[Efficacy and safety of gilteritinib-based combination therapy bridging allo-HSCT in relapsed or refractory acute myeloid leukemia patients with positive FLT3-ITD mutation].

Objective: This study aims to evaluate the safety and effectiveness of gilteritinib (Gilt) -based combination therapy bridging allo-HSCT for FLT3-ITD(+) R/R AML. Additionally, it aims to assess the impact of Gilt maintenance therapy on the prognosis of patients after allo-HSCT. Methods: The clinical data of 26 patients with FLT3-ITD(+) R/R AML treated at the First Affiliated Hospital of Soochow University from August 2019 to January 2023 were retrospectively analyzed. The analysis included an assessment of the composite complete remission rate (CRc), overall survival (OS) time, disease-free survival (DFS) time, and adverse events experienced by all enrolled patients. Results: A total of 26 patients with FLT3-ITD(+) R/R AML were enrolled, including 14 men and 12 women with a median age of 38 (18-65) years. A total of 18 cases were refractory, and eight cases were relapsed. The curative effect evaluation conducted between 14 and 21 days showed that the complete remission (CR) rate was 26.9% (7/26), the CR with hematology incomplete recovery was 57.7% (15/26), and the partial response (PR) rate was 7.7% (2/26). The CRc was 84.6% (22/26), and the minimal residual disease (MRD) negativity rate was 65.4%. The 12 month cumulative OS rate for all patients was 79.0%, and the 24 month cumulative OS rate was 72.0%. The median OS time was not determined. The median follow-up time was 16.0 months. Among the patients who responded to treatment, the 12 month cumulative DFS rate was 78.0%, and the 24 month cumulative DFS rate was 71.0%. The median DFS time was not determined. Patients who received allo-HSCT had a median OS time that was significantly longer than those who did not receive allo-HSCT (3.3 months, 95%CI 2.2-4.3 months, P=0.005). The median OS time of patients with or without Gilt maintenance therapy after allo-HSCT was not determined, but the OS time of patients with Gilt maintenance therapy after allo-HSCT treatment was longer than that of patients without Gilt maintenance therapy after allo-HSCT treatment (P=0.019). The FLT3-ITD mutation clearance rate in this study was 38.5%, and the median OS time of patients with FLT3-ITD mutation clearance was not determined but was significantly longer than the median OS of patients without FLT3-ITD mutation clearance (15.0 months; P=0.018). The most common grade 3 and above hematological adverse events of Gilt-based combination therapy included leukopenia (76.9%), neutropenia (76.9%), febrile neutropenia (61.5%), thrombocytopenia (69.2%), and anemia (57.7%). One patient developed differentiation syndrome during oral Gilt maintenance therapy after allo-HSCT treatment, but his condition improved after treatment. Conclusion: The Gilt-based combination therapy is highly effective in treating FLT3-ITD(+) R/R AML. It demonstrates a high CRc, MRD negativity rate, and rapid onset, leading to a significant improvement in patients' survival. Furthermore, the clearance rate of FLT3-ITD mutation is notably high. Additionally, implementing bridging allo-HSCT and Gilt maintenance therapy after allo-HSCT treatment has considerably enhances patients' survival. Closely monitoring and managing any adverse event that may occur during treatment are crucial.

[Preparation of a dual-specific antibody targeting human CD123 and exploration of its anti-acute myeloid leukemia effects].

