abt-199 and Precursor-Cell-Lymphoblastic-Leukemia-Lymphoma

This article describes a potential treatment for early T-cell precursor acute lymphoblastic leukemia (ETP-ALL), a relatively rare and highly aggressive hematologic malignancy. A 59-year-old woman admitted to our hospital with enlarged cervical lymph nodes, weight loss, abnormal count, and morphology of peripheral blood cells was diagnosed with ETP-ALL according to morphology, immunology, cytogenetics, and molecular biology. The patient initially received two cycles of the VICP regimen, including vincristine, idarubicin, cyclophosphamide, and prednisone, and had a response with positive minimal residual disease (MRD). The patient was then given venetoclax plus the CAG regimen, including aclarubicin, cytosine arabinoside, and granulocyte colony-stimulating factor. After one cycle, the patient achieved complete remission with negative MRD and was eligible for allogeneic hematopoietic stem cell transplantation.

Topics: Aclarubicin; Cytarabine; Female; Granulocyte Colony-Stimulating Factor; Hematopoietic Stem Cell Transplantation; Humans; Middle Aged; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Precursor Cells, T-Lymphoid; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma

Venetoclax, a B-cell lymphoma (BCL-2) inhibitor, in combination with hypomethylating agents has become the new standard of care in elderly and unfit patients with acute myeloid leukemia, with significantly improved overall survival and quality of life. Studies of venetoclax combined with high-dose chemotherapy are emerging with evidence of higher rates of molecular remission. Recently, a growing number of publications bring forth the use of venetoclax in patients with acute lymphoblastic leukemia (ALL). In the current review, we present the biological rationale of BCL-2 inhibition in ALL, how the interplay of BH3 proteins modulate the response and the current clinical experience with various combinations.

Topics: Aged; Antineoplastic Combined Chemotherapy Protocols; Bridged Bicyclo Compounds, Heterocyclic; Humans; Leukemia, Myeloid, Acute; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2; Quality of Life; Sulfonamides

Despite approval of B-cell lymphoma (BCL)-2 inhibitor venetoclax for certain hematologic malignancies, its broader clinical benefit is curtailed by resistance. Our study aimed to determine if treatment with novel anticancer agents targeting BCL-2 and mouse double minute 2 (MDM2) could overcome venetoclax resistance in preclinical models.. Venetoclax-sensitive and venetoclax-resistant acute myeloid leukemia (AML) and acute lymphoblastic leukemia cells and xenograft models were used to evaluate antitumor effects and underlying mechanisms associated with combined BCL-2 inhibitor lisaftoclax (APG-2575) and MDM2 inhibitor alrizomadlin (APG-115).. The combination exhibited synergistic antiproliferative and apoptogenic activities in TP53 wild-type AML cell lines in vitro. This synergy was further exemplified by deep antitumor responses and prolonged survival in AML cell line-derived and patient-derived xenograft models. Interestingly, the combination treatment resensitized (to apoptosis) venetoclax-resistant cellular and mouse models established via chronic drug exposure or genetically engineered with clinically relevant BCL-2 gene mutations. Synergistic effects in reducing cellular viability and proliferation were also demonstrated in primary samples of patients with venetoclax-resistant AML treated with lisaftoclax and alrizomadlin ex vivo. Mechanistically, alrizomadlin likely primes cancer cells to BCL-2 inhibition-induced cellular apoptosis by downregulating expression of antiapoptotic proteins myeloid cell leukemia-1 and BCL-extra-large and upregulating pro-death BCL-2-associated X protein.. Lisaftoclax in combination with alrizomadlin overcomes venetoclax resistance mediated by various mechanisms, including BCL-2 mutations. In addition, we posit further, putative molecular mechanisms. Our data rationalize clinical development of this treatment combination in patients with diseases that are insensitive or resistant to venetoclax.

