Mesenchymal Stem Cells for Prophylaxis of Chronic Graft-vs-Host Disease After Haploidentical Hematopoietic Stem Cell Transplant: An Open-Label Randomized Clinical Trial.

Importance: Chronic graft-vs-host disease (GVHD) limits the long-term benefit of haploidentical hematopoietic stem cell transplant (HSCT). This clinical trial evaluated repeated infusions of umbilical cord mesenchymal stem cells (MSCs) during the early stage (45 days and 100 days) after haplo-HSCT to prevent chronic GVHD. Objective: To determine whether repeated infusions of MSCs during the early stage after haplo-HSCT decreases the incidence of severe chronic GVHD. Design, Setting, and Participants: This open-label, multicenter, parallel randomized clinical trial was conducted from April 2016 to January 2022. Eligibility criteria included a diagnosis of acute leukemia and having a haploidentical, suitable related donor for HSCT. The median (range) follow-up time was 39.0 (1.5-67.0) months. Interventions: The enrolled patients with a haploidentical relative for HSCT received the modified busulfan/cyclophosphamide + antithymocyte globulin modified regimen and standard GVHD prophylaxis. Patients were randomly chosen to receive MSCs (the MSC group) (1 × 106 cells/kg, every 2 weeks, starting from 45 days after transplant, 4 times total) or regular prophylaxis (control group). Main Outcome and Measure: The cumulative incidence of severe chronic GVHD. Results: Of 158 patients, 58 (36.7%) were female individuals; the median (range) age for the MSC and control groups was 28 (18-60) years and 28 (18-56) years, respectively. A total of 158 patients were screened, and 148 patients were randomly assigned to the MSC group (n = 74) or control group (n = 74) 1 day before MSCs infusion. The estimated 2-year cumulative incidence of severe chronic GVHD was 5.4% (95% CI, 1.8%-14.0%) in the MSC group and 17.4% (95% CI, 10.1%-28.5%) in the control group (hazard ratio [HR], 0.29; 95% CI, 0.10-0.88; P = .03). There was no difference between the MSC and control groups in the cumulative incidence of leukemia relapse (HR, 1.17; 95% CI, 0.55-2.47; P = .68). The cumulative incidence of stage II to IV acute GVHD in the MSC group was significantly lower than that in the control group (HR, 0.25; 95% CI, 0.09-0.67; P = .01). The MSC group had better GVHD-free and relapse-free survival rates than the control group (HR, 0.62; 95% CI, 0.39-0.98; P = .04). Conclusions and Relevance: The results of this randomized clinical trial show that early repeated infusions of MSCs decreased the incidence and severity of chronic GVHD, and the incidence and severity of acute GVHD manifested as a better GVHD-free and relapse-free survival rate for patients after haplo-HSCT. Trial Registration: Chinese Clinical Trial Registry: ChiCTR-IIR-16007806.

Thrombopoietin receptor agonists for refractory thrombocytopenia in patients after autologous hematopoietic stem cell transplantation.

OBJECTIVE: Autologous hematopoietic stem cell (ASC) transplantation (ASCT) is an effective treatment method for patients with hematological disorders and malignant diseases. The patient's ASCs are harvested prior to radiotherapy/chemotherapy, cryopreserved and then transfused back after the high-dose radiotherapy/chemotherapy conditioning treatment. Since some patients develop thrombocytopenia after receiving ASCT, it is difficult for them to bear simultaneously the management of their original disease and thrombocytopenia. The present study aimed to evaluate the efficacy and safety of thrombocytopenia therapy with thrombopoietin receptor agonists (TPORAs) after ASCT. METHODS: We retrospectively analyzed the clinical safety and efficacy of TPORA treatment for the enrolled 20 patients who developed thrombocytopenia after ASCT. The measured parameters were prolonged isolated thrombocytopenia (PIT), secondary failure of platelet recovery (SFPR) and other calculated response index. Patients with platelet count (PC) ≤ 50×109/L were treated with TPORA, namely with either eltrombopag (Elt), hetrombopag (Het), or avatrobopag (Ava). RESULTS: The group of 20 patients, who received TPORA administration for their thrombocytopenia after ASCT, had a median age of 50 years (ranging between 17 and 60 years). The median administration time of TPORA application was 48 days (ranging from 7 to 451 days); an overall response rate (ORR) was 85% with no response in 15% of patients, while with complete response (CR) in 70% of patients and partial response (PR) in 15% of patients. The median platelet count was 19 × 109/L before TPORA treatment and increased to 87×109)/L after the treatment. The TPORA treatment was safe as only 4 patients (20%) displayed a mild transaminase elevation. No other reported side effects occurred, such as thrombosis, joint pain, diarrhea, and myelofibrosis. It was demonstrated that the short response time to TPORA treatment correlated to the fast platelet recovery, when the number of megakaryocytes in the bone marrow smear exceeded 35/4.5 cm2 under a low magnification of 100 times (p = 0.015). CONCLUSION: TPORA therapy for thrombocytopenia occurring after the radiotherapy/ chemotherapy-conditioned ASCT was well tolerated and effective for platelets recovery.

