The Philadelphia chromosome in leukemogenesis. Chin J Cancer. 2016;35:48. [PMID: 27233483 PMCID: PMC4896164 DOI: 10.1186/s40880-016-0108-0]

A prognostic approach on a case of pediatric Philadelphia chromosome-positive acute lymphoblastic leukemia with monosomy-7

In this work, we present the first case of a Ph-positive ALL Moroccan girl with t(9;22)(q34;q11) and monosomy-7. She was diagnosed with Ph-positive ALL based on bone marrow examination, immunophenotyping, and cytogenetic analysis. She relapsed after treatment with the persistence of the Ph chromosome and the appearance of a monosomy-7.

Genetic Biomarkers in Chronic Myeloid Leukemia: What Have We Learned So Far?

Chronic Myeloid Leukemia (CML) is a rare malignant proliferative disease of the hematopoietic system, whose molecular hallmark is the Philadelphia chromosome (Ph). The Ph chromosome originates an aberrant fusion gene with abnormal kinase activity, leading to the buildup of reactive oxygen species and genetic instability of relevance in disease progression. Several genetic abnormalities have been correlated with CML in the blast phase, including chromosomal aberrations and common altered genes. Some of these genes are involved in the regulation of cell apoptosis and proliferation, such as the epidermal growth factor receptor (EGFR), tumor protein p53 (TP53), or Schmidt-Ruppin A-2 proto-oncogene (SRC); cell adhesion, e.g., catenin beta 1 (CTNNB1); or genes associated to TGF-β, such as SKI like proto-oncogene (SKIL), transforming growth factor beta 1 (TGFB1) or transforming growth factor beta 2 (TGFB2); and TNF-α pathways, such as Tumor necrosis factor (TNFA) or Nuclear factor kappa B subunit 1 (NFKB1). The involvement of miRNAs in CML is also gaining momentum, where dysregulation of some critical miRNAs, such as miRNA-451 and miRNA-21, which have been associated to the molecular modulation of pathogenesis, progression of disease states, and response to therapeutics. In this review, the most relevant genomic alterations found in CML will be addressed.

Integrated Genomic Analysis Identifies ANKRD36 Gene as a Novel and Common Biomarker of Disease Progression in Chronic Myeloid Leukemia

Simple Summary

Chronic myeloid leukemia is a type of blood cancer that is regarded as a success story in determining the exact biological origin, pathogenesis and development of a molecularly targeted (mutation-specific) therapy that has led to successful treatment of this fatal cancer. It is caused by the BCR-ABL fusion gene, which is formed from the translocation between chromosomes 9 and 22. Anti-BCR-ABL drugs, known as tyrosine kinase inhibitors (TKIs), have led to long-term remissions in more than 80% of CML patients and even cure in about one-third of patients. Nevertheless, many patients face drug resistance, and disease progression occurs in about 30% of CML patients, leading to morbidities and mortality. Unfortunately, no biomarkers of CML progression are available due to a poor understanding of the mechanism of progression. Therefore, finding reliable molecular biomarkers of CML progression is one of the most attractive research areas in 21st-century cancer research. In this study, we report novel genomic variants exclusively found in all our advanced-phase CML patients. This study will help in identifying CML patients at risk of disease progression and timely therapeutic interventions to avoid or at least delay fatal disease progression in this cancer.

Abstract

Background: Chronic myeloid leukemia (CML) is initiated in bone marrow due to chromosomal translocation t(9;22) leading to fusion oncogene BCR-ABL. Targeting BCR-ABL by tyrosine kinase inhibitors (TKIs) has changed fatal CML into an almost curable disease. Despite that, TKIs lose their effectiveness due to disease progression. Unfortunately, the mechanism of CML progression is poorly understood and common biomarkers for CML progression are unavailable. This study was conducted to find novel biomarkers of CML progression by employing whole-exome sequencing (WES). Materials and Methods: WES of accelerated phase (AP) and blast crisis (BC) CML patients was carried out, with chronic-phase CML (CP-CML) patients as control. After DNA library preparation and exome enrichment, clustering and sequencing were carried out using Illumina platforms. Statistical analysis was carried out using SAS/STAT software version 9.4, and R package was employed to find mutations shared exclusively by all AP-/BC-CML patients. Confirmation of mutations was carried out using Sanger sequencing and protein structure modeling using I-TASSER followed by mutant generation and visualization using PyMOL. Results: Three novel genes (ANKRD36, ANKRD36B and PRSS3) were mutated exclusively in all AP-/BC-CML patients. Only ANKRD36 gene mutations (c.1183_1184 delGC and c.1187_1185 dupTT) were confirmed by Sanger sequencing. Protein modeling studies showed that mutations induce structural changes in ANKRD36 protein. Conclusions: Our studies show that ANKRD36 is a potential common biomarker and drug target of early CML progression. ANKRD36 is yet uncharacterized in humans. It has the highest expression in bone marrow, specifically myeloid cells. We recommend carrying out further studies to explore the role of ANKRD36 in the biology and progression of CML.

DNAzymes, Novel Therapeutic Agents in Cancer Therapy: A Review of Concepts to Applications

The past few decades have witnessed a rapid evolution in cancer drug research which is aimed at developing active biological interventions to regulate cancer-specific molecular targets. Nucleic acid-based therapeutics, including ribozymes, antisense oligonucleotides, small interference RNA (siRNA), aptamer, and DNAzymes, have emerged as promising candidates regulating cancer-specific genes at either the transcriptional or posttranscriptional level. Gene-specific catalytic DNA molecules, or DNAzymes, have shown promise as a therapeutic intervention against cancer in various in vitro and in vivo models, expediting towards clinical applications. DNAzymes are single-stranded catalytic DNA that has not been observed in nature, and they are synthesized through in vitro selection processes from a large pool of random DNA libraries. The intrinsic properties of DNAzymes like small molecular weight, higher stability, excellent programmability, diversity, and low cost have brought them to the forefront of the nucleic acid-based therapeutic arsenal available for cancers. In recent years, considerable efforts have been undertaken to assess a variety of DNAzymes against different cancers. However, their therapeutic application is constrained by the low delivery efficiency, cellular uptake, and target detection within the tumour microenvironment. Thus, there is a pursuit to identify efficient delivery methods in vivo before the full potential of DNAzymes in cancer therapy is realized. In this light, a review of the recent advances in the use of DNAzymes against cancers in preclinical and clinical settings is valuable to understand its potential as effective cancer therapy. We have thus sought to firstly provide a brief overview of construction and recent improvements in the design of DNAzymes. Secondly, this review stipulates the efficacy, safety, and tolerability of DNAzymes developed against major hallmarks of cancers tested in preclinical and clinical settings. Lastly, the recent advances in DNAzyme delivery systems along with the challenges and prospects for the clinical application of DNAzymes as cancer therapy are also discussed.

Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia with e1a3 BCR-ABL1 transcript in a Nigerian with sickle cell anemia: a case report

Background

The occurrence of acute leukemia in patients with sickle cell anemia is uncommon. The Philadelphia chromosome is the hallmark of chronic myeloid leukemia. However, it may also be associated with acute lymphoblastic leukemia and acute myeloblastic leukemia. The common BCR-ABL1 transcripts seen in acute lymphoblastic leukemia are e1a2, e13a2, and e14a2, while other transcripts such as e1a3, e13a3, and e6a2 occur rarely. This report describes the presentation, management, and outcome of the occurrence of B-cell acute lymphoblastic leukemia with the rare e1a3 BCR-ABL1 transcript in a patient with sickle cell anemia.

Case presentation

A 19-year-old male Nigerian, a known sickle cell anemia patient was admitted on account of severe vaso-occlusive crisis. Examination revealed fever, palor, and jaundice. Full blood count showed anemia and leukocytosis. Peripheral blood and bone marrow smears revealed numerous large and small lymphoblasts in keeping with the L2 subtype of acute lymphoblastic leukemia based on the French–American–British classification. Further evaluation was in keeping with a diagnosis of BCR-ABL1-positive mature B-cell acute lymphoblastic leukemia associated with the rare e1a3 transcript. He was commenced simultaneously on induction chemotherapy and Imatinib while being prepared for allogeneic stem cell transplantation. However, he died  six  months after diagnosis from meningoencephalitis.

Conclusion

The occurrence of acute lymphoblastic leukemia with a rare BCR-ABL1 e1a3 transcript in association with sickle cell anemia is uncommon and associated with poor prognosis.