Topics: Animals; Antineoplastic Agents; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Cell Line, Tumor; Humans; Leukemia, Myeloid, Acute; Mice; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2

Infants with KMT2A-rearranged B-cell acute lymphoblastic leukemia (ALL) have a dismal prognosis. Survival outcomes have remained static in recent decades despite treatment intensification and novel therapies are urgently required. KMT2A-rearranged infant ALL cells are characterized by an abundance of promoter hypermethylation and exhibit high BCL-2 expression, highlighting potential for therapeutic targeting. Here, we show that hypomethylating agents exhibit in vitro additivity when combined with most conventional chemotherapeutic agents. However, in a subset of samples an antagonistic effect was seen between several agents. This was most evident when hypomethylating agents were combined with methotrexate, with upregulation of ATP-binding cassette transporters identified as a potential mechanism. Single agent treatment with azacitidine and decitabine significantly prolonged in vivo survival in KMT2A-rearranged infant ALL xenografts. Treatment of KMT2A-rearranged infant ALL cell lines with azacitidine and decitabine led to differential genome-wide DNA methylation, changes in gene expression and thermal proteome profiling revealed the target protein-binding landscape of these agents. The selective BCL-2 inhibitor, venetoclax, exhibited in vitro additivity in combination with hypomethylating or conventional chemotherapeutic agents. The addition of venetoclax to azacitidine resulted in a significant in vivo survival advantage indicating the therapeutic potential of this combination to improve outcome for infants with KMT2A-rearranged ALL.

Topics: Azacitidine; Decitabine; Humans; Infant; Leukemia, Myeloid, Acute; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Asparaginase; Cell- and Tissue-Based Therapy; Humans; Polyethylene Glycols; Precursor Cell Lymphoblastic Leukemia-Lymphoma

Hypodiploid acute lymphoblastic leukemia (ALL) is an aggressive blood cancer with a poor prognosis despite intensive chemotherapy or stem cell transplant. Children and adolescents with positive end-of-induction minimal residual disease have an overall survival lower than 30%. However, data regarding therapeutic alternatives for this disease is nearly nonexistent, emphasizing the critical need for new or adjunctive therapies that can improve outcomes. We previously reported on the therapeutic efficacy of venetoclax (ABT-199) in hypodiploid B-lineage ALL but with limitations as monotherapy. In this study, we set out to identify drugs enhancing the anti-leukemic effect of venetoclax in hypodiploid ALL. Using a highthroughput drug screen, we identified dinaciclib, a cyclin-dependent kinase inhibitor that worked synergistically with venetoclax to induce cell death in hypodiploid cell lines. This combination eradicated leukemic blasts within hypodiploid ALL patient-derived xenografts mice with low off-target toxicity. Our findings suggest that dual inhibition of BCL-2 (venetoclax) and CDK9/MCL-1 (dinaciclib) is a promising therapeutic approach in hypodiploid ALL, warranting further investigation to inform clinical trials in this high-risk patient population.

Topics: Animals; Antineoplastic Agents; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Cell Line, Tumor; Humans; Mice; Myeloid Cell Leukemia Sequence 1 Protein; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2

Topics: Antibodies, Bispecific; Antineoplastic Agents; Humans; Philadelphia Chromosome; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma; Precursor Cell Lymphoblastic Leukemia-Lymphoma

Early T-cell precursor acute lymphoblastic leukemia (ETP ALL) is a high-risk subgroup of acute lymphoblastic leukemia characterized by unique immune phenotype and disease biology. ETP ALL cells share similarities with hematopoietic stem cells and myeloid progenitor cells. These patients have lower rates of complete remission and overall survival. High BCL2 expression is the main rationale for using venetoclax in ETP ALL.. We report the treatment outcomes of 2 patients with ETP ALL who achieved minimal residual disease negative remission with the short course of venetoclax.. Combination therapy of short-course venetoclax with Berlin-Frankfurt-Meunster 95 regimen is an effective regimen for treating patients with ETP ALL.

Topics: Humans; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Precursor Cells, T-Lymphoid; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma; Treatment Outcome

Outcomes for patients with relapsed and refractory (R/R) T-cell acute lymphoblastic leukemia (T-ALL) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are dismal, with few available treatments. Recently, identification of cancer patients harboring neurotrophic tropomyosin receptor kinase (NTRK) gene fusions is constantly increasing, especially with the advent of NTRK inhibitors. However, the role of ETV6-NTRK3 in T-ALL has not been investigated. This case represented the first detailed report of T-ALL patient harboring a cryptic ETV6-NTRK3 fusion with an unfavorable prognosis, not only because of leukemia resistant to the standard multiagent chemotherapy but also early relapse after allo-HSCT. Acquired EP300 mutation was found at relapse, which could explain the cause of recurrence and affect the follow-up treatment. Combined targeted therapy like larotrectinib allied with pan-targeted BCL-2 inhibitor venetoclax, may be a potential maintenance treatment in R/R ETV6-NTRK3 positive leukemia after allo-HSCT. The leukemic clonal evolution might be revealed through transcriptome sequencing and overcome by drugs with universal targets. Our case demonstrated that both comprehensive profiling techniques (such as transcriptome sequencing, multiparameter flow cytometry, and digital droplet polymerase chain reaction) and a multimodality treatment strategy were critical for anticipating an early relapse and personalized therapy of R/R T-cell leukemia.

