ABSTRACT
Over the last 2 decades, the introduction of targeted therapies and the advances in the detection of BCR::ABL1 oncogene have dramatically improved comprehensive care for patients with Chronic myeloid leukemia (CML). The once deadly malignancy has now transformed into a chronic disease with an overall patient survival approaching that of the age-matched general population. While excellent prognoses have been reported among CML patients in high-income countries, it is unfortunately not the same for those living in low and middle-income (LMIC) countries such as Tanzania. This disparity is largely contributed by barriers associated with the provision of comprehensive care including early diagnosis, access to treatment, and regular monitoring of the disease. In this review, we will share our experiences and lessons learned in setting up a network of comprehensive care for patients with CML in Tanzania.
Subject(s)
Fusion Proteins, bcr-abl , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Humans , Tanzania/epidemiology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy , Prognosis , Protein Kinase InhibitorsABSTRACT
BACKGROUND: BCR-ABL1-based resistance to imatinib, mainly resulting from BCR-ABL1 mutations, is largely solved after second- and third-generation tyrosine kinase inhibitors (TKIs) are discovered. Nonetheless, imatinib resistance without BCR-ABL1 mutations, including intrinsic resistance induced by stem cells within chronic myeloid leukemia (CML), remains the major clinical challenge for many patients. PURPOSE: To study the key active ingredients and corresponding target proteins in Huang-Lian-Jie-Du-Tang (HLJDT) against BCR-ABL1-independent CML resistance to therapeutics, and then explore its mechanism of against CML drug resistance. METHODS: Cytotoxicity of HLJDT and its active ingredients in BCR-ABL1-independent imatinib resistance cells was analyzed through MTT assay. The cloning ability was measured through soft agar assay. Monitoring therapeutic effect on Xenografted mice CML model by in vivo imaging technology and mice survival time. Predicting the potential target protein binding sites by the technology of photocrosslinking sensor chip, molecular space simulation docking, and use Surface Plasmon Resonance (SPR) technology . Flow cytometry to detect the ratio of stem progenitor cells (CD34+). Constructing bone marrow transplantation mice CML leukemia model, detect the effects on leukemia stem cells LSK (Lin-\ Sca-1+ \C-kit+) self-renewal. RESULTS: Treatment with HLJDT, berberine and baicalein inhibited cell viability and colony formation of BCR-ABL1-independent imatinib-resistant cells in vitro while prolonging survival in mouse with CML xenografts and transplatation CML-like mouse models in vivo. JAK2 and MCL1were identified as targets of berberine and baicalein. JAK2 and MCL1 are involved in multi-leukemia stem cell-related pathways. Moreover, the ratio of CD34+ cells in resistant CML cells is higher than in treatment-sensitive CML cells. Treatment with BBR or baicalein partially suppressed CML leukemic stem cells (LSCs) self-renewal in vitro and in vivo. CONCLUSION: From the above, we concluded that HLJDT and its key active ingredients (BBR and baicalein) allowed to overcome imatinib resistance with BCR-ABL1 independent by eradication of LSCs by targeting the JAK2 and MCL1 protein levels. Our results lay the foundation for applying HLJDT in patients with TKI-resistant CML.
Subject(s)
Berberine , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Leukemia, Myeloid, Acute , Humans , Mice , Animals , Imatinib Mesylate/pharmacology , Imatinib Mesylate/therapeutic use , Fusion Proteins, bcr-abl/genetics , Fusion Proteins, bcr-abl/metabolism , Myeloid Cell Leukemia Sequence 1 Protein , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Berberine/pharmacology , Drug Resistance, Neoplasm , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Leukemia, Myeloid, Acute/drug therapy , Stem CellsABSTRACT
Chronic myeloid leukemia (CML) is a well-characterized oncological disease in which virtually all patients possess a translocation (9;22) that generates the tyrosine kinase BCR::ABL1 protein. This translocation represents one of the milestones in molecular oncology in terms of both diagnostic and prognostic evaluations. The molecular detection of the BCR::ABL1 transcription is a required factor for CML diagnosis, and its molecular quantification is essential for assessing treatment options and clinical approaches. In the CML molecular context, point mutations on the ABL1 gene are also a challenge for clinical guidelines because several mutations are responsible for tyrosine kinase inhibitor resistance, indicating that a change may be necessary in the treatment protocol. So far, the European LeukemiaNet and the National Comprehensive Cancer Network (NCCN) have presented international guidelines on CML molecular approaches, especially those related to BCR::ABL1 expression. In this study, we show almost three years' worth of data regarding the clinical treatment of CML patients at the Erasto Gaertner Hospital, Curitiba, Brazil. These data primarily comprise 155 patients and 532 clinical samples. BCR::ABL1 quantification by a duplex-one-step RT-qPCR and ABL1 mutations detection were conducted. Furthermore, digital PCR for both BCR::ABL1 expression and ABL1 mutations were conducted in a sub-cohort. This manuscript describes and discusses the clinical importance and relevance of molecular biology testing in Brazilian CML patients, demonstrating its cost-effectiveness.