The role of proteomics in the multiplexed analysis of gene alterations in human cancer

INTRODUCTION

Proteomics has played a pivotal role in identifying proteins perturbed in disease conditions when compared with healthy samples. Study of dysregulated proteins aids in identifying diagnostic markers and potential therapeutic targets. Cancer is an outcome of interplay of several such disarrayed proteins and molecular pathways which perturb cellular homeostasis, resulting in transformation. In this review, we discuss various facets of proteomic approaches, including tools and technological advancements, aiding in understanding differentially expressed molecules and signaling mechanisms.

AREAS COVERED

In this review, we have taken the approach of documenting the different methods of proteomic studies, ranging from labeling techniques, data analysis methods, and the nature of molecule detected. We summarize each technique and provide a glimpse of cancer research carried out using them, highlighting the advantages and drawbacks in comparison with others. Literature search using online resources, such as PubMed and Google Scholar were carried out for this approach.

EXPERT OPINION

Technological advancements in proteomics studies have come a long way from the study of two-dimensional mapping of proteins separated on gels in the early 1970s. Higher precision in molecular identification and quantification (high throughput), and greater number of samples analyzed have been the focus of researchers.

Resistance to Tyrosine Kinase Inhibitors in Chronic Myeloid Leukemia-From Molecular Mechanisms to Clinical Relevance

Simple Summary

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasia associated with a molecular alteration, the fusion gene BCR-ABL1, that encodes the tyrosine kinase oncoprotein BCR-ABL1. This led to the development of tyrosine kinase inhibitors (TKI), with Imatinib being the first TKI approved. Although the vast majority of CML patients respond to Imatinib, resistance to this targeted therapy contributes to therapeutic failure and relapse. Here we review the molecular mechanisms and other factors (e.g., patient adherence) involved in TKI resistance, the methodologies to access these mechanisms, and the possible therapeutic approaches to circumvent TKI resistance in CML.

Abstract

Resistance to targeted therapies is a complex and multifactorial process that culminates in the selection of a cancer clone with the ability to evade treatment. Chronic myeloid leukemia (CML) was the first malignancy recognized to be associated with a genetic alteration, the t(9;22)(q34;q11). This translocation originates the BCR-ABL1 fusion gene, encoding the cytoplasmic chimeric BCR-ABL1 protein that displays an abnormally high tyrosine kinase activity. Although the vast majority of patients with CML respond to Imatinib, a tyrosine kinase inhibitor (TKI), resistance might occur either de novo or during treatment. In CML, the TKI resistance mechanisms are usually subdivided into BCR-ABL1-dependent and independent mechanisms. Furthermore, patients’ compliance/adherence to therapy is critical to CML management. Techniques with enhanced sensitivity like NGS and dPCR, the use of artificial intelligence (AI) techniques, and the development of mathematical modeling and computational prediction methods could reveal the underlying mechanisms of drug resistance and facilitate the design of more effective treatment strategies for improving drug efficacy in CML patients. Here we review the molecular mechanisms and other factors involved in resistance to TKIs in CML and the new methodologies to access these mechanisms, and the therapeutic approaches to circumvent TKI resistance.

Use of the «BCR/ABL - multitest» kit in the algorithm of laboratory diagnostics of oncohematological diseases: economic aspects

Abnormal mRNAs of the hybrid BCR-ABL gene in the majority of cases initiate the synthesis of proteins with a mass of 210 kDa (p210), 190 kDa (p190), and 230 kDa (p230). Expression of the p210 variant is most common in CML (95% of cases), while the p190 and p230 variants are less common (1-4%). On the contrary, p190 predominates in ALL. Measurement of BCR/ABL gene expression is included in clinical guidelines for the diagnosis of CML and ALL as sequential tests in accordance with their occurrence. At the same time, in the context of primary patients testing with suspected hematological malignancies with a low prevalence of BCR-ABL positive patients in the cohort of examined individuals, sequential testing is associated with low cost-effectiveness. Purpose: approbation of a parallel algorithm for detecting all three (p210, p190 and p230) using the multiplex RT-PCR format implemented in the «BCR/ABL-MULTITEST» reagent kit. We used anonymized blood samples from patients with suspected CML, as well as samples from ALL patients before starting therapy. Testing of blood samples was carried out using two variants of the algorithm: sequential determination of individual BCR-ABL transcripts and parallel determination using the developed set of reagents «BCR/ABL-MULTITEST». To detect the p210 transcript, a commercial kit «AmpliSens® Leukemia Quantum M-bcr-FRT» (Central Research Institute of Epidemiology of Rospotrebnadzor, Russia) was used. Simultaneously, a test was used to detect all three variants of BCR-ABL transcripts using the «BCR/ABL - MULTITEST» reagent kit based on a monochrome multiplex reaction «in one test tube». Reverse transcription were carried out using the REVERTA-L reagent kit (Central Research Institute of Epidemiology of Rospotrebnadzor, Russia) in accordance with the manufacturer's instructions. Using the reagent kits «BCR/ABL-MULTITEST» and «AmpliSens® Leukemia Quantum M-bcr-FRT» there is a high level of correlation of quantitative results of determining the chimeric transcript BCR-ABL р210 (r = 0.99). When using the proposed parallel algorithm with the primary use of the «BCR/ABL-MULTITEST» reagent kit, out of 95 patients with suspected CML, 9 samples with p210 transcript were identified, one with p190 BCR / ABL, and in one case a transcript variant characteristic of chronic neutrophilic leukemia - p230 BCR / ABL. The estimated cost for detecting one positive case of BCR-ABL when using the parallel diagnostic algorithm «BCR/ABL-MULTITEST» with a focused flow of studies is reduced by about 2 times due to a decrease in the amount of laboratory plastic used and the volume of the reaction mixture, as well as the absence of the need for repeated separate tests to detect p190 and p230. The use of the multiplex PCR-RT test system «BCR/ABL-MULTITEST» allows detecting in one test tube all three main variants of BCR-ABL transcripts - p210, p190, p230 and achieving significant resource savings when examining a cohort of patients with suspected CML and ALL and low frequency of positive samples.

Detection of mutations in CML patients resistant to tyrosine kinase inhibitor: imatinib mesylate therapy

Imatinib mesylate, a tyrosine kinase inhibitor, is the first choice in chronic myeloid leukemia treatment. However, resistance to imatinib may develop with time and in some cases, patients may not respond at all to imatinib. Progressive resistance to imatinib therapy is often due to mutations in the BCR/ABL region. Within the scope of our study 124 patients were evaluated via pyrosequencing between 2015 and 2020. In this regard, 32 patients who have a partial response and have no response to imatinib therapy were included in the study. In addition, next-generation sequencing (NGS) analysis was performed on 15 patients who were resistant to imatinib treatment according to the molecular follow-up reports. With pyrosequencing, 5 cases out of a total of 124 were found to be positive. This means that approximately 4.03% of the proportion is positive. But when we examined only 32 patients who have a partial response and have no response to imatinib therapy this rate is rising 15.6%. NGS analysis was performed with 15 patients who have no mutation with pyrosequencing of 32 patients and VUS (Variant of Uncertain Significance) mutation was detected in one. In this study, our aim was to determine the mutations of the BCR/ABL and to evaluate the mutations by NGS and pyrosequencing. Our study is important in terms of comparing the pyrosequencing with NGS mutation rates, drawing attention to the clinical importance of log reduction.

DNA damage in cancer development: special implications in viral oncogenesis

DNA lesions arise from a combination of physiological/metabolic sources and exogenous environmental influences. When left unrepaired, these alterations accumulate in the cells and can give rise to mutations that change the function of important proteins (i.e. tumor suppressors, oncoproteins), or cause chromosomal rearrangements (i.e. gene fusions) that also result in the deregulation of key cellular molecules. Progressive acquisition of such genetic changes promotes uncontrolled cell proliferation and evasion of cell death, and hence plays a key role in carcinogenesis. Another less-studied consequence of DNA damage accumulating in the host genome is the integration of oncogenic DNA viruses such as Human papillomavirus, Merkel cell polyomavirus, and Hepatitis B virus. This critical step of viral-induced carcinogenesis is thought to be particularly facilitated by DNA breaks in both viral and host genomes. Therefore, the impact of DNA damage on carcinogenesis is magnified in the case of such oncoviruses via the additional effect of increasing integration frequency. In this review, we briefly present the various endogenous and exogenous factors that cause different types of DNA damage. Next, we discuss the contribution of these lesions in cancer development. Finally, we examine the amplified effect of DNA damage in viral-induced oncogenesis and summarize the limited data existing in the literature related to DNA damage-induced viral integration. To conclude, additional research is needed to assess the DNA damage pathways involved in the transition from viral infection to cancer. Discovering that a certain DNA damaging agent increases the likelihood of viral integration will enable the development of prophylactic and therapeutic strategies designed specifically to prevent such integration, with an ultimate goal of reducing or eliminating these viral-induced malignancies.