Topics: Humans; Oncogene Proteins, Fusion; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma; Recurrence; T-Lymphocytes

Dysregulation of BCL-2 family members has been reported in acute lymphocytic leukemia (ALL), with various BH3-dependencies of the leukemic clone. We conducted a multicenter retrospective cohort of patients with relapsed/refractory B or T ALL, with ven-chemotherapy or ven-navitoclax combinations, to assess efficacy and safety.. Seventeen patients were included in the analysis, median age was 32 years, with 6 B-ALL and 11 T-ALL patients. Nine patients received venetoclax combined with chemotherapy, and 13 patients received venetoclax in combination with navitoclax, vincristine and asparaginase, of which 5 were already exposed to venetoclax in previous lines.. ORR was 55% and 46% among the ven-chemotherapy and the ven-navitoclax-chemotherapy, respectively. Most of the responders proceeded to an allogenic bone marrow transplant in both cohorts. The most common adverse effects of the ven-navitoclax combination were infectious complications and hepatotoxicity.. Our data demonstrated the possible efficacy of ven-chemotherapy and ven-navitoclax in r/r ALL with moderate toxicity.

Topics: Adult; Antineoplastic Combined Chemotherapy Protocols; Humans; Leukemia, Myeloid, Acute; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Retrospective Studies; Salvage Therapy

Topics: Aged; Bridged Bicyclo Compounds, Heterocyclic; Hematopoietic Stem Cell Transplantation; Humans; Philadelphia Chromosome; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prednisone; Remission Induction; Sulfonamides

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Bridged Bicyclo Compounds, Heterocyclic; Female; Humans; Imidazoles; Male; Middle Aged; Mutation; Philadelphia Chromosome; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Pyridazines; Retrospective Studies; Sulfonamides; Young Adult

The prognosis for B-cell precursor acute lymphoblastic leukemia patients with Mixed-Lineage Leukemia (MLL) gene rearrangements (MLLr BCP-ALL) is still extremely poor. Inhibition of anti-apoptotic protein BCL-2 with venetoclax emerged as a promising strategy for this subtype of BCP-ALL, however, lack of sufficient responses in preclinical models and the possibility of developing resistance exclude using venetoclax as monotherapy. Herein, we aimed to uncover potential mechanisms responsible for limited venetoclax activity in MLLr BCP-ALL and to identify drugs that could be used in combination therapy. Using RNA-seq, we observed that long-term exposure to venetoclax in vivo in a patient-derived xenograft model leads to downregulation of several tumor protein 53 (TP53)-related genes. Interestingly, auranofin, a thioredoxin reductase inhibitor, sensitized MLLr BCP-ALL to venetoclax in various in vitro and in vivo models, independently of the p53 pathway functionality. Synergistic activity of these drugs resulted from auranofin-mediated upregulation of NOXA pro-apoptotic protein and potent induction of apoptotic cell death. More specifically, we observed that auranofin orchestrates upregulation of the NOXA-encoding gene Phorbol-12-Myristate-13-Acetate-Induced Protein 1 (PMAIP1) associated with chromatin remodeling and increased transcriptional accessibility. Altogether, these results present an efficacious drug combination that could be considered for the treatment of MLLr BCP-ALL patients, including those with TP53 mutations.

