[Efficacy of venetoclax-based induction regimen in newly diagnosed pediatric acute myeloid leukemia].

Objective: To explore the efficacy of venetoclax-based induction regimen for children with newly diagnosed acute myeloid leukemia (AML). Methods: Children with newly diagnosed AML in Beijing Children's Hospital Affiliated to Capital Medical University and Baoding Hospital Affliliated to Capital Medical University from November 2019 and December 2023 were prospectively included. The patients were divided into DAH group (daunorubicin, cytarabine and homoharringtonine) and VAH group (venetoclax, cytarabine and homoharringtonine) according to induction regimen. The clinical data of the children were collected, the clinical characteristics and induced remission rate between the two groups were compared, and multivariate logistic regression was used to analyze the related factors affecting the induced remission rate. Results: A total of 135 patients were enrolled, including 96 cases in the DAH group (54 males and 42 females), aged [M (Q1, Q3)] 6.4 (3.9, 11.6) years and 39 cases in the VAH group (26 males and 13 females), aged 8.0 (6.2, 13.2) years. Among patients initially diagnosed with low-medium risk AML, the morphologic complete remission rates were 94.7% (18/19) in the VAH group and 84.4% (38/45) in the DAH group, respectively, and the negativity conversion rates of minirnal residual disease (MRD) were 57.9% (11/19) and 46.7% (21/45), respectively, with no statistically difference (all P>0.05). Among patients initially diagnoised with high-risk AML, the morphologic complete remission rates in the VAH group was higher than that in the DAH group [95.0% (19/20) vs 70.6% (36/51), P=0.027], and negativity conversion rates of MRD were 45.0% (9/20) and 33.3% (17/51), respectively, with no statistically difference (P=0.359). The induction regimen (venetoclax, cytarabine and homoharringtonin) was beneficial to morphological remission (OR=0.126, 95%CI: 0.025-0.629). FLT3 mutation was not conducive to morphological remission (OR=5.832, 95%CI: 1.778-19.124) and negative MRD (OR=4.166, 95%CI: 1.396-12.433). Conclusion: Venetoclax-based induction regimen is more effective than traditional chemotherapy regimen for newly diagnosed pediatric AML.

Homoharringtonine is synergistically lethal with BCL-2 inhibitor APG-2575 in acute myeloid leukemia.

BACKGROUND: Despite advances in targeted agent development, effective treatment of acute myeloid leukemia (AML) remains a major clinical challenge. The B-cell lymphoma-2 (BCL-2) inhibitor exhibited promising clinical activity in AML, acute lymphoblastic leukemia (ALL) and diffuse large B-cell lymphoma (DLBCL) treatment. APG-2575 is a novel BCL-2 selective inhibitor, which has demonstrated anti-tumor activity in hematologic malignancies. Homoharringtonine (HHT), an alkaloid, exhibited anti-AML activity. METHODS: The synergistic effects of APG-2575 and HHT were studied in AML cell lines and primary samples. MTS was used to measure the cell viability. Annexin V/propidium iodide staining was used to measure the apoptosis rate by flow cytometry. AML cell xenografted mouse models were established to evaluate the anti-leukemic effect of BCL-2 inhibitor, HHT and their combination in vivo. Western blot was used to determine the expression of related proteins. RESULTS: APG-2575 showed comparable anti-leukemic effect to the FDA-approved BCL-2 inhibitor ABT-199 in vitro and in vivo. Combined treatment of HHT with APG-2575 synergistically inhibited AML cell growth and engraftment. Mechanistically, HHT promoted degradation of myeloid cell leukemia-1 (MCL-1), which was reported to induce BCL-2 inhibitor resistant, through the PI3K/AKT/GSK3ß signaling pathway. CONCLUSION: Our results provide an effective AML treatment strategy through combination of APG-2575 and HHT, which is worthy of further clinical research.

Sorafenib and omacetaxine mepesuccinate as a safe and effective treatment for acute myeloid leukemia carrying internal tandem duplication of Fms-like tyrosine kinase 3.