Objective: To construct a novel dual-specific antibody targeting human CD123 (CD123 DuAb) and study its effects in acute myeloid leukemia (AML) . Methods: Based on the variable region of the CD123 monoclonal antibody independently developed at our institution, the CD123 DuAb expression plasmid was constructed by molecular cloning and transfected into ExpiCHO-S cells to prepare the antibody protein. Through a series of in vitro experiments, its activation and proliferation effect on T cells, as well as the effect of promoting T-cell killing of AML cells, were verified. Results: ① A novel CD123 DuAb plasmid targeting CD123 was successfully constructed and expressed in the Expi-CHO eukaryotic system. ②The CD123 DuAb could bind both CD3 on T cells and CD123 on CD123(+) tumor cells. ③When T cells were co-cultured with MV4-11 cells with addition of the CD123 DuAb at a concentration of 1 nmol/L, the positive expression rates of CD69 and CD25 on T cells were 68.0% and 44.3%, respectively, which were significantly higher than those of the control group (P<0.05). ④Co-culture with CD123 DuAb at 1 nmol/L promoted T-cell proliferation, and the absolute T-cell count increased from 5×10(5)/ml to 3.2×10(6)/ml on day 9, and CFSE fluorescence intensity decreased significantly. ⑤ With the increase in CD123 DuAb concentration in the culture system, T-cell exhaustion and apoptosis increased. When the CD123 DuAb was added at a concentration of 1 nmol/L to the culture system, the proportion of CD8(+) PD-1(+) LAG-3(+) T cells was 10.90%, and the proportion of propidium iodide (PI) (-) Annexin Ⅴ(+) T cells and PI(+) Annexin Ⅴ(+) T cells was 18.27% and 11.43%, respectively, which were significantly higher than those in the control group (P<0.05). ⑥ The CD123 DuAb significantly activated T cells, and the activation intensity was positively correlated with its concentration. The expression rate of CD107a on T cells reached 16.05% with 1 nmol/L CD123 DuAb, which was significantly higher than that of the control group (P<0.05). ⑦The CD123 DuAb promoted cytokine secretion by T cells at a concentration of 1 nmol/L, and the concentration of IFN-γ and TNF-α in the supernatant of the co-culture system reached 193.8 pg/ml and 169.8 pg/ml, respectively, which was significantly higher than that of the control group (P<0.05). ⑧When CD123 DuAb was added at a concentration of 1 nmol/L to the co-culture system of T cells and CD123(+) tumor cells, the killing intensity of T cells significantly increased, and the residual rates of CD123(+) MV4-11 cells, CD123(+) Molm13 cells, and CD123(+) THP-1 cells were 7.4%, 6.7%, and 14.6% on day 3, respectively, which were significantly lower than those in the control group (P<0.05) . Conclusion: In this study, a novel CD123 DuAb was constructed and expressed. In vitro experiments verified that the DuAb binds to CD123(+) tumor cells and T cells simultaneously, promotes T-cell activation and proliferation, and facilitates their anti-leukemia effect, which provides a basis for further clinical research.

[Efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation in the treatment of secondary acute myeloid leukemia].

Objective: To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with secondary acute myeloid leukemia (sAML) . Methods: In this multicenter, retrospective clinical study, adult patients aged ≥18 years who underwent allo-HSCT for sAML at four centers of the Zhejiang Hematopoietic Stem Cell Transplantation Collaborative Group from January 2014 to November 2022 were included, and the efficacy and prognostic factors of allo-HSCT were analyzed. Results: A total of 95 patients were enrolled; 66 (69.5%) had myelodysplastic syndrome-acute myeloid leukemia (MDS-AML) , 4 (4.2%) had MDS/MPN-AML, and 25 (26.3%) had therapy-related AML (tAML) . The 3-year CIR, LFS, and overall survival (OS) rates were 18.6% (95% CI 10.2%-27.0%) , 70.6% (95% CI 60.8%-80.4%) , and 73.3% (95% CI 63.9%-82.7%) , respectively. The 3-year CIRs of the M-AML group (including MDS-AML and MDS/MPN-AML) and the tAML group were 20.0% and 16.4%, respectively (P=0.430) . The 3-year LFSs were 68.3% and 75.4%, respectively (P=0.176) . The 3-year OS rates were 69.7% and 75.4%, respectively (P=0.233) . The 3-year CIRs of the groups with and without TP53 mutations were 60.0% and 13.7%, respectively (P=0.003) ; the 3-year LFSs were 20.0% and 76.5%, respectively (P=0.002) ; and the 3-year OS rates were 40.0% and 77.6%, respectively (P=0.002) . According to European LeukmiaNet 2022 (ELN2022) risk stratification, the 3-year CIRs of patients in the low-, intermediate-, and high-risk groups were 8.3%, 17.8%, and 22.6%, respectively (P=0.639) . The three-year LFSs were 91.7%, 69.5%, and 65.6%, respectively (P=0.268) . The 3-year OS rates were 91.7%, 71.4%, and 70.1%, respectively (P=0.314) . Multivariate analysis revealed that advanced disease at allo-HSCT and TP53 mutations were independent risk factors for CIR, LFS, and OS. Conclusion: There was no significant difference in the prognosis of patients who underwent allo-HSCT among the MDS-AML, MDS/MPN-AML, and tAML groups. Advanced disease at transplantation and TP53 mutations were poor prognostic factors. ELN2022 risk stratification had limited value for predicting the prognosis of patients with sAML following allo-HSCT.

Feasibility, accuracy, and usability analysis of MapAML, a first-in-class app for integrated diagnosis in acute myeloid leukemia.

