Correlation between Bcl-2 Expression and the Efficacy of Bcl-2 Inhibitors in Patients with Myelodysplastic Syndromes

Background The heterogeneity of myelodysplastic syndromes (MDS) is strong, with poor efficacy of existing therapeutic regimens and large individual differences in patient prognosis. B-cell lymphomato-2 (Bcl-2) protein is highly expressed in patients with myeloid tumors, which has been proved by previous to be associated with disease progression, chemotherapy resistance, and shortened overall survival. The Bcl-2 inhibitor Veneckla (VEN) is approved for elderly patients with newly diagnosed acute myeloid leukemia (AML) who are not eligible for intensive therapy, and there is less data on its use in MDS patients. The difference in Bcl-2 expression in MDS patients and its correlation with the efficacy and prognosis of VEN therapy haven't been reported. Objective To analyse the expression of Bcl-2 protein in MDS patients and assess its correlation with the efficacy and prognosis of VEN treatment. Methods The clinical data of 71 patients with MDS admitted to Sichuan Academy of Medical Sciences·Sichuan Provincial People's Hospital from July 2018 to December 2022 were retrospectively analyzed. Baseline data of patients including gender, age, blood routine, blood biochemistry, bone marrow hemocytology, flow cytometry, chromosome karyotype, myeloid gene mutation, fusion gene mutation and MDS-EB typing were collected. The expression of Bcl-2 protein was detected by immunohistochemical staining. According to the modified International Prognostic Score System (IPSS-R), the patients were divided into 5 risk levels of very low risk (0 case), low risk (1 case), medium risk (7 cases), high risk (40 cases) and very high risk (23 cases). Patients with bone marrow Bcl-2 positivity≥10% were defined as Bcl-2 positive and0.05) . Conclusion Bcl-2 protein contributes to MDS fusion gene mutation and myeloid gene mutation; Bcl-2 positive expression was not associated with the survival of MDS patients. There was no difference in survival rate between Bcl-2 positive and Bcl-2 negative patients who received the VA combination regimen.