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.

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.

Dihydropyrimidinase-like 2 can serve as a novel therapeutic target and prognostic biomarker in acute myeloid leukemia.

BACKGROUND: Identifying therapeutic targets and prognostic biomarkers significantly contributes to individualized treatment of acute myeloid leukemia (AML). Dihydropyrimidinase-like 2 (DPYSL2) expression was decreased in homoharringtonine (HHT)-resistant AML cells, which were established by our group. DPYSL2 plays an important role in axon growth and has oncogene effect in glioblastoma. However, little research has been conducted to investigate the function of DPYSL2 in AML pathogenesis. METHODS: Auto-docking was used to reveal the targeting relationship between HHT and DPYSL2. Overall survival (OS), event-free survival (EFS), and relapse-free survival (RFS) were used to evaluate the prognostic impact of DPYSL2 for AML. ShRNA was used to knockdown the expression of SPATS2L. Apoptosis was assessed by flow cytometry. In vivo growth and survival were assessed using a xenotransplantation mice model. RNA sequencing was performed to elucidate the molecular mechanisms underlying the role of SPATS2L in AML and were confirmed by Western blot. RESULTS: We found DPYSL2 was the target of HHT. Next, we found AML cell lines and patients had higher DPYSL2 expression levels than the normal samples. Further multivariate analysis demonstrated that high DPYSL2 expression was an independent poor prognostic factor for OS, EFS, and RFS in AML. Inhibition of DPYSL2 expression suppressed cell growth, induced apoptosis in AML cell lines, and prolonged the survival of AML xenograft NCG mice. Through RNA-seq analysis from TCGA and our data, the JAK2/STAT3/STAT5-PI3K P85/AKT/GSK3b axis was thought to be the critical pathway in regulating DPYSL2 in AML development. CONCLUSIONS: We first time confirmed that DPYSL2 was a target of HHT and played an oncogene role in AML by regulating JAK/STAT signaling pathway. Therefore, DPYSL2 could serve as a novel prognostic marker and therapeutic target for AML treatment.