Wogonin induces mitochondrial apoptosis and synergizes with venetoclax in diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is among the most aggressive hematological malignancies and patients are commonly treated with combinatorial immunochemotherapies such as R-CHOP. Till now, the prognoses are still variable and unsatisfactory, depending on the molecular subtype and the treatment response. Developing effective and tolerable new agents is always urgently needed, and compounds from a natural source have gained increasing attentions. Wogonin is an active flavonoid extracted from the traditional Chinese herbal medicine Scutellaria baicalensis Georgi and has shown extensive antitumor potentials. However, the therapeutic effect of wogonin on DLBCL remains unknown. Here, we found that treatment with wogonin dose- and time-dependently reduced the viability in a panel of established DLBCL cell lines. The cytotoxicity of wogonin was mediated through apoptosis induction, along with the loss of mitochondrial membrane potential and the downregulation of BCL-2, MCL-1, and BCL-xL. In terms of the mechanism, wogonin inhibited the PI3K and MAPK pathways, as evidenced by the clear decline in the phosphorylation of AKT, GSK3ß, S6, ERK, and P38. Furthermore, the combination of wogonin and the BCL-2 inhibitor venetoclax elicited synergistically enhanced killing effect on DLBCL cells regardless of their molecular subtypes. Finally, administration of wogonin significantly impeded the progression of the DLBCL tumor in a xenograft animal model without obvious side effects. Taken together, the present study suggests a promising potential of wogonin in the treatment of DLBCL patients either as monotherapy or an adjuvant for venetoclax-based combinations.

NL101 synergizes with the BCL-2 inhibitor venetoclax through PI3K-dependent suppression of c-Myc in acute myeloid leukaemia.

BACKGROUND: Acute myeloid leukaemia (AML) comprises a group of heterogeneous and aggressive haematological malignancies with unsatisfactory prognoses and limited treatment options. Treatments targeting B-cell lymphoma-2 (BCL-2) with venetoclax have been approved for patients with AML, and venetoclax-based drug combinations are becoming the standard of care for older patients unfit for intensive chemotherapy. However, the therapeutic duration of either single or combination strategies is limited, and the development of resistance seems inevitable. Therefore, more effective combination regimens are urgently needed. METHODS: The efficacy of combination therapy with NL101, a SAHA-bendamustine hybrid, and venetoclax was evaluated in preclinical models of AML including established cell lines, primary blasts from patients, and animal models. RNA-sequencing and immunoblotting were used to explore the underlying mechanism. RESULTS: NL101 significantly potentiated the activity of venetoclax in AML cell lines, as evidenced by the enhanced decrease in viability and induction of apoptosis. Mechanistically, the addition of NL101 to venetoclax decreased the stability of the antiapoptotic protein myeloid cell leukaemia-1 (MCL-1) by inhibiting ERK, thereby facilitating the release of BIM and triggering mitochondrial apoptosis. Moreover, the strong synergy between NL101 and venetoclax also relied on the downregulation of c-Myc via PI3K/Akt/GSK3ß signalling. The combination of NL101 and venetoclax synergistically eliminated primary blasts from 10 AML patients and reduced the leukaemia burden in an MV4-11 cell-derived xenograft model. CONCLUSIONS: Our results encourage the pursuit of clinical trials of combined treatment with NL101 and venetoclax and provide a novel venetoclax-incorporating therapeutic strategy for AML.

The transplantation effect of pegylated granulocyte colony-stimulating factor mobilized hematopoietic stem cells may be superior to that of G-CSF mobilized hematopoietic stem cells in haploidentical allogeneic hematopoietic cell transplantation.

Granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood stem cells have become the preferred source of hematopoietic stem cells. We compared the effectiveness of G-CSF and pegylated G-CSF (peg-G-CSF) for hematopoietic stem cell mobilization in haploidentical hematopoietic stem cell transplantation (haplo-HSCT) donors, and evaluated the transplant outcomes. We conducted a matched retrospective cohort study. Donors mobilized with peg-G-CSF (n = 70) and G-CSF (n = 70). 140 consecutive patients diagnosed with acute leukemia who underwent haplo-HSCT were included in this study. The findings revealed that the peg-G-CSF cohort exhibited significantly elevated myeloid-derived suppressor cells (MDSCs) levels in their grafts when compared to the G-CSF cohort (P < 0.001). The 100-day cumulative incidence (CI) of grade III-IV acute graft-versus-host disease (GVHD) and 1-year CI of moderate-to-severe chronic GVHD were 4.3% vs 14.3 % (P = 0.047) and 11.2% vs 27.4 % (P = 0.023), in the peg-G-CSF group and G-CSF group. Patients reveiving mobilized stem cell with peg-G-CSF had a significantly greater likelihood of 1-year GVHD-free relapse-free survival (GRFS) compared to patients reveiving mobilized stem cell with G-CSF (74.9% vs 37.9 %, P < 0.001). The higher graft MDSCs proportion was associated with lower grade II-IV aGVHD, cGVHD (P < 0.05) and higher GRFS in the univariate analysis (P < 0.05). Multivariate analysis showed that MDSCs proportion higher than 11.36 % (HR, 0.305; 95 % CI, 0.154-0.606; P = 0.001) and peg-G-CSF for stem cell mobilization (HR, 0.466; 95 % CI, 0.251-0.865; P = 0.016) were independent prognostic factors of GRFS. The superior survival rates observed in recipients of peg-G-CSF-mobilized cells are likely due to reduced acute GVHD, potentially mediated by the increased MDSCs within the grafts.

High expression of EBP is an adverse prognostic factor for de novo acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) is a heterogeneous disease, for which identifying reliable prognostic markers is critical for accurate clinical prognosis and treatment optimization. The inhibition of emopamil-binding protein gene (EBP) expression has been demonstrated to induce cancer cell death via depleting downstream sterols. Nevertheless, no comprehensive studies have been conducted specifically in tumors, including AML. METHOD: Herein, survival analyses were performed on the dataset obtained from The Cancer Genome Atlas (TCGA). Besides, the EBP levels were quantified using real-time qPCR in a cohort of 120 AML patients, and the value of EBP was further assessed using our clinical data. RESULTS: Patients with high EBP expression had worse overall survival (OS) and event-free survival (EFS) than patients with low EBP expression, both in the TCGA dataset and our clinical data. Additionally, white blood cell (WBC) counts were higher in patients with high EBP expression (P = 0.032). Moreover, in patients with intermediate-risk AML, it was discovered that elevated EBP expression was linked to a worse EFS (P = 0.038). Multivariate analysis demonstrated that high EBP expression was an independent prognostic factor in AML patients and was associated with a shorter OS and EFS (OS: P = 0.041; EFS: P = 0.017). Furthermore, the data revealed that transplantation in the high-EBP group led to an improvement in survival (OS: P = 0.001; EFS: P = 0.001). The same benefit was also observed in intermediate-risk AML patients (OS: P = 0.026; EFS: P = 0.026). CONCLUSION: Collectively, our findings indicated that high expression of EBP in AML patients was an adverse prognostic factor, but transplantation had the otential to alleviate its negative effects.

Reduced-toxicity conditioning regimen with low dose post-transplantation cyclophosphamide and low-dose anti-thymocyte globulin as graft-versus-host disease prophylaxis for haploidentical stem cell transplantation in older patients.

