[mRNA and protein expression of apoptosis-regulating gene bcl-x in lymphomas].
OBJECTIVE
To observe mRNA and protein expression of bcl-x and explore the role of bcl-x in the regulation of apoptosis and oncogenesis and their value in differential diagnosis of lymphomas.


METHODS
Reverse transcription-polymerase chain reaction (RT-PCR) and citric acid-microwave-ABC immunohistochemistry (ICH) were used to observe mRNA transcription forms and protein distributions of bcl-x in 30 frozen tissues and 109 paraffin embedded tissues (both including reactive hyperplasia and common types of lymphoma).


RESULTS
RT-PCR revealed that all 30 frozen cases showed bcl-x transcription, of which 29 had bcl-x1 band and 13 had bcl-xs band. Bcl-x1 band was always stronger than bcl-xs band. IHC found that 97/109 cases had fine positive bcl-x granules in the cytoplasm. In lymphoid reactive hyperplasia, bcl-x exhibited weak immunoactivity in cells located in the germinal centers and interfollicular regions of the nodes but not in the mantle zone lymphocytes which surround germinal centers. In lymphomas, bcl-x immunoactivity was always strong and diffuse. The staining fractions in different types of lymphomas were significantly higher than those in lymphoid reactive hyperplasias (P > 0.05), but no significant difference was found between the positive rate and staining fraction of different types of lymphomas.


CONCLUSIONS
Bcl-x shows active mRNA transcription and high protein expression in lymphomas. The long isoform of bcl-x (bcl-xl) is the predominant expression. The characteristics of bcl-x protein expression may be helpful in differential diagnosis of reactive hyperplasia and lymphoma.
Zhou
X
X
Laboratory of Molecular Pathology, Cancer Hospital, Shanghai Medical University, Shanghai 200032.
Xu
L
L
He
K
K
Zhu
X
X
Zhu
W
W
Zhang
T
T
D017209:Apoptosis; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008223:Lymphoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051020:bcl-X Protein
C494811:BCL2L1 protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D051020:bcl-X Protein