The impact of the BCR-ABL oncogene in the pathology and treatment of chronic myeloid leukemia

Advancing chronic myeloid leukemia research with next-generation sequencing: potential benefits, limitations, and future clinical integration

Next-generation sequencing (NGS) has emerged as a powerful tool for advancing research in chronic myeloid leukemia (CML) by providing a deeper understanding of its genetic complexity. Beyond detecting the hallmark BCR::ABL1 fusion gene, NGS has enabled the identification of additional mutations associated with disease progression, therapy resistance, and clonal evolution. NGS also facilitates the detection of rare BCR::ABL1 fusion variants and cryptic rearrangements, offering a more refined genetic characterization of the disease. Additionally, it enhances the study of minimal residual disease (MRD) and evolving resistance patterns, which are crucial for developing targeted therapeutic strategies. However, challenges such as data interpretation, standardization, and cost constraints continue to limit the widespread application of NGS in routine research and clinical settings. This review explores the contributions of NGS to CML research, highlighting its role in uncovering novel genetic alterations, tracking clonal evolution, and identifying potential therapeutic targets. As sequencing technologies evolve, NGS is expected to further shape the future of CML research, providing critical insights that may ultimately refine disease management strategies.

Structure and Dynamics of the ABL1 Tyrosine Kinase and Its Important Role in Chronic Myeloid Leukemia

Abelson (ABL1) tyrosine kinase is an essential component of non-receptor tyrosine kinases and is associated with numerous cellular processes, including differentiation and proliferation. The structural features of ABL1 include a distinct N-terminal cap region, a C-terminal tail, a bilobed kinase, SH2, and SH3 domains. These domains enable its engagement in several signaling cascades and dynamic control. The pathophysiology of chronic myeloid leukemia (CML) is mainly driven by the BCR-ABL1 oncoprotein, arising from dysregulation of ABL1 kinase, namely through its fusion to the breakpoint cluster region (BCR) gene. ABL1 is a crucial target in the treatment of CML as the BCR-ABL1 fusion causes uncontrolled cellular proliferation and resistance to apoptosis. Tyrosine kinase inhibitors (TKIs) targeting the ABL1 tyrosine kinase are playing a critical role in the treatment of CML through the inhibition of persistently activated signaling pathways mediated by the BCR-ABL1 fusion protein. The article examines the structural characteristics of ABL1, how they relate to CML, and the interactions between ABL1 and the current FDA-approved TKIs, emphasizing the kinase's critical function in carcinogenesis and its possible target status for tyrosine kinase inhibitors.

MDM2 inhibitors induce apoptosis by suppressing MDM2 and enhancing p53, Bax, Puma and Noxa expression levels in imatinib‑resistant chronic myeloid leukemia cells

Activation of BCR::ABL1 tyrosine kinase is the main pathogenic mechanism underlying chronic myeloid leukemia (CML) in 90% of affected patients. The prognosis for individuals with CML who receive treatment with BCR::ABL1 tyrosine kinase inhibitors (TKIs) such as imatinib, is promising, with a 5-year survival rate of >90%. However, unfortunately, 20-30% of patients who are treated with imatinib may become resistant to the BCR::ABL1 TKIs. The objective of the present study was to determine whether inhibitors of E3 ubiquitin-protein ligase Mdm2 (MDM2), a regulator of p53 that promotes apoptosis and is highly expressed in CML, could induce cell death in imatinib-resistant CML cells. Apoptosis and cell viability were evaluated using Annexin-V-positive cell count and caspase-3 activity, as well as trypan blue dye exclusion assay. Expression levels of MDM2, p53, Bax, Puma, Noxa, p21, and cleaved caspase-3 were determined via western blotting. MDM2 levels in both the cytoplasm and nucleus were found to be ~3-fold higher in K562/IR cells compared with K562 cells, while the levels of p53 in both cell structures were markedly lower. In addition, an examination of a publicly accessible database revealed that the levels of MDM2 were evidently greater in patients who did not respond to imatinib compared with those who did respond to the drug. NSC-66811 and Nutlin-3, MDM2 inhibitors, increased the percentage of Annexin-positive cells in K562/IR cells by 43 and 62% at concentrations of 10 and 25 µM, respectively. Furthermore, the MDM2 inhibitors increased the levels of Bax, Puma, Noxa, and p21 by increasing the expression of p53 and decreasing the expression of MDM2 in K562/IR cells. Additionally, pifithrin-α, a p53 inhibitor, suppressed MDM2 inhibitor-induced cell death in K562/IR cells. Overall, the findings of the present study highlight the therapeutic potential of MDM2 inhibitors for imatinib-resistant CML.