Reduced-toxicity conditioning (RIC) regimens are used for allogeneic hematopoietic stem cell transplantation in older patients. However, successful outcomes are hindered by graft-versus-host disease (GVHD), treatment-related mortality, and relapse, particularly after haploidentical donor hematopoietic stem cell transplantation (HID-HSCT). The aim of this study was to evaluate the effectiveness of an RIC conditioning regimen that included a combination of cyclosporin A, methotrexate (on day + 1), mycophenolate, lower doses of post-transplantation PTCy (40 mg/kg on day + 3), and ATG (7.5 mg/kg) as GVHD prophylaxis prior to haplo-stem cell transplantation (haplo-SCT) in older patients. METHODS: We retrospectively analyzed outcomes in 55 patients ≥ 55 years of age with hematologic malignancies treated with fludarabine, cytarabine, busulfan, and low-dose cyclophosphamide as the conditioning regimen between January 1, 2019, and November 30, 2023. RESULTS: Neutrophil engraftment was successful in all patients within 28 days, with 54 patients (98.2%) achieving complete donor chimerism. The cumulative incidence of non-relapse mortality was 0% at 30 days, 7.5% at 100 days, and 19% at 1 year. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was 25% (95%CI, 15-38%), whereas that of grade III-IV aGVHD was 9.1% (95% CI, 3.3-19%). The cumulative incidence of extensive chronic graft-versus-host disease at 1 year was 3.6% (95%CI, 0.66-11%). The cumulative incidences of relapse, overall survival, and GVHD-free/relapse-free survival at 1 year were 9.0%, 71.6%, and 67.1%, respectively. CONCLUSIONS: An RIC conditioning regimen, including a combination of lower PTCy/ATG as GVHD prophylaxis, followed by haplo-SCT, might be a promising option for appropriately selected older patients.

Prognostic Significance of Dual-Specificity Phosphatase 23 Expression in Acute Myeloid Leukemia.

Background: Recently, an increasing number of studies have suggested dual-specificity phosphatase 23 (DUSP23) is a critical factor in the development of diffuse connective tissue disease and may be a valuable biomarker for primary human cancers. However, there is a lack of comprehensive studies on the prognostic significance of DUSP23 expression in acute myeloid leukemia (AML). Methods: RNA sequencing data from The Cancer Genome Atlas (TCGA) (AML = 173), Genotype-Tissue Expression (GTEx) (healthy controls = 70) and GEO (AML = 461, healthy controls = 76) databases were used to compare DUSP23 expression between AML patients and healthy controls. The overall survival (OS) of DUSP23 in AML was evaluated using Kaplan-Meier Cox regression. Furthermore, univariate Cox regression and multivariate Cox regression analysis were used to determine whether DUSP23 was an independent prognostic factor for AML. We then verified the expression level and prognostic significance of DUSP23 in our cohort (AML = 128, healthy controls = 31). In addition, functional enrichment analysis of DUSP23-related DEGs was performed through gene set enrichment analysis (GSEA) and protein-protein interaction (PPI) network analysis. Results: The expression level of DUSP23 is significantly higher in AML patients than in healthy controls in TCGA, GTEx, GEO databases and our cohort. By multivariate analysis, high expression of DUSP23 is a poor prognostic indicator of OS in the TCGA database. Next, we verified the role of DUSP23 as an adverse prognostic biomarker in our cohort. Enrichment analysis of related genes showed that DUSP23 may regulate important signal pathways in hematological tumors including the MAPK pathways. It is suggested by the PPI network that DUSP23, along with IMP3, MRPL4, MRPS12, POLR2L, and ATP5F1D may play a role in the process of AML. Conclusion: The study demonstrated high expression of DUSP23 could serve as a poor independent prognostic biomarker in AML.

Successful treatment pure red cell aplasia after ABO major mismatched allogeneic hematopoietic stem cell transplantation with avatrombopag and low dose rituximab.

