Managing Philadelphia chromosome-positive acute lymphoblastic leukemia: role of tyrosine kinase inhibitors

Integrated systems biology analysis of acute lymphoblastic leukemia: unveiling molecular signatures and drug repurposing opportunities

Acute lymphoblastic leukemia (ALL) is a hematological malignancy characterized by aberrant proliferation and accumulation of lymphoid precursor cells within the bone marrow. The tyrosine kinase inhibitor (TKI), imatinib mesylate, has played a significant role in the treatment of Philadelphia chromosome-positive ALL (Ph + ALL). However, the achievement of durable and sustained therapeutic success remains a challenge due to the development of TKI resistance during the clinical course.The primary objective of this investigation is to propose a novel and efficacious treatment approach through drug repositioning, targeting ALL and its Ph + subtype by identifying and addressing differentially expressed genes (DEGs). This study involves a comprehensive analysis of transcriptome datasets pertaining to ALL and Ph + ALL in order to identify DEGs associated with the progression of these diseases to identify possible repurposable drugs that target identified hub proteins.The outcomes of this research have unveiled 698 disease-related DEGs for ALL and 100 for Ph + ALL. Furthermore, a subset of drugs, specifically glipizide for Ph + ALL, and maytansine and isoprenaline for ALL, have been identified as potential candidates for therapeutic intervention. Subsequently, cytotoxicity assessments were performed to confirm the in vitro cytotoxic effects of these selected drugs on both ALL and Ph + ALL cell lines.In conclusion, this study offers a promising avenue for the management of ALL and Ph + ALL through drug repurposed drugs. Further investigations are necessary to elucidate the mechanisms underlying cell death, and clinical trials are recommended to validate the promising results obtained through drug repositioning strategies.

Comparison of autologous and allogeneic stem cell transplantation for patients with Philadelphia chromosome-positive acute lymphoblastic leukemia

Objectives: To analyze the outcomes of patients who received autologous stem cell transplantation (auto-SCT), matched sibling donor stem cell transplantation (MSD-SCT) and haploidentical stem cell transplantation (haplo-SCT) and provide the basis for the choice of transplantation method in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Methods: We retrospectively investigated the outcomes of 119 adult patients with Ph+ ALL in our center. The overall survival (OS) rate, leukemia-free survival (LFS) rate, cumulative incidence of relapse (CIR) rate, non-relapse mortality (NRM) rate and the impact of achievement of complete molecular response (CMR) within 3 months and sustaining CMR up to transplantation (s3CMR) on transplantation method were explored. Results: The estimated OS, LFS, CIR and NRM rates at 3 years were not significantly different among three groups (p = 0.960, 0.917, 0.375 and 0.096, respectively). For the 65 patients who achieved s3CMR, there was no significant difference in OS (84.5% vs 72.5% vs 100%, p = 0.374), LFS (75.2% vs 64.5% vs 83.3%, p = 0.668), CIR (17.2% vs 8.1% vs 16.7%, p = 0.583) and NRM (3.1% vs 23.4% vs 0%, p = 0.055) among auto-SCT group, MSD-SCT group and haplo-SCT group. However, in patients who did not achieve s3CMR, auto-SCT recipients tended to have higher CIR (60% vs 33.2% vs 24.0%, p = 0.013) than the allo-HSCT group. Conclusions: Auto-SCT with maintenance therapy after HSCT appears to be an attractive treatment option for patients with Ph+ ALL especially for those whose s3CMR was kept up to transplantation. For non-s3CMR patients, allogeneic transplantation may be more effective from lower relapse.

[Comparison of autologous versus matched sibling donor stem cell transplantation for patients with Philadelphia chromosome-positive acute lymphoblastic leukemia]

目的

比较自体造血干细胞移植（auto-HSCT）和同胞全相合造血干细胞移植（MSD-HSCT）治疗费城染色体阳性急性淋巴细胞白血病（Ph⁺ ALL）的疗效，为患者移植方式的选择提供依据。

方法

回顾性总结2008年1月至2017年12月于中国医学科学院血液病医院行auto-HSCT（31例）及MSD-HSCT（47例）的78例Ph⁺ ALL患者的临床特征，比较不同移植方式患者的总生存（OS）率、无白血病生存（LFS）率、累积复发率（CIR）及非复发死亡率（NRM），并观察是否3个月内实现完全分子学缓解并持续至移植（s3CMR）条件下不同移植方式对预后的影响。