Subject(s)
Fusion Proteins, bcr-abl , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Humans , Brazil , Fusion Proteins, bcr-abl/genetics , Drug Resistance, Neoplasm/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Mutation , Protein Kinase Inhibitors/pharmacology , Translocation, GeneticABSTRACT
The interaction between small-molecule compounds of traditional Chinese medicine and their direct targets is the molecular initiation event, which is the key factor for toxicity efficacy. Psoralen, an active component of Fructus Psoraleae, is toxic to the liver and has various pharmacological properties. Although the mechanism of psoralen-induced hepatotoxicity has been studied, the direct target of psoralen remains unclear. Thus, the aim of this study was to discover direct targets of psoralen. To this end, we initially used proteomics based on drug affinity responsive target stability (DARTS) technology to identify the direct targets of psoralen. Next, we used surface plasmon resonance (SPR) analysis and verified the affinity effect of the 'component-target protein'. This method combines molecular docking technology to explore binding sites between small molecules and proteins. SPR and molecular docking confirmed that psoralen and tyrosine-protein kinase ABL1 could be stably combined. Based on the above experimental results, ABL1 is a potential direct target of psoralen-induced hepatotoxicity. Finally, the targets Nrf2 and mTOR, which are closely related to the hepatotoxicity caused by psoralen, were predicted by integrating proteomics and network pharmacology. The direct target ABL1 is located upstream of Nrf2 and mTOR, Nrf2 can influence the expression of mTOR by affecting the level of reactive oxygen species. Immunofluorescence experiments and western blot results showed that psoralen could affect ROS levels and downstream Nrf2 and mTOR protein changes, whereas the ABL1 inhibitor imatinib and ABL1 agonist DPH could enhance or inhibit this effect. In summary, we speculated that when psoralen causes hepatotoxicity, it acts on the direct target ABL1, resulting in a decrease in Nrf2 expression, an increase in ROS levels and a reduction in mTOR expression, which may cause cell death. We developed a new strategy for predicting and validating the direct targets of psoralen. This strategy identified the toxic target, ABL1, and the potential toxic mechanism of psoralen.
Subject(s)
Chemical and Drug Induced Liver Injury , NF-E2-Related Factor 2 , Chemical and Drug Induced Liver Injury/etiology , Ficusin/toxicity , Humans , Molecular Docking Simulation , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolism , TOR Serine-Threonine KinasesABSTRACT
This review reflects the presentations and discussion at the 14th post-American Society of Hematology (ASH) International Workshop on Chronic Myeloproliferative Malignancies, which took place on the December 10 and 11, 2019, immediately after the 61st ASH Annual Meeting in Orlando, Florida. Rather than present a resume of the proceedings, we address some of the topical translational science research and clinically relevant topics in detail. We consider how recent studies using single-cell genomics and other molecular methods reveal novel aspects of hematopoiesis which in turn raise the possibility of new therapeutic approaches for patients with myeloproliferative neoplasms (MPNs). We discuss how alternative therapies could benefit patients with chronic myeloid leukemia who develop BCR-ABL1 mutant subclones following ABL1-tyrosine kinase inhibitor therapy. In MPNs, we focus on efforts beyond JAK-STAT and the merits of integrating activin receptor ligand traps, interferon-α, and allografting in the current treatment algorithm for patients with myelofibrosis.
