[Expression of bcl-2 gene in the evolution of chronic myelogenous leukemia to blast crisis and its implication].
OBJECTIVE
To investigate the expression of bcl-2 gene and cell apoptosis and cell cycle in bone marrow of chronic myelogenous leukemia (CML).


METHODS
APAAP assay and in situ hybridization were used for the expression of BCL-2 protein and bcl-2 mRNA in fresh bone marrow samples from 60 cases of CML. Flow cytometry was used to assess the extent of apoptosis and cell cycle percentage.


RESULTS
The expression of bcl-2 gene had no statistical difference between CMLs at presentation and in chronic phase, but was much lower in blast crisis (P < 0.05). The percentage of bcl-2 mRNA positive cells was consistent with BCL-2 protein expression. In addition, BCL-2 protein was related to the Hb levels, BPC, and immature cells in the peripheral blood and bone marrow. Notably, the extent of apoptosis in accelerated phase/blast crisis was much lower than that in chronic phase(P = 0.028), while the cell cycle had no difference.


CONCLUSIONS
High level of bcl-2 gene expression and low extent of apoptosis in bone marrow cells of CML might partially be the mechanism of poor prognosis of blast crisis, and this provides a new experimental basis for early diagnosis and treatment of CML blast crisis.
Sui
X
X
Institute of Hematology, State Key Laboratory of Experimental Hematology, CAMS and PUMC, Tianjin 300020.
Su
L
L
Chu
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000235:genetics*; D001752:Blast Crisis / Q000235:genetics*; D002648:Child; D005260:Female; D015870:Gene Expression; D019254:Genes, bcl-2; D006801:Humans; D015465:Leukemia, Myeloid, Accelerated Phase / Q000235:genetics / Q000473:pathology; D015466:Leukemia, Myeloid, Chronic-Phase / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger