q000235:genetics; D020522:Lymphoma, Mantle-Cell / Q000235:genetics; D009101:Multiple Myeloma / Q000235:genetics*; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics*; D016612:Paraffin Embedding; D019310:Pseudolymphoma / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis*; D012334:RNA, Neoplasm / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014178:Translocation, Genetic
D009363:Neoplasm Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D019938:Cyclin D1