Ferroptosis as the new approach to cancer therapy

Cancer is characterized by unregulated cell proliferation, evasion of apoptosis, and a propensity for metastasis, making it a leading cause of morbidity and mortality globally. Major challenges in cancer treatment include drug resistance and tumor heterogeneity, which hinder the clinical efficacy of existing therapies. To enhance treatment outcomes, it is essential to integrate emerging biological insights and technological advancements with conventional therapeutic strategies. Recent research has identified various forms of cell death, which can be classified as either regulated or unregulated. Regulated cell death involves specific biochemical and signaling pathways, while unregulated cell death occurs passively and uncontrollably. Apoptosis, the most extensively studied form of regulated cell death, is primarily mediated by the activation of caspase proteases. Nevertheless, the resistance of many tumors to apoptotic pathways has shifted focus towards non-apoptotic forms of cell death, such as ferroptosis. Ferroptosis is an iron-dependent form of regulated necrosis characterized by extensive membrane damage resulting from lipid peroxidation. Numerous preclinical studies have demonstrated that inducing ferroptosis can significantly reduce tumor growth across a variety of cancer types. For instance, in a study involving breast cancer models, the use of ferroptosis inducers such as erastin and RSL3 led to a marked decrease in tumor volume and weight. This review aims to explore the potential of ferroptosis as a novel therapeutic strategy in cancer treatment.

Allostery in Disease: Anticancer Drugs, Pockets, and the Tumor Heterogeneity Challenge

Charting future innovations is challenging. Yet, allosteric and orthosteric anticancer drugs are undergoing a revolution and taxing unresolved dilemmas await. Among the imaginative innovations, here we discuss cereblon and thalidomide derivatives as a means of recruiting neosubstrates and their degradation, allosteric heterogeneous bifunctional drugs like PROTACs, drugging phosphatases, inducers of targeted posttranslational protein modifications, antibody-drug conjugates, exploiting membrane interactions to increase local concentration, stabilizing the folded state, and more. These couple with harnessing allosteric cryptic pockets whose discovery offers more options to modulate the affinity of orthosteric, active site inhibitors. Added to these are strategies to counter drug resistance through drug combinations co-targeting pathways to bypass signaling blockades. Here, we discuss on the molecular and cellular levels, such inspiring advances, provide examples of their applications, their mechanisms and rational. We start with an overview on difficult to target proteins and their properties-rarely, if ever-conceptualized before, discuss emerging innovative drugs, and proceed to the increasingly popular allosteric cryptic pockets-their advantages-and critically, issues to be aware of. We follow with drug resistance and in-depth discussion of tumor heterogeneity. Heterogeneity is a hallmark of highly aggressive cancers, the core of drug resistance unresolved challenge. We discuss potential ways to target heterogeneity by predicting it. The increase in experimental and clinical data, computed (cell-type specific) interactomes, capturing transient cryptic pockets, learned drug resistance, workings of regulatory mechanisms, heterogeneity, and resistance-based cell signaling drug combinations, assisted by AI-driven reasoning and recognition, couple with creative allosteric drug discovery, charting future innovations.