BACKGROUND: Omacetaxine mepesuccinate (OME) has antileukemic effects against acute myeloid leukemia (AML) carrying an internal tandem duplication of Fms-like tyrosine kinase 3 (FLT3-ITD). A phase 2 clinical trial was conducted to evaluate a combination treatment of sorafenib and omacetaxine mepesuccinate (SOME). METHODS: Relapsed or refractory (R/R) or newly diagnosed patients were treated with sorafenib (200-400 mg twice daily) and OME (2 mg daily) for 7 (first course) or 5 days (second course onward) every 21 days until disease progression or allogeneic hematopoietic stem cell transplantation (HSCT). The primary endpoint was composite complete remission, which was defined as complete remission (CR) plus complete remission with incomplete hematologic recovery (CRi). Secondary endpoints were leukemia-free survival (LFS) and overall survival (OS). RESULTS: Thirty-nine R/R patients and 5 newly diagnosed patients were recruited. Among the R/R patients, 28 achieved CR or CRi. Two patients showed partial remission, and 9 patients did not respond. Among the 5 newly diagnosed patients, 4 achieved CR, and 1 achieved CRi. The median LFS and OS were 5.6 and 10.9 months, respectively. Prior Fms-like tyrosine kinase 3 (FLT3) inhibitor exposure (P = .007), 2 or more inductions (P = .001), and coexisting IDH2 (P = .008) and RUNX1 mutations (P = .003) were associated with lower CR/CRi rates. HSCT consolidation and deep molecular responses (defined as an FLT3-ITD variant allelic frequency [VAF] ≤ 0.1% or a nucleophosmin 1 [NPM1] mutant VAF ≤ 0.01%) were associated with better OS and LFS. Prior FLT3 inhibitor exposure and 2 or more inductions were associated with inferior LFS. CONCLUSIONS: SOME was safe and effective for R/R and newly diagnosed FLT3-ITD AML.

Homoharringtonine may help improve the outcomes of venetoclax and azacitidine in AML1-ETO positive acute myeloid leukemia.

PURPOSE: T(8;21)(q22;q22.1)/AML1-ETO positive acute myeloid leukemia (AE-AML) is sensitive to conventional chemotherapy with a favorable prognosis. However, recent small case reports suggest the limited effectiveness of venetoclax (VEN) and hypomethylating agents (HMA) in treating AE-AML. The aim of this retrospective study was to evaluate the effectiveness of VEN plus AZA (VA) in AE-AML and explore whether adding homoharringtonine (HHT) to VA (VAH) could improve the response. METHODS: Patients who received VEN plus AZA and HHT (VAH) or VEN plus AZA (VA) regimens were included in this retrospective study. The endpoints of this study were to evaluate the rate of composite complete remission (CRc), measurable residual disease (MRD), event-free survival (EFS), overall survival (OS), and relapse between VAH and VA groups. RESULTS: A total of 32 AE-AML patients who underwent VA or VAH treatments (newly diagnosed with VA, ND-VA, n = 8; relapsed/refractory with VA, R/R-VA, n = 10; relapsed/refractory with VAH, R/R-VAH, n = 14) were included. The CR (complete remission) /CRi (CR with incomplete count recovery) rate of ND-VA, R/R-VA and R/R-VAH were 25%, 10%, and 64.3%, respectively. Measurable residual disease (MRD) negative was observed in 66.7% of R/R-VAH and none of VA-R/R patients. Co-occurring methylation mutations are associated with poor outcomes with VA but exhibit a more favorable response with VAH treatment. Additionally, patients with c-kit mutation presented inferior outcomes with both VEN-based regimens. All regimens were tolerated well by all patients. CONCLUSION: Our data confirmed the poor response of VA in AE-AML, whether used as frontline or salvage therapy. Adding HHT to VA may improve outcomes and enhance the efficacy of VEN in this population.

Low dose of homoharringtonine and cytarabine-based priming induction regimens for patients with de novo acute myeloid leukemia and high-risk myelodysplastic syndrome aged over 70 years.