Azacitidine and lenalidomide combination: a novel relapse prophylaxis regimen after allogeneic hematopoietic stem-cell transplantation in patients with acute myeloid leukemia.

Introduction: While allogeneic hematopoietic stem cell transplantation (allo-HSCT) can be a curative regimen for acute myeloid leukemia (AML), relapse of AML remains a serious risk post-transplantation. Once relapsed, salvage options are limited and management of AML is difficult. Here we designed a prospective study to examine the efficacy and tolerability of maintenance therapy with azacytidine (AZA) plus low-dose lenalidomide (LEN) to prevent relapse after allo-HSCT for AML patients (ChiCTR2200061803). Methods: AML patients post-allo-HSCT were treated with AZA (75 mg/m2 for 7 days), followed by LEN (5 mg/m2, day 10-28), and a 4-week resting interval, which was defined as one treatment cycle. A total of 8 cycles was recommended. Results: 37 patients were enrolled, 25 patients received at least 5 cycles, and 16 patients finished all 8 cycles. With a median follow-up time of 608 (43-1440) days, the estimated 1-year disease free survival (DFS) was 82%, cumulative incidence of relapse (CIR) was 18%, and overall survival (OS) was 100%. Three patients (8%) had grade 1-2 neutropenia without fever; one patient developed grade 3-4 thrombocytopenia and minor subdural hematoma; 4/37 patients (11%) developed chronic GVHD with a score of 1-2, without requiring systemic treatment; No patient developed acute GVHD. After AZA/LEN prophylaxis, increasing numbers of CD56+NK and CD8+ T, and decreasing of CD19+ B cells were observed. Discussion: Azacitidine combined with low-dose lenalidomide was observed to be an effective relapse prophylaxis option after allo-HSCT in AML patients, and can be administered safely without significantly increasing the risk of GVHD, infection and other AEs. Clinical Trial Registration: www.chictr.org, identifier ChiCTR2200061803.

Donor-derived CD19 CAR-T Cells versus Chemotherapy Plus Donor Lymphocyte Infusion for Treatment of Recurrent CD19-positive B-ALL After Allogeneic Hematopoietic Stem Cell Transplantation.

OBJECTIVE: This study aimed to compare the efficacy of anti-CD19 chimeric antigen receptor T cells (CAR-T cells) versus chemotherapy plus donor lymphocyte infusion (chemo-DLI) for treating relapsed CD19-positive B-cell acute lymphoblastic leukemia (B-ALL) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Clinical data of 43 patients with B-ALL who relapsed after allo-HSCT were retrospectively analyzed. Twenty-two patients were treated with CAR-T cells (CAR-T group), and 21 with chemotherapy plus DLI (chemo-DLI group). The complete remission (CR) and minimal residual disease (MRD)-negative CR rates, leukemia-free survival (LFS) rate, overall survival (OS) rate, and incidence of acute graft-versus-host disease (aGVHD), cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) were compared between the two groups. RESULTS: The CR and MRD-negative CR rates in the CAR-T group (77.3% and 61.5%) were significantly higher than those in the chemo-DLI group (38.1% and 23.8%) (P=0.008 and P=0.003). The 1- and 2-year LFS rates in the CAR-T group were superior to those in the chemo-DLI group: 54.5% and 50.0% vs. 9.5% and 4.8% (P=0.0001 and P=0.00004). The 1- and 2-year OS rates in the CAR-T versus chemo-DLI group were 59.1% and 54.5% vs. 19% and 9.5% (P=0.011 and P=0.003). Six patients (28.6%) with grade 2-4 aGVHD were identified in the chemo-DLI group. Two patients (9.1%) in the CAR-T group developed grade 1-2 aGVHD. Nineteen patients (86.4%) developed CRS in the CAR-T group, comprising grade 1-2 CRS in 13 patients (59.1%) and grade 3 CRS in 6 patients (27.3%). Two patients (9.1%) developed grade 1-2 ICANS. CONCLUSION: Donor-derived anti-CD19 CAR-T-cell therapy may be better, safer, and more effective than chemo-DLI for B-ALL patients who relapse after allo-HSCT.