Performing a comprehensive diagnosis of acute myeloid leukemia (AML) is complex and involves the integration of clinical information, bone marrow morphology, immunophenotyping, cytogenetic, and molecular analysis, which can be challenging to the general hematologist. The aim of this study was to evaluate the usability and accuracy of MapAML, a smartphone app for integrated diagnosis in AML, created to aid the hematologist in its clinical practice. App performance was evaluated in dedicated sessions, in which 21 hematologists or fellows in hematology performed an integrated diagnosis of deidentified real-world clinical AML cases, first without and posteriorly with MapAML use. Diagnosis accuracy increased after MapAML utilization, with the average score going from 7.08 without app to 8.88 with app use (on a scale from 0 to 10), representing a significant accuracy improvement (p = .002). Usability evaluation was very favorable, with 81% of users considering the app very or extremely simple to use. There was also a significant increase in confidence to perform a complete and accurate diagnosis in AML after app use, with 61.9% of the participants willing to use the app in their clinical practice. In this study, MapAML increased accuracy with excellent usability for integrated diagnosis in AML.

[Effect of clonal hematopoiesis in remission on hematopoiesis recovery in patients with NPM1 mutated acute myeloid leukemia after chemotherapy].

Objective: To investigate the effect of clonal hematopoiesis (CH) in remission on hematopoiesis recovery in patients with NPM1 mutated acute myeloid leukemia (AML) after chemotherapy. Methods: Retrospective analysis was performed on 86 patients with NPM1(mut) AML newly diagnosed and treated in the First Affiliated Hospital of Soochow University between July 2016 and June 2019. Their clinical data and NGS test results at diagnosis were analyzed. Moreover, bone marrow samples in remission were tested using Sanger sequencing. The log-rank test was used to analyze the difference in hematopoietic recovery, and Cox proportional hazard models were used to analyze the prognostic factors affecting hematopoietic recovery. Results: The median age of the 86 NPM1(mut) AML patients was 50 years (15-69 years). There were 39 males and 47 females. Forty-one patients were induced with intensity chemotherapy ("7 + 3"), whereas 45 patients were treated with low-dose cytarabine-based induction chemotherapy. At diagnosis, The most common mutations in the patients were FLT3, DNMT3A, TET2, and IDH1/IDH2 mutations. CH-associated mutations persisted in 21 patients during remission, and the mutations were DNMT3A, TET2, ASXL1, and IDH1/IDH2. The recovery time of neutrophils in patients with CH-associated mutations in remission was consistent with that in patients without CH in remission (P=0.282) but the recovery time of platelets in patients with CH in remission was significantly longer[26 (95% CI 21-32) days vs 25 (95% CI 23-26) days, P=0.032]. Furthermore, univariate analysis indicated that age, induced chemotherapy program, and CH in remission were risk factors for platelet recovery, whereas multivariate analysis indicated that induced chemotherapy program and CH in remission were independent risk factors for platelet recovery (HR=0.454, P=0.001 and HR=0.520, P=0.027, respectively) . Conclusion: CH in remission delays the hematopoietic recovery of patients with NPM1(mut) AML after chemotherapy.

Acute abdominal pain due to atypical bilateral adrenal infarction in acute myeloid leukemia with alterations related to myelodysplasia: A case report.

Key Clinical Message: Acute myeloid leukemia (AML) can cause acute abdomen following adrenal insufficiency or adrenal infarction. Therefore, when diffusely enlarged adrenal glands and adrenal insufficiency of unknown cause are seen in a patient presenting with acute abdomen, adrenal infarction due to AML, or other hematologic diseases should be ruled out. Abstract: A 49-year-old man developed acute abdominal pain following adrenal insufficiency and was diagnosed with acute myeloid leukemia (AML) with myelodysplasia-related changes. Because AML can cause acute abdominal pain due to adrenal infarction following adrenal insufficiency, a patient with these conditions should be ruled out adrenal infarction due to AML or other hematologic diseases.

[Establishment of leukemia cell model with inducible AML1-ETO expression and its effect on fatty acid metabolism in leukemia cells].