BACKGROUND: Pure red cell aplasia (PRCA) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) with ABO major incompatibility is characterized by transfusion dependent anemia. No standard treatment existed for PRCA following allo-HSCT yet. STUDY DESIGN AND METHODS: We conducted a retrospective study, and reported our experience with the use of avatrombopag and lower dose rituximab to treat five patients with PRCA subsequent to major ABO-incompatible allo-HSCT. RESULTS: Five cases of PRCA were identified from 72 patients who underwent allo-HSCT with major or bidirectional ABO mismatch. Cumulative incidence at Day +60 was 6.9% (5/72) at our center. All donor and recipient blood groups were A+  and O+ , respectively. In the first three cases we reported, patients received erythropoietin, plasma exchange, and donor lymphocyte infusion, but none of them had any effect. After 4 weeks of treatment with low dose rituximab (100 mg/week) combined with avatrombopag (40 mg/day), favorable outcomes were obtained. According to the aforementioned experience, Cases 4 and 5 were administered low-dose rituximab and avatrombopag in 3 months after transplantation, and erythroid response was observed on 3 weeks after treatment. Our patients tolerated low-dose rituximab and avatrombopag well and experienced rapid efficacy, with a median duration of 3 weeks. Furthermore, no severe infection or thrombocytosis necessitated a dose adjustment. CONCLUSION: Low-dose rituximab and avatrombopag may be an effective treatment for patients with PRCA after major ABO-incompatible allo-HSCT. The patients should be treated at least 90 days post transplantation if conventional erythropoietin therapy fails.

Licochalcone A induces mitochondria-dependent apoptosis and interacts with venetoclax in acute myeloid leukemia.

The management of patients with acute myeloid leukemia (AML) remains a challenge because of the complexity and heterogeneity of this malignancy. Despite the recent approval of several novel targeted drugs, resistance seems inevitable, and clinical outcomes are still suboptimal. Increasing evidence supports the use of natural plants as an important source of anti-leukemic therapeutics. Licochalcone A (LCA) is an active flavonoid isolated from the roots of licorice, Glycyrrhiza uralensis Fisch., possessing extensive anti-tumor activities. However, its effects on AML and the underlying mechanisms remain unknown. Here, we showed that LCA decreased the viability of established human AML cell lines in a dose- and time-dependent manner. LCA significantly induced mitochondrial apoptotic cell death, accompanied by the downregulation of MCL-1, upregulation of BIM, truncation of BID, and cleavage of PARP. A prominent decline in the phosphorylation of multiple critical molecules, including AKT, glycogen synthase kinase-3ß (GSK3ß), ERK, and P38 was observed upon LCA treatment, indicating PI3K and MAPK signals were suppressed. Both transcription and translation of c-Myc were also inhibited by LCA. In addition, LCA enhanced the cytotoxicity of the BCL-2 inhibitor venetoclax. Furthermore, the anti-survival and pro-apoptotic effects were confirmed in primary blasts from 10 patients with de novo AML. Thus, our results expand the applications of LCA, which can be regarded as a valuable agent in treating AML.

Etoposide combined with cytarabine and pegfilgrastim for poorly mobilizing patients with multiple myeloma and lymphoma: A prospective multicentre study.

A chemotherapy-based mobilization regimen in patients who mobilize poorly, based on etoposide, cytarabine and pegfilgrastim (EAP), has recently been introduced. The aim of this prospective study was to investigate the efficacy and safety of the EAP regimen in patients with poorly mobilizing multiple myeloma (MM) or lymphoma. This single-arm clinical trial was performed at eight public hospitals in China and was registered as a clinical trial (NCT05510089). The inclusion criteria were; (1) diagnosis of MM or lymphoma, (2) defined as a 'poor mobilizer' and (3) aged 18-75 years. The EAP regimen consisted of etoposide 75 mg/m2/day on days 1-2, cytarabine 300 mg/m2 every 12 h on days 1-2 and pegfilgrastim 6 mg on day 6. The primary endpoint of the study was the ratio of patients achieving adequate mobilization (≥2.0 × 106 CD34+ cells/kg). From 1 September 2022 to 15 August 2023, a total of 58 patients were enrolled, 53 (91.4%) achieved adequate mobilization, while 41 (70.7%) achieved optimal mobilization with a median number of cumulative collected CD34+ cells was 9.2 (range 2.1-92.7) × 106/kg and the median number of apheresis per patient of 1.2. The median time from administration of the EAP regimen to the first apheresis was 12 days. Approximately 8.6% of patients required plerixa for rescue, which was successful. Twelve (20.7%) of the 58 patients suffered grade 2-3 infections, while 25 (43.1%) required platelet transfusions. The duration of neutrophil and platelet engraftment was 11 days. In conclusion, these results suggest that the EAP mobilization regimen might be a promising option for poorly mobilizing patients with MM or lymphoma.

