[Quantitative Detection of CSF3R T618I Mutation in Acute Myeloid Leukemia and Chronic Neutrophilic Leukemia Based on TaqMan-MGB Probes].

OBJECTIVE

To develop a new TaqMan-MGB probe based quantitative real-time polymerase chain reaction (qPCR) assay for primary screening and follow-up monitoring of colony-stimulating factor 3 receptor (CSF3R ) T618I mutation in patients with acute myeloid leukemia (AML) and chronic neutrophilic leukemia (CNL).

METHODS

Specific primers and probes were designed using the Primer Express v3.0 software, and plasmid standards were constructed based on the wild-type (CSF3R wt) and mutant (CSF3R T618I) genomic DNA sequences. Standard curve was plotted for the quantitative detection of the hot spot mutation of CSF3R T618I. DNA samples were obtained from 421 AML and 12 CNL patients.

RESULTS

A novel qPCR system based on TaqMan-MGB probes for the quantitative detection of the CSF3R T618I mutation was successfully established. The predicted sensitivity level was at least 0.625% for CSF3R T618I mutant allele in a wild-type background. The detection rate of CSF3R T618I mutation in our cohort was 3.33% (14/421) in AML patients and 83.33% (10/12) in CNL patients, which was highly consistent with the results of high-depth target regional sequencing (TRS) and Sanger sequencing. No CSF3R T618I mutation was detected in 20 healthy donors. The mean variant allele frequency (VAF) of CSF3R T618I in mutation-positive CNL patients calculated using the standard curve was (38.90±15.20)%, which was significantly higher than that in mutation-positive AML patients ［(21.72±16.11)%, P =0.015］.

CONCLUSION

The innovative TaqMan-MGB probe-based qPCR methodology is a reliable, sensitive, and quantitative assay for the detection of CSF3R T618I mutation in patients with CNL and AML. This approach promises to facilitate the diagnosis of these diseases and enhance the monitoring of therapeutic response.