[Effect of Signal Transduction Pathway Gene Mutations on the One- course Induced Remission Rate and Analysis of Clinical Characteristics in Patients with CBF-AML].

OBJECTIVE

To investigate the effect of other gene mutations outside the fusion gene on the first complete remission (CR) induced by one course of induction chemotherapy in patients with core binding factor-associated acute myeloid leukemia (CBF-AML).

METHODS

DNA was extracted from bone marrow or peripheral blood samples of newly diagnosed CBF-AML patients admitted to the Hematology Department of the Second Hospital of Shanxi Medical University from January 2015 to January 2019. Next-generation sequencing was used for detection of 34 kinds of hematologic malignancy-related gene mutations in patients with CBF-AML, the effect of related gene mutations on the first complete remission (CR) rate in one course of induction chemotherapy was analyzed by combineation with clinical characteristics.

RESULTS

34 kinds of genes in bone marrow or peripheral blood of 43 patients were detected by high throughput sequencing and the gene mutations were detected in 16 out of 34 genes. The mutation rate of KIT gene was the highest (48.8%), followed by NRAS (16.3%), ASXL1 (16.3%), TET2 (11.6%), CSF3R (9.3%), FLT3 (9.3%), KRAS (7.0%). The detection rates of mutations in different functional genes were as follows: genes related with signal transduction pathway (KIT, FLT3, CSF3R, KRAS, NRAS, JAK2, CALR, SH2B3, CBL) had the highest mutation frequency (72.1% (31/43); epigenetic modification gene mutation frequency was 30.2% (13/43), including ASXL1, TET2, BCOR); transcriptional regulation gene mutation frequency was 7.0% (3/43), including ETV6, RUNX1, GATA2). Splicing factor related gene mutation frequency was 2.3% (1/43), including ZRSR2). The CR rate was 74.4% after one course of induction chemotherapy. At first diagnosis, patients with low expression of WT1 (the median value of WT1 was 788.9) were more likely to get CR (P=0.032) and the RFS of patients who got CR after one course of induction chemotherapy was significantly longer than that of patients without CR [7.6 (2.2-44.1) versus 5.8 (1-19.4), (P=0.048)]. The rate of CR in the signal transduction pathway gene mutation group was significantly lower than that in non-mutation group (64.5% vs 100%) (P=0.045), while the level of serum hydroxybutyrate dehydrogenase (HBDH) was significantly higher than that in non-mutation group [(418 (154-2702) vs 246 (110-1068)] (P=0.032). There was no difference in CD56 expression between the two groups (P=0.053), which was limited to the difference between (≥20%) expression and non-expression. (P=0.048).

CONCLUSION

CBF-AML patients with signal transduction pathway gene mutation are often accompanied by high HBDH level and CD56 expression, moreover, the remission rate induced by one course of treatment is low.