Atypical Femur Fracture in a Teenager on Chronic Imatinib Therapy

Atypical femoral fractures (AFFs) are rare fractures usually associated with medications that can ultimately alter bone metabolism. Imatinib, a drug prescribed for treatment of chronic myeloid leukemia (CML), has been associated with altered bone homeostasis, however, with unknown clinical significance. Here, we present the case of a 17-year-old female, with a diagnosis of CML undergoing chronic imatinib therapy, who developed an AFF treated successfully with prophylactic fixation with intramedullary nailing. Our case underscores the importance of prompt recognition of this entity to allow patients timely appropriate care, even at an early age.

Green synthesized Zingiber officinale-ZnO nanoparticles: anticancer efficacy against 3D breast cancer model

Aim: ZnO NPs were prepared via green synthesis utilizing Zingiber Officinale.Methodology: Physical characterization and biological activity were performed against 2D, and 3D spheroids MCF-7 cell lines.Results: The NPs exhibited 188.9, 175.7 and 171.2 nm size with charge of -8.2, -11.7 and -9.7 mV for the 2%, 3% and 4% formulations. XRD confirmed a wurtzite hexagonal phase. FTIR spectra showed Zn-O stretching vibrations. The 2%, 3% and 4% formulations presented IC50 values of 14.7, 26.2 and 47 μg/ml, respectively, with complete destruction of MCF-7 spheroids. Elevated TNF-α levels suggested an inflammatory-mediated mechanism of action.Conclusion: 2% Zingiber officinale-derived ZnO NPs showed antitumor potential against deserving further mechanistic and in vivo explorations.

Structure-Guided Drug Design Targeting Abl Kinase: How Structure and Regulation Can Assist in Designing New Drugs

The human protein Abelson kinase (Abl), a tyrosine kinase, plays a pivotal role in developing chronic myeloid leukemia (CML). Abl's involvement in various signaling pathways underscores its significance in regulating fundamental biological processes, including DNA damage responses, actin polymerization, and chromatin structural changes. The discovery of the Bcr-Abl oncoprotein, resulting from a chromosomal translocation in CML patients, revolutionized the understanding and treatment of the disease. The introduction of targeted therapies, starting with interferon-alpha and culminating in the development of tyrosine kinase inhibitors (TKIs) like imatinib, significantly improved patient outcomes. However, challenges such as drug resistance and side effects persist, indicating the necessity of research into novel therapeutic strategies. This review describes advancements in Abl kinase inhibitor development, emphasizing rational compound design from structural and regulatory information. Strategies, including bivalent inhibitors, PROTACs, and compounds targeting regulatory domains, promise to overcome resistance and minimize side effects. Additionally, leveraging the intricate structure and interactions of Bcr-Abl may provide insights into developing inhibitors for other kinases. Overall, this review highlights the importance of continued research into Abl kinase inhibition and its broader implications for therapeutic interventions targeting kinase-driven diseases. It provides valuable insights and strategies that may guide the development of next-generation therapies.

Advancements of metallic nanoparticles: A promising frontier in cancer treatment

The incidence of cancer is increasing and evolving as a major source of mortality. Nanotechnology has garnered considerable scientific interest in recent decades and can offer a promising solution to the challenges encountered with traditional chemotherapy. Nanoparticle utilization holds promise in combating cancer and other diseases, offering exciting prospects for drug delivery systems and medicinal applications. Metallic nanoparticles exhibit remarkable physical and chemical properties, such as their minute size, chemical composition, structure, and extensive surface area, rendering them versatile and cost-effective. Research has demonstrated their significant and beneficial impact on cancer treatment, characterized by enhanced targeting abilities, gene activity suppression, and improved drug delivery efficiency. By incorporating targeting ligands, functionalized metal nanoparticles ensure precise energy deposition within tumors, thereby augmenting treatment accuracy. Moreover, beyond their therapeutic efficacy, metal nanoparticles serve as valuable tools for cancer cell visualization, contributing to diagnostic techniques. Utilizing metal nanoparticles in therapeutic systems allows for simultaneous cancer diagnosis and treatment, while also facilitating controlled drug release, thus revolutionizing cancer care. This narrative review investigates the advancements of metal nanoparticles in cancer treatment, types and mechanisms in targeting cancer cells, application in clinical scenarios, and potential toxicity in medicine.