Objective: To investigate the effect of the AML1-ETO (AE) fusion gene on the biological function of U937 leukemia cells by establishing a leukemia cell model that induces AE fusion gene expression. Methods: The doxycycline (Dox) -dependent expression of the AE fusion gene in the U937 cell line (U937-AE) were established using a lentivirus vector system. The Cell Counting Kit 8 methods, including the PI and sidanilide induction, were used to detect cell proliferation, cell cycle-induced differentiation assays, respectively. The effect of the AE fusion gene on the biological function of U937-AE cells was preliminarily explored using transcriptome sequencing and metabonomic sequencing. Results: ①The Dox-dependent Tet-on regulatory system was successfully constructed to regulate the stable AE fusion gene expression in U937-AE cells. ②Cell proliferation slowed down and the cell proliferation rate with AE expression (3.47±0.07) was lower than AE non-expression (3.86 ± 0.05) after inducing the AE fusion gene expression for 24 h (P<0.05). The proportion of cells in the G(0)/G(1) phase in the cell cycle increased, with AE expression [ (63.45±3.10) %) ] was higher than AE non-expression [ (41.36± 9.56) %] (P<0.05). The proportion of cells expressing CD13 and CD14 decreased with the expression of AE. The AE negative group is significantly higher than the AE positive group (P<0.05). ③The enrichment analysis of the transcriptome sequencing gene set revealed significantly enriched quiescence, nuclear factor kappa-light-chain-enhancer of activated B cells, interferon-α/γ, and other inflammatory response and immune regulation signals after AE expression. ④Disorder of fatty acid metabolism of U937-AE cells occurred under the influence of AE. The concentration of the medium and short-chain fatty acid acylcarnitine metabolites decreased in cells with AE expressing, propionyl L-carnitine, wherein those with AE expression (0.46±0.13) were lower than those with AE non-expression (1.00±0.27) (P<0.05). The metabolite concentration of some long-chain fatty acid acylcarnitine increased in cells with AE expressing tetradecanoyl carnitine, wherein those with AE expression (1.26±0.01) were higher than those with AE non-expression (1.00±0.05) (P<0.05) . Conclusion: This study successfully established a leukemia cell model that can induce AE expression. The AE expression blocked the cell cycle and inhibited cell differentiation. The gene sets related to the inflammatory reactions was significantly enriched in U937-AE cells that express AE, and fatty acid metabolism was disordered.

[Clinical study of induction chemotherapy followed by allogeneic hematopoietic stem cell transplantation in the treatment of FLT3-ITD(+) acute myeloid leukemia with normal karyotype].

Objective: To assess the efficacy of induction chemotherapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of FLT3-ITD(+) acute myeloid leukemia (AML) with normal karyotype. Methods: The clinical data of FLT3-ITD(+) AML patients with normal karyotype in the First Affiliated Hospital of Nanjing Medical University from Jan 2018 to March 2021 were retrospectively analyzed. Results: The study included 49 patients with FLT3-ITD(+)AML, 31 males, and 18 females, with a median age of 46 (16-59) years old. All patients received induction chemotherapy, and 24 patients received sequential allo-HSCT (transplantation group) . The median follow-up time was 465 days, the one-year overall survival (OS) from diagnosis was (70.0 ± 7.4) %, and one-year disease-free survival (DFS) was (70.3±7.4) %. The one-year OS was significantly different between the transplantation group and the non-transplantation group [ (85.2 ± 7.9) % vs (52.6 ± 12.3) %, P=0.049]. but one-year DFS [ (84.7 ± 8.1) % vs (55.2 ± 11.9) %, P=0.061] was not. No significance was found in one-year OS between patients with low-frequency and high-frequency FLT3-ITD(+) (P>0.05) . There were 12 patients with high-frequency FLT3-ITD(+) in the transplantation and the non-transplantation groups, respectively. The one-year OS [ (68.8 ± 15.7) % in the transplantation group vs (26.2 ± 15.3) % in the non-transplantation group, P=0.027] and one-year DFS [ (45.5 ± 21.3) % in the transplantation group vs (27.8±15.8) % in the non-transplantation group, P=0.032] were significantly different between the two groups. Conclusion: Induction chemotherapy followed by allo-HSCT can enhance the prognosis of FLT3-ITD(+) patients, particularly those with FLT3-ITD high-frequency mutation.

Relapsed Acute Myeloid Leukemia Presenting as Multiple Breast Masses: A Case Report.

Hematologic malignancy of the breast is very rare. Here, we report a case of relapsed acute myeloid leukemia (AML) presenting as multiple breast masses. A 77-year-old female visited an outpatient clinic reporting palpable masses in both breasts. She had a medical history of AML, which showed complete remission after nine cycles of chemotherapy. On mammography and ultrasonography, there were multiple masses correlated with her palpable symptoms accompanied by enlarged lymph nodes. Core needle biopsy immunohistochemistry (IHC) results indicated AML and blastic plasmacytoid dendritic cell neoplasm. AML was confirmed using bone marrow biopsy. Although very rare, when a patient with a history of hematologic malignancy presents a palpable mass in the breast, clinicians should conduct proper tissue analysis, including IHC stating for leukemic markers, to guide appropriate diagnosis and treatment.

