[Detecting methylation of the calcitonin gene in monitoring treatment and disease evolution for myelogenous leukemia].
OBJECTIVE
Calcitonin gene mostly appears hypomethylation in normal cells. Hypermethylation of calcitonin gene frequently implies malignancy transformation and is probably related to the progress of hematological malignancy tumors. However, studies on the significance of hypermethylation of calcitonin gene in the diagnosis and treatment of myelogenous leukemia were rarely reported. This study was designed to investigate the value of analyzing hypermethylation of the calcitonin gene for detecting minimal residual disease (MRD) and monitoring disease evolution in acute myeloid leukemia (AML) and chronic myeloid leukemia(CML).


METHODS
Digestion of DNA with Hpa II in combination with polymerase chain reaction (PCR) was used to examine the methylation patterns of the calcitonin gene in 31 cases with AML, 45 cases with CML (including 33 patients in chronic phase, 2 in accelerated phase, and 10 in blast crisis), and 14 healthy adults (used as control).


RESULTS
The hypermethylation of calcitonin gene was found in 25 of 31 cases with AML (80.6%), 0 of 14 healthy adults (0%) (P< 0.01). Follow-up study of 5 cases with AML showed that 4 cases who appeared hypermethylation of calcitonin gene at both diagnosis and complete remission relapsed 3, 5, 6, and 14 months respectively after complete remission; the other case without hypermethylation of calcitonin gene did not relapse 25 months after complete remission. Among 45 cases with CML, 3 of 33 in chronic phase, 2 of 2 in accelerated phase and 8 of 10 in blast crisis showed hypermethylation of calcitonin gene; there were significant differences between chronic phase group and blast crisis group (including accelerated phase) (P< 0.01); three cases with CML in chronic phase developed into blast crisis 10, 12, and 13 months after hypermethylation of calcitonin gene were detected.


CONCLUSIONS
Analyzing hypermethylation of calcitonin gene may be useful in assessing the prognosis of AML and monitoring disease evolution in CML.
Xie
Xian-He
XH
Department of Hematology, Affiliated Union Hospital, Fujian Medical University, Fuzhou, Fujian, PR China. xhxlyy@hotmail.com
Chen
Zhi-Zhe
ZZ
Zhang
Xue-Min
XM
Huang
Ming-Qing
MQ
D000293:Adolescent; D000328:Adult; D002116:Calcitonin / Q000235:genetics*; D019175:DNA Methylation; D005260:Female; D006801:Humans; D007951:Leukemia, Myeloid / Q000175:diagnosis / Q000235:genetics* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual
D002116:Calcitonin