Efficacy and toxicity of CLAG combined with pegylated liposomal doxorubicin in the treatment of refractory or relapsed acute myeloid leukemia.

BACKGROUND: Refractory and relapsed acute myeloid leukemia (r/rAML) is associated with a difficult prognosis; clinical trials are typically suggested despite lack of a recognized standard of care. Combinatorial chemotherapy regimens utilized for r/rAML salvage play a crucial role in battling this invasive phase. Although it is characterized by a low response rate, CLAG is a traditional regimen used in r/rAML. We aimed to compare the efficacy and toxicity of CLAG+PLD to explore whether there was any improvement with the addition of pegylated liposomal doxorubicin (PLD) to CLAG METHODS: A total of 110 r/rAML patients were retrospectively analyzed from February 2017 to June 2020 at the Medical Center of Hematology, XinQiao Hospital, the 303rd Hospital of the Chinese People's Liberation Army, and Central Hospital of Chang Sha, Hunan Province. The response, overall survival (OS), disease-free survival (DFS), and side effects in 110 r/rAML patients were evaluated retrospectively. Of these, 55 patients were administered CLAG+PLD, while 55 patients received CLAG alone as salvage therapy. RESULTS: In the CLAG+PLD group, there were 27 (49.1%) cases of complete response (CR) with no measurable residual disease (MRD-), 12 (21.8%) cases of CR with positive MRD (MRD+), 5 (9.1%) cases of partial response (PR), 11 (20%) cases of no response (NR), and no cases of death during the cycles. The response rates in the CLAG group were lower: CR was reached in 24 (46.6%) patients with MRD-, 6 (10.9%) patients with MRD+, 10 (18.2%) patients with PR, 13 (23.6%) patients with NR, and 2 (3.6%) patients who passed away, one from infection and the other from cerebral hemorrhage. The median OS and DFS were not attained in the CLAG+PLD group during the 2-year OS and DFS follow-up, while both values were 10 months in the CLAG group (p = 0.023 and p = 0.045, respectively). The results of the Cox regression analysis for the CLAG+PLD group were strongly illustrative of the importance of hematopoietic stem cell transplantation (HSCT) following salvage therapy. No increased toxicity was observed in the CLAG+PLD group. CONCLUSION: CLAG+PLD is a potential salvage regimen for r/r AML that has a similar toxicity profile to CLAG and that improves response rates, 2-year OS, and DFS relative to CLAG.

Outcomes of patients with hematological malignancies who undergo unrelated donor hematopoietic stem cell transplantation with ATG-Fresenius versus ATG-Genzyme.

To compare the outcomes of patients with hematological malignancies who received ATG-Fresenius (ATG-F) 20 mg/kg versus those who received ATG-Genzyme (ATG-G) 10 mg/kg in an unrelated donor hematopoietic stem cell transplantation (HSCT) procedure, a total of 186 patients who underwent their first allogeneic HSCT with an unrelated donor were retrospectively analyzed. One hundred and seven patients received ATG-F, and seventy-nine patients received ATG-G. Multivariate analysis showed that the type of ATG preparation had no effect on neutrophil engraftment (P = 0.61), cumulative incidence of relapse (P = 0.092), nonrelapse mortality (P = 0.44), grade II-IV acute graft-versus-host disease (GVHD) (P = 0.47), chronic GVHD (P = 0.29), overall survival (P = 0.795), recurrence-free survival (P = 0.945) or GVHD-free relapse-free survival (P = 0.082). ATG-G was associated with a lower risk of extensive chronic GVHD and a higher risk of cytomegaloviremia (P = 0.01 and HR = 0.41, P < 0.001 and HR = 4.244, respectively). The results of this study suggest that the preparation of rabbit ATG used for unrelated HSCT should be selected based on the incidence of extensive chronic GVHD of each center, and the posttransplant management strategy should be adjusted according to the ATG preparation.