The Relevance of Aurora Kinase Inhibition in Hematological Malignancies

Aurora kinases are a family of serine/threonine protein kinases that play a central role in eukaryotic cell division. Overexpression of aurora kinases in cancer and their role as major regulators of the cell cycle quickly inspired the idea that their inhibition might be a potential pathway when treating oncologic patients. Over the past couple of decades, the search for designing and testing of molecules capable of inhibiting aurora activities fueled many pre-clinical and clinical studies. In this study, data from the past 10 years of in vitro and in vivo investigations, as well as clinical trials, utilizing aurora kinase inhibitors as therapeutics for hematological malignancies were compiled and discussed, aiming to highlight potential uses of these inhibitors as a novel monotherapy model or alongside conventional chemotherapies. While there is still much to be elucidated, it is clear that these kinases play a key role in oncogenesis, and their manageable toxicity and potentially synergistic effects still render them a focus of interest for future investigations in combinatorial clinical trials.

Myeloid-Derived Suppressor Cells and Mesenchymal Stem/Stromal Cells in Myeloid Malignancies

Myeloid malignancies arise from an altered hematopoietic stem cell and mainly comprise acute myeloid leukemia, myelodysplastic syndromes, myeloproliferative malignancies, and chronic myelomonocytic leukemia. Myeloid neoplastic leukemic cells may influence the growth and differentiation of other hematopoietic cell lineages in peripheral blood and bone marrow. Myeloid-derived suppressor cells (MDSCs) and mesenchymal stromal cells (MSCs) display immunoregulatory properties by controlling the innate and adaptive immune systems that may induce a tolerant and supportive microenvironment for neoplasm development. This review analyzes the main features of MDSCs and MSCs in myeloid malignancies. The number of MDSCs is elevated in myeloid malignancies exhibiting high immunosuppressive capacities, whereas MSCs, in addition to their immunosuppression contribution, regulate myeloid leukemia cell proliferation, apoptosis, and chemotherapy resistance. Moreover, MSCs may promote MDSC expansion, which may mutually contribute to the creation of an immuno-tolerant neoplasm microenvironment. Understanding the implication of MDSCs and MSCs in myeloid malignancies may favor their potential use in immunotherapeutic strategies.

Myeloid-Derived Suppressor Cells and Mesenchymal Stem/Stromal Cells in Myeloid Malignancies

Myeloid malignancies arise from an altered hematopoietic stem cell and mainly comprise acute myeloid leukemia, myelodysplastic syndromes, myeloproliferative malignancies, and chronic myelomonocytic leukemia. Myeloid neoplastic leukemic cells may influence the growth and differentiation of other hematopoietic cell lineages in peripheral blood and bone marrow. Myeloid-derived suppressor cells (MDSCs) and mesenchymal stromal cells (MSCs) display immunoregulatory properties by controlling the innate and adaptive immune systems that may induce a tolerant and supportive microenvironment for neoplasm development. This review analyzes the main features of MDSCs and MSCs in myeloid malignancies. The number of MDSCs is elevated in myeloid malignancies exhibiting high immunosuppressive capacities, whereas MSCs, in addition to their immunosuppression contribution, regulate myeloid leukemia cell proliferation, apoptosis, and chemotherapy resistance. Moreover, MSCs may promote MDSC expansion, which may mutually contribute to the creation of an immuno-tolerant neoplasm microenvironment. Understanding the implication of MDSCs and MSCs in myeloid malignancies may favor their potential use in immunotherapeutic strategies.

A pediatric BAL case with double Ph chromosomes and trisomy 5

Biphenotypic acute leukemias (BAL) are known as a type of leukemia involving cells with myeloid and along with lymphoid origin, in which genomic changes are detected. It has been stated that the most common genomic changes in BAL are t(9;22) and the translocations of the 11q23 region, these anomalies cause poor prognostic effects. We detected trisomy 5 (+5) in addition to the double Ph chromosome in a case where we investigated the genomic changes using molecular and conventional cytogenetic methods. Bone marrow transplantation was planned due to the poor response to prednisone. According to the information we have obtained, our report will be the first article to discuss the aberrations found in addition to the Ph chromosome in BAL and the effect of these aberrations on prognosis. However, the double observation of the Ph chromosome, which has a poor prognostic effect, is expected to affect the prognosis more negatively, this case will contribute to the literature in terms of trisomy 5. We think that more case reports are needed to reveal the anomalies and their prognostic significance in BAL.

Vitamin E TPGS 1000 Induces Apoptosis in the K562 Cell Line: Implications for Chronic Myeloid Leukemia

Chronic myeloid leukemia (CML) is a hematologic malignancy derived from the myeloid lineage molecularly characterized by t(9;22)(q34;q11) resulting in BCR-ABL1 gene fusion, which is known as Philadelphia (Ph) chromosome. Although tyrosine kinase inhibitors (TKIs) have restored and maintained the quality of life of patients with CML, an important minority of patients become resistant to first-and-second-generation TKIs and require an alternative treatment. The K562 cell (Ph+, p53-/-) line was treated with Vit E TPGS 1000 (20-80 μM) only or with other products of interest (e.g., antioxidant N-acetylcysteine (NAC), specific JNK and caspase-3 inhibitor SP600125, and NSCSI, respectively) for 24 h at 37°C. Cells were analyzed by fluorescence microscopy (FM), flow cytometry (FC), and Western blotting (WB) techniques. We show that TPGS induces apoptosis in K562 cells through H₂O₂ signaling mechanism comprising the activation of a minimal molecular cascade: the kinase JNK>the transcription factor c-JUN>the activation of BCL-only BH3 proapoptotic protein PUMA>loss of mitochondrial membrane potential (ΔΨ _m)>activation of caspase-3>chromatin condensation>fragmentation of DNA. Additionally, TPGS oxidizes the stress sensor protein DJ-1-Cys106-SH into DJ-1-Cys106-SO₃ and arrested the cell cycle in the S phase. Remarkably, NAC, SP600125, and NSCSI blocked TPGS-induced OS and apoptosis in K562. Since TPGS is safe in mice and humans, it is especially promising for preclinical and clinical CML leukemia research. Our findings support the view that oxidation therapy offers an important opportunity to eliminate CML.

Multi-Omics Model Applied to Cancer Genetics

In this review, we focus on bioinformatic oncology as an integrative discipline that incorporates knowledge from the mathematical, physical, and computational fields to further the biomedical understanding of cancer. Before providing a deeper insight into the bioinformatics approach and utilities involved in oncology, we must understand what is a system biology framework and the genetic connection, because of the high heterogenicity of the backgrounds of people approaching precision medicine. In fact, it is essential to providing general theoretical information on genomics, epigenomics, and transcriptomics to understand the phases of multi-omics approach. We consider how to create a multi-omics model. In the last section, we describe the new frontiers and future perspectives of this field.

Anti-Leukemic Properties of Aplysinopsin Derivative EE-84 Alone and Combined to BH3 Mimetic A-1210477

Aplysinopsins are a class of marine indole alkaloids that exhibit a wide range of biological activities. Although both the indole and N-benzyl moieties of aplysinopsins are known to possess antiproliferative activity against cancer cells, their mechanism of action remains unclear. Through in vitro and in vivo proliferation and viability screening of newly synthesized aplysinopsin analogs on myelogenous leukemia cell lines and zebrafish toxicity tests, as well as analysis of differential toxicity in noncancerous RPMI 1788 cells and PBMCs, we identified EE-84 as a promising novel drug candidate against chronic myeloid leukemia. This indole derivative demonstrated drug-likeness in agreement with Lipinski’s rule of five. Furthermore, EE-84 induced a senescent-like phenotype in K562 cells in line with its cytostatic effect. EE-84-treated K562 cells underwent morphological changes in line with mitochondrial dysfunction concomitant with autophagy and ER stress induction. Finally, we demonstrated the synergistic cytotoxic effect of EE-84 with a BH3 mimetic, the Mcl-1 inhibitor A-1210477, against imatinib-sensitive and resistant K562 cells, highlighting the inhibition of antiapoptotic Bcl-2 proteins as a promising novel senolytic approach against chronic myeloid leukemia.

VNTR polymorphism in the breakpoint region of ABL1 and susceptibility to bladder cancer

BACKGROUND

ABL1 is primarily known as a leukemia-related oncogene due to translocation, but about 2.2% of ABL1 mutations have been identified in bladder cancer, and high expression in solid cancer has also been detected.

METHODS

Here, we used the NCBI database, UCSC genome browser gateway and Tandem repeat finder program to investigate the structural characterization of the ABL1 breakpoint region and to identify the variable number of tandem repeats (VNTR). To investigate the relationship between ABL1-MS1 and bladder cancer, a case-controlled study was conducted in 207 controls and 197 bladder cancer patients. We also examined the level of transcription of the reporter gene driven by the ABL1 promoter to determine if the VNTR region affects gene expression.

RESULTS

In our study, one VNTR was identified in the breakpoint region, the intron 1 region of ABL1, and was named ABL1-MS1. In the control group, only two common alleles (TR13, TR15) were detected, but an additional two rare alleles (TR14, TR16) were detected in bladder cancer. A statistically significant association was identified between the rare ABL1-MS1 allele and bladder cancer risk: P = 0.013. Investigating the level of transcription of the reporter gene driven by the ABL1 promoter, VNTR showed inhibition of ABL1 expression in non-cancer cells 293 T, but not in bladder cancer cells. In addition, ABL1-MS1 was accurately passed on to offspring according to Mendelian inheritance through meiosis.

CONCLUSIONS

Therefore, the ABL1-MS1 region can affect ABL1 expression of bladder cancer. This study provides that ABL1-MS1 can be used as a DNA fingerprinting marker. In addition, rare allele detection can predict susceptibility to bladder cancer.

[Experience of the Spanish Group for Hematopoietic Transplantation (GETMON-GETH) in allogenic hematopoietic stem cell transplantation in Philadelphia acute lymphoblastic leukemia]

INTRODUCTION

Outcomes in patients diagnosed of acute lymphoblastic leukemia with Philadelphia chromosome (Ph-ALL) remains unfavourable compared to other subtypes of acute lymphoblastic leukemia despite improvements in drug treatments as well as advances in hematopoietic stem cell transplantation (HSCT).

PATIENTS AND METHODS

The role of allogeneic HSCT in Ph-ALL patients has been analysed through a multicentric study where data belonging to 70 patients diagnosed of this entity in different center that received HSCT between years 1998 and 2014, were reported by the Grupo Español de Trasplante Hematopoyético (GETH).

RESULTS

The performance of HSCT from year 2004, in first complete remission (CR) status with thymoglobulin (ATG) based conditioning had a favorable impact on overall survival (OS). HSTC performance from year 2004, in first CR with ATG-based conditioning in addition to acute graft versus host disease (aGvHD) development, increased event free survival (EFS). Treatment with imatinib as well as undetectable minimal residual disease (MRD) prior to HSCT, combined with aGvHD, reduced risk of relapse (RR). Patient age less than 10 years when HSCT, first CR and ATG-based conditioning were associated to a lower transplant related mortality (TRM).

CONCLUSIONS

Patients that could achieve first CR that also received ATG-based conditioning had a better OS and EFS, so HSCT should be considered for this group of patients.

Interplay between genome organization and epigenomic alterations of pericentromeric DNA in cancer

In eukaryotic genome biology, the genomic organization inside the three-dimensional (3D) nucleus is highly complex, and whether this organization governs gene expression is poorly understood. Nuclear lamina (NL) is a filamentous meshwork of proteins present at the lining of inner nuclear membrane that serves as an anchoring platform for genome organization. Large chromatin domains termed as lamina-associated domains (LADs), play a major role in silencing genes at the nuclear periphery. The interaction of the NL and genome is dynamic and stochastic. Furthermore, many genes change their positions during developmental processes or under disease conditions such as cancer, to activate certain sorts of genes and/or silence others. Pericentromeric heterochromatin (PCH) is mostly in the silenced region within the genome, which localizes at the nuclear periphery. Studies show that several genes located at the PCH are aberrantly expressed in cancer. The interesting question is that despite being localized in the pericentromeric region, how these genes still manage to overcome pericentromeric repression. Although epigenetic mechanisms control the expression of the pericentromeric region, recent studies about genome organization and genome-nuclear lamina interaction have shed light on a new aspect of pericentromeric gene regulation through a complex and coordinated interplay between epigenomic remodeling and genomic organization in cancer.

The Binary Classification of Protein Kinases

In an earlier publication a binary model for chronic diseases classification has been proposed. According to the model, chronic diseases were classified as “high Treg” or “low Treg” diseases, depending on whether the immune response is anti- or pro-inflammatory and assuming that regulatory T cells are major determinants of the response. It turned out that most cancers are “high Treg” diseases, while autoimmune diseases are “low Treg”. This paper proposes a molecular cause for this binary response. The mechanism proposed depends on the effect of protein kinases on the immune system. Thus, protein kinases are classified as anti- or pro-inflammatory kinases depending on whether they drive “high Treg” or “low Treg” diseases. Observations reported in the earlier publication can be described in terms of anti-inflammatory kinase (AIK) or pro-inflammatory kinase (PIK) activity. Analysis of literature data reveals that the two classes of kinases display distinctive properties relating to their interactions with pathogens and environmental factors. Pathogens that promote Treg activity (“high Treg” pathogens) activate AIKs, while pathogens that suppress Treg activity (“low Treg” pathogens) activate PIKs. Diseases driven by AIKs are associated with “high Treg” pathogens while those diseases driven by PIKs are associated with “low Treg” pathogens. By promoting the activity of AIKs, alcohol consumption increases the risk of “high Treg” cancers but decreases the risk of some “low Treg” autoimmune diseases. JAK1 gain-of-function mutations are observed at high frequencies in autoimmune diseases while JAK1 loss-of-function mutations are observed at high frequencies in cancers with high tumor-infiltrating Tregs. It should also be noted that the corresponding two classes of protein kinase inhibitors are mutually exclusive in terms of their approved therapeutic indications. There is no protein kinase inhibitor that is approved for the treatment of both autoimmune diseases and “high Treg” cancers. Although there are exceptions to the conclusions presented above, these conclusions are supported by the great bulk of published data. It therefore seems that the binary division of protein kinases is a useful tool for elucidating (at the molecular level) many distinctive properties of cancers and autoimmune diseases.

Chronic myeloid leukemia-from the Philadelphia chromosome to specific target drugs: A literature review

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm and was the first neoplastic disease associated with a well-defined genotypic anomaly - the presence of the Philadelphia chromosome. The advances in cytogenetic and molecular assays are of great importance to the diagnosis, prognosis, treatment, and monitoring of CML. The discovery of the breakpoint cluster region (BCR)-Abelson murine leukemia (ABL) 1 fusion oncogene has revolutionized the treatment of CML patients by allowing the development of targeted drugs that inhibit the tyrosine kinase activity of the BCR-ABL oncoprotein. Tyrosine kinase inhibitors (known as TKIs) are the standard therapy for CML and greatly increase the survival rates, despite adverse effects and the odds of residual disease after discontinuation of treatment. As therapeutic alternatives, the subsequent TKIs lead to faster and deeper molecular remissions; however, with the emergence of resistance to these drugs, immunotherapy appears as an alternative, which may have a cure potential in these patients. Against this background, this article aims at providing an overview on CML clinical management and a summary on the main targeted drugs available in that context.

Development of BCR-ABL1 Transgenic Zebrafish Model Reproducing Chronic Myeloid Leukemia (CML) Like-Disease and Providing a New Insight into CML Mechanisms

Zebrafish has proven to be a versatile and reliable experimental in vivo tool to study human hematopoiesis and model hematological malignancies. Transgenic technologies enable the generation of specific leukemia types by the expression of human oncogenes under specific promoters. Using this technology, a variety of myeloid and lymphoid malignancies zebrafish models have been described. Chronic myeloid leukemia (CML) is a clonal myeloproliferative neoplasia characterized by the BCR-ABL1 fusion gene, derived from the t (9;22) translocation causing the Philadelphia Chromosome (Ph). The BCR-ABL1 protein is a constitutively activated tyrosine kinas inducing the leukemogenesis and resulting in an accumulation of immature leukemic cells into bone marrow and peripheral blood. To model Ph+ CML, a transgenic zebrafish line expressing the human BCR-ABL1 was generated by the Gal4/UAS system, and then crossed with the hsp70-Gal4 transgenic line. The new line named (BCR-ABL1pUAS:CFP/hsp70-Gal4), presented altered expression of hematopoietic markers during embryonic development compared to controls and transgenic larvae showed proliferating hematopoietic cells in the caudal hematopoietic tissue (CHT). The present transgenic zebrafish would be a robust CML model and a high-throughput drug screening tool.

Drug Combination in Cancer Treatment-From Cocktails to Conjugated Combinations

It is well recognized today that anticancer drugs often are most effective when used in combination. However, the establishment of chemotherapy as key modality in clinical oncology began with sporadic discoveries of chemicals that showed antiproliferative properties and which as a first attempt were used as single agents. In this review we describe the development of chemotherapy from its origins as a single drug treatment with cytotoxic agents to polydrug therapy that includes targeted drugs. We discuss the limitations of the first chemotherapeutic drugs as a motivation for the establishment of combined drug treatment as standard practice in spite of concerns about frequent severe, dose limiting toxicities. Next, we introduce the development of targeted treatment as a concept for advancement within the broader field of small-molecule drug combination therapy in cancer and its accelerating progress that was boosted by recent scientific and technological progresses. Finally, we describe an alternative strategy of drug combinations using drug-conjugates for selective delivery of cytotoxic drugs to tumor cells that potentiates future improvement of drug combinations in cancer treatment. Overall, in this review we outline the development of chemotherapy from a pharmacological perspective, from its early stages to modern concepts of using targeted therapies for combinational treatment.

Tyrosine kinase inhibitor resistance: a case report on chronic myeloid leukemia and Gilbert's syndrome

Although tyrosine kinase inhibitors (TKI) are commonly used as targeted treatment options for chronic myeloid leukemia (CML), its use is associated to UGT1A1 polymorphisms and, consequently, are related to a higher risk of manifesting Gilbert's syndrome, a genetic disorder associated to hyperbilirubinemia. The report of concomitant condition of CML and Gilbert's Syndrome is uncommon. Therefore, the aim of this study was to report the clinical case of a patient diagnosed with CML and subsequently, with Gilbert's Syndrome. A 34-year-old female was diagnosed with CML. On physical examination, spleen and liver were palpable, indicating hepatosplenomegaly. Laboratory findings of peripheral blood showed leukocytosis (165,190/mm³), 6% of blasts and a bone marrow biopsy showed hypercellularity by granulocytic series with moderate maturation delay. After diagnosis, the patient immediately started chemotherapy with the TKI Imatinib. One year after treatment, due to the partial response, the therapy was changed to Nilotinib, resulting in a complete response. Despite the absence of hyperbilirubinemia, a genetic study by polymerase chain reaction (PCR) verified a positivity for Gilbert's Syndrome. TKIs are also inhibitors of the enzyme UDPGT1, leading to deficient glucuronidation, causing manifestation of Gilbert's Syndrome. This report demonstrates the case of a patient that, besides having two coexisting conditions that could cause hyperbilirubinemia, did not have bilirubin alterations and it highlights the importance of having genetic investigations in cancer patients, in order to identify secondary diseases that could worsen the course of treatment.

Vertebrate Chromosome Evolution

The study of chromosome evolution is undergoing a resurgence of interest owing to advances in DNA sequencing technology that facilitate the production of chromosome-scale whole-genome assemblies de novo. This review focuses on the history, methods, discoveries, and current challenges facing the field, with an emphasis on vertebrate genomes. A detailed examination of the literature on the biology of chromosome rearrangements is presented, specifically the relationship between chromosome rearrangements and phenotypic evolution, adaptation, and speciation. A critical review of the methods for identifying, characterizing, and visualizing chromosome rearrangements and computationally reconstructing ancestral karyotypes is presented. We conclude by looking to the future, identifying the enormous technical and scientific challenges presented by the accumulation of hundreds and eventually thousands of chromosome-scale assemblies.

Association of Chronic Myelogenous (Basophilic) Leukemia and the BCR/ABL Mutation in a Yucatan Barrow (Sus scrofa domestica)

Background: Chronic myelogenous leukemia (CML) is a clonal proliferative disorder of the myeloid, megakaryocyte, and erythroid lineages. The onset and subsequent progression of CML is well-described in humans. There is comparably little information surrounding CML progression in veterinary species, including Yucatan miniature swine that are common for preclinical pharmaceutical and device testing. In humans, more than 90% of CML cases are associated with a chromosomal translocation that results in the Philadelphia gene (BCR/ABL mutation). In this report, the presence of the Philadelphia gene in a Yucatan burrow was confirmed in white blood cells collected prior to onset of clinical signs with primers designed from the human BCR/ABL sequence. Case Presentation: A 24 month old, 70 kg, Yucatan barrow received a prefabricated bovine cortical bone xenograft following a unilateral zygomatic ostectomy for a preclinical study. Complete blood count and serum chemistries were performed prior to and 28, 53, 106, and 129 days after facial surgery. Fifty three days after surgery, a bone marrow biopsy was performed due to anorexia, severe basophilia, and mild anemia. A finding of a moderate increase in basophilic precursors in bone marrow cytology was followed by lymphocyte immunophenotyping via flow cytometry and RT-PCR amplification of the Philadelphia gene in white blood cell samples from the affected barrow and an unaffected barrow in the same treatment group. Bone marrow, lymph node, liver, spleen, lung, kidney, and adrenal gland lesions of mostly myeloblasts were identified after the affected barrow died 146 days after surgery. Flow cytometry confirmed lymphopenia and suggested basophilia, and RT-PCR established the presence of the BCR/ABL gene. Conclusions: The information in this report confirms the presence of the BCR/ABL mutation and documents progression of chronic myelogenous (basophilic) leukemia from a chronic phase to a terminal blast crisis in an adult Yucatan barrow. The natural occurrence and progression of CML associated with the BCR/ABL mutation in miniature swine establishes potential for future porcine models of human CML. The information also establishes a genetic test to confirm porcine CML to prevent inadvertent attribution of clinical signs to treatment complications during preclinical testing.

Distribution of BCR-ABL1 Transcript Variants in Nigerians with Chronic Myeloid Leukemia

The distribution of BCR-ABL1 transcript variants e13a2 ("b2a2") and e14a2 ("b3a2") in Nigerians with chronic myeloid leukemia (CML) had not been previously studied. In addition, there is paucity of data on the impact of BCR-ABL1 transcript variants on clinical presentation and survival in CML patients in Nigeria. The BCR-ABL1 transcript variants were analyzed in 230 Imatinib-treated CML patients at diagnosis. Patients with incomplete data (n = 28), e19a2 (n = 3) and e1a2 (n = 1) were excluded from analysis of transcript variant on disease presentation and survival leaving only 198. The frequencies of BCR-ABL1 transcript variants were 30 (13.0%), 114 (49.6%), 82 (35.7%), three (1.3%) and one (0.4%) for e13a2, e14a2, co-expression of e13a2/e14a2, e19a2 and e1a2, respectively. A significantly higher platelet count was found in patients with e13a2 variant (531.1 ± 563.4 × 10⁹/L) than in those expressing e14a2 (488.2 ± 560.3 × 10⁹/L) or e13a2/e14a2 (320.7 ± 215.8 × 10⁹/L); p = 0.03. No significant differences were found between the variants with regards to gender, age, phase of disease at diagnosis, total white blood cell count, neutrophil percentage, hematocrit, splenomegaly or hepatomegaly. Overall survival was higher but not statistically significant (p = 0.4) in patients with e14a2 variant (134 months) than in e13a2 (119 months) and co-expression of e13a2/e14a2 (115 months). Nigerian CML patients have the highest incidence of co-expression of e13a2 and e14a2. Distinct disease characteristics which contrast with findings from the Western countries were also identified in Nigerians which may be due to genetic factors.

Evaluation of Imatinib Concentrations in Samples Submitted for BCR-ABL1 or Imatinib Testing-Evidence to Support Therapeutic Drug Monitoring for Dose Optimization?

BACKGROUND

Imatinib is one of the first-line therapies for chronic myeloid leukemia. Achieving a major molecular response early in treatment, as indicated by a BCR-ABL1 major international scale result of ≤0.1% within 6 months, is associated with better patient outcomes and is statistically associated with a trough imatinib concentration of approximately 1000 ng/mL. Adherence to therapy, drug resistance, drug-drug interactions, and pharmacokinetic/pharmacodynamic factors may hinder attaining this target. Therapeutic drug monitoring of imatinib is not currently standard-of-care, but may help to evaluate adherence and optimize treatment of patients with chronic myeloid leukemia. This study aimed to evaluate imatinib concentrations in real-world patient plasma samples to identify the proportion of imatinib-treated patients who achieved the therapeutic target of 1000 ng/mL.

METHODS

This was a retrospective, observational study that measured imatinib in residual plasma samples used for BCR-ABL1 tests (n = 1022) and analyzed clinician-ordered imatinib tests for therapeutic drug monitoring (n = 116). Imatinib was measured by competitive immunoassay. The frequency of imatinib concentrations achieving the therapeutic target was determined and correlated with BCR-ABL1 major international scale, age, and sex.

RESULTS

Seventy-two percent of patients tested for BCR-ABL1 may not have been prescribed or were not adherent to imatinib therapy. In the 29% of patients who did not achieve major molecular response, but had quantifiable imatinib concentrations, the therapeutic concentration was not met. For clinician-ordered imatinib tests, 45% of samples did not exceed the therapeutic target and 4% had potentially toxic plasma concentrations (>3000 ng/mL).

CONCLUSIONS

Therapeutic drug monitoring for imatinib may assist clinicians in the identification of patients who may not be adherent to therapy, display variable pharmacokinetics or pharmacodynamics, or may be experiencing toxicity or treatment failure.

The Role of the Curcumin for Inducing Apoptosis in Acute Lymphoblastic Leukemia Cells: A Systematic Review

Acute lymphoblastic leukemia (ALL) is a hematological malignancy of lymphoid progenitor cells associated with excessive proliferation of lymphocytes. Curcumin, a polyphenolic compound, is known to possess anticancer activity. However, the mechanism of apoptosis induction differs in cancers. In this study, we discuss the potential apoptosis and anticancer effect of curcumin on the ALL. After choosing Medical Subject Headings (MeSH) keywords, including "Curcumin", "acute lymphoblastic leukemia", "apoptosis", as well as searching Medline/PubMed, Scopus, Sciencedirect. hand searching in key journals, list of references of selected articles and gray literature, without time and language limitation, articles up to December 2017 were entered into this review. In this review, 244 articles were acquired at the primary search. Study selection and quality assessment processes were done based on Cochrane library guidelines. According to six articles that were selected, curcumin could enhance the antitumor activity of chemotherapy drugs such as L-asparaginase. Curcumin induces apoptosis in Pre B- ALL and T- ALL cells by decreased NF-kB levels, increased p53 levels, PARP-1 cleavage. Also, the induction of growth-arrest and apoptosis in association with the blockade of constitutively active JAK-STAT pathway suggests this be a mechanism by curcumin. Curcumin could be used for the treatment of cancer like ALL.

The HDAC6 inhibitor 7b induces BCR-ABL ubiquitination and downregulation and synergizes with imatinib to trigger apoptosis in chronic myeloid leukemia

Despite the discovery of tyrosine kinase inhibitors (TKIs) for the treatment of breakpoint cluster region-Abelson (BCR-ABL)⁺ cancer types, patients with chronic myeloid leukemia (CML) treated with TKIs develop resistance and severe adverse effects. Combination treatment, especially with a histone deacetylase (HDAC) 6 inhibitor (HDAC6i), appears to be an attractive option to prevent TKI resistance, considering the potential capacity of an HDAC6i to diminish BCR-ABL expression. We first validated the in vivo anti-cancer potential of the compound 7b by significantly reducing the tumor burden of BALB/c mice xenografted with K-562 cells, without notable organ toxicity. Here, we hypothesize that the HDAC6i compound 7b can lead to BCR-ABL downregulation in CML cells and sensitize them to TKI treatment. The results showed that combination treatment with imatinib and 7b resulted in strong synergistic caspase-dependent apoptotic cell death and drastically reduced the proportion of leukemia stem cells, whereas this treatment only moderately affected healthy cells. Ultimately, the combination significantly decreased colony formation in a semisolid methylcellulose medium and tumor mass in xenografted zebrafish compared to each compound alone. Mechanistically, the combination induced BCR-ABL ubiquitination and downregulation followed by disturbance of key proteins in downstream pathways involved in CML proliferation and survival. Taken together, our results suggest that an HDAC6i potentiates the effect of imatinib and could overcome TKI resistance in CML cells.

Circular RNAs in Blood Malignancies

Circular (circ)RNAs influence a wide range of biological processes at least in part by interacting with proteins and microRNAs. CircRNAs expressed in the hematopoietic compartment have been increasingly recognized as modulators of physiological and pathological features of hematopoetic stem cell (HSC)-derived populations. In particular, several circRNAs were found to enhance or suppress tumor progression in blood malignancies such as leukemias and lymphomas. Moreover, numerous circRNAs have been proposed to help confer resistance to the conventional treatments used in hematopoietic cancers. Here, we review the most important circRNAs described thus far in acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), lymphomas, and multiple myeloma (MM). We discuss the usefulness of circRNAs as diagnostic and prognostic markers and their potential value as therapeutic targets.

Unilateral Macular Choroidal Neovascularization; a Rare Manifestation in Chronic Myelogenous Leukemia

Purpose:

To report a case of chronic myelogenous leukemia (CML) treatment with imatinib mesylate in the remission phase who developed unilateral macular choroidal neovascularization (CNV).

Methods:

A 45-year-old male marketer with a 5-year history of CML treated with imatinib mesylate presented with 2 months history of progressive vision loss and metamorphopsia in the right eye.

Results:

Fundus examination of the right eye revealed grey-white elevated retinal lesion with indistinct borders in the macula and retinal telangiectasia in the temporal macula. Fluorescein angiography (FA) and optical coherence tomography angiography (OCTA) confirmed the presence of CNV in the right eye. After treatment with anti-vascular endothelial growth factor (anti-VEGF), macular CNV regressed significantly.

Conclusion:

Macular CNV must be kept in mind as a rare ophthalmic manifestation of patients with CML under treatment with imatinib even in the remission phase.

Chronic Myeloid Leukemia: Atypical Presentation and Diagnostic Pitfall in the Workup of Isolated Thrombocytosis

Chronic myeloid leukemia (CML) is one of the classic types of myeloproliferative neoplasms. It typically manifests with leukocytosis, but rarely with isolated thrombocytosis. Here we describe a unique case of isolated thrombocytosis as an initial presentation of CML in a 21-year-old woman, where the BCR-ABL1 fusion gene was detected in bone marrow (BM) aspiration and biopsy specimen after a negative peripheral blood (PB) fluorescence in situ hybridization testing. It is crucial to pursue workup for patients with isolated thrombocytosis through testing for the presence of the BCR-ABL fusion gene or the Philadephia chromosome in both PB and the BM in order to distinguish CML from essential thrombocythemia.

Novel Gene Fusions in Glioblastoma Tumor Tissue and Matched Patient Plasma

Sequencing studies have provided novel insights into the heterogeneous molecular landscape of glioblastoma (GBM), unveiling a subset of patients with gene fusions. Tissue biopsy is highly invasive, limited by sampling frequency and incompletely representative of intra-tumor heterogeneity. Extracellular vesicle-based liquid biopsy provides a minimally invasive alternative to diagnose and monitor tumor-specific molecular aberrations in patient biofluids. Here, we used targeted RNA sequencing to screen GBM tissue and the matched plasma of patients (n = 9) for RNA fusion transcripts. We identified two novel fusion transcripts in GBM tissue and five novel fusions in the matched plasma of GBM patients. The fusion transcripts FGFR3-TACC3 and VTI1A-TCF7L2 were detected in both tissue and matched plasma. A longitudinal follow-up of a GBM patient with a FGFR3-TACC3 positive glioma revealed the potential of monitoring RNA fusions in plasma. In summary, we report a sensitive RNA-seq-based liquid biopsy strategy to detect RNA level fusion status in the plasma of GBM patients.

Association between CYP2B6 polymorphism and acute leukemia in a Han population of Northwest China

Background

The aim of this study was to investigate potential associations between CYP2B6 c.516G>T polymorphism and the occurrence and prognosis of acute leukemias (AL) in the Han population of Northwest China.

Methods

The CYP2B6 gene polymorphism was analyzed by PCR‐RFLP and Sanger DNA sequencing in 126 patients with AL and 161 healthy controls.

