[Analysis of SRSF2 Gene Mutation in Patients with Chronic Myelomonocytic Leukemia].

Objective: To characterize the occurrence of SRSF2 mutations in chronic myelomonocytic leukemia(CMML) patients and their correlation with other gene mutations and some clinical characteristics.

Methods: The clinical data of 43 CMML patients diagnosed in Changzhou No.2 People's Hospital and Wuxi No.2 People's Hospital were retrospectively analyzed, and gene mutations detection was performed using next-generation sequencing (NGS).

Results: Among the 43 CMML patients the SRSF2 mutation detection rate was 39.5%(17/43). These mutations clustered collectively at the proline 95 residue in the splicing factor SRSF2. The other genes with mutation rate greater than 15% were ASXL1 (48.8%), TET2 (41.9%), NRAS (30.2%), RUNX1 (25.6%), and SETBP1 (16.3%). Among SRSF2- mutated patients, the most common co-mutation was ASXL1, followed by TET2. The median age of SRSF2 mutant patients was significantly higher than that of the wild type (68 vs 51.5, P < 0.001), but there was not statistically significant differences in gender, peripheral leukocytes, hemoglobin, platelets, karyotype, and blast cell compared to the wild-type (all P >0.05). Notably, 4 out of the 6 SRSF2 ^mutASXL1^mut CMML patients developed leukemia transformation, and 1 out of 10 SRSF2 ^wtASXL1^wt CMML patients developed leukemia transformation, with statistically significant difference in leukemia transformation rates (66.7% vs 10%, P =0.036).

Conclusion: SRSF2 mutations have a high incidence in CMML, occurring frequently in older patients, and often coexisting with ASXL1 and TET2 mutations. Patients with CMML carrying both SRSF2^mut ASXL1^mut double mutations have a higher risk of acute leukemia transformation.