The Proportion of Myeloid-derived Suppressor Cells in the Graft as a Potential Predictor of Acute Graft-versus-host Disease in Haploid Allogeneic Hematopoietic Stem Cell Transplantation.

Myeloid-derived suppressor cells (MDSC) are powerful immunomodulatory cells that play an important role in infectious and inflammatory disorders, but the correlation between graft MDSC amount and early transplant outcomes remains unknown in allogeneic hematopoietic stem cell transplantation. We collected data from 91 patients with acute leukemia undergoing haploidentical allogeneic hematopoietic stem cell transplantation. The grafts were analyzed in terms of CD34+ cells, CD3+ T cells and subpopulation, and MDSC (HLA-DR -/low CD33 + CD16 - ) by flow cytometry. The cutoff value of the MDSC proportion in the graft on the receiver operating curve was 8.89%, with a sensitivity of 0.833 and specificity of 0.852. Day +100 cumulative incidences of II-IV and III-IV acute graft-versus-host disease (aGVHD) in the low MDSC group were 73.5% and 38.8%, respectively, and that in the high MDSC group were 5.3% and 0%, with a significant difference in incidences of II-IV and III-IV aGVHD ( P <0.001). The overall survival, relapse-free survival, and GVHD-relapse-free survival (GRFS) at 1 year were 66.3% versus 80.5% ( P =0.043), 71.6% versus 71.7% ( P =0.248), and 22.1% versus 62.8% ( P <0.001), respectively. No significant difference in the cumulative incidence of relapse between the 2 groups was observed. Multivariate analysis revealed that higher MDSC proportions were associated with a lower risk of II-IV aGVHD. Graft MDSC proportion exceeding 8.89% was significantly associated with higher overall survival and GRFS. The prophylaxis of antithymocyte globulin+post-transplant cyclophosphamide and higher MDSC proportion in the graft were favorable factors for improving GRFS. In conclusion, graft MDSC proportion may be a significant predictor of aGVHD.

Effectiveness of single-dose 6 mg pegfilgrastim in mobilizing peripheral blood stem cells in allogeneic hematopoietic cell transplantation donors.

A single injection of 12 mg pegfilgrastim was used to mobilize peripheral blood progenitor cells (PBPCs) from healthy donors in some studies. The purpose of this study was to determine if 6 mg of pegfilgrastim was effective and safe for mobilizing CD34+ cells in donors for allogeneic hematopoietic stem cell transplantation. We conducted a retrospective case-matched design. A single dosage of 6 mg pegfilgrastim was used to mobilize PBPCs from 60 healthy donors. Granulocyte colony-stimulating factor (G-CSF, 10 µg/kg) was administered daily to the matched donors. Leukapheresis was scheduled to commence on day 4 of the mobilization regimen. The median yielded CD34+ cell in the pegfilgrastim group was higher than those in the G-CSF group, at 5.06 × 106/kg recipient weight. The 73.3% of donors mobilized with pegfilgrastim yielded >4 × 106 cells/kg CD34+ cells in a single apheresis procedure when compared to the 33.3% of donors mobilized with G-CSF (P < 0.001). The myeloid-derived suppressor cells (MDSC) proportion in the pegfilgrastim group was significantly higher than that in the G-CSF group (P < 0.001). The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was higher in the G-CSF group than that in the pegfilgrastim group (26.7% vs. 11.7%), without statistical difference. In comparison to the G-CSF group, the pegfilgrastim group had a reduced median pain intensity numerical rating scale score (1 vs. 2). A single 6 mg dosage of pegfilgrastim is effective and safe for allogeneic PBPCs collection from healthy donors. Pegfilgrastim may decrease the incidence of aGVHD by boosting MDSCs, which need further investigation.