OBJECTIVES: Our objective is to retrospectively analyze the response to low dose of homoharringtonine (HHT) and cytarabine-based priming induction regimens in patients above 70 years with de novo acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS). PATIENTS AND METHODS: We retrospectively analyzed these very elderly newly diagnosed patients with AML and high-risk MDS, who received low dose of HHT and cytarabine-based priming induction regimens between March 2006 and September 2019. RESULTS: Of the 24 patients, 11 patients (47.8%) achieved complete remission (CR) and 3 (13%) partial remission, and the overall response rate was 60.9%. The estimated median overall survival (OS) time was 12 months and the 1-year OS rate was 47.8%. Patients without CR and Charlson's Comorbidity Index > 2 may be the two independent prognostic factors. The median OS was significantly higher for patients with CR after induction chemotherapy than those without CR (22.93 vs. 8.5 months, p < .01). CONCLUSION: Our study provides a hint of the efficacy of low dose of HHT and cytarabine-based priming induction regimens for patients aged over 70 years with de novo AML and high-risk MDS should be further studied.

Homoharringtonine synergizes with quizartinib in FLT3-ITD acute myeloid leukemia by targeting FLT3-AKT-c-Myc pathway.

Acute myeloid leukemia (AML) with FLT3 internal tandem duplication (FLT3-ITD) has a dismal prognosis. FLT3 inhibitors have been developed to treat patients with FLT3-ITD AML; however, when used alone, their efficacy is insufficient. FLT3 inhibitors combined with chemotherapy may be a promising treatment for FLT3-ITD AML. Homoharringtonine (HHT) is a classical anti-leukaemia drug with high sensitivity to FLT3-ITD AML cells. Here, we showed that HHT synergizes with a selective next-generation FLT3 inhibitor, quizartinib, to inhibit cell growth/viability and induce cell-cycle arrest and apoptosis in FLT3-ITD AML cells in vitro, significantly inhibit acute myeloid leukemia progression in vivo, and substantially prolong survival of mice-bearing human FLT3-ITD AML. Mechanistically, HHT and quizartinib cooperatively inhibit FLT3-AKT and its downstream targets GSK3ß, c-Myc, and cyclin D1, cooperatively up-regulate the pro-apoptosis proteins Bim and Bax, and down-regulate the anti-apoptosis protein Mcl1. Most strikingly, HHT and quizartinib cooperatively reduce the numbers of side-population (SP) and aldehyde dehydrogenase (ALDH)-positive cells, which reportedly are rich in LSCs. In conclusion, HHT combined with quizartinib may be a promising treatment strategy for patients with FLT3-ITD AML.

Acute pancreatitis induced by combination chemotherapy used for the treatment of acute myeloid leukemia: A case report.

RATIONALE: Drug-induced pancreatitis (DIP) is a kind of acute pancreatitis with a relatively low incidence. There are many cases of acute pancreatitis (AP) caused by chemotherapeutic agents that have been reported. However, few reports focus on the combination of chemotherapeutic agents that induce acute pancreatitis. This article aims to retrospectively analyze a case of DIP and to explore the relationship between chemotherapeutic agents and acute pancreatitis. PATIENT CONCERNS: Here, we report a 35-year-old Chinese female patient who was diagnosed as acute myeloid leukemia with BCR/ABL expression. After induction chemotherapy of daunorubicin and cytarabine, bone marrow aspiration showed: Acute myeloid leukemia-not relieved (AML-NR). Then the regimen of homoharringtonine, cytarabine and dasatinib was started. The patient developed abdominal pain on the 14th day of chemotherapy. Laboratory tests showed elevated serum amylase (AMY) and lipase (LIPA). Computed tomography (CT) of the abdomen revealed a swollen pancreas with blurred edges and thickened left prerenal fascia. DIAGNOSIS: The patient was diagnosed as DIP by the symptoms of upper abdominal pain and the change of CT images. Other common causes of AP were excluded meanwhile. INTERVENTIONS: The chemotherapy was stopped immediately. And after fasting, fluid infusion and inhibiting the secretion of the pancreas, the symptoms were relieved. OUTCOMES: DIP relapsed when the regimen of aclacinomycin + cytarabine + G-CSF + dasatinib regimen (G-CSF (400ug/day, day 1 to 15), cytarabine (30 mg/day, day 2 to 15), aclacinomycin (20 mg/day, day 2 to 5)and dasatinib (140 mg/day, continuously)) was given, and was recovered after treatment for AP was performed. LESSONS: To choose the best treatment plan for patients, clinicians should raise awareness of DIP, and should know that chemotherapeutic agents can induce pancreatitis and the combination of chemotherapeutic agents may increase the risk of drug-induced pancreatitis.

