Proliferation profile of classical Hodgkin's lymphomas. Increased expression of the protein cyclin D2 in Hodgkin's and Reed-Sternberg cells.
There is accumulating evidence that Hodgkin's and Reed-Sternberg cells of classical Hodgkin's lymphomas (cHL) display multiple and concurrent alterations in different pathways and checkpoints of the cell cycle. However, the expression of cyclin D2 and its relation to other major cell cycle proteins has not been analyzed in cHL. The aim of the present study was to assess expression of cyclin D2, Ki67, cyclin A, cyclin B1, cyclin D1, cyclin D3, cyclin E, p53, Rb, p16 and p27 proteins in order to gain further insight into the proliferation profile of cHL. Overexpression of cyclin D2 in Hodgkin's and Reed-Sternberg cells was detected in 64/89 (72%) cases of cHL. This finding, in view of recent in vitro data showing that constitutive activation of nuclear factor (NF)-kB could upregulate cyclin D2 expression in part via signal transducer and activator of transcription (STAT)-5a, suggests that induction of cyclin D2 expression may support the proliferation of Hodgkin's and Reed-Sternberg cells. In addition, the present study showed that (1) increased p27 expression status was significantly correlated with higher levels of cyclin A expression (P=0.048) and (2) increased p53 expression status was significantly correlated with higher levels of cyclin A (P<0.001) and cyclin B1 (P=0.040) expression. The association between increased p27 and p53 expression status and higher expression levels of G2/M cyclins suggests that the impairment of the growth inhibitory activity of the p27 and p53 tumor suppressor pathways may promote the proliferation of Hodgkin's and Reed-Sternberg cells.
Bai
Maria
M
Department of Pathology, Medical Faculty, University of Ioannina, 45110 Ioannina, Greece. mbai@cc.uoi.gr
Tsanou
Elena
E
Agnantis
Niki John
NJ
Kamina
Sevasti
S
Grepi
Constantina
C
Stefanaki
Kalliopi
K
Rontogianni
Dimitra
D
Galani
Vassiliki
V
Kanavaros
Panagiotis
P
D002453:Cell Cycle / Q000502:physiology; D049109:Cell Proliferation; D019925:Cyclin A / Q000096:biosynthesis; D019926:Cyclin B / Q000096:biosynthesis; D056744:Cyclin B1; D056742:Cyclin D2; D016213:Cyclins / Q000096:biosynthesis*; D006689:Hodgkin Disease / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis; D016539:Reed-Sternberg Cells / Q000378:metabolism* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D015854:Up-Regulation
C534699:CCNB1 protein, human; C080336:CCND2 protein, human; D019925:Cyclin A; D019926:Cyclin B; D056744:Cyclin B1; D056742:Cyclin D2; D016213:Cyclins; D018809:Proliferating Cell Nuclear Antigen; D016159:Tumor Suppressor Protein p53; C413374:p27 antigen