The kava chalcone flavokawain B exerts inhibitory activity and synergizes with BCL-2 inhibition in malignant B-cell lymphoma.

BACKGROUND: B-cell lymphoma, which originates from B cells at diverse differentiation stages, is the most common non-Hodgkin lymphoma with tremendous treatment challenges and unsatisfactory clinical outcomes. Flavokawain B (FKB), a naturally occurring chalcone extracted from kava, possesses promising anticancer properties. However, evidence on the effects of FKB on hematological malignancies, particularly lymphomas, remains scarce. PURPOSE: This study aimed to investigate the antilymphoma effect of FKB and its underlying mechanisms. STUDY DESIGN/METHODS: Proliferation assays, flow cytometry, and western blotting were employed to determine whether and how FKB affected B-cell lymphoma cell lines in vitro. Xenograft mouse models were established to evaluate the antilymphoma efficacy of FKB in vivo. RESULTS: FKB reduced the viability of a panel of B-cell lymphoma cell lines in a dose- and time-dependent manner. Mitochondrial apoptosis was markedly induced by FKB, as evidenced by an increased percentage of annexin V-positive cells, a loss of mitochondrial membrane potential, and cleavage of caspase-3 and PARP. Moreover, FKB inhibited BCL-XL expression and synergized with the BCL-2 inhibitor ABT-199. Mechanistically, FKB treatment decreased the phosphorylation of Akt, mammalian target of rapamycin (mTOR), glycogen synthase kinase-3ß (GSK3ß), and ribosomal protein S6 (RPS6). Pharmacological blockage of phosphoinositide 3-kinase (PI3K), Akt, or GSK3ß potentiated the activity of FKB, indicating the involvement of the PI3K/Akt cascade in FKB-mediated inhibitory effects. In mouse xenograft models, the intraperitoneal administration of FKB significantly decreased lymphoma growth, accompanied by diminished mitosis and Ki-67 staining of tumor tissues. CONCLUSION: Our data demonstrate the robust therapeutic potential of FKB in the treatment of B-cell lymphoma.

Platycodin D induces apoptotic cell death through PI3K/AKT and MAPK/ERK pathways and synergizes with venetoclax in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a highly heterogeneous and rapidly progressive hematopoietic neoplasm characterized by frequent relapses and variable prognoses. The development of new treatment options, therefore, is of crucial importance. Platycodin D (PD) is a triterpenoid saponin, extracted from the roots of the traditional Chinese herbal medicine Platycodon grandiflorum (Jacq.) A. DC., which has been reported to exhibit therapeutic potential against a broad range of cancers. Although the effects of PD on AML remain unclear, in the present study, we observed a concentration-dependent reduction in the viability of multiple human AML cell lines in response to treatment with PD. In addition to triggering mitochondria-dependent apoptosis via the upregulation of BAK and BIM, treatment with PD also induced cell cycle arrest at the G0/G1 phase. Western blot analyses revealed marked suppression of the phosphorylation of protein kinase B (AKT), glycogen synthase kinase-3ß, ribosomal protein S6, and extracellular signal-regulated kinase (ERK) by PD, in turn implying the participation of the phosphoinositide 3-kinase (PI3K)/AKT and mitogen-activated protein kinase (MAPK)/ERK pathways. Pre-incubation with LY294002, MK2206, AR-A014418, or U0126 was consistently found to significantly aggravate PD-induced inhibition of viability. Additionally, PD combined with the B-cell lymphoma 2 (BCL2) inhibitor venetoclax elicited synergistically enhanced cytotoxic effects. The anti-leukemic activity of PD was further validated using primary samples from de novo AML patients. Given the results of the present study, PD may be a potent therapeutic candidate for the treatment of AML.

Intensified conditioning regimen with fludarabine combined with post-transplantation cyclophosphamide for haploidentical allogeneic hematopoietic stem cell transplantation in children with high-risk acute leukemia.