结果

auto-HSCT组、MSD-HSCT组粒细胞植入的中位时间分别为12（10～29）d、14（11～24）d（P＝0.006），血小板植入的中位时间分别为17.5（10～62）d、17（10～33）d（P＝0.794）。MSD-HSCT组中，Ⅱ～Ⅳ度和Ⅲ～Ⅳ度急性移植物抗宿主病（GVHD）的发生率分别为27.7%（13/47）和8.5%（4/47），局限型和广泛型慢性GVHD的发生率为17.0%（8/47）和12.8%（6/47）。auto-HSCT组、MSD-HSCT组3年CIR、NRM、LFS率差异均无统计学意义（P值均>0.05）。在达到s3CMR的44例患者中，auto-HSCT组和MSD-HSCT组的3年OS率［（84.0±8.6）%对（78.0±8.7）%，P＝0.612］、LFS率［（70.3±10.3）%对（68.2±10.1）%，P＝0.970］、CIR［（24.9±10.0）%对（14.4±8.0）%，P＝0.286］和NRM［（4.7±4.7）%对（17.4±8.1）%，P＝0.209］差异均无统计学意义；未达到s3CMR的34例患者中，auto-HSCT组与MSD-HSCT组相比，3年CIR明显升高［（80.0±14.7）%对（39.6±10.9）%，P＝0.057］。

结论

对于化疗后达s3CMR的Ph⁺ ALL患者，auto-HSCT是一种有效的巩固治疗选择，与MSD-HSCT疗效相当；对于未达到s3CMR的患者，MSD-HSCT复发率更低。

Ponatinib for Treating Acute Lymphoblastic Leukaemia: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

As part of its single technology appraisal (STA) process, the UK National Institute for Health and Care Excellence (NICE) invited the manufacturer (Incyte Corporation) of ponatinib (Inclusig^®) to submit evidence of its clinical and cost effectiveness for previously treated Philadelphia-chromosome-positive acute lymphoblastic leukaemia (Ph+ ALL) and chronic myeloid leukaemia. This paper focusses on Ph+ ALL. The School of Health and Related Research Technology Appraisal Group at the University of Sheffield was commissioned to act as the independent evidence review group (ERG). This article presents the critical review of the company's submission by the ERG and the outcome of the NICE guidance. The clinical-effectiveness evidence in the company's submission was derived from a phase II, single-arm, open-label, non-comparative study. Given the lack of comparative evidence, a naïve indirect comparison was performed against re-induction chemotherapy comparing major cytogenetic response and complete remission. Best supportive care (BSC) was assumed to produce no disease response. Despite the limited evidence and potential for biases, this study demonstrated that ponatinib was likely to be an effective treatment for patients with Ph+ ALL. The company submitted a state transition model that analysed the incremental cost effectiveness of ponatinib versus re-induction therapy and BSC for the treatment of Ph+ ALL in patients whose disease is resistant to dasatinib, who are intolerant to dasatinib and for whom subsequent treatment with imatinib is not clinically appropriate or who have the threonine-315-isoleucine mutation. This population was further subdivided into those who were suitable for allogeneic stem cell transplant (allo-SCT) and those who were not. The company's revised economic evaluation, following the clarification process, estimated incremental cost-effectiveness ratios (ICERs) in those suitable for allo-SCT of £31,123 per quality-adjusted life-year (QALY) gained for ponatinib compared with re-induction chemotherapy and £26,624 per QALY gained compared with BSC. For those for whom allo-SCT was unsuitable, the company-estimated ICER compared with BSC was £33,954 per QALY gained. Following a critique of the model, the ERG undertook exploratory analyses that, when combined, produced a range in ICERs (due to uncertainty of the most appropriate overall survival function) of dominant (being less expensive and providing more QALYs) to £11,727 per QALY gained compared with re-induction chemotherapy and between £7892 and £31,696 per QALY gained compared with BSC for those in whom allo-SCT was suitable. For those in whom allo-SCT was not suitable, the ERG estimated that ponatinib was dominant. During the consultation period, the company agreed a revised patient access scheme (PAS) that reduced the ICER ranges to £7156 to £29,995 per QALY gained versus BSC and to less than £5000 per QALY gained versus re-induction chemotherapy. In people for whom allo-SCT was unsuitable, ponatinib dominated BSC. The NICE appraisal committee concluded that ponatinib is a cost-effective use of UK NHS resources in the considered population, subject to the company providing the agreed discount in the PAS.

