Off-label hypomethylating agents and venetoclax (HMA/VEN) are often used for relapsed and refractory (R/R) AML patients. However, predictors of outcome are elusive. The objective of the current retrospective observational multicenter study of 240 adult patients (median age 68.6 years) with R/R AML was to establish a prognostic risk score. Overall response was documented in 106 (44%) patients. With a median follow-up of 31.5 months, 179 deaths were recorded. Median overall survival (mOS) was 7.9 months. In multivariate analysis of the subgroup with molecular information (n = 174), risk factors for inferior survival included the presence of extramedullary disease, HMA pretreatment and mutations in NF1, PTPN11, FLT3, and TP53, whereas mutated SF3B1 was identified as favorable risk factor. These risk factors were subsequently applied to construct an HR-weighted risk model that allocated patients to one of three risk groups with significantly different survival outcomes: favorable (n = 46; mOS 21.4 months), intermediate (n = 75; mOS 7.5 months), and adverse (n = 53; mOS 4.6 months; p < 0.001). The model was validated in 189 AML patients treated with HMA/VEN in first line. This clinical-molecular, 3-tiered venetoclax prognostic risk score (VEN-PRS) for HMA/VEN treatment outcomes in R/R AML patients will support the selection of appropriate treatment options in this high-risk population.

Pediatric high-grade gliomas of the subclass MYCN (HGG-MYCN) are highly aggressive tumors frequently carrying MYCN amplifications, TP53 mutations, or both alterations. Due to their rarity, such tumors have only recently been identified as a distinct entity, and biological as well as clinical characteristics have not been addressed specifically. To gain insights into tumorigenesis and molecular profiles of these tumors, and to ultimately suggest alternative treatment options, we generated a genetically engineered mouse model by breeding hGFAP-cre::Trp53^Fl/Fl::lsl-MYCN mice. All mice developed aggressive forebrain tumors early in their lifetime that mimic human HGG-MYCN regarding histology, DNA methylation, and gene expression. Single-cell RNA sequencing revealed a high intratumoral heterogeneity with neuronal and oligodendroglial lineage signatures. High-throughput drug screening using both mouse and human tumor cells finally indicated high efficacy of Doxorubicin, Irinotecan, and Etoposide as possible therapy options that children with HGG-MYCN might benefit from.

The prognosis of elderly AML patients is still poor due to chemotherapy resistance. The Hedgehog (HH) pathway is important for leukemic transformation because of aberrant activation of GLI transcription factors. MBZ is a well-tolerated anthelmintic that exhibits strong antitumor effects. Herein, we show that MBZ induced strong, dose-dependent anti-leukemic effects on AML cells, including the sensitization of AML cells to chemotherapy with cytarabine. MBZ strongly reduced intracellular protein levels of GLI1/GLI2 transcription factors. Consequently, MBZ reduced the GLI promoter activity as observed in luciferase-based reporter assays in AML cell lines. Further analysis revealed that MBZ mediates its anti-leukemic effects by promoting the proteasomal degradation of GLI transcription factors via inhibition of HSP70/90 chaperone activity. Extensive molecular dynamics simulations were performed on the MBZ-HSP90 complex, showing a stable binding interaction at the ATP binding site. Importantly, two patients with refractory AML were treated with MBZ in an off-label setting and MBZ effectively reduced the GLI signaling activity in a modified plasma inhibitory assay, resulting in a decrease in peripheral blood blast counts in one patient. Our data prove that MBZ is an effective GLI inhibitor that should be evaluated in combination to conventional chemotherapy in the clinical setting.

The majority of publications regarding SARS-CoV-2 infections in adult patients with acute leukemia (AL) refer to hematological patients in general and are not focused on acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL). We herein report a review of the current literature on adult AL patients infected with SARS-CoV-2. Overall, SARS-CoV-2-associated mortality ranges from 20–52% in patients with adult AL. AML patients have a particularly high COVID-19-related mortality. Of note, most of the available data relate to the pre-vaccination era and to variants before Omicron. The impact of COVID-19 infections on AL treatment is rarely reported. Based on the few studies available, treatment delay does not appear to be associated with an increased risk of relapse, whereas therapy discontinuation was associated with worse outcomes in AML patients. Therefore, the current recommendations suggest delaying systemic AL treatment in SARS-CoV-2-positive patients until SARS-CoV-2 negativity, if immediate AL treatment is not required. It is recommended to offer vaccination to all AL patients; the reported antibody responses are around 80–96%. Seronegative patients should additionally receive prophylactic administration of anti-SARS-CoV-2 monoclonal antibodies. Patients with AL infected with SARS-CoV-2 should be treated early with antiviral therapy to prevent disease progression and enable the rapid elimination of the virus.

The addition of gemtuzumab ozogamicin (GO) to intensive chemotherapy (IC) has become a mainstay in treating patients with core binding factor acute myeloid leukemia (CBF-AML). However, evidence for the efficacy of GO in this particular subgroup is primarily based on meta-analytic data from different trials conducted more than a decade ago. In this registry-based study, we evaluated the impact of adding GO to IC in 265 CBF-AML patients from the SAL, AMLCG, and CELL cooperative study groups. Patients receiving GO had a 2-year overall survival of 90% compared with 80% in those without GO (hazard ratio [HR] 0.45, 95% confidence interval [CI] 0.21–0.95, P = 0.036) and a 2-year event-free survival of 51% versus 36% (HR 0.69, 95% CI 0.48–0.99, P = 0.046). While complete remission rates in GO vs. non-GO patients were comparable (89% vs. 90%, P = 0.81), more GO patients achieved measurable residual disease-negative remission (77% vs. 49%, P < 0.001), resulting in numerically reduced cumulative incidence of relapse (HR 0.67, 95% CI 0.43–1.02, P = 0.06). Despite delayed platelet recovery, high-grade toxicities were not increased in GO-treated patients. These findings support the integration of GO into treatment protocols for IC-eligible patients with CBF-AML.