Topics: Apoptosis; Apoptosis Regulatory Proteins; Auranofin; Bridged Bicyclo Compounds, Heterocyclic; Burkitt Lymphoma; Cell Line, Tumor; Humans; Neoplasm Proteins; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Sulfonamides; Tumor Suppressor Protein p53

The clinical data of five cases of relapsed/refractory (R/R) Philadelphia chromosome-positive acute B-lymphocytic leukaemia (Ph. 分析郑州大学附属肿瘤医院采用Bcl-2抑制剂维奈托克联合酪氨酸激酶抑制剂（TKI）及含地塞米松小剂量化疗方案治疗5例复发/难治（R/R）费城染色体阳性急性B淋巴细胞白血病（Ph

Topics: Bridged Bicyclo Compounds, Heterocyclic; Dexamethasone; Humans; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Protein Kinase Inhibitors; Sulfonamides

Topics: Antineoplastic Combined Chemotherapy Protocols; Bridged Bicyclo Compounds, Heterocyclic; Humans; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Remission Induction; Retrospective Studies; Salvage Therapy

The diagnosis of mixed phenotype acute leukemia (MPAL) with T/megakaryocyte or T/myeloid lineages accompanied by t(3;3) is always a challenge. Therefore, multiple experimental methods are usually required to avoid misdiagnosis. In this report, we presented a rare case of MPAL with T/myeloid lineages accompanied by t(3;3) and discussed the experience of differential diagnosis and our appreciation of the MPAL with T/megakaryocyte and T/myeloid lineages accompanied by t(3;3).. A 31-year-old woman was admitted to our hospital due to recurrent fever for 20 days. Two distinct blast populations were detected by flow cytometry analysis: one population fulfills the immunophenotypic criteria for T-lymphoblastic leukemia, while the other population is highly suggestive of megakaryoblasts. These immunophenotypic features support the diagnosis of MPAL (T/megakaryocyte), which is rarely reported​. Interestingly, a complex karyotype was detected afterward by cytogenetics with t(3;3)(q21;q26.2), indicating a diagnosis of AML with t(3;3), a subset of which is also characterized by megakaryocytic markers such as CD41 and CD61. It seems that the second blast population detected by flow cytometry could not be classified into either diagnosis based on the morphology, immunophenotyping, and even cytogenetic findings, posing a real diagnostic problem because of the lack of clear-cut cytogenetic morphological defined criteria to distinguish between acute megakaryocytic leukemia and AML with t(3;3). Combining all of the examination data, this case was ultimately diagnosed as MPAL (T + My)-NOS with t(3;3) through differential diagnosis. Before the cytogenetic results were available, the patient received an acute lymphoblastic leukemia (ALL) regimen for MPAL treatment, but the effect was unsatisfactory. After the diagnosis was clear, she received an AML-like regimen with azacitidine for 7 days and venetoclax for 14 days, and achieved complete morphological remission.. MPAL with either T/megakaryocyte or T/myeloid lineages accompanied by t(3;3) is rare, and it is difficult to make a clear diagnosis. Thus, comprehensive examinations, including bone marrow cell morphology, flow cytometry analysis, cytogenetics, and molecular analysis are recommended to avoid misdiagnosis. AML-like regimen including azacitidine and venetoclax may be effective for treating MPAL (T + My)-NOS with t(3;3).

Topics: Acute Disease; Azacitidine; Bridged Bicyclo Compounds, Heterocyclic; Cell Lineage; Female; Humans; Immunophenotyping; Leukemia, Myeloid, Acute; Megakaryocytes; Phenotype; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Sulfonamides

Topics: Bridged Bicyclo Compounds, Heterocyclic; Casein Kinase II; Humans; Myeloid Cell Leukemia Sequence 1 Protein; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Sulfonamides

Unlike younger adults with acute lymphoblastic leukemia (ALL), older adults are rarely cured due to a combination of intrinsic disease resistance and treatment-related toxicities. Novel therapeutics such as inotuzumab ozogamicin, blinatumomab, venetoclax, and ABL kinase inhibitors have high activity in ALL and are well tolerated by older adults. Frontline treatment regimens for older adults using novel therapeutics with reduction or omission of conventional chemotherapy are being developed with early results demonstrating high remission rates and lower toxicity, but long-term efficacy and toxicity data are lacking. Collaboration between academic and pharmaceutical stakeholders is needed to develop clinical trials to define the optimal treatment regimens for older adults with ALL.