Results

Compared with controls, there were significantly higher frequencies of GT and TT genotypes and T alleles in AL patients (p < .05), particularly in fusion gene‐positive AL patients. There was no significant difference in CYP2B6 polymorphic genotypes and T alleles between AL patients with complete remission after the first course of chemotherapy and controls (p > .05), while the frequencies in AL patients with partial remission and no remission were significantly higher. The CYP2B6 allele frequency in Han Chinese in Northwest China was significantly different to that reported in Han Chinese and other ethnic minorities in southern China, Uygur Chinese, Vietnamese, African, German, British, Spanish, Turkish, and Argentinian populations; however, there was no significant difference compared with allele frequencies reported in Tibetan and Mongolian Chinese, Japanese, Korean, and American populations.

Conclusion

Our findings show a strong correlation of the CYP2B6 c.516G>T polymorphism in the Han population of Northwest China with AL, especially fusion gene‐positive AL, and indicate a poor prognosis after the first course of chemotherapy. Our findings also implicate the T allele in AL susceptibility and indicate the existence of racial and geographical differences in allele frequencies of CYP2B6 c.516G>T polymorphism.

HDAC6-an Emerging Target Against Chronic Myeloid Leukemia?

Imatinib became the standard treatment for chronic myeloid leukemia (CML) about 20 years ago, which was a major breakthrough in stabilizing the pathology and improving the quality of life of patients. However, the emergence of resistance to imatinib and other tyrosine kinase inhibitors leads researchers to characterize new therapeutic targets. Several studies have highlighted the role of histone deacetylase 6 (HDAC6) in various pathologies, including cancer. This protein effectively intervenes in cellular activities by its primarily cytoplasmic localization. In this review, we will discuss the molecular characteristics of the HDAC6 protein, as well as its overexpression in CML leukemic stem cells, which make it a promising therapeutic target for the treatment of CML.

Drug Resistance Biomarkers and Their Clinical Applications in Childhood Acute Lymphoblastic Leukemia

Biomarkers are biological molecules found in body fluids or tissues, which can be considered as indications of a normal or abnormal process, or of a condition or disease. There are various types of biomarkers based on their application and molecular alterations. Treatment-sensitivity or drug resistance biomarkers include prognostic and predictive molecules with utmost importance in selecting appropriate treatment protocols and improving survival rates. Acute lymphoblastic leukemia (ALL) is the most prevalent hematological malignancy diagnosed in children with nearly 80% cure rate. Despite the favorable survival rates of childhood ALL (chALL), resistance to chemotherapeutic agents and, as a consequence, a dismal prognosis develops in a significant number of patients. Therefore, there are urgent needs to have robust, sensitive, and disease-specific molecular prognostic and predictive biomarkers, which could allow better risk classification and then better clinical results. In this article, we review the currently known drug resistance biomarkers, including somatic or germ line nucleic acids, epigenetic alterations, protein expressions and metabolic variations. Moreover, biomarkers with potential clinical applications are discussed.

Diarylamides in anticancer drug discovery: A review of pre-clinical and clinical investigations

Several diarylamide compounds have been highlighted as potential anticancer agents. Among them, imatinib, dasatinib, and nilotinib have been marketed for treatment of chronic myeloid leukemia (CML). CML is a cancer type that originates in specific cells in bone marrow and is considered as life-threating disease. Imatinib is the first generation of tyrosine kinase inhibitor (TKI) to be approved for treatment of CML. Second generation drugs, dasatinib and nilotinib, were introduced for patients that are resistant or intolerant to imatinib therapy. Second generation drugs induce faster responses with fewer side effects when compared to imatinib. In this literature review, we reviewed recent advances of diarylamide anticancer agents, including first and second generation drugs treating CML and their other uses, in addition to other compounds that are still in preclinical phases. This review focuses on the reports published in the literature from 2010 to 2019.

Impact of Additional Chromosomal Aberrations Present at Diagnosis on Outcome of Adolescent and Young Adult Chronic Myeloid Leukemia Patients: A Single Center Experience

Studying the influence of additional chromosomal aberrations (ACAs) present at diagnosis on the outcome of adolescent and young adult (AYA) chronic myeloid leukemia (CML) patients as it has not been addressed previously. Eighty-six AYA CML patients have been analyzed for occurrence of ACAs at diagnosis through performing bone marrow karyotyping. All patients received imatinib mesylate upon diagnosis of CML. Overall response, molecular response, survival status, progression and occurrence of events were monitored during the follow up period. There was a statistically significant difference between patients with and without ACAs regarding overall response (P = 0.049). There was insignificant difference between the two groups regarding achievement of major molecular response (MMR) (P = 0.594), MR⁴ (P = 0.282) and MR^4.5 (P = 0.704). There was a significant difference between patients with and without ACAs regarding time to MMR (P = 0.042) and time to MR⁴ (P = 0.048) but not regarding time to MR^4.5 (P = 0.065). There was insignificant impact of ACAs at diagnosis on overall survival (P = 0.152), progression free survival (P = 0.112), failure free survival (P = 0.114), event free survival (P = 0.194) and alternative treatment free survival (P = 0.731). The presence of ACAs at diagnosis does not signal worse prognosis in AYA CML patients but it may delay molecular response to imatinib mesylate.

Detection of Novel Fusion Transcript VTI1A-CFAP46 in Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is now the second-highest cause of cancer death worldwide. Recent studies have discovered a wide range of somatic mutations in HCC. These mutations involve various vital signaling pathways such as: Wnt/β-Catenin, p53, telome-rase reverse transcriptase (TERT), chromatin remodeling, RAS/MAPK signaling, and oxidative stress. However, fusion transcripts have not been broadly explored in HCC.

Methods

To identify novel fusion transcripts in HCC, in the first phase of our study, we performed targeted RNA sequencing (in HCC and paired non-HCC tissues) on 6 patients with a diagnosis of HCC undergoing liver transplantation.

Results

As a result of these studies, we discovered the novel fusion transcript, VTI1A-CFAP46. In the second phase of our study, we measured the expression of wild-type VTI1A in 21 HCC specimens, which showed that 10 of 21 exhibited upregulation of wild-type VTI1A in their tumors. VTI1A (Vesicle Transport via Interaction with t-SNARE homolog 1A) is a member of the Soluble N-ethylmaleimide-Sensitive Factor (NSF) attachment protein receptor (SNARE) gene family, which is essential for membrane trafficking and function in endocytosis, autophagy, and Golgi transport. Notably, it is known that autophagy is involved in HCC.

Conclusions

The link between novel fusion transcript VTI1A-CFAP46 and autophagy as a potential therapeutic target in HCC patients deserves further investigation. Moreover, this study shows that fusion transcripts are worthy of additional exploration in HCC.

Radwan M, E. Ozturk S, Ulusoy NG, Sozer E, E. Ellakwa D, Ocak Z, Can M, F.S. Ali T, I. Abd-Alla H, Yayli N, Tateishi H, Otsuka M, Fujita M. Design, Synthesis and Biological Evaluation of Pentacyclic Triterpene Derivatives: Optimization of Anti-ABL Kinase Activity

Imatinib, an Abelson (ABL) tyrosine kinase inhibitor, is a lead molecular-targeted drug against chronic myelogenous leukemia (CML). To overcome its resistance and adverse effects, new inhibitors of ABL kinase are needed. Our previous study showed that the benzyl ester of gypsogenin (1c), a pentacyclic triterpene, has anti-ABL kinase and a subsequent anti-CML activity. To optimize its activities, benzyl esters of carefully selected triterpenes (PT1-PT6), from different classes comprising oleanane, ursane and lupane, and new substituted benzyl esters of gypsogenin (GP1-GP5) were synthesized. All of the synthesized compounds were purified and charachterized by different spectroscopic methods. Cytotoxicity of the parent triterpenes and the synthesized compounds against CML cell line K562 was examined; revealing three promising compounds PT5, GP2 and GP5 (IC50 5.46, 4.78 and 3.19 μM, respectively). These compounds were shown to inhibit extracellular signal-regulated kinase (ERK) downstream signaling, and induce apoptosis in K562 cells. Among them, PT5 was identified to have in vitro activity (IC50 = 1.44 μM) against ABL1 kinase, about sixfold of 1c, which was justified by molecular docking. The in vitro activities of GP2 and GP5 are less than PT5, hence they were supposed to possess other more mechanisms of cytotoxicity. In general, our design and derivatizations resulted in enhancing the activity against ABL1 kinase and CML cells.

