WT1 Expression Levels Combined with Flow Cytometry Blast Counts for Risk Stratification of Acute Myeloid Leukemia and Myelodysplastic Syndromes

Immature forms of low density granulocytes are increased in acute myeloid leukemia and myelodysplastic syndromes

Neutrophils can promote or suppress tumor growth. These different immunological functions mirror a great heterogenicity of neutrophil maturation and activation status: low-density granulocytes (LDGs) and normal-density neutrophils (NDNs). LDGs participate in immune dysregulation during autoimmune disorders with an activated phenotype, while NDNs might exert immunosuppressive activities. Here, we investigated variations in distribution of LDGs and NDNs in benign and malignant hematological conditions using an optimized 10-color flow cytometry staining for immunophenotyping of the main circulating populations. A total of 102 consecutive subjects diagnosed with hematological malignancies was enrolled for immunophenotyping by flow cytometry. We showed impaired neutrophil subset distribution in myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) patients compared to healthy individuals, with intermediate and mature LDGs significantly reduced, also displaying a good diagnostic sensitivity in MDS (AUC, 0.793 and P = 0.0013; and AUC, 0.7319 and P = 0.0109, respectively) and AML (AUC, 0.9059 and P = 0.0069; and AUC, 0.9176 and P = 0.00057, respectively). In conclusion, LDG and NDN subsets could be altered in AML and MDS, in favor of more immature forms, suggesting that emergency hemopoiesis could be a first mechanism to sustain peripheral blood counts, while maintaining a pro-inflammatory microenvironment.

Prognostic impact of peripheral blood WT1 mRNA dynamics in patients with acute myeloid leukemia treated with venetoclax combination therapy

BACKGROUND

Wilms' tumor gene 1 (WT1) mRNA quantification is a useful marker of measurable residual disease in acute myeloid leukemia (AML). However, whether monitoring the WT1 mRNA levels may predict the outcome of venetoclax (VEN) combination therapy in AML is not reported. This study aims to elucidate whether WT1 mRNA dynamics could predict long-term prognosis.

METHODS

33 patients with untreated or relapsed/refractory AML evaluated for peripheral blood WT1 dynamics in VEN combination therapy were analyzed.

RESULTS

The median age was 73 years (range 39-87). Azacitidine was combined with VEN in 91% of patients. Overall, the median overall survival (OS) was 334 days (95% CI 210-482), and the complete remission (CR) plus CR with incomplete hematologic recovery rate was 59%. A 1-log reduction of WT1 mRNA values by the end of cycle 2 of treatment was associated with significantly better OS and event-free survival (EFS) (median OS 482 days vs. 237 days, p = 0.049; median EFS 270 days vs. 125 days, p = 0.02). The negativity of post-treatment WT1 mRNA value during the treatment was associated with significantly better OS and EFS (median OS 482 days vs. 256 days, p = 0.02; median EFS not reached vs. 150 days, p = 0.005). Multivariate analysis confirmed the significance of these two parameters as strong EFS predictors (HR 0.26, p = 0.024 and HR 0.15, p = 0.013, respectively). The increase in WT1 mRNA values was correlated with relapse.

CONCLUSION

This study demonstrates that WT1 mRNA dynamics can be a useful marker for assessing long-term prognosis of VEN combination therapy for AML.

Biomarkers of Response to Venetoclax Therapy in Acute Myeloid Leukemia

Recent progress in the use of massive sequencing technologies has greatly enhanced our understanding of acute myeloid leukemia (AML) pathology. This knowledge has in turn driven the development of targeted therapies, such as venetoclax, a BCL-2 inhibitor approved for use in combination with azacitidine, decitabine, or low-dose cytarabine for the treatment of newly diagnosed adult patients with AML who are not eligible for intensive chemotherapy. However, a significant number of AML patients still face the challenge of disease relapse. In this review, we will explore biomarkers that may predict disease progression in patients receiving venetoclax-based therapy, considering both clinical factors and genetic changes. Despite the many advances, we conclude that the identification of molecular profiles for AML patients who will respond optimally to venetoclax therapy remains an unmet clinical need.