Poor pretransplantation minimal residual disease clearance as an independent prognostic risk factor for survival in myelodysplastic syndrome with excess blasts: A multicenter, retrospective cohort study.

BACKGROUND: Minimal residual disease (MRD) is an important prognostic factor for survival in adults with acute leukemia. The role of pretransplantation MRD status in myelodysplastic syndrome with excess blasts (MDS-EB) is unknown. This study retrospectively analyzed the relationship between pretransplantation MRD status and long-term survival. MATERIALS AND METHODS: Patients with MDS-EB who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) from March 5, 2005, to November 8, 2020, were included. The relationship between pretransplantation MRD status and long-term survival was analyzed using univariate and multivariate logistic regression models. RESULTS: Of 220 patients with MDS-EB who underwent allo-HSCT, 198 were eligible for inclusion in this multicenter, retrospective cohort study. Complete remission was attained in 121 (61.1%) patients, and 103 patients underwent detection of MRD pretransplantation, with 67 patients being MRD-positive and 36 patients being MRD-negative. The median follow-up time was 16 months, the median age was 41 years (6-65 years), and 58% of the patients were men. The 3-year disease-free survival (DFS) and overall survival (OS) probabilities for all patients were 70.1% and 72.9%, respectively. For patients in complete remission, the 3-year DFS and OS probabilities were 72.2% and 74.8%, respectively. Further analysis found that the 3-year DFS rates of MRD-negative and MRD-positive patients were 85.6% and 66.5% (p = .045), respectively, whereas the 3-year OS rates were 91.3% and 66.4% (p = .035), respectively. Univariate and multivariate analyses showed that poor pretransplantation MRD clearance was an independent prognostic risk factor for DFS and OS. CONCLUSION: Poor pretransplantation MRD clearance is an independent prognostic risk factor for long-term survival after allo-HSCT for patients with MDS-EB. PLAIN LANGUAGE SUMMARY: Poor minimal residual disease clearance pretransplanation is an independent prognostic risk factor for long-term survival after allogeneic hematopoietic stem cell transplantation for patients with myelodysplastic syndrome with excess blasts.

Analysis of the Efficacy and Safety of Avatrombopag Combined With MSCs for the Treatment of Thrombocytopenia After Allogeneic Hematopoietic Stem Cell Transplantation.

Platelet graft failure (PGF) is a frequent and serious complication after Allogeneic hematopoietic stem cell transplantation (allo-HSCT) and lacks effective treatment strategies, which could affect the prognosis of patients and even cause death. The exact underlying mechanism of PGF remains unclear, and lacks standard treatment. Here, we conduct a retrospective study to evaluate the efficacy and safety of avatrombopag combined with mesenchymal stem cells (MSCs) in 16 patients with thrombocytopenia after allo-HSCT. Patients were administered the following treatment regimen: 20 mg/d avatrombopag; if the PLT count was less than 50×10^9/L for at least 2 weeks, the dose was increased to 40 mg/d; if the PLT count was 200-400×10^9/L, the dose was reduced; and if the PLT count was greater than 400×10^9/L, avatrombopag was terminated. Umbilical cord MSCs (1×10^6 cells/kg) infusion was performed every week for 4-6 weeks. Among the 16 patients, 13 patients (81.3%) achieved a complete response (CR), 2 patients (12.5%) got a partial response (PR), and 1 patient (6.3%) had no response (NR). The median time to obtain CR was 32 (7-426) days after treatment with avatrombopag combined with umbilical cord MSCs. The time to reach 20×10^9/L≤ PLT <50×10^9/L in the 2 patients with PR was 52 and 230 days after treatment, respectively. One patient had a severe pulmonary infection and died of cytomegalovirus pneumonia. Overall, our results indicated that combination of avatrombopag with MSCs can promote platelet recovery after transplantation, thereby improving the survival rate of patients and improving the quality of life of patients after transplantation, and providing a new method and strategy for the treatment of thrombocytopenia after allo-HSCT.