Pediatric chronic myeloid leukemia in myeloid blast crisis.

Chronic myeloid leukemia (CML) accounts for 2-3% of childhood leukemias. About 5% of cases present in a blastic phase of CML which clinically and morphologically mimics more common acute leukemias of childhood. We report a case of a 3-year-old male who presented with gradual onset swelling of the abdomen and extremities along with generalized weakness. Examination revealed massive splenomegaly, pallor, and pedal edema. Initial workup showed anemia, thrombocytopenia, and leukocytosis (120,000/uL) with a blast percentage of 35%. Blasts were positive for CD13, CD33, CD117, CD34 and HLA-DR, and stained negative for Myeloperoxidase and Periodic Acid Schiff. Fluorescence in situ hybridization was positive for b3a2/e14a2 junction BCR-ABL1 transcript and negative for RUNX1-RUNX1T1/t(8;21), clinching the diagnosis of CML in myeloid blast crisis. The patient expired within 17 days of diagnosis and initiation of therapy.

[Treatment responses, outcomes, and prognostic factors associated with them in patients with secondary acute myeloid leukemia].

Objective: To evaluate treatment responses, outcomes, and prognostic factors in adults with secondary acute myeloid leukemia (sAML) . Methods: Between January 2008 and February 2021, date of consecutive cases of younger than 65 years of adults with sAML were assessed retrospectively. Clinical characteristics at diagnosis, treatment responses, recurrence, and survival were evaluated. Logistic regression and Cox proportional hazards model were employed to determine significant prognostic indicators for treatment response and survival. Results: 155 patients were recruited, including 38, 46, 57, 14 patients belonging to t-AML, and AML with unexplained cytopenia, post-MDS-AML, and post-MPN-AML, respectively. In the 152 evaluable patients, the rate of MLFS after the initial induction regimen was 47.4%, 57.9%, 54.3%, 40.0%, and 23.1% in the four groups (P=0.076) . The total rate of MLFS after the induction regimen was 63.8%, 73.3%, 69.6%, 58.2%, and 38.5% (P=0.084) , respectively. Multivariate analysis demonstrated that male gender (OR=0.4, 95% CI 0.2-0.9, P=0.038 and OR=0.3, 95% CI 0.1-0.8, P=0.015) , SWOG cytogenetic classification into unfavorable or intermediate (OR=0.1, 95% CI 0.1-0.6, P=0.014 and OR=0.1, 95% CI 0.1-0.3, P=0.004) and receiving low-intensity regimen as induction regimen (OR=0.1, 95% CI 0.1-0.3, P=0.003 and OR=0.1, 95%CI 0.1-0.2, P=0.001) were typical adverse factors impacting the first CR and the final CR; PLT<45 × 10(9)/L (OR=0.4, 95%CI 0.2-0.9, P=0.038) and LDH ≥258 U/L (OR=0.3, 95%CI 0.1-0.7, P=0.005) were independent factors for CR. Among the 94 patients with achieving MLFS, 46 cases had allogeneic hematopoietic stem cell transplantation. With a median follow-up period of 18.6 months, the probabilities of relapse-free survival (RFS) and overall survival (OS) at 3 years were 25.4% and 37.3% in patients with transplantation, and in patients with chemotherapy, the probabilities of RFS and OS at 3-year were 58.2% and 64.3%, respectively. At the time of achieving MLFS, multivariate analysis revealed that age ≥46 years (HR=3.4, 95%CI 1.6-7.2, P=0.002 and HR=2.5, 95%CI 1.1-6.0, P=0.037) , peripheral blasts ≥17.5% at diagnosis (HR=2.5, 95%CI 1.2-4.9, P=0.010 and HR=4.1, 95%CI 1.7-9.7, P=0.002) , monosomal karyotypes (HR=4.9, 95%CI 1.2-19.9, P=0.027 and HR=28.3, 95%CI 4.2-189.5, P=0.001) were typical adverse factors influencing RFS and OS. Furthermore, CR after induction chemotherapy (HR=0.4, 95%CI 0.2-0.8, P=0.015) and transplantation (HR=0.4, 95%CI 0.2-0.9, P=0.028) were substantially linked to longer RFS. Conclusion: Post-MDS-AML and post-MPN-AML had lower response rates and poorer prognoses than t-AML and AML with unexplained cytopenia. In adults with male gender, low platelet count, high LDH, and SWOG cytogenetic classification into unfavorable or intermediate at diagnosis, and receiving low-intensity regimen as the induction regimen predicted a low response rate. Age ≥46 years, a higher proportion of peripheral blasts and monosomal karyotype had a negative effect on the overall outcome. Transplantation and CR after induction chemotherapy were greatly linked to longer RFS.