N6-methyladenosine (m6A) RNA modification in chronic myeloid leukemia: unveiling a novel therapeutic target

N6-methyladenosine (m6A), the most prevalent internal mRNA modification, plays a critical role in physiological processes by regulating gene expression through modulation of mRNA metabolism at multiple stages. In recent years, m6A has garnered significant attention for a deeper understanding of the initiation, progression, and drug resistance of various cancers, including hematological malignancies. Dysregulation of m6A has been implicated in both cancer promotion and suppression. m6A methylation is a complex regulatory process involving methyltransferases (writers), demethylases (erasers), and proteins that recognize specific m6A modifications (readers). This intricate interplay presents challenges for precisely modulating m6A levels, either globally or at specific sites. This review specifically focuses on the role of m6A in chronic myeloid leukemia (CML), a blood cancer characterized by the BCR-ABL1 fusion. We emphasize its impact on leukemia cell survival and drug resistance mechanisms. Notably, inhibitors targeting m6A regulators show promise in preclinical models, suggesting a potential therapeutic avenue for CML. Integrating our understanding of m6A biology with current treatment strategies may lead to more effective therapies, especially for patients with advanced-stage or resistant CML.

Historical Perspective and Current Trends in Anticancer Drug Development

Cancer is considered one of the leading causes of death in the 21st century. The intensive search for new anticancer drugs has been actively pursued by chemists and pharmacologists for decades, focusing either on the isolation of compounds with cytotoxic properties from plants or on screening thousands of synthetic molecules. Compounds that could potentially become candidates for new anticancer drugs must have the ability to inhibit proliferation and/or induce apoptosis in cancer cells without causing too much damage to normal cells. Some anticancer compounds were discovered by accident, others as a result of long-term research. In this review, we have presented a brief history of the development of the most important groups of anticancer drugs, pointing to the fact that they all have many side effects.

Multi-Omics Integration for Liver Cancer Using Regression Analysis

Genetic biomarkers have played a pivotal role in the classification, prognostication, and guidance of clinical cancer therapies. Large-scale and multi-dimensional analyses of entire cancer genomes, as exemplified by projects like The Cancer Genome Atlas (TCGA), have yielded an extensive repository of data that holds the potential to unveil the underlying biology of these malignancies. Mutations stand out as the principal catalysts of cellular transformation. Nonetheless, other global genomic processes, such as alterations in gene expression and chromosomal re-arrangements, also play crucial roles in conferring cellular immortality. The incorporation of multi-omics data specific to cancer has demonstrated the capacity to enhance our comprehension of the molecular mechanisms underpinning carcinogenesis. This report elucidates how the integration of comprehensive data on methylation, gene expression, and copy number variations can effectively facilitate the unsupervised clustering of cancer samples. We have identified regressors that can effectively classify tumor and normal samples with an optimal integration of RNA sequencing, DNA methylation, and copy number variation while also achieving significant p-values. Further, these regressors were trained using linear and logistic regression with k-means clustering. For comparison, we employed autoencoder- and stacking-based omics integration and computed silhouette scores to evaluate the clusters. The proof of concept is illustrated using liver cancer data. Our analysis serves to underscore the feasibility of unsupervised cancer classification by considering genetic markers beyond mutations, thereby emphasizing the clinical relevance of additional global cellular parameters that contribute to the transformative process in cells. This work is clinically relevant because changes in gene expression and genomic re-arrangements have been shown to be signatures of cellular transformation across cancers, as well as in liver cancers.