Novel CD19 chimeric antigen receptor T cells manufactured next-day for acute lymphoblastic leukemia.

Chimeric antigen receptor-engineered T (CAR-T) cells have shown promising efficacy in patients with relapsed/refractory B cell acute lymphoblastic leukemia (R/R B-ALL). However, challenges remain including long manufacturing processes that need to be overcome. We presented the CD19-targeting CAR-T cell product GC007F manufactured next-day (FasTCAR-T cells) and administered to patients with R/R B-ALL. A total of 21 patients over 14 years of age with CD19+ R/R B-ALL were screened, enrolled and infused with a single infusion of GC007F CAR-T at three different dose levels. The primary objective of the study was to assess safety, secondary objectives included pharmacokinetics of GC007F cells in patients with R/R B-ALL and preliminary efficacy. We were able to demonstrate in preclinical studies that GC007F cells exhibited better proliferation and tumor killing than conventional CAR-T (C-CAR-T) cells. In this investigator-initiated study all 18 efficacy-evaluable patients achieved a complete remission (CR) (18/18, 100.00%) by day 28, with 17 of the patients (94.4%) achieving CR with minimal residual disease (MRD) negative. Fifteen (83.3%) remained disease free at the 3-month assessment, 14 patients (77.8%) maintaining MRD negative at month 3. Among all 21 enrolled patients, the median peak of CAR-T cell was on day 10, with a median peak copy number of 104899.5/µg DNA and a median persistence period of 56 days (range: 7-327 days). The incidence of cytokine release syndrome (CRS) was 95.2% (n = 20), with severe CRS occurring in 52.4% (n = 11) of the patients. Six patients (28.6%) developed neurotoxicity of any grade. GC007F demonstrated superior expansion capacity and a less exhausted phenotype as compared to (C-CAR-T) cells. Moreover, this first-in-human clinical study showed that the novel, next-day manufacturing FasTCAR-T cells was feasible with a manageable toxicity profile in patients with R/R B-ALL.

Serum Inflammatory Factor Profiles in the Pathogenesis of High-Altitude Polycythemia and Mechanisms of Acclimation to High Altitudes.

High-altitude polycythemia (HAPC) is a common aspect of chronic mountain sickness (CMS) caused by hypoxia and is the main cause of other symptoms associated with CMS. However, its pathogenesis and the mechanisms of high-altitude acclimation have not been fully elucidated. Exposure to high altitude is associated with elevated inflammatory mediators. In this study, the subjects were recruited and placed into a plain control (PC) group, plateau control (PUC) group, early HAPC (eHAPC) group, or a confirmed HAPC (cHAPC) group. Serum samples were collected, and inflammatory factors were measured by a novel antibody array methodology. The serum levels of interleukin-2 (IL-2), interleukin-3 (IL-3), and macrophage chemoattractant protein-1 (MCP-1) in the eHAPC group and the levels of interleukin-1 beta (IL-1 beta), IL-2, IL-3, tumor necrosis factor-alpha (TNF-alpha), MCP-1, and interleukin-16 (IL-16) in the cHAPC group were higher than those in the PUC group. More interestingly, the expression of IL-1 beta, IL-2, IL-3, TNF-alpha, MCP-1, and IL-16 in the PUC group showed a remarkable lower value than that in the PC group. These results suggest that these six factors might be involved in the pathogenesis of HAPC as well as acclimation to high altitudes. Altered inflammatory factors might be new biomarkers for HAPC and for high-altitude acclimation.

High-dose Chemotherapy Combined with Autologous Hematopoietic Stem Cell Transplantation as Frontline Therapy for Intermediate/High-risk Diffuse Large B Cell Lymphoma.

