Combination of Venetoclax and Midostaurin Efficiently Suppressed Relapsed t(8;21)Acute Myeloid Leukemia With Mutant KIT After Failure of Venetoclax Plus Azacitidine Treatment

Mitochondria and Acute Leukemia: A Clinician's Perspective

Acute leukemia is a group of aggressive hematological malignancies, with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) being the most common types. The biology of acute leukemia involves complex genetic and epigenetic alterations that lead to uncontrolled cell proliferation and resistance to apoptosis. Mitochondrial dysfunction is a feature of acute leukemia that results in altered energy production, unregulated cell death pathways, and increased cancer cell survival. Apoptosis, particularly via the mitochondrial pathway, is crucial for cellular homeostasis and cancer prevention. In acute leukemia, disruption of apoptosis is pivotal in disease development and progression, with elevated levels of anti-apoptotic proteins conferring a survival advantage to leukemia cells and promoting resistance to conventional therapies. Targeting mitochondrial apoptosis using BH3 mimetics and anti-apoptotic protein inhibitors is a viable therapeutic strategy. Alterations in the mitochondrial membrane potential, metabolism, and dynamics also contribute to the pathogenesis of acute leukemia. Continued research is vital for developing novel therapies and enhancing survival outcomes in patients with acute leukemia while minimizing the long-term adverse effects of treatment. In this narrative review, we provide a birds-eye view of the available scientific literature on the importance of mitochondria in acute leukemia, and discuss the role of BH3 mimetics in targeting the mitochondrial internal apoptotic machinery.

Application of omics in the diagnosis, prognosis, and treatment of acute myeloid leukemia

Acute myeloid leukemia (AML) is the most frequent leukemia in adults with a high mortality rate. Current diagnostic criteria and selections of therapeutic strategies are generally based on gene mutations and cytogenetic abnormalities. Chemotherapy, targeted therapies, and hematopoietic stem cell transplantation (HSCT) are the major therapeutic strategies for AML. Two dilemmas in the clinical management of AML are related to its poor prognosis. One is the inaccurate risk stratification at diagnosis, leading to incorrect treatment selections. The other is the frequent resistance to chemotherapy and/or targeted therapies. Genomic features have been the focus of AML studies. However, the DNA-level aberrations do not always predict the expression levels of genes and proteins and the latter is more closely linked to disease phenotypes. With the development of high-throughput sequencing and mass spectrometry technologies, studying downstream effectors including RNA, proteins, and metabolites becomes possible. Transcriptomics can reveal gene expression and regulatory networks, proteomics can discover protein expression and signaling pathways intimately associated with the disease, and metabolomics can reflect precise changes in metabolites during disease progression. Moreover, omics profiling at the single-cell level enables studying cellular components and hierarchies of the AML microenvironment. The abundance of data from different omics layers enables the better risk stratification of AML by identifying prognosis-related biomarkers, and has the prospective application in identifying drug targets, therefore potentially discovering solutions to the two dilemmas. In this review, we summarize the existing AML studies using omics methods, both separately and combined, covering research fields of disease diagnosis, risk stratification, prognosis prediction, chemotherapy, as well as targeted therapy. Finally, we discuss the directions and challenges in the application of multi-omics in precision medicine of AML. Our review may inspire both omics researchers and clinical physicians to study AML from a different angle.

Pharmaco-phosphoproteomic analysis of cancer-associated KIT mutations D816V and V560G

