Abstract：Objective: To analyze the expression transcript level and promoter hypermethylation of PDZ and LIM domain 4(PDLIM4) gene and the clinical correlations in Chinese patients with chronic myeloid leukemia(CML). Methods: Real-time quantitative PCR(RQ-PCR) and real-time quantitative methylation-specific PCR(RQMSP) assays were used to detect the expression and methylation status of PDLIM4 gene in the bone marrow samples from CML patients. Results: Down-regulated PDLIM4 expression was found in 8／36(22％) CML cases, with significant statistical difference compared with all 21 controls(Fisher′s Exact Test, P=0.021). There was a significant correlation between PDLIM4 expression and bcr／abl fusion transcript(r=0.434, P=0.043) in CML patients. Hypermethylation of PDLIM4 promoter was detected in 13／59(22％) CML patients, but not in all 24 controls(Fisher′s Exact Test, P=0.016). PDLIM4 hypermethylation was not correlated with blood parameters(P>0.05). The frequencies of PDLIM4 promoter hypermethylation increased during the disease progression, as it was 16％(7／44), 33％(2／6) and 44％(4／9) in chronic phase, accelerated phase and blast crisis, respectively. Conclusion: Hypermethylation of PDLIM4 promoter may be associated with the disease progression in CML.
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