Venetoclax + hypomethylating agents combined with dose-adjusted HAG for relapsed/refractory acute myeloid leukemia: Two case reports.

RATIONALE: Some acute myeloid leukemia (AML) patients are unresponsive to treatment or have remission followed by worsening of disease (known as relapsed/refractory AML [R/RAML]) after standardized treatment. The CAG/HAG regimen is not often used clinically because heterogenous patient responses, resistance, and hematopoietic bone marrow dysfunction have been reported with its use. We present 2 cases of R/RAML treated with a new combined therapy (venetoclax+ hypomethylating agents [HMAs]) in which the HAG dose was adjusted and effective in the first course of treatment. PATIENT CHARACTERISTICS: Case 1 involved a 23-year-old man who had suffered from AML for >4 years, and his FLT3 mutation status was positive at the initial diagnosis. After the first course of treatment with the standard-dose "Da" plan, the patient experienced complete remission. During the subsequent courses of treatment, the patient experienced 6 recurrences and was treated with the "ID Ara-C + MIT + sidaaniline" and "CAG + sidaaniline" regimens. However, the disease did not respond. Case 2 involved a 26-year-old man who received chemotherapy with the "Da," "ID Ara-C," "decitabine + half-dose CAG," and "HAE" regimens. In this patients, remission could not be achieved. Reintroduction of the "ia" scheme also failed after treatment in our hospital. DIAGNOSIS: Two patients were diagnosed with R/RAML. INTERVENTIONS: The patient in case 2 received chemotherapy interventions, whereas the patient in case 1 refused to receive medical services at our hospital. OUTCOMES: The patient in case 1 was discharged after complete response treatment due to economic reasons and relapsed 2 months later. The patient ultimately died of infection and heart failure. The patient in case 2 is receiving a second cycle of chemotherapy. LESSONS: We recommend the "venetoclax + HMAs combined with dose-adjusted CAH/HAG" regimen as an effective treatment for adult R/RAML.

Comparison of efficacy of HCAG and FLAG re-induction chemotherapy in acute myeloid leukemia patients of low- and intermediate-risk groups.

PURPOSE: The aim of the present study was to investigate the efficacy and adverse effects of HCAG and FLAG re-induction chemotherapy in acute myeloid leukemia (AML) patients of low- and intermediate-risk groups following induction failure. METHODS: A total of 98 AML patients were enrolled. Among these subjects, 47 patients were treated with HCAG chemotherapy, while 51 patients were treated with FLAG chemotherapy. RESULT: The complete remission (CR) and overall remission (OFF) were 24% and 38%, respectively in patients with HCAG induction chemotherapy, while the corresponding percentages were 28% and 42% in subject receiving FLAG chemotherapy. The median survival time of progress-free survival (PFS) was 29.8 (95% CI 23.749-35.851) months in the HCAG group and 30.8 (95% CI 21.728-39.872) months in the FLAG group (P = 0.620). A total of 42 patients in the HCAG group suffered from grade 4 hematological toxicity, while this adverse reaction was noted for all patients who were treated with FLAG chemotherapy (P = 0.023). A total of 19 cases indicated apparent nonhematological toxicity in the HCAG group, while only 40 (78.4%) were noted with these adverse reactions in the FLAG group (P = 0.000). CONCLUSION: The HCAG regimen exhibited a similar effect compared with the FLAG regimen in low- and intermediate-risk groups, although the HCAG regimen significantly decreased the toxicity compared with that noted in the FLAG regimen group.