[Venetoclax: A New Hope for Elderly Patients with Acute Myeloid Leukemia]. / Venetoclax: Uma Nova Esperança para o Doente Idoso com Leucemia Mielóide Aguda.

Acute myeloid leukemia (AML) is a hematopoietic malignancy characterized by clonal proliferation, with increased incidence with advancing age. AML with myelodysplasia-related changes (AML-MRC) represents an AML subtype with a poor prognosis and challenging treatment, particularly in elderly patients. We report the case of a 77-year-old patient diagnosed with high-risk AML-MRC, ineligible for intensive chemotherapy, with frequent need of transfusion of red cell concentrates. The authors present, to the best of their knowledge, the first patient in Portugal with AML-MRC treated with an hypomethylating agent, azacytidine, and a BCL2 inhibitor (venetoclax), and that association was essential in the treatment and overall survival, which was much higher than expected.

A leucemia mielóide aguda (LMA) é uma neoplasia hematológica caracterizada pela proliferação clonal, com incidência crescente com a idade. A LMA com alterações relacionadas com mielodisplasia (LMA-ARM) representa um subtipo de LMA com prognóstico adverso, cujo tratamento é desafiante, sobretudo nos doentes mais idosos. Descrevemos o caso de uma doente de 77 anos com o diagnóstico de LMA-ARM, de alto risco inelegível para quimioterapia intensiva, com necessidades transfusionais frequentes. Tanto quanto é do seu conhecimento, os autores apresentam o primeiro caso clínico de LMA-ARM, em Portugal, tratado com a associação do agente hipometilante, azaciditina, e o inibidor BCL2 (venetoclax), o que foi crucial para o tratamento e sobrevivência global do doente, muito além da sobrevivência esperada.

[Synergistic effect of azacitidine with homoharringtonine by activating the c-MYC/DDIT3/PUMA axis in acute myeloid leukemia].

Objective: This study aimed to explore the synergistic effect and underlying mechanism of azacitidine (AZA) in combination with homoharringtonine (HHT) in acute myeloid leukemia (AML) . Methods: The synergistic effects of AZA and HHT were examined by cell proliferation, apoptosis, and colony formation assays. The synergistic effects were calculated using the combination index (CI) , and the underlying mechanisms were explored using RNA sequencing, pathway inhibitors, and gene knockdown approaches. Results: Compared with the single-drug controls, AZA and HHT combination significantly induced cell proliferation arrest and showed a synergistic effect with CI < 0.9 in AML cells. In the combination group versus the single-drug controls, colony formation was significantly decreased, whereas apoptosis was significantly increased in U937 (P<0.001) and MV4-11 (P<0.001) cells. AZA and HHT combination activated the integrated stress response (ISR) signaling pathway and induced DDIT3-PUMA-dependent apoptosis in cells. Furthermore, it remarkably downregulated the expression of c-MYC. The combination also activated c-MYC/DDIT3/PUMA-mediated ISR signaling to induce synergy on apoptosis. The synergy of AZA+HHT on apoptosis was induced by activating c-MYC/DDIT3/PUMA-mediated ISR signaling. Conclusion: The combination of AZA and HHT exerts synergistic anti-AML effects by inhibiting cellular proliferation and promoting apoptosis through activation of the ISR signaling pathway via the c-MYC/DDIT3/PUMA axis.

Pediatric chronic myeloid leukemia in myeloid blast crisis

ABSTRACT Chronic myeloid leukemia (CML) accounts for 2-3% of childhood leukemias. About 5% of cases present in a blastic phase of CML which clinically and morphologically mimics more common acute leukemias of childhood. We report a case of a 3-year-old male who presented with gradual onset swelling of the abdomen and extremities along with generalized weakness. Examination revealed massive splenomegaly, pallor, and pedal edema. Initial workup showed anemia, thrombocytopenia, and leukocytosis (120,000/uL) with a blast percentage of 35%. Blasts were positive for CD13, CD33, CD117, CD34 and HLA-DR, and stained negative for Myeloperoxidase and Periodic Acid Schiff. Fluorescence in situ hybridization was positive for b3a2/e14a2 junction BCR-ABL1 transcript and negative for RUNX1-RUNX1T1/t(8;21), clinching the diagnosis of CML in myeloid blast crisis. The patient expired within 17 days of diagnosis and initiation of therapy.