Topics: Aged; Antibodies, Bispecific; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Bridged Bicyclo Compounds, Heterocyclic; Female; Humans; Inotuzumab Ozogamicin; Male; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Protein Kinase Inhibitors; Sulfonamides

Topics: Adult; Aged; Antineoplastic Agents; Bridged Bicyclo Compounds, Heterocyclic; Humans; Imidazoles; Middle Aged; Neoplasm Recurrence, Local; Philadelphia Chromosome; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Pyridazines; Sulfonamides; Survival Analysis; Treatment Outcome

MEF2D-fusion (M-fusion) genes are newly discovered recurrent gene abnormalities that are detected in approximately 5 % of acute lymphoblastic leukemia (ALL) cases. Their introduction to cells has been reported to transform cell lines or increase the colony formation of bone marrow cells, suggesting their survival-supporting ability, which prompted us to examine M-fusion-targeting drugs. To identify compounds that reduce the protein expression level of MEF2D, we developed a high-throughput screening system using 293T cells stably expressing a fusion protein of MEF2D and luciferase, in which the protein expression level of MEF2D was easily measured by a luciferase assay. We screened 3766 compounds with known pharmaceutical activities using this system and selected staurosporine as a potential inducer of the proteolysis of MEF2D. Staurosporine induced the proteolysis of M-fusion proteins in M-fusion (+) ALL cell lines. Proteolysis was inhibited by caspase inhibitors, not proteasome inhibitors, suggesting caspase dependency. Consistent with this result, the growth inhibitory effects of staurosporine were stronger in M-fusion (+) ALL cell lines than in negative cell lines, and caspase inhibitors blocked apoptosis induced by staurosporine. We identified the cleavage site of MEF2D-HNRNPUL1 by caspases and confirmed that its caspase cleavage-resistant mutant was resistant to staurosporine-induced proteolysis. Based on these results, we investigated another Food and Drug Administration-approved caspase activator, venetoclax, and found that it exerted similar effects to staurosporine, namely, the proteolysis of M-fusion proteins and strong growth inhibitory effects in M-fusion (+) ALL cell lines. The present study provides novel insights into drug screening strategies and the clinical indications of venetoclax.

Topics: Antineoplastic Agents; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Caspases; Cell Line, Tumor; Dose-Response Relationship, Drug; Gene Fusion; HEK293 Cells; Humans; MEF2 Transcription Factors; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proteolysis; Signal Transduction; Staurosporine; Sulfonamides

Topics: Adult; Alemtuzumab; Bridged Bicyclo Compounds, Heterocyclic; Epigenesis, Genetic; Humans; Leukemia, Prolymphocytic; Leukemia, Prolymphocytic, T-Cell; Lymphoma; Male; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Sulfonamides; T-Lymphocytes

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Bridged Bicyclo Compounds, Heterocyclic; Drug Synergism; Embryo, Nonmammalian; Humans; Myeloid Cell Leukemia Sequence 1 Protein; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Pyrimidines; Sulfonamides; T-Lymphocytes; Thiophenes; Tumor Cells, Cultured; Zebrafish

B-cell precursor acute lymphoblastic leukemia (BCP-ALL) with TCF3-PBX1 fusion gene expression has constitutively elevated levels of Wnt16b and ROR1 (receptor tyrosine kinase-like orphan receptor), a ligand and a receptor from the Wnt signaling pathway, respectively. Although survival rate is usually high after the initial chemotherapy, many TCF3-PBX1 BCP-ALL patients relapse and subsequently develop treatment resistance, resulting in poor prognosis. Here, we aimed to investigate the molecular signaling associated with Wnt16b and ROR1 overexpression in TCF3-PBX1 cell lines and primary samples, and to identify effective treatment options via ROR1 targeting. We detected higher ROR1 expression on TCF3-PBX1 leukemic cells even at a later stage of patient relapse, providing a strong rationale for the use of ROR1-targeted therapy. We found that Wnt5a-ROR1 signaling enhances proliferation of TCF3-PBX1 cells via RhoA/Rac1 GTPases activation and STAT3 upregulation. Wnt16b also activated the RhoA/Rac1 signaling cascade suggesting the activation of a non-canonical Wnt pathway in TCF3-PBX1 cells. Wnt16 could interact with ROR1 but not in TCF3-PBX1 cells, suggesting that Wnt5a is the ligand signaling via ROR1 in TCF3-PBX1 cells. By high throughput drug-sensitivity testing of TCF3-PBX1 cells before and after ROR1 knockdown we found that targeting ROR1 significantly improves the therapeutic efficacy of Bcl-2 family inhibitors venetoclax and navitoclax, and this synergism was confirmed ex vivo using a drug-resistant primary sample from a relapsed TCF3-PBX1 patient. Our work underlines a new type of targeted combination therapy that could be clinically advantageous for patients with TCF3-PBX1 BCP-ALL.