Subject(s)
Disease Susceptibility , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy , Myeloproliferative Disorders/etiology , Myeloproliferative Disorders/therapy , Anemia/diagnosis , Anemia/etiology , Anemia/therapy , Biomarkers , Biomarkers, Tumor , Combined Modality Therapy/adverse effects , Combined Modality Therapy/methods , Disease Management , Drug Development , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/complications , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Molecular Diagnostic Techniques , Molecular Targeted Therapy , Myeloproliferative Disorders/complications , Myeloproliferative Disorders/diagnosis , Prognosis , Single-Cell Analysis/methods , Translational Research, Biomedical , Treatment OutcomeABSTRACT
Chronic myeloid leukemia (CML) is the paradigm for targeted cancer therapy. RT-qPCR is the gold standard for monitoring response to tyrosine kinase-inhibitor (TKI) therapy based on the reduction of blood or bone marrow BCR-ABL1. Some patients with CML and very low or undetectable levels of BCR-ABL1 transcripts can stop TKI-therapy without CML recurrence. However, about 60 percent of patients discontinuing TKI-therapy have rapid leukaemia recurrence. This has increased the need for more sensitive and specific techniques to measure residual CML cells. The clinical challenge is to determine when it is safe to stop TKI-therapy. In this review we describe and critically evaluate the current state of CML clinical management, different technologies used to monitor measurable residual disease (MRD) focus on comparingRT-qPCR and new methods entering clinical practice. We discuss advantages and disadvantages of new methods.
ABSTRACT
Chronic myeloid leukemia (CML) results from the Philadelphia chromosome (Ph) translocation and expression of its fusion oncoprotein BCR-ABL1. BCR-ABL1 tyrosine kinase inhibitors (TKIs) are the standard therapy for Ph-positive CML. Achievement of deep molecular responses (typically defined as ≥4-log reduction in BCR-ABL1 RNA levels) is an emerging treatment goal becoming attainable for more patients due to the availability of second-generation TKIs. Deep molecular responses are associated with improved long-term outcomes and are required prior to attempting cessation of treatment in treatment-free remission clinical trials. The National Comprehensive Cancer Network and European LeukemiaNet recommend regular monitoring of BCR-ABL1 RNA levels using real-time quantitative polymerase chain reaction (RQ-PCR). However, BCR-ABL1 RQ-PCR is a complex laboratory-developed test; routine quantitative results from clinical diagnostic laboratories may differ from those used to establish the recommendations. Although an International Scale (IS) was developed for standardized reporting of BCR-ABL1 RNA levels, IS adoption has been slow in the United States, but is now used by the vast majority of laboratories. Here, we discuss the importance of molecular monitoring in CML, gaps between current and best molecular monitoring practices in the United States, and challenges and potential solutions for universal IS adoption in the United States.
Subject(s)
Fusion Proteins, bcr-abl/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Antineoplastic Agents/therapeutic use , Fusion Proteins, bcr-abl/antagonists & inhibitors , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Molecular Targeted Therapy , Prognosis , Protein Kinase Inhibitors/therapeutic use , Real-Time Polymerase Chain Reaction/methods , Real-Time Polymerase Chain Reaction/standards , Remission Induction , Treatment Outcome , United StatesABSTRACT
INTRODUCTION: Fusion of BCR-ABL1 genes causes chronic myeloid leukemia (CML). As a reliable marker of disease burden, it also serves as the target of tyrosine kinase inhibitors (TKIs). New more sensitive molecular diagnostic tools for BCR-ABL1 can contribute to therapeutic decision-making, especially in considering drug discontinuation for patients enjoying prolonged deep molecular response. Areas covered: Several novel platforms are transforming CML molecular diagnostics to enable faster point-of-care devices, better understanding of clonal diversity and resistance mutations. Here, we review these molecular platforms, knowing implementation in other hematological malignancies will ensue. Expert commentary: Treatment with TKI in CML is the first example of a highly effective targeted therapy. Monitoring of BCR-ABL1 mRNA is standard in assessing disease burden being highly predictive of outcomes recommended by both European LeukemiaNet (ELN) and National Comprehensive Cancer Network (NCCN); however, studies has demonstrated poor adherence to these recommendations. In both clinical practice and assay performance, further optimizing of BCR-ABL1 monitoring can be envisioned including point-of-care methods for increased availability of rapid, standardized testing and increasingly sensitive molecular assays that allow for quantification of MRD and detecting resistance mutations.