[Relationship among telomerase activity, expression of human telomerase reverse transcriptase (hTERT), and expression of c-myc in acute leukemia].
OBJECTIVE
Regulation of expression of human telomerase reverse transcriptase(hTERT) is regarded as the major determinant of telomerase activity. Several studies suggested that c-myc could regulate hTERT expression. This study was designed to examine the telomerase activity, the expression of hTERT and c-myc, and to analyze their correlations in acute leukemia.


METHODS
The telomerase activity was semi-quantitatively assayed in mononuclear cells (MNCs) of bone marrow (BM) from 35 acute leukemia patients and 15 control cases by polymerase chain reaction enzyme- linked immunosorbent assay (PCR-ELISA). The mRNA expression of hTERT and c-myc were determined using reverse transcription polymerase chain reaction (RT-PCR) at the same time.


RESULTS
The mean telomerase activity, the expression levels of the hTERT mRNA and c-myc mRNA in acute leukemia were 0.71+/-0.32, 0.47+/-0.36, and 0.85+/-0.31, respectively, which was significantly higher than those of control cases (P< 0.01). The telomerase activity and the expression level of c-myc mRNA were associated with the expression level of hTERT mRNA (P< 0.01). In the 25 follow-up patients, the mean telomerase activity and the expression level of the hTERT were 0.61+/-0.39 and 0.29+/-0.31 in complete remission cases, while 0.83+/-0.23 and 0.53+/-0.31 in none complete remission cases, respectively. There was no significant difference between the two groups.


CONCLUSIONS
The telomerase activity and the expression of hTERT and c-myc mRNA were up-regulated in acute leukemia, and the elevated expression of hTERT may be an important adjuster of telomerase activity. It is likely that c-myc protein can stimulate the expression of hTERT and thereby enhance telomerase activity, which may involve in carcinogenesis of leukemia.
Cheng
Xu
X
First Affiliated Hospital of Suzhou University, Jiangsu Institute of Hematology, Suzhou, Jiangsu, PR China.
Chen
Zi-Xing
ZX
Wang
Wei
W
Fu
Jian-Xin
JX
Cen
Jian-Nong
JN
Yao
Li
L
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D004268:DNA-Binding Proteins; D005260:Female; D016259:Genes, myc; D006801:Humans; D007938:Leukemia / Q000188:drug therapy / Q000201:enzymology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D019098:Telomerase / Q000235:genetics* / Q000378:metabolism*
D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D019098:Telomerase