AKT inhibition interferes with the expression of immune checkpoint proteins and increases NK-induced killing of HL60-AML cells

ABSTRACT Objective To determine the role of the AKT pathway in the regulating of natural Killer-induced apoptosis of acute myeloid leukemia cells and to characterize the associated molecular mechanisms. Methods BALB/c nude mice were injected with HL60 cells to induce a xenogenic model of subcutaneous leukemic tumors. Mice were treated with perifosine, and their spleens were analyzed using biometry, histopathology, and immunohistochemistry. Gene expression analysis in leukemia cells was performed by real-time PCR. Protein analysis of leukemia and natural Killer cells was performed by flow cytometry. AKT inhibition in HL60 cells, followed by co-culture with natural Killer cells was performed to assess cytotoxicity. Apoptosis rate was quantified using flow cytometry. Results Perifosine treatment caused a reduction in leukemic infiltration in the spleens of BALB/c nude mice. In vitro , AKT inhibition reduced HL60 resistance to natural Killer-induced apoptosis. AKT inhibition suppressed the immune checkpoint proteins PD-L1, galectin-9, and CD122 in HL60 cells, but did not change the expression of their co-receptors PD1, Tim3, and CD96 on the natural Killer cell surface. In addition, the death receptors DR4, TNFR1, and FAS were overexpressed by AKT inhibition, thus increasing the susceptibility of HL60 cells to the extrinsic pathway of apoptosis. Conclusion The AKT pathway is involved in resistance to natural Killer-induced apoptosis in HL60 cells by regulating the expression of immune suppressor receptors. These findings highlight the importance of AKT in contributing to immune evasion mechanisms in acute myeloid leukemia and suggests the potential of AKT inhibition as an adjunct to immunotherapy.

Immunophenotypic characterization of acute leukemias in Bahia, Brazil

ABSTRACT Objective To characterize the immunophenotypic profile of acute leukemias in the population of the state of Bahia, Brazil. Methods This is a descriptive, retrospective study. From 2014 to 2018, 796 new cases of acute leukemia were evaluated. The data were obtained from analysis of reports and records of tests performed by flow cytometry immunophenotyping. All individuals of all age groups diagnosed as acute lymphoblastic leukemia or acute myeloid leukemia were included in the study. Demographic variables and expression of leukemia antigens were evaluated. Results Most cases were diagnosed as acute myeloid leukemia and 42.7% as acute lymphoblastic leukemia. Significant differences were found in expression of markers in acute leukemias when age groups were compared, as well as in demographic characteristics. B-cell acute lymphoblastic leukemia was more prevalent than cases of T-cell origin. Assessing the aberrant markers in acute myeloid leukemias, the non-acute promyelocytic leukemia group presented expression of CD7 and CD56 as the most frequent ones. In B-cell acute lymphoblastic leukemia, the most frequent aberrant markers were CD66c, CD13 and CD33. Conclusion Significant differences were found as to several antigens when comparing adults and children, and these findings may contribute to future studies correlating the phenotypic profile to genetic characteristics and therapeutic response, including specific antigen therapies, which may be better targeted.

Expression and clinical significance of Flap endonuclease 1 in acute myeloid leukemia / 肿瘤研究与临床