The role of autologous hematopoietic stem cell transplantation (auto-HSCT) following high-dose chemotherapy has been validated and accepted as a standard treatment for patients with relapsed diffuse large B-cell lymphoma (DLBCL). However, its clinical efficacy as frontline therapy remains to be elucidated. This study aimed to examine the feasibility of frontline auto-HSCT for newly diagnosed intermediate/high-risk DLBCL patients. We retrospectively reviewed the data of 223 patients treated with frontline auto-HSCT or chemotherapy alone (year 2008-2014) from four hospitals. The median follow-up time was 29.4 months. Between the two treatment arms among the intermediate/high-risk DLBCL patients, the 3-year overall survival (OS) and progression-free survival (PFS) rates of patients given frontline auto-HSCT were 87.6% and 81.9%, respectively, and the chemotherapy-alone group showed 3-year OS and PFS rates of 64.9% and 59.59%, respectively. Compared with the chemotherapy-alone group, the frontline auto-HSCT could eliminate the adverse impact of non-germinal center B-cell (GCB) type. In addition, in the frontline auto-HSCT group, patients who achieved complete response (CR) at auto-HSCT had a longer survival time than those who did not achieve CR. Our results suggested that frontline auto-HSCT could improve the prognosis of intermediate/high-risk DLBCL patients.

Donor-derived CD19 CAR-T cell therapy of relapse of CD19-positive B-ALL post allotransplant.

Safety and efficacy of allogeneic anti-CD19 chimeric antigen receptor T cells (CAR-T cells) in persons with CD19-positive B-cell acute lymphoblastic leukemia (B-ALL) relapsing after an allotransplant remain unclear. Forty-three subjects with B-ALL relapsing post allotransplant received CAR-T cells were analyzed. 34 (79%; 95% confidence interval [CI]: 66, 92%) achieved complete histological remission (CR). Cytokine release syndrome (CRS) occurred in 38 (88%; 78, 98%) and was ≥grade-3 in 7. Two subjects died from multiorgan failure and CRS. Nine subjects (21%; 8, 34%) developed ≤grade-2 immune effector cell-associated neurotoxicity syndrome (ICANS). Two subjects developed ≤grade-2 acute graft-versus-host disease (GvHD). 1-year event-free survival (EFS) and survival was 43% (25, 62%). In 32 subjects with a complete histological remission without a second transplant, 1-year cumulative incidence of relapse was 41% (25, 62%) and 1-year EFS and survival, 59% (37, 81%). Therapy of B-ALL subjects relapsing post transplant with donor-derived CAR-T cells is safe and effective but associated with a high rate of CRS. Outcomes seem comparable to those achieved with alternative therapies but data from a randomized trial are lacking.

Tandem autologous hematopoietic stem cell transplantation for treatment of adult T-cell lymphoblastic lymphoma: a multiple center prospective study in China.

T-cell lymphoblastic lymphoma (T-LBL) is a highly aggressive form of lymphoma with poor clinical outcomes and lacks of a standard treatment regimen. In this study, we assessed the safety and efficacy of tandem autologous hematopoietic stem cell transplantation (auto-HSCT) strategy for adult T-LBL and evaluated prognostic factors affecting survival. 181 Newly-diagnosed adult T-LBL patients were enrolled, 89 patients were treated with chemotherapy alone, 46 patients were allocated to single auto-HSCT group, 46 patients were treated with tandem auto-HSCT. The median follow-up time was 37 months, the 3-year progression/relapse rate of the tandem auto-HSCT group was significantly lower than that of the single auto-HSCT group and chemotherapy group (26.5% vs 53.1% and 54.8%). The 3-year PFS and OS rate of the tandem auto-HSCT group (73.5% and 76.3%) were significantly higher than those of the single auto-HSCT group (46.9% and 58.3%) and the chemotherapy group (45.1% and 57.1%). In the tandem auto-HSCT group, age and disease status after the first transplantation impacted the OS and PFS. Multivariate analysis identified that disease status after the first transplantation was the only independent prognostic factor for patients treated with tandem-HSCT. In addition, diagnostic models of the initial CD8+CD28+/CD8+CD28- T cell ratio in predicting the disease status were found to be significant. Taken together, tandem auto-HSCT can be considered an optimal strategy for adult T-LBL patients (ChiCTR-ONN-16008480).

Plasmacytoid Dendritic Cell Infiltration in Acute Myeloid Leukemia.

