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Introduction: Clinical response and chemosensitivity of relapse or refractory AML patients were evaluated after rescue and bridge‐to‐transplant MEC (mitoxantrone, etoposide, and cytarabine) regimen. Methods and Patients: Fifty‐five consecutive AML patients were treated with MEC from 2009 to 2018. Chemosensitivity was evaluated by WT1 quantification. Results: 27/55 patients (49.1%) had AML resistant to induction and 28/55 patients (50.9%) had AML relapse. 25/55 patients (45.5%) achieved a CR after one course of MEC, and 12 patients (21.8%) achieved WT1 negativity. In 12 patients, a second MEC was administered. Four out of 12 patients improved significantly their response with the 2nd MEC. MEC was an effective bridge to transplant, 32/55 patients (58.2%) received an allogenic stem cell transplant. Median overall survival (OS) from MEC was 455 days (95% CI 307‐602 days.); patient with WT1 negative CR had the best OS (P<.000). Conclusion: WT1 is a useful marker of chemosensitivity after MEC as rescue and bridge‐to‐transplant therapy. [ABSTRACT FROM AUTHOR]

Background: Aneuploidy occurs in more than 20% of acute myeloid leukemia (AML) cases and correlates with an adverse prognosis.Methods: To understand the molecular bases of aneuploid acute myeloid leukemia (A-AML), this study examined the genomic profile in 42 A-AML cases and 35 euploid acute myeloid leukemia (E-AML) cases.Results: A-AML was characterized by increased genomic complexity based on exonic variants (an average of 26 somatic mutations per sample vs 15 for E-AML). The integration of exome, copy number, and gene expression data revealed alterations in genes involved in DNA repair (eg, SLX4IP, RINT1, HINT1, and ATR) and the cell cycle (eg, MCM2, MCM4, MCM5, MCM7, MCM8, MCM10, UBE2C, USP37, CK2, CK3, CK4, BUB1B, NUSAP1, and E2F) in A-AML, which was associated with a 3-gene signature defined by PLK1 and CDC20 upregulation and RAD50 downregulation and with structural or functional silencing of the p53 transcriptional program. Moreover, A-AML was enriched for alterations in the protein ubiquitination and degradation pathway (eg, increased levels of UHRF1 and UBE2C and decreased UBA3 expression), response to reactive oxygen species, energy metabolism, and biosynthetic processes, which may help in facing the unbalanced protein load. E-AML was associated with BCOR/BCORL1 mutations and HOX gene overexpression.Conclusions: These findings indicate that aneuploidy-related and leukemia-specific alterations cooperate to tolerate an abnormal chromosome number in AML, and they point to the mitotic and protein degradation machineries as potential therapeutic targets. [ABSTRACT FROM AUTHOR]

In acute myeloid leukemia (AML), the restoration of p53 activity through MDM2 inhibition proved efficacy in combinatorial therapies. WIP1, encoded from PPM1D, is a negative regulator of p53. We evaluated PPM1D expression and explored the therapeutic efficacy of WIP1 inhibitor (WIP1i) GSK2830371, in association with the MDM2 inhibitor Nutlin-3a (Nut-3a) in AML cell lines and primary samples. PPM1D transcript levels were higher in young patients compared with older ones and in core-binding-factor AML compared with other cytogenetic subgroups. In contrast, its expression was reduced in NPM1-mutated (mut, irrespective of FLT3-ITD status) or TP53-mut cases compared with wild-type (wt) ones. Either Nut-3a, and moderately WIP1i, as single agent decreased cell viability of TP53-wt cells (MV-4-11, MOLM-13, OCI-AML3) in a time/dosage-dependent manner, but not of TP53-mut cells (HEL, KASUMI-1, NOMO-1). The drug combination synergistically reduced viability and induced apoptosis in TP53-wt AML cell line and primary cells, but not in TP53-mut cells. Gene expression and immunoblotting analyses showed increased p53, MDM2 and p21 levels in treated TP53-wt cells and highlighted the enrichment of MYC, PI3K-AKT-mTOR and inflammation-related signatures upon WIP1i, Nut-3a and their combination, respectively, in the MV-4-11 TP53-wt model. This study demonstrated that WIP1 is a promising therapeutic target to enhance Nut-3a efficacy in TP53-wt AML. [ABSTRACT FROM AUTHOR]

Acute Myeloid Leukemia (AML) is an extremely heterogeneous group of hematological neoplasms, for which allogeneic stem cell transplantation (HSCT) still represents the only potentially curative option in the majority of cases. However, elderly age and clinically severe comorbidities may often exclude a wide amount of patients from this therapeutic approach, underlying the urgent need for alternative strategies. Thanks to the introduction of advanced high-throughput techniques, light is being shed on the pathogenesis of AML, identifying molecular recurrent mutations as responsible for the onset, as well as progression, of disease. As a consequence, and in parallel, many new compounds, including targeted therapies (FMS-like tyrosine kinase 3 (FLT3) and Isocitrate dehydrogenase 1-2 (IDH1-2) inhibitors), have found a wide room of application in this setting, and are now available in daily practice, or in late phases of clinical development. Moreover, several further innovative molecules are currently under investigation, and promising results for many of them have already been reported. In this review, we will present an update on the most relevant molecular alterations of AML, focusing on the most frequent genomic mutations of the disease, for which compounds have been approved or are still currently under investigation. [ABSTRACT FROM AUTHOR]