Prevalence and Clinical Outcome of Philadelphia-Like Acute Lymphoblastic Leukemia: Systematic Review and Meta-analysis

BACKGROUND

The presence of Philadelphia (Ph)-like ALL among patients with acute lymphoblastic leukemia (ALL) may indicate a poor prognosis similar to Ph⁺ ALL, although the data are still inconclusive and the prevalence of Ph-like ALL varied considerably across studies.

PATIENTS AND METHODS

We performed a systematic review and meta-analysis in order to identify all cohort studies of patients with ALL that reported the prevalence of Ph-like ALL and to summarize their results together. The pooled prevalence and rate were calculated by the DerSimonian-Laird random-effect model with double arcsine transformation.

RESULTS

Across the 15 included studies describing 11,040 ALL patients, the peak prevalence of the presence of Ph-like ALL among patients with ALL was between ages 11 and 40 years, where the pooled prevalence was 25.8% to 26.2%. The pooled 5-year overall survival rate of Ph-like ALL was 42.8% (95% confidence interval, 23.9-64.1; I² 93%). Comparative analysis with B-other ALL patients was conducted by the Mantel-Haenszel method; it found that Ph-like ALL patients had a significantly lower chance of being alive at 5 years (pooled odds ratio, 0.35; 95% confidence interval, 0.25-0.50; P < .00001, I² = 40%). The chance of Ph-like ALL patients surviving at 5 years was similar to Ph-positive ALL patients (pooled odds ratio, 0.72; 95% confidence interval, 0.26-2.02; P = .53, I² = 77%).

CONCLUSION

Ph-like ALL is not uncommon among ALL patients, and its presence is associated with an unfavorable outcome. More investigations are needed for better therapeutic options.

Counteracting the effect of leukemia exosomes by antiangiogenic gold nanoparticles

Purpose

Progression of chronic myeloid leukemia (CML) is frequently associated with increased angiogenesis at the bone marrow mediated by exosomes. The capability of gold nanoparticles (AuNPs) functionalized with antiangiogenic peptides to hinder the formation of new blood vessels has been demonstrated in a chorioallantoic membrane (CAM) model.

Methods

Exosomes of K562 CML cell line were isolated and their angiogenic effect assessed in a CAM model. AuNPs functionalized with antiangiogenic peptides were used to block the angiogenic effect of CML-derived exosomes, assessed by evaluation of expression levels of key modulators involved in angiogenic pathways - VEGFA, VEGFR1 (also known as FLT1) and IL8.

Results

Exosomes isolated from K562 cells promoted the doubling of newly formed vessels associated with the increase of VEGFR1 expression. This is a concentration and time-dependent effect. The AuNPs functionalized with antiangiogenic peptides were capable to block the angiogenic effect by modulating VEGFR1 associated pathway.

Conclusion

Exosomes derived from blast cells are capable to trigger (neo)-angiogenesis, a key factor for the progression and spreading of cancer, in particular in CML. AuNPs functionalized with specific antiangiogenic peptides are capable to block the effect of the exosomes produced by malignant cells via modulation of the intrinsic VEGFR pathway. Together, these data highlight the potential of nanomedicine-based strategies against cancer proliferation.

FAM168A participates in the development of chronic myeloid leukemia via BCR-ABL1/AKT1/NFκB pathway

Background

Although the prognosis of chronic myeloid leukemia (CML) has dramatically improved, the pathogenesis of CML remains elusive. Studies have shown that sustained phosphorylation of AKT1 plays a crucial role in the proliferation of CML cells. Evidence indicates that in tongue cancer cells, FAM168A, also known as tongue cancer resistance-associated protein (TCRP1), can directly bind to AKT1 and regulate AKT1/NFκB signaling pathways. This study aimed to investigate the role of FAM168A in regulation of AKT1/NFκB signaling pathway and cell cycle in CML.

Methods

FAM168A interference was performed, and the expression and phosphorylation of FAM168A downstream proteins were measured in K562 CML cell line. The possible roles of FAM168A in the proliferation of CML cells were investigated using in vitro cell culture, in vivo animal models and clinical specimens.

Results

We found that the expression of FAM168A significantly increased in the peripheral blood mononuclear cells of CML patients, compared with normal healthy controls. FAM168A interference did not change AKT1 protein expression, but significantly decreased AKT1 phosphorylation, significantly increased IκB-α protein level, and significantly reduced nuclear NFκB protein level. Moreover, there was a significant increase of G2/M phase cells and Cyclin B1 level. Immunoprecipitation results showed that FAM168A interacts with breakpoint cluster region (BCR) -Abelson murine leukemia (ABL1) fusion protein and AKT1, respectively. Animal experiments confirmed that FAM168A interference prolonged the survival and reduced the tumor formation in mice inoculated with K562 cells. The results of clinical specimens showed that FAM168A expression and AKT1 phosphorylation were significantly elevated in CML patients.

Conclusion

This study demonstrates that FAM168A may act as a linker protein that binds to BCR-ABL1 and AKT1, which further mediates the downstream signaling pathways in CML. Our findings demonstrate that FAM168A may be involved in the regulation of AKT1/NFκB signaling pathway and cell cycle in CML.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5898-4) contains supplementary material, which is available to authorized users.

Frequent homozygous deletions of the CDKN2A locus in somatic cancer tissues

Here we present and describe data on homozygous deletions (HD) of human CDKN2 A and neighboring regions on the p arm of Chromosome 9 from cancer genome sequences deposited on the online Catalogue of Somatic Mutations in Cancer (COSMIC) database. Although CDKN2 A HDs have been previously described in many cancers, this is a pan-cancer report of these aberrations with the aim to map the distribution of the breakpoints. We find that HDs of this locus have a median range of 1,255,650bps. When the deletion breakpoints were mapped on both the telomere and centromere proximal sides of CDKN2A, most of the telomere proximal breakpoints concentrate to a narrow region of the chromosome which includes the gene MTAP.. The centromere proximal breakpoints of the deletions are distributed over a wider chromosomal region. Furthermore, gene expression analysis shows that the deletions that include the CDKN2A region also include the MTAP region and this observation is tissue independent. We propose a model that may explain the origin of the telomere proximal CDKN2A breakpoints Finally, we find that HD distributions for at least three other loci, RB1, SMAD4 and PTEN are also not random.

MXD1 regulates the imatinib resistance of chronic myeloid leukemia cells by repressing BCR-ABL1 expression

Tyrosine kinase inhibitors have achieved unprecedented efficacy in the treatment of chronic myeloid leukemia (CML); however, imatinib resistance has emerged as a major problem in the clinic. Because the overexpression of BCR-ABL1 critically contributes to CML pathogenesis and drug resistance, targeting the regulation of BCR-ABL1 gene expression may be an alternative therapeutic strategy. In this study, we found that the transcriptional repressor MXD1 showed low expression in CML patients and was negatively correlated with BCR-ABL1. Overexpression of MXD1 markedly inhibited the proliferation of K562 cells and sensitized the imatinib-resistant K562/G01 cell line to imatinib, with decreased BCR-ABL1 mRNA and protein expression. Further investigation using reporter gene analysis showed that MXD1 significantly inhibited the transcriptional activity of the BCR-ABL1 gene promoter. Taken together, these data show that MXD1 functions as a negative regulator of BCR-ABL1 expression and subsequently inhibits proliferation and sensitizes CML cells to imatinib treatment.

CircBA9.3 supports the survival of leukaemic cells by up-regulating c-ABL1 or BCR-ABL1 protein levels

The unchecked tyrosine kinase activity of BCR-ABL1 contributes to the immortality of leukaemic cells. Therefore, this oncogene is a highly important therapeutic target for chronic myelogenous leukaemia (CML). Tyrosine kinase inhibitors (TKIs) are an excellent drug treatment for CML patients. However, there are still some patients who are not responsive to TKIs. We found that a novel circular RNA (circRNA), named circBA9.3, is derived from BCR-ABL1. CircBA9.3 can efficiently promote the proliferation and inhibit apoptosis of cancer cells. In addition, some patients with TKI resistance have elevated circBA9.3 expression, which is positively correlated with the level of BCR-ABL1. Furthermore, circBA9.3 is predominantly located in the cytoplasm and enhances c-ABL1 and BCR-ABL1 oncoprotein expression. Thus, circBA9.3 is a molecule associated with increased tyrosine kinase activity that promotes resistance against TKI therapy. In this study, we provided a new potential target for the treatment of TKI-resistant CML patients.