Refining AML Treatment: The Role of Genetics in Response and Resistance Evaluation to New Agents

CircRNAs as New Therapeutic Entities and Tools for Target Identification in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a genetically extremely heterogeneous disease. Drug resistance after induction therapy is a very frequent event resulting in poor medium survival times. Therefore, the identification of new targets and treatment modalities is a medical high priority issue. We addressed our attention to circular RNAs (circRNAs), which can act as oncogenes or tumor suppressors in AML. We searched the literature (PubMed) and identified eight up-regulated and two down-regulated circ-RNAs with activity in preclinical in vivo models. In addition, we identified twenty-two up-regulated and four down-regulated circRNAs with activity in preclinical in vitro systems, but pending in vivo activity. Up-regulated RNAs are potential targets for si- or shRNA-based approaches, and down-regulated circRNAs can be reconstituted by replacement therapy to achieve a therapeutic benefit in preclinical systems. The up-regulated targets can be tackled with small molecules, antibody-based entities, or other modes of intervention. For down-regulated targets, up-regulators must be identified. The ranking of the identified circRNAs with respect to therapy of AML will depend on further target validation experiments.

Deciphering the role of neddylation in tumor microenvironment modulation: common outcome of multiple signaling pathways

Neddylation is a post-translational modification process, similar to ubiquitination, that controls several biological processes. Notably, it is often aberrantly activated in neoplasms and plays a critical role in the intricate dynamics of the tumor microenvironment (TME). This regulatory influence of neddylation permeates extensively and profoundly within the TME, affecting the behavior of tumor cells, immune cells, angiogenesis, and the extracellular matrix. Usually, neddylation promotes tumor progression towards increased malignancy. In this review, we highlight the latest understanding of the intricate molecular mechanisms that target neddylation to modulate the TME by affecting various signaling pathways. There is emerging evidence that the targeted disruption of the neddylation modification process, specifically the inhibition of cullin-RING ligases (CRLs) functionality, presents a promising avenue for targeted therapy. MLN4924, a small-molecule inhibitor of the neddylation pathway, precisely targets the neural precursor cell-expressed developmentally downregulated protein 8 activating enzyme (NAE). In recent years, significant advancements have been made in the field of neddylation modification therapy, particularly the integration of MLN4924 with chemotherapy or targeted therapy. This combined approach has demonstrated notable success in the treatment of a variety of hematological and solid tumors. Here, we investigated the inhibitory effects of MLN4924 on neddylation and summarized the current therapeutic outcomes of MLN4924 against various tumors. In conclusion, this review provides a comprehensive, up-to-date, and thorough overview of neddylation modifications, and offers insight into the critical importance of this cellular process in tumorigenesis.

Personalizing precision medicine: Patients with AML perceptions about treatment decisions

BACKGROUND

This study aims to explore patients' with acute myeloid leukemia perceptions about precision medicine and their preferences for involvement in this new area of shared decision-making.

METHODS

Individual semi-structured interviews were conducted in Finland, Italy and Germany (n = 16). The study population included patients aged 24-79 years. Interviews were analyzed with thematic content analysis.

RESULTS

Patient's perceived lack of knowledge as a barrier for their involvement in decision-making. Treatment decisions were often made rapidly based on the patient's intuition and trust for the physician rather than on information, in situations that decrease the patient's decision capacity. The patients emphasized that they are in a desperate situation that makes them willing to accept treatment with low probabilities of being cured.

CONCLUSIONS

The study raised important issues regarding patients' understanding of precision medicine and challenges concerning how to involve patients in medical decision-making. Although technical advances were viewed positively, the role of the physician as an expert and person-of-trust cannot be replaced.

PRACTICE IMPLICATIONS

Regardless of patients' preferences for involvement in decision-making, information plays a crucial role for patients' perceived involvement in their care. The concepts related to precision medicine are complex and will imply challenges to patient education.