Topics: Aniline Compounds; Antineoplastic Agents; Bridged Bicyclo Compounds, Heterocyclic; Cell Line, Tumor; Cell Proliferation; Drug Resistance, Neoplasm; Humans; Oncogene Proteins, Fusion; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2; Receptor Tyrosine Kinase-like Orphan Receptors; rhoA GTP-Binding Protein; Sulfonamides; Survival Rate; Translocation, Genetic; Up-Regulation; Wnt Signaling Pathway; Wnt-5a Protein

Deregulated cell death pathways contribute to leukemogenesis and treatment failure in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Intrinsic apoptosis signaling is regulated by different proapoptotic and antiapoptotic molecules: proapoptotic BCL-2 homology domain 3 (BH3) proteins activate prodeath molecules leading to cellular death, while antiapoptotic molecules including B-cell lymphoma 2 (BCL-2) prevent activation of prodeath proteins and counter-regulate apoptosis induction. Inhibition of these antiapoptotic regulators has become a promising strategy for anticancer treatment, but variable anticancer activities in different malignancies indicate the need for upfront identification of responsive patients. Here, we investigated the activity of the BCL-2 inhibitor venetoclax (VEN, ABT-199) in B-cell precursor acute lymphoblastic leukemia and found heterogeneous sensitivities in BCP-ALL cell lines and in a series of patient-derived primografts. To identify parameters of sensitivity and resistance, we evaluated genetic aberrations, gene-expression profiles, expression levels of apoptosis regulators, and functional apoptosis parameters analyzed by mitochondrial profiling using recombinant BH3-like peptides. Importantly, ex vivo VEN sensitivity was most accurately associated with functional BCL-2 dependence detected by BH3 profiling. Modeling clinical application of VEN in a preclinical trial in a set of individual ALL primografts, we identified that leukemia-free survival of VEN treated mice was precisely determined by functional BCL-2 dependence. Moreover, the predictive value of ex vivo measured functional BCL-2 dependence for preclinical in vivo VEN response was confirmed in an independent set of primograft ALL including T- and high risk-ALL. Thus, integrative analysis of the apoptosis signaling indicating mitochondrial addiction to BCL-2 accurately predicts antileukemia activity of VEN, robustly identifies VEN-responsive patients, and provides information for stratification and clinical guidance in future clinical applications of VEN in patients with ALL.

Topics: Animals; Apoptosis; B-Lymphocytes; BH3 Interacting Domain Death Agonist Protein; Bridged Bicyclo Compounds, Heterocyclic; Cell Line, Tumor; Cell Proliferation; Female; Gene Expression Regulation, Leukemic; Heterografts; Humans; Male; Mice; Mitochondria; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2; Signal Transduction; Sulfonamides

Topics: Adult; Antineoplastic Combined Chemotherapy Protocols; Asparaginase; Bridged Bicyclo Compounds, Heterocyclic; Drug Resistance, Neoplasm; Feasibility Studies; Female; Follow-Up Studies; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prognosis; Salvage Therapy; Sulfonamides; Young Adult

The clinical success of the BCL-2-selective BH3-mimetic venetoclax in patients with poor prognosis chronic lymphocytic leukemia (CLL) highlights the potential of targeting the BCL-2-regulated apoptotic pathway in previously untreatable lymphoid malignancies. By selectively inhibiting BCL-2, venetoclax circumvents the dose-limiting, BCL-XL-mediated thrombocytopenia of its less selective predecessor navitoclax, while enhancing efficacy in CLL. We have previously reported the potent sensitivity of many high-risk childhood acute lymphoblastic leukemia (ALL) xenografts to navitoclax. Given the superior tolerability of venetoclax, here we have investigated its efficacy in childhood ALL. We demonstrate that in contrast to the clear dependence of CLL on BCL-2 alone, effective antileukemic activity in the majority of ALL xenografts requires concurrent inhibition of both BCL-2 and BCL-XL We identify BCL-XL expression as a key predictor of poor response to venetoclax and demonstrate that concurrent inhibition of both BCL-2 and BCL-XL results in synergistic killing in the majority of ALL xenografts. A notable exception is mixed lineage leukemia-rearranged infant ALL, where venetoclax largely recapitulates the activity of navitoclax, identifying this subgroup of patients as potential candidates for clinical trials of venetoclax in childhood ALL. Conversely, our findings provide a clear basis for progressing navitoclax into trials ahead of venetoclax in other subgroups.