OBJECTIVE: Post-transplantation cyclophosphamide (PTCy) can reduce the incidence of graft versus host disease (GVHD) and this intervention is often applied on adults with hematologic malignancy. However, the high relapse rate hinders the development of the intervention and data of PTCy used on children with hematologic malignancy remains limited. In order to overcome issue of high relapse rate in PTCy treatment, we used fludarabine (Flu), enhanced dose of cytarabine (Ara-C, 9 g/m2), busulfan (Bu), Cy, anti-thymocyte globulin (ATG) combined with PTCy for an intensified conditioning regimen. METHODS: A total of 22 children with acute leukemia received intensified PTCy conditioning regimen (PTCy intensified group). We matched with 18 children who received modified Bu-Cy and ATG conditioning regimen in the same period (ATG group). RESULTS: The two-year cumulative incidences of grade II-IV acute GVHD was significantly lower in PTCy intensified group (13.6 ± 7.7% vs 38.9 ± 11.5%, P = 0.048). Two-year GVHD-free relapse free survival (GRFS) in PTCy seems to be better among the increment group despite not being significant (63.3 ± 10.3% vs 35.4 ± 11.9%, P = 0.092). The positive rate of minimal residual disease after transplantation was significantly lower than that before transplantation (20.0% vs 2.5%, P = 0.029). CONCLUSION: In conclusion, ATG and PTCy combined with Flu-based increased intensity conditioning regimen is effective for acute leukemia in children. It could reduce GVHD rate significantly and potentially improve GRFS.

Higher efficacy of Etoposide + Cytarabine Plus Pegfilgrastim in poorly mobilizing Multiple Myeloma and lymphoma Patients.

BACKGROUND AIMS: An optimal strategy for mobilizing hematopoietic stem cells in poorly mobilizing patients with multiple myeloma (MM) and lymphoma has not yet been determined. METHODS: We retrospectively analyzed the efficacy and safety of etoposide combined with cytarabine (etoposide 75 mg/m2, daily d1∼2; Ara-C 300 mg/m2, every 12 h d1∼2), plus pegfilgrastim (6 mg d6) in 32 patients with MM or lymphoma, among whom 53.1% were defined as "proven poor mobilizers." RESULTS: This approach resulted in adequate mobilization (≥2.0 × 106 CD34+ cells/kg) in 93.8% of patients and optimal mobilization (≥5.0 × 106 CD34+ cells/kg) in 71.9% of patients. A total of 100% of patients with MM reached at least 5 × 106 CD34+ cells/kg collected, the amount required for double autologous stem cell transplant. In total, 88.2% of patients with lymphoma reached at least 2 × 106 CD34+ cells/kg collected, the amount required for a single autologous stem cell transplant. This was achieved with a single leukapheresis in 78.1% of cases. A median peak number of 42.0/µL circulating CD34+ cells and a median number of blood CD34+ cells counts in 6.7 × 106/L were collected among 30 successful mobilizers. Approximately 6.3% of patients required plerixafor rescue, which was successful. Nine (28.1%) of the 32 patients suffered grade 2∼3 infections, and 50% required platelet transfusions. CONCLUSIONS: We conclude that chemo-mobilization with etoposide, Ara-C and pegfilgrastim in poorly mobilizing patients with MM or lymphoma is very effective and has acceptable toxicity.

Loss of IRF8 inhibits the growth of acute myeloid leukemia cells.

The transcription factor interferon regulatory factor 8 (IRF8), as a member of the IRF family, is essential for myeloid cell differentiation. However, the precise role of IRF8 in the pathogenesis of acute myeloid leukemia (AML) remains unknown. By using multivariate analysis, we discovered that high IRF8 expression was an independent poor predictor of overall survival (OS) in AML patients from our clinical follow-up study. The proliferation of three AML cell lines was significantly inhibited by shRNA-mediated knockdown of IRF8, owing to cell cycle S-phase arrest. Furthermore, we demonstrated that knocking down IRF8 could suppress the expression of CyclinA and CyclinB1, resulting in a shift in cell cycle distribution. Loss of IRF8 in AML cells decreased the expression of STAT3 and phosphor-STAT3 (pSTAT3), which are key factors in JAK/STAT signal pathway and are important for AML progression. Using a xenograft mouse model, we discovered the antiproliferative effect of losing IRF8 in vivo. In conclusion, this study found that IRF8 may play a prognostic factor and therapeutic target in AML.