Objective:To investigate the expression level of flap endonuclease 1 (FEN1) in bone marrow mononuclear cells of patients with acute myeloid leukemia (AML) and its relationship with clinicopathologic features and therapeutic effect, so as to provide a new direction for disease monitoring and targeted therapy in AML patients.Methods:The data of 57 newly treated AML patients and 26 healthy individuals (the healthy control) from the First Clinical College of Guangdong Medical University and Fujian Medical University Union Hospital from November 2018 to December 2020 were retrospectively analyzed. Bone marrow samples of all subjects were collected. Quantitative real-time fluorescence polymerase chain reaction (qRT-PCR) was used to detect FEN1 mRNA expression in bone marrow mononuclear cells of all subjects. Bone marrow samples from 9 newly-diagnosed AML patients and 4 healthy controls were collected, and FEN1 protein expression level was detected by using Western blotting. Differences in FEN1 mRNA expression in AML patients achieving different therapeutic effects were compared among AML patients whose data with evaluable efficacy. AML patients were divided into high FEN1 expression group (≥ critical value) and low FEN1 expression group (< critical value), taking the median relative expression level of FEN1 mRNA as the critical value. The correlation of FEN1 expression level with clinicopathologic features, laboratory indicators, cellular and molecular genetic changes in AML patients at initial diagnosis was analyzed.Results:The median relative expression of FEN1 mRNA in newly treated AML patients was higher than that in healthy controls [0.696 (0.025-3.661) vs. 0.246 (0.013-1.237), Z = 1.75, P = 0.041]. Western blotting showed that the expression level of FEN1 protein in AML patients was higher than that in healthy controls. The relative expression of FEN1 mRNA in 15 recurrent AML patients was higher than that in 19 patients patients achieving complete remission (CR) [1.153 (0.047-4.172) vs. 0.259 (0.023-1.148), Z = 2.71, P = 0.009]. The proportion of patients with French-American-British(FAB) type M 5, fever at initial diagnosis and lymph node enlargement in FEN1 high expression group (32 cases) was higher than that in FEN1 low expression group (25 cases) (all P < 0.05). There were no significant differences in the proportion of gender, age, fatigue, pale skin mucosa and large liver and spleen of patients between the two groups (all P > 0.05). At initial diagnosis, the white blood cell count, lactate dehydrogenase, C-reactive protein and bone marrow primitive cell proportion in FEN1 high expression group were higher than those in FEN1 low expression group (all P < 0.05), and the hemoglobin and platelet count in FEN1 high expression group were lower than those in FEN1 low expression group (all P < 0.05). There were no significant differences in procalcitonin level, the proportion of chromosome karyotype, cytogenetic prognosis grade and patients with or without gene mutation between the two groups (all P > 0.05). Conclusions:FEN1 expression is up-regulated in AML patients and further increased in relapsed patients. FEN1 expression in AML patients is associated with adverse clinicopathological features and poor detection results of laboratory indicators, which may become indicators for disease monitoring in AML patients.

One case of myeloid sarcoma with multiple space occupying lesions in the spinal canal / 中华神经科杂志

Myeloid sarcoma (MS) is a tumor mass formed by the proliferation of one or more myeloid primitive cells outside the marrow, which is mostly related to acute myeloid leukemia (AML). It is reported that 2.5% to 9.1% of AML patients have MS, and AML with spinal canal MS is very rare. Spinal canal MS often has an acute onset and is difficult to diagnose. It is easy to cause missed diagnosis and misdiagnosis, which will lead to a delay in accurate diagnosis seriously affecting the treatment and quality of life among these patients. The clinical data, diagnosis and treatment process of a case of MS with multiple space occupying lesions in the spinal canal diagnosed and treated by the Department of Hematology of Peking Union Medical College Hospital are reported, in order to provide reference for clinical workers.

Efficacy and safety of AZA combined with HHT and LDAC in the treatment of acute myeloid leukemia patients with 3+ 7 conventional regimen intolerance / 中国医师杂志

Objective:To evaluate the efficacy and safety of azacytidine (AZA) combined with homoharringtonine (HHT) and low-dose cytarabine (LDAC) in the treatment of acute myeloid leukemia (AML) patients with 3+ 7 conventional regimen intolerance.Methods:A retrospective analysis was conducted on the clinical characteristics, efficacy, prognosis, and adverse events of 33 AML patients (15 initially diagnosed and 18 relapsed/refractory) admitted to the Second Xiangya Hospital of Central South University.Results:Among the 33 AML patients treated with this regimen, the median age was 55 years old, 9 patients had a moderate cytogenetic risk, and 18 patients had a high cytogenetic risk. Among the 33 patients, 3 were lost to follow-up and 1 had incomplete data. Among the remaining 29 patients who received AZA+ HHT+ LDAC treatment, the total complete response (CR) rate was 69.0%(20/29), and the total response rate (ORR) was 79.3%(23/29); The median progression free survival (PFS) was 7.0 months. Among the subgroup analysis, including age, gender, Eastern Cooperative Oncology Group (ECOG) score, disease classification, bone marrow progenitor cells, peripheral blood leukocytes, risk stratification, and epigenetic abnormalities, only CR rates and PFS differences were statistically significant among different ECOG scoring groups ( P=0.048; P=0.021). A total of 29 patients underwent 69 AZA+ HHT+ LDAC chemotherapy cycles. Retrospective grading was performed on 69 cycles based on common toxicity criteria for adverse events (CTC AE version 5.0). The most common grade Ⅲ-Ⅳ hematological adverse events were thrombocytopenia (54/69, 78.3%) and granulocytopenia (48/69, 69.6%). Common non hematological adverse events included nausea (19/69, 27.5%), infection (17/69, 24.6%), and hypokalemia (18/69, 26.1%). Conclusions:AZA combined with HHT and LDAC has a good therapeutic effect in the treatment of acute myeloid leukemia, and adverse reaction events are controllable.