Minimal residual disease may be an early prognostic indicator for newly diagnosed acute myeloid leukemia patients induced by decitabine-based chemotherapy.

Objectives: To analyze the efficacy and safety of decitabine combined with low/reduced-dose chemotherapy in newly diagnosed acute myeloid leukemia (AML) patients unfit for intensive therapy and to investigate the early prognostic indicators for these patients. Methods: The eligible patients treated with decitabine-based chemotherapy were retrospectively analyzed. Responses and long-term survival were calculated and their correlation with clinical characteristics was analyzed. Minimal residual disease (MRD) detected by flow cytometry (FCM) after the induction therapy was measured, and the association with prognosis was explored. Results: Fifty-five newly diagnosed AML patients were enrolled. The overall response rate (ORR) was 80.0%, with a complete remission (CR) rate of 63.64% and partial remission (PR) rate of 16.36%. Grade 4 hematological toxicity was common, and the incidence of infections was 83.64%, with 18.18% of patients suffered from severe infections. No serious bleeding or non-hematological adverse events occurred. Treatment-related mortality was 3.64%. The median overall survival (OS) and disease-free survival (DFS) were 17.0 (13.7-20.3) months and 17.0 (10.2-23.8) months, respectively. Multivariate analysis showed that an advanced age (≥ 60 years) and higher MRD (≥ 1.34%) after induction therapy were adverse prognostic factors for patients who had achieved CR. Conclusions: Decitabine-based chemotherapy may be a suitable therapeutic alternative for newly diagnosed AML patients who are unfit for intensive chemotherapy. An advanced age (≥ 60 years) and higher MRD (≥ 1.34%) were considered adverse prognostic factors.

Acute myeloid leukemia in an 86-year-old man with AML1/ETO treated with Homoharringtonine and Arsenic Trioxide: A case report.

RATIONALE: Acute myeloid leukemia (AML) is a malignantly clonal and highly heterogeneous disease. Although the treatment of AML has brought promising outcomes for younger patients, prognosis of the elderly remains dismal. Innovative regimens are increasingly necessary to be investigated. PATIENT CONCERNS: We present an 86-year-old AML patient with fever, cough, and sputum production. DIAGNOSES: A diagnosis of AML with maturation (AML-M2) and AML1/ETO was made. INTERVENTIONS: The patient was treated with a regimen of Homoharringtonine coupled with arsenic trioxide. OUTCOMES: The AML-M2 patient with AML1/ETO achieved incomplete remission, but showed few toxic side effects and improved survival. Besides, we analyzed the dynamic counts of complete blood cells during the treatment. The count of white blood cell had a positive correlation with the percentage of blast cells (r = 0.65), both of which had a negative correlation with the percentage of segmented neutrophils (r = -0.63, -0.89). LESSONS: Homoharringtonine and arsenic trioxide may induce both the apoptosis and differentiation of leukemic cells in AML-M2 with AML1/ETO.

Abivertinib, a novel BTK inhibitor: Anti-Leukemia effects and synergistic efficacy with homoharringtonine in acute myeloid leukemia.

Ibrutinib, an inhibitor of Bruton tyrosine kinase (BTK), has shown promising pharmacologic effects in acute myeloid leukemia (AML). In this study, we report that abivertinib or AC0010, a novel BTK inhibitor, inhibits cell proliferation, reduces colony-forming capacity, and induces apoptosis and cell cycle arrest in AML cells, especially those harboring FLT3-ITD mutations. Abivertinib was also found to be more sensitive than ibrutinib in treating AML. We demonstrate that in addition to targeting the phosphorylation of BTK, abivertinib also targeted the crucial PI3K survival pathway. Furthermore, abivertinib suppressed the expression of p-FLT3 and the downstream target p-STAT5 in AML cells harboring FLT3-ITD mutations. Moreover, in vitro and in vivo data revealed synergistic activity between abivertinib and homoharringtonine (HHT), a natural plant alkaloid commonly used in China, in treating AML cells with or without FLT3-ITD mutations. Collectively, these preclinical data suggest that abivertinib may be a promising novel agent for AML, with potential for combination treatment with HHT. Clinical studies on abivertinib-involved therapy are planned.