Chronic Myeloid Leukemia--Prognostic Value of Mutations

Chronic myeloid leukemia (CML) is a stem cell disorder characterized by unrestricted proliferation of the myeloid series that occurs due to the BCR-ABL fusion oncogene as a result of reciprocal translocation t(9;22) (q34;q11). This discovery has made this particular domain a target for future efforts to cure CML. Imatinib revolutionized the treatment options for CML and gave encouraging results both in case of safety as well as tolerability profile as compared to agents such as hydroxyurea or busulfan given before Imatinib. However, about 2-4% of patients show resistance and mutations have been found to be one of the reasons for its development. European Leukemianet gives recommendations for BCR-ABL mutational analysis along with other tyrosine kinase inhibitors (TKIs) that should be administered according to the mutations harbored in a patient. The following overview gives recommendations for monitoring patients on the basis of their mutational status.

Selective Inhibition of Human Equilibrative and Concentrative Nucleoside Transporters by BCR-ABL Kinase Inhibitors: IDENTIFICATION OF KEY hENT1 AMINO ACID RESIDUES FOR INTERACTION WITH BCR-ABL KINASE INHIBITORS

Human nucleoside transporters (hNTs) mediate cellular influx of anticancer nucleoside drugs, including cytarabine, cladribine, and fludarabine. BCR-ABL tyrosine kinase inhibitors (TKIs) imatinib and dasatinib inhibit fludarabine and cytarabine uptake. We assessed interactions of bosutinib, dasatinib, imatinib, nilotinib, and ponatinib with recombinant hNTs (hENT1, 2; hCNT1, -2, and -3) produced individually in yeast Saccharomyces cerevisiae Nilotinib inhibited hENT1-mediated uridine transport most potently (IC50 value, 0.7 μm) followed by ponatinib > bosutinib > dasatinib > imatinib. Imatinib inhibited hCNT2 with an IC50 value of 2.3 μm Ponatinib inhibited all five hNTs with the greatest effect seen for hENT1 (IC50 value, 9 μm). TKIs inhibited [(3)H]uridine uptake in a competitive manner. Studies in yeast with mutants at two amino acid residues of hENT1 (L442I, L442T, M33A, M33A/L442I) previously shown to be involved in uridine and dipyridamole binding, suggested that BCR-ABL TKIs interacted with Met(33) (TM1) and Leu(442) (TM11) residues of hENT1. In cultured human CEM lymphoblastoid cells, which possess a single hNT type (hENT1), accumulation of [(3)H]cytarabine, [(3)H]cladribine, or [(3)H]fludarabine was reduced by each of the five TKIs, and also caused a reduction in cell surface expression of hENT1 protein. In conclusion, BCR-ABL TKIs variously inhibit five different hNTs, cause a decrease in cell surface hENT1 expression, and decrease uridine accumulation when presented together with uridine or when given before uridine. In experiments with mutant hENT1, we showed for the first time interaction of Met(33) (involved in dipyridamole binding) with BCR-ABL inhibitors and reduced interaction with M33A mutant hENT1.

A Case of Dasatinib-Induced Hemorrhagic Colitis Diagnosed by the Lymphocyte Transformation Test in a Chronic Myeloid Leukemia Patient

Dasatinib is an effective treatment option for patients diagnosed with Philadelphia chromosome positive chronic myeloid leukemia and who are non-responsive or intolerant to imatinib treatment. Dasatinib, however, is associated with various adverse effects and on rare occasions, may cause hemorrhagic colitis. We report the case of a 68-year-old male patient with dasatinib-induced hemorrhagic colitis, the first such case in Korea. Endoscopic biopsy of the transverse colon demonstrated non-specific inflammatory changes only. Cessation of dasatinib led to the resolution of symptoms, while reintroduction of the therapy led to the recurrence of his bloody diarrhea. To clarify the association between dasatinib and hemorrhagic colitis, the lymphocyte transformation test (LTT) was performed. The LTT result sustained a relatively high proliferation activity in the affected patient compared with almost no proliferation activity in normal control.