Wilms' tumor gene 1 in hematological malignancies: friend or foe?

Wilms' tumor gene 1 (WT1) is a transcription and post-translational factor that has a crucial role in the biological and pathological processes of several human malignancies. For hematological malignancies, WT1 overexpression or mutation has been found in leukemia and myelodysplastic syndrome. About 70-90% of acute myeloid leukemia patients showed WT1 overexpression, and 6-15% of patients carried WT1 mutations. WT1 has been widely regarded as a marker for monitoring minimal residual disease in acute myeloid leukemia. Many researchers were interested in developing WT1 targeting therapy. In this review, we summarized biological and pathological functions, correlation with other genes and clinical features, prognosis value and targeting therapy of WT1 in hematological features.

Shift of N-MYC Oncogene Expression in AML Patients Carrying the FLT3-ITD Mutation

Mutations in the FLT3 gene not only lead to abnormalities in its structure and function, but also affect the expression of other genes involved in leukemogenesis. This study evaluated the expression of genes that are more characteristic of neuroblastoma but less studied in leukemia. N-MYC oncogene expression was found to be more than 3-fold higher in primary AML patients carrying the FLT3-ITD mutation compared to carriers of other mutations as well as patients with normal karyotype (p = 0.03946). In contrast to the expression of several genes (C-MYC, SPT16, AURKA, AURKB) directly correlated to the allelic load of FLT3-ITD, the expression of the N-MYC oncogene is extremely weakly related or independent of it (p = 0.0405). Monitoring of N-MYC expression in some patients with high FLT3-ITD allelic load receiving therapy showed that a decrease in FLT3-ITD allelic load is not always accompanied by a decrease in N-MYC expression. On the contrary, N-MYC expression may remain elevated during the first three months after therapy, which is additional evidence of the emergence of resistance to therapy and progression of AML.

Clinical efficacy of azacytidine and venetoclax and prognostic impact of Tim-3 and galectin-9 in acute myeloid leukemia and high-risk myelodysplastic syndromes: A single-center real-life experience

Treatment of acute myeloid leukemia (AML) and high-risk myelodysplastic syndromes (MDS) is difficult in older patients with comorbidities and high-risk disease factors. Venetoclax, the first-in-class Bcl-2 inhibitor, has proven efficacy and safety in combination with azacytidine for treatment of high-risk myeloid diseases. In this single-center real-life retrospective study, a total of 27 consecutive patients treated with azacytidine plus venetoclax were included, and clinical outcomes, hematological improvements, and biomarkers of responsiveness to therapy were compared to those observed in an historical cohort of 95 consecutive patients treated with azacytidine as single agent. Azacytidine plus venetoclax was effective and safe in older and frail AML and high-risk MDS patients, with median overall survival of 22.3 months, higher than that reported in phase III trial (14.7 months), and higher than that of historical cohort (5.94 months). Progression-free survival was higher in patients treated with the drug combination compared to those treated with azacytidine as single agent (p = 0.0065). Clinical benefits might increase when azacytidine and venetoclax are administered as upfront therapy (p = 0.0500). We showed that Tim-3 expression could be a promising therapeutic target in refractory/relapsed patients, and galectin-9 a biomarker of responsiveness to therapy. Moreover, patients treated with azacytidine and venetoclax displayed a higher overall survival regardless the presence of negative prognostic markers at diagnosis (e.g., increased WT1 copies and/or normalized blast count). These encouraging results in a real-world setting supported efficacy and safety of azacytidine plus venetoclax as upfront therapy in AML and high-risk MDS, with clinical outcomes comparable to those of clinical trials when an appropriate venetoclax management with bone marrow assessment at every first, second, fourth, and eighth cycle, and dose adjustments for toxicities are performed.