Synergistic killing effects of homoharringtonine and arsenic trioxide on acute myeloid leukemia stem cells and the underlying mechanisms.

BACKGROUND: At present, it is generally believed that leukemia stem cells are the source of AML, so the killing of leukemia stem cells has become important. Previous studies have suggested that HHT combined with ATO can synergistically kill U937 cells, and HHT has also demonstrated the ability to kill leukemia stem cells. We evaluated whether HHT combined with ATO can systematically kill leukemia stem cells (LSCs) and explored the synergistic effect and molecular mechanism. METHODS: CCK-8 was used to detect cell viability. The changes of cell cycle (PI staining), apoptosis (Annexin V/PI) and surface markers (CD34, CD38, CD96, CD45) were detected by flow cytometry. The cells of CD34+ primary leukemia and CD38- KG-1, and TF-1 were separated by flow cytometry. High-throughput mRNA sequencing was used to analysis mRNA level changes after the application of the two drugs. Western blot was used to verify the changes of pathway protein expression. NRG mice were used as the receptor of xenograft model. Histological H&E staining assess the invaded ability of leukemia cells, and laser scanning confocal microscopy evaluated the molecule markers change. RESULTS: HHT and ATO synergistically killed KG-1 (CD34+/CD96+/CD38+/-) and Kasumi-1 (CD34+/CD38-) cells. Their combination had a stronger effect of inducing apoptosis and blocking the cell cycle than HHT or ATO administrator alone, meanwhile significantly reducing the numbers of LSCs. Further, CD34+CD38- cells in KG-1, KG-1a, TF-1, and primary leukemia cells were more sensitive to HHT and ATO. High-throughput mRNA sequencing suggested that HHT alone could significantly upregulate molecules related to the Notch, P53, and NF-κB signaling pathways. When combined with ATO, HHT further upregulated P53, whereas HHT-induced NF-κB pathway activation was significantly suppressed. Western blot analysis verified the change of protein expression in the above pathways and further demonstrated that GSI, could eliminate these effects. In vivo, HHT combined with ATO significantly reduced the LSC burden, and weakened the expression of LSC markers. CONCLUSIONS: This is the first evidence that HHT combined with arsenic can synergistically kill LSCs in vitro and in vivo, along with identification of the underlying mechanism, highlighting a potentially effective treatment strategy.

Hydroxycoumarin OT-55 kills CML cells alone or in synergy with imatinib or Synribo: Involvement of ER stress and DAMP release.

We synthetized and investigated the anti-leukemic potential of the novel cytostatic bis(4-hydroxycoumarin) derivative OT-55 which complied with the Lipinski's rule of 5 and induced differential toxicity in various chronic myeloid leukemia (CML) cell models. OT-55 triggered ER stress leading to canonical, caspase-dependent apoptosis and release of danger associated molecular patterns. Consequently, OT-55 promoted phagocytosis of OT-55-treated CML cells by both murine and human monocyte-derived macrophages. Moreover, OT-55 inhibited tumor necrosis factor α-induced activation of nuclear factor-кB and produced synergistic effects when used in combination with imatinib to inhibit colony formation in vitro and Bcr-Abl+ patient blast xenograft growth in zebrafish. Furthermore, OT-55 synergized with omacetaxine in imatinib-resistant KBM-5 R cells to inhibit the expression of Mcl-1, triggering apoptosis. In imatinib-resistant K562 R cells, OT-55 triggered necrosis and blocked tumor formation in zebrafish in combination with omacetaxine.