INTRODUCTION: Increasing evidence has demonstrated that plasmacytoid dendritic cells (PDCs) in the tumor microenvironment (TME) play an important role in tumorigenesis and progression. PDC infiltration has been found in certain malignancies such as classic Hodgkin's lymphoma and chronic myelomonocytic leukemia. Our previous work reported that PDC infiltration could occur in acute myeloid leukemia (AML), but the clinical significance of PDC in AML has not been thoroughly investigated. PATIENTS AND METHODS: Here, we evaluated the clinical significance of PDC to AML transition in a leukemia microenvironment. The frequency of PDCs in 80 acute myelomonocytic leukemia (AML-M4) and 83 acute monocytic leukemia (AML-M5) patients was determined by flow cytometry. RESULTS: We found 62 cases with PDC infiltration. These patients showed higher numbers of bone marrow blasts, higher mean Hb concentration, and required more cycles of chemotherapy before achieving complete remission (CR), but had lower white blood cell and platelet counts compared to patients without PDC infiltration. Drug sensitivity analysis showed that patients with PDC infiltration had lower sensitivity to standard chemotherapy regimens. Kaplan-Meier survival curves demonstrated that patients with PDC infiltration had a shorter overall survival (OS) time and progression-free survival time. DISCUSSION: These results suggested that PDC infiltration can be used for risk stratification of AML-M4/M5, and PDCs may transdifferentiate into leukemia in an AML microenvironment.

Is It Better to Mobilize Hematopoietic Stem Cells With Pegfilgrastim in Healthy Donors During Allogeneic Hematopoietic Stem Cell Transplantation?

The mobilization of hematopoietic stem cells (HSCs) using granulocyte colony-stimulating factor is a classic method. Recently, a single injection of pegfilgrastim was used to mobilize CD34+ cells in some small-sample studies. To confirm the efficacy and safety of pegfilgrastim in the mobilization of CD34+ cells from healthy donors, we conducted a retrospective multicenter study. A total of 146 healthy donors who all received subcutaneous pegfilgrastim (12 mg) on day 1 were enrolled in our study. Donor HSC apheresis was conducted on day 5. The primary endpoint was the percentage of donors from whom ≥4 × 106 CD34+ cells/kg were collected in a single apheresis session. The median number of CD34+ cells in donors was significantly higher on day 5 than that on day 4 (82.26 µL vs. 51.65 µL, P ¡ 0.001). In 111 of the 146 donors, an optimal number of CD34+ cells (≥4 × 106 kg) were collected in a single apheresis procedure. Bone pain and headache were the main adverse events, but the side effects did not require treatment. The number of white blood cells in most donors dropped to normal levels within 1 week after apheresis. Nearly 97% of patients achieved neutrophil and platelet engraftment. Pegfilgrastim for mobilization could be used to obtain an optimal number of CD34+ cells in a single session. Pegfilgrastim-induced mobilization not only was effective and safe but also avoided the pain of multiple injections and apheresis procedures in donors. However, prospective randomized controlled trials should be conducted in the future.

Effect of rhG-CSF Combined With Decitabine Prophylaxis on Relapse of Patients With High-Risk MRD-Negative AML After HSCT: An Open-Label, Multicenter, Randomized Controlled Trial.

PURPOSE: Relapse is a major cause of treatment failure after allogeneic hematopoietic stem-cell transplantation (allo-HSCT) for high-risk acute myeloid leukemia (HR-AML). The aim of this study was to explore the effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) combined with minimal-dose decitabine (Dec) on the prevention of HR-AML relapse after allo-HSCT. PATIENTS AND METHODS: We conducted a phase II, open-label, multicenter, randomized controlled trial. Two hundred four patients with HR-AML who had received allo-HSCT 60-100 days before randomization and who were minimal residual disease negative were randomly assigned 1:1 to either rhG-CSF combined with minimal-dose Dec (G-Dec group: 100 µg/m2 of rhG-CSF on days 0-5 and 5 mg/m2 of Dec on days 1-5) or no intervention (non-G-Dec group). The primary outcome was relapse after transplantation, and the secondary outcomes were chronic graft-versus-host disease (cGVHD), safety of the treatment, and survival. RESULTS: The estimated 2-year cumulative incidence of relapse in the G-Dec group was 15.0% (95% CI, 8.0% to 22.1%), compared with 38.3% (95% CI, 28.8% to 47.9%) in the non-G-Dec group (P < .01), with a hazard ratio (HR) of 0.32 (95% CI, 0.18 to 0.57; P < .01). There was no statistically significant difference between the G-Dec and non-G-Dec groups in the 2-year cumulative incidence of cGVHD without relapse (23.0% [95% CI, 14.7% to 31.3%] and 21.7% [95% CI, 13.6% to 29.7%], respectively; P = .82), with an HR of 1.07 (95% CI, 0.60 to 1.92; P = .81). After rhG-CSF combined with minimal-dose Dec maintenance, increasing numbers of natural killer, CD8+ T, and regulatory T cells were observed. CONCLUSION: Our findings suggest that rhG-CSF combined with minimal-dose Dec maintenance after allo-HSCT can reduce the incidence of relapse, accompanied by changes in the number of lymphocyte subtypes.