The CD117 mast/stem cell growth factor receptor tyrosine kinase (KIT) is critical for haematopoiesis, melanogenesis and stem cell maintenance. KIT is commonly activated by mutation in cancers including acute myeloid leukaemia, melanoma and gastrointestinal stromal tumours (GISTs). The kinase and the juxtamembrane domains of KIT are mutation hotspots; with the kinase domain mutation D816V common in leukaemia and the juxtamembrane domain mutation V560G common in GISTs. Given the importance of mutant KIT signalling in cancer, we have conducted a proteomic and phosphoproteomic analysis of myeloid progenitor cells expressing D816V- and V560G-KIT mutants, using an FDCP1 isogenic cell line model. Proteomic analysis revealed increased abundance of proteases and growth signalling proteins in KIT-mutant cells compared to empty vector (EV) controls. Pathway analysis identified increased oxidative phosphorylation in D816V- and V560G-mutant KIT cells, which was targetable using the inhibitor IACS010759. Dysregulation of RNA metabolism and cytoskeleton/adhesion pathways was identified in both the proteome and phosphoproteome of KIT-mutant cells. Phosphoproteome analysis further revealed active kinases such as EGFR, ERK and PKC, which were targetable using pharmacological inhibitors. This study provides a pharmaco-phosphoproteomic profile of D816V- and V560G-mutant KIT cells, which reveals novel therapeutic strategies that may be applicable to a range of cancers.

Invasive fungal infection following venetoclax and posaconazole co-administration

The co-administration of venetoclax, a BCL-2 inhibitor, with a mould-active azole, such a posaconazole, has potential to both prevent invasive fungal infection (IFI) and reduce the required treatment dose, and cost, of venetoclax. Posaconazole drug-level monitoring is critical to ensuring adequate mould prophylaxis. A retrospective audit of 99 patients at a tertiary cancer centre, with myeloid malignancies co-prescribed venetoclax and posaconazole between January 2018 and April 2022, was undertaken to evaluate the adequacy of posaconazole prescribing and the rate of breakthrough IFI. Seventy-six patients (77%) had at least one posaconazole level measured in the study period, with 37% requiring a dose adjustment based on steady-state trough levels. Breakthrough IFI occurred in 4% of patients, typically within 1 month of commencing anti-mould prophylaxis. Close monitoring of posaconazole levels in venetoclax-treated patients, particularly in the early, outpatient setting, is critical.

Antiproliferative activity of a new derivative from the class of N-glycoside of indolo[2,3-a]pyrrolo[3,4-c]carbazoles

Introduction: The creation of highly effective original anticancer drugs remains an urgent direction of scientific research in tumor therapy. One of the promising groups in this regard is indolocarbazoles and their derivatives, which are capable of initiating various pathways of tumor cell death. The aim of the study was to evaluate an antiproliferative activity of a new, Russian derivative of N-glycoside substituted indolocarbazole 6-amino-12-(α-L-arabinopyranosyl)indolo[2,3-a]pyrrolo[3,4-c]carbazole-5,7-dione (LCS-1208) on models of transplantable tumors of mice and on human tumors in Balb/c nude mice.

Materials and methods: Indolocarbazole sensitivity to LCS-1208 was assessed on transplantable tumors of mice – lymphatic leukemia L-1210, cervical carcinoma (CC-5), and colon adenocarcinoma (CAC) by five-fold intraperitoneal administration (ip) of the LCS-1208 substance in single doses of 50, 75, 100 mg/kg. Investigation into the effectiveness of the LCS-1208 lyo dosage form was performed on subcutaneous xenografts of human colon cancer SW620 by an intravenous administration (iv). The antitumor effect was evaluated by the tumor growth inhibition (TGI) and an increase in life span (ILS) of the treated animals as compared with the control ones. Evaluation of specific antitumor activity on xenografts was performed according to the tumor/control (T/C%) criterion (maximum criterion T/C≤42%).

Results and discussion: According to the results of the study, the most sensitive to the action of the LCS-1208 substance in the case of an ip administration of a total dose of 375 mg/kg were CAC with TGI=97–62%, p≤0.001 up to 16 days after the treatment, and ILS=36% (criteria for TGI≥70% and ILS≥25%). On xenografts of a human colon cancer SW620, the effectiveness of the LCS-1208 lyo drug dosage form within the range of total doses from 50 to 150 mg/kg in case of iv to Balb/c nude mice was set at T/C = 35–2% (criterion T/C<42%).

Conclusion: The presented results suggest possible effectiveness of LCS-1208 in treatment of colon malignant tumors of humans.