High Expression of CD300A Predicts Poor Survival in Acute Myeloid Leukemia.

INTRODUCTION: Recent studies have suggested that CD300A was an oncogene in acute myeloid leukemia (AML) development. However, the clinical relevance and biological insight into CD300A expression in AML are still not well understood. The present study aimed to examine the expression characteristics of CD300A in AML and confirmed its clinical significance for AML. METHODS: Quantification of the CD300A transcript was performed in 119 AML patients by real-time quantitative PCR in bone marrow blasts. The predictive significance of CD300A expression on the clinical outcomes of AML was assessed using overall survival (OS) and relapse-free survival (RFS). The published Cancer Genome Atlas (TCGA) data were used as an external validation for survival analysis and pathway analyses. RESULTS: In comparison with monocytes from healthy peripheral blood cells, the expression levels of CD300A in AML cells were higher. Patients in the intermediate and adverse risk categories by WHO criteria (2018) had higher CD300A expression levels than those in the favorable risk category (p < 0.001). AML patients with high expression of CD300A had a higher early death rate (p = 0.029), lower complete remission rate (p = 0.042), higher death rate (p < 0.001) and relapse rate (p = 0.002), and shorter OS (p < 0.0001) and RFS (p < 0.0001). Through multivariable analysis, high CD300A expression in AML was also an independent poor prognostic factor. The CAMP and CGMP-PKG signaling pathways may be stimulated by increased CD300A expression levels, which may be important for the development of AML. CONCLUSIONS: The expression levels of CD300A were associated with risk stratification and the clinical relevance of AML. High CD300A expression may act as an independent adverse prognostic factor for OS and RFS in AML.

[Clinical Value of Translocator Protein Gene in Evaluating the Efficacy of FLT3-ITD/DNMT3A R882 Double-Mutated Acute Myeloid Leukemia].

OBJECTIVE: To observe the clinical significance of translocator proteins (TSPO) gene in the treatment of FLT3-ITD/DNMT3A R882 double-mutated acute myeloid leukemia (AML). METHODS: Seventy-six patients with AML hospitalized in the Department of Hematology of the Affiliated People's Hospital of Ningbo University from June 2018 to June 2020 were selected, including 34 patients with FLT3-ITD mutation, 27 patients with DNMT3A R882 mutation, 15 patients with FLT3-ITD/DNMT3A R882 double mutation, as well as 19 patients with immune thrombocytopenia (ITP) hospitalized during the same period as control group. RNA was routinely extracted from 3 ml bone marrow retained during bone puncture, and TSPO gene expression was detected by transcriptome sequencing (using 2-deltadeltaCt calculation). RESULTS: The expression of TSPO gene in FLT3-ITD group and DNMT3A R882 group at first diagnosis was 2.02±1.04 and 1.85±0.76, respectively, which were both higher than 1.00±0.06 in control group, but the differences were not statistically significant (P=0.671, P=0.821). The expression of TSPO gene in the FLT3-ITD/DNMT3A R882 group was 3.98±1.07, wich was significantly higher than that in the FLT3-ITD group and DNMT3A R882 group, the differences were statistically significant (P=0.032, P=0.021). The expression of TSPO gene in patients who achieved complete response after chemotherapy in the FLT3-ITD/DNMT3A R882 group was 1.19±0.87, which was significantly lower than that at first diagnosis, and the difference was statistically significant (P=0.011). CONCLUSION: TSPO gene may be used as an indicator of efficacy in FLT3-ITD /DNMT3A R882 double-mutated AML.