Distinct N7-methylguanosine profiles of circular RNAs in drug-resistant acute myeloid leukemia

Post-transcriptional methylation modifications, such as the N7-methylguanosine (m7G) modification, are increasingly acknowledged for their role in the development and resistance to chemotherapy in acute myeloid leukemia (AML). This study employed MeRIP-seq technology to investigate the m7G sites within circular RNAs (circRNAs) derived from human AML cells and drug-resistant AML cells, in order to identify these sites more comprehensively. In addition, a detailed analysis of the relationship between m7G and drug-resistant AML was conducted. The bioinformatics analysis was utilized to predict the functions of specific methylated transcripts. The findings revealed a significant difference in m7G level between AML cells and drug-resistant AML cells, suggesting a potentially critical role of m7G in circRNAs in drug-resistant AML development. The methylation of M7G could affect the circRNA-miRNA-mRNA co-expression during the development of AML resistance, which could further influence the regulation of resistance-associated target genes in AML. Furthermore, gene ontology analysis indicated that the distinct distribution pattern of circRNAs with m7G methylation in drug-resistant AML cells was correlated with metabolism-related pathways. These results suggested a potential association between drug-resistant AML and m7G methylation of circRNAs. Moreover, the results revealed a novel role of m7G RNA methylation in circRNAs in the progression of AML chemoresistance.

SLC25A1-associated prognostic signature predicts poor survival in acute myeloid leukemia patients

Background: Acute myeloid leukemia (AML) is a heterogeneous malignant disease. SLC25A1, the gene encoding mitochondrial carrier subfamily of solute carrier proteins, was reported to be overexpressed in certain solid tumors. However, its expression and value as prognostic marker has not been assessed in AML. Methods: We retrieved RNA profile and corresponding clinical data of AML patients from the Beat AML, TCGA, and TARGET databases (TARGET_AML). Patients in the TCGA cohort were well-grouped into two group based on SLC25A1 and differentially expressed genes were determined between the SLC25A1 high and low group. The expression of SLC25A1 was validated with clinical samples. The survival and apoptosis of two AML cell lines were analyzed with SLC25A1 inhibitor (CTPI-2) treatment. Cox and the least absolute shrinkage and selection operator (LASSO) regression analyses were applied to Beat AML database to identify SLC25A1-associated genes for the construction of a prognostic risk-scoring model. Survival analysis was performed by Kaplan-Meier and receiver operator characteristic curves. Results: Our analysis revealed that high expressed level of SLC25A1 in AML patients correlates with unfavorable prognosis. Moreover, SLC25A1 expression was positively associated with metabolism activity. We further demonstrated that the inhibition of SLC25A1 could inhibit the proliferation and increase the apoptosis of AML cells. In addition, a panel of SLC25A1-associated genes, was identified to construct a prognostic risk-scoring model. This SLC25A1-associated prognostic signature (SPS) is an independent risk factor with high area under curve (AUC) values of receiver operating characteristic (ROC) curves. A high SPS in leukemia patients is associated with poor survival. A Prognostic nomogram including the SPS and other clinical parameters, was constructed and its predictive efficiency was confirmed. Conclusion: We have successfully established a SPS prognostic model that predict outcome and risk stratification in AML. This risk model can be used as an independent biomarker to assess prognosis of AML.

Targeting Apoptosis in AML: Where Do We Stand?

Simple Summary

In patients with acute myeloid leukemia (AML), genetic mutations can cause cells to evade regulated cell death (RCD), resulting in excessive cell proliferation. The best-known form of RCD is apoptosis, which prevents the emergence of cancer cells; disturbances in this process are an important factor in the development and progression of AML. Clearly, it is essential to understand the mechanisms of apoptosis to establish a personalized, patient-specific approach in AML therapy. Therefore, this paper comprehensively reviews the current range of AML treatment approaches related to apoptosis and highlights other promising concepts such as neddylation.

Abstract

More than 97% of patients with acute myeloid leukemia (AML) demonstrate genetic mutations leading to excessive proliferation combined with the evasion of regulated cell death (RCD). The most prominent and well-defined form of RCD is apoptosis, which serves as a defense mechanism against the emergence of cancer cells. Apoptosis is regulated in part by the BCL-2 family of pro- and anti-apoptotic proteins, whose balance can significantly determine cell survival. Apoptosis evasion plays a key role in tumorigenesis and drug resistance, and thus in the development and progression of AML. Research on the structural and biochemical aspects of apoptosis proteins and their regulators offers promise for new classes of targeted therapies and strategies for therapeutic intervention. This review provides a comprehensive overview of current AML treatment options related to the mechanism of apoptosis, particularly its mitochondrial pathway, and other promising concepts such as neddylation. It pays particular attention to clinically-relevant aspects of current and future AML treatment approaches, highlighting the molecular basis of individual therapies.