Anti-leukemic activity of axitinib against cells harboring the BCR-ABL T315I point mutation

The BCR-ABL; breakpoint cluster region-Abelson point mutation T315I is resistant to ABL tyrosine kinase inhibitors. However, axitinib, a vascular endothelial growth factor receptor inhibitor, is effective against this mutation. In this study, we investigated axitinib activity against ponatinib-resistant cells and found that axitinib inhibited cellular growth and apoptosis in Ba/F3 T315I-mutant cells and T315I-mutant primary samples, but not in ponatinib-resistant Ba/F3 cells and primary samples. Thus, an alternative strategy may be required to improve the prognosis of Philadelphia-chromosome-positive leukemia patients harboring BCR-ABL point mutations.

Acute leukemia

Although great progress has been made in the understanding and treatment of acute leukemia, this disease has not been conquered. For emergency providers (EPs), the presentation of these patients to an emergency department presents a host of challenges. A patient may present with a new diagnosis of leukemia or with complications of the disease process or associated chemotherapy. It is incumbent on EPs to be familiar with the manifestations of leukemia in its various stages and maintain some suspicion for this diagnosis, given the nebulous and insidious manner in which leukemia can present.

Management of imatinib-resistant patients with chronic myeloid leukemia

Since its approval in 2001 for frontline management of chronic myelogenous leukemia (CML), imatinib has proven to be very effective in achieving high remission rates and improving prognosis. However, up to 33% of patients will not achieve optimal response. This has led researchers to develop new second- and third-generation tyrosine kinase inhibitors. In this article, we review the mechanisms of resistance, recommendations for monitoring, assessment of milestones, and management options for patients with CML who are resistant to imatinib therapy. We further explain the potential pitfalls that can lead to unnecessary discontinuation, the prognosis of patients whose condition fails to respond to treatment, and the upcoming therapies.

Persistent complete molecular remission after nilotinib and graft-versus-leukemia effect in an acute lymphoblastic leukemia patient with cytogenetic relapse after allogeneic stem cell transplantation

We report the successful treatment and sustained molecular remission using single agent nilotinib in a relapsed Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia patient after allogeneic hematopoietic stem cell transplantation. Compared to previously published studies, this is the first report where a patient did not receive additional chemotherapy after relapse, nor did she receive donor lymphocyte infusions. With nilotinib, the patient reverted back to normal blood counts and 100% donor reconstitution by single tandem repeat (STR) chimerism analysis in the bone marrow and in peripheral blood, granulocytes, T and B-lymphocytes. This report also highlights the use of nilotinib in combination with extracorporeal photopheresis (ECP) for concomitant graft-versus-host disease. Our data suggests that ECP, together with nilotinib, did not adversely affect the overall Graft-versus-leukemia (GVL) effect.

Tyrosine kinase inhibitors in acute and chronic leukemias

INTRODUCTION

Since the initial approval of imatinib much has been learned about its resistance mechanisms, and efforts have continued to improve upon BCR-ABL tyrosine kinase inhibitor therapy. Targeted therapy with TKIs has continued to be an area of active research and development in the care of acute and chronic leukemia patients.

AREAS COVERED

This article reviews current approved and investigational TKI treatments for chronic myelogenous leukemia (CML), Philadelphia-chromosome positive acute lymphoblastic leukemia (Ph + ALL) and acute myelogenous leukemia (AML).

EXPERT OPINION

There are now more potent BCR-ABL TKIs approved, which allow for additional options when determining front-line and second-line CML and Ph + ALL treatments. The T315I mutation is an ever-present challenge. Ponatinib, a pan BCR-ABL TKI, while still under investigation, is very hopeful with its ability to overcome T315I mutations in resistant CML and Ph + ALL patients. Because nilotinib and dasatinib have not been directly compared, at present we recommend selecting one or the other based on the side-effect profile, drug interactions, patient comorbidities, and mutational status. FLT-3 inhibition is of particular interest in AML patients with FLT-3 internal tandem duplication mutations; this type of targeted therapy continues to be studied.