Topics: Animals; Antineoplastic Agents; Apoptosis; Blotting, Western; Bridged Bicyclo Compounds, Heterocyclic; Cell Proliferation; Child; Drug Resistance, Neoplasm; Female; Flow Cytometry; Gene Rearrangement; Histone-Lysine N-Methyltransferase; Humans; Mice; Mice, Inbred NOD; Mice, SCID; Myeloid-Lymphoid Leukemia Protein; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sulfonamides; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+)ALL) remains a challenge. Although the addition of targeted tyrosine kinase inhibitors (TKIs) to standard cytotoxic therapy has greatly improved upfront treatment, treatment-related morbidity and mortality remain high. TKI monotherapy provides only temporary responses and renders patients susceptible to the development of TKI resistance. Thus, identifying agents that could enhance the activity of TKIs is urgently needed. Recently, a selective inhibitor of B cell lymphoma 2 (BCL-2), ABT-199 (venetoclax), has shown impressive activity against hematologic malignancies. We demonstrate that the combination of TKIs with venetoclax is highly synergistic in vitro, decreasing cell viability and inducing apoptosis in Ph(+)ALL. Furthermore, the multikinase inhibitors dasatinib and ponatinib appear to have the added advantage of inducing Lck/Yes novel tyrosine kinase (LYN)-mediated proapoptotic BCL-2-like protein 11 (BIM) expression and inhibiting up-regulation of antiapoptotic myeloid cell leukemia 1 (MCL-1), thereby potentially overcoming the development of venetoclax resistance. Evaluation of the dasatinib-venetoclax combination for the treatment of primary Ph(+)ALL patient samples in xenografted immunodeficient mice confirmed the tolerability of this drug combination and demonstrated its superior antileukemic efficacy compared to either agent alone. These data suggest that the combination of dasatinib and venetoclax has the potential to improve the treatment of Ph(+)ALL and should be further evaluated for patient care.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Bridged Bicyclo Compounds, Heterocyclic; Cell Line, Tumor; Dasatinib; Humans; Imidazoles; Mice; Mice, Inbred NOD; Mice, Knockout; Mice, SCID; Myeloid Cell Leukemia Sequence 1 Protein; Philadelphia Chromosome; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-abl; Proto-Oncogene Proteins c-bcl-2; Pyridazines; src-Family Kinases; STAT5 Transcription Factor; Sulfonamides; Translational Research, Biomedical; Xenograft Model Antitumor Assays

BH3 mimetic drugs may be useful to treat acute lymphoblastic leukemia (ALL) but the sensitivity of primary tumor cells has not been fully evaluated. Here, B-lineage ALL cell cultures derived from a set of primary tumors were studied with respect to sensitivity to the BH3 mimetics ABT-263 and ABT-199 and to Bcl-2 dependence and function. These ALL cells each expressed high levels of Bcl-2 and exhibited great sensitivity to ABT-263 and ABT-199, which induced rapid apoptotic cell death. BH3 profiling indicated that the ALL cultures were Bcl-2 dependent. Coimmunoprecipitation studies revealed a multifaceted role for Bcl-2 in binding proapoptotic partners including Bax, Bak, Bik, and Bim. ABT-263 disrupted Bcl-2:Bim interaction in cells. Mcl-1 overexpression rendered ALL cells resistant to ABT-263 and ABT-199, with Mcl-1 assuming the role of Bcl-2 in binding Bim. Freshly isolated pediatric ALL blasts also expressed high levels of Bcl-2 and exhibited high sensitivity to Bcl-2 inhibition by the BH3 mimetic compounds. Overall, our results showed that primary ALL cultures were both more sensitive to BH3 mimetics and more uniform in their response than established ALL cell lines that have been evaluated previously. Furthermore, the primary cell model characterized here offers a powerful system for preclinical testing of novel drugs and drug combinations to treat ALL.

Topics: Aniline Compounds; Antineoplastic Agents; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Cell Survival; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; HeLa Cells; Humans; Inhibitory Concentration 50; Myeloid Cell Leukemia Sequence 1 Protein; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-bcl-2; Sulfonamides