Plasma circulating tumor DNA assessment reveals KMT2D as a potential poor prognostic factor in extranodal NK/T-cell lymphoma.

BACKGROUND: The early detection of tumors upon initial diagnosis or during routine surveillance is important for improving survival outcomes. Here, we investigated the feasibility and clinical significance of circulating tumor DNA (ctDNA) detection for Extranodal NK/T-cell lymphoma, nasal type (ENTKL). METHODS: The plasma ctDNA assessment was based on blood specimens collected from 65 newly diagnosed patients with ENKTL in the hematology medical center of Xinqiao Hospital. Longitudinal samples collected under chemotherapy were also included. The gene mutation spectrum of ENKTL was analyzed via next generation sequencing. RESULTS: We found that the most frequently mutated genes were KMT2D (23.1%), APC (12.3%), ATM (10.8%), ASXL3 (9.2%), JAK3 (9.2%), SETD2 (9.2%), TP53 (9.2%) and NOTCH1 (7.7%). The mutation allele frequencies of ATM and JAK3 were significantly correlated with the disease stage, and mutated KMT2D, ASXL3 and JAK3 were positively correlated with the metabolic tumor burden of the patients. Compared with the tumor tissue, ctDNA profiling showed good concordance (93.75%). Serial ctDNA analysis showed that treatment with chemotherapy could decrease the number and mutation allele frequencies of the genes. Compared with PET/CT, ctDNA has more advantages in tracking residual disease in patients. In addition, patients with mutated KMT2D had higher expression compared with those with wild type, and mutated KMT2D predicted poor prognosis. CONCLUSION: Our results unveil the mutation spectrum of ENKTL patients' plasma, which can be used to monitor the disease status of the patients exactly, and KMT2D is the most frequently mutated gene with prognosis prediction value. The application of ctDNA sequencing can provide precision treatment strategies for patients. TRIAL REGISTRATION: This study is registered with chictr.org (ChiCTR1800014813, registered 7 February, 2018-Retrospectively registered).

miR-203a-3p.1 is involved in the regulation of osteogenic differentiation by directly targeting Smad9 in MM-MSCs.

MicroRNAs (miRNAs) have emerged as important regulators of bone development and regeneration. The aim of the present study was to determine whether miR-203a-3p.1 is involved in osteogenic differentiation of multiple myeloma (MM)-mesenchymal stem cells (MSCs) and the potential underlying mechanism. MSCs were isolated from patients with MM and normal subjects and confirmed by flow cytometry using specific surface markers. The osteogenic differentiation capacity of MM-MSCs was identified by Alizarin Red S calcium deposition staining and reverse transcription-quantitative PCR (RT-qPCR) of typical osteoblast differentiation markers. The role of miR-203a-3p.1 in the osteoblast differentiation of MM-MSCs was determined by gain or loss of function experiments. The target of miR-203a-3p.1 was identified using bioinformatics (including the miRNA target prediction database TargetScan, miRDB, DIANA TOOLS and venny 2.1.0), luciferase reporter assay, RT-qPCR and western blotting. The expression levels of proteins involved in the Wnt3a/ß-catenin signaling pathway were detected by western blot analysis. The results revealed that the osteogenic differentiation capacity of MM-MSCs was reduced when compared with normal (N)-MSCs, as demonstrated by a decrease in calcium deposition and mRNA expression of typical osteoblast differentiation markers, including ALP, OPN and OC. In addition, miR-203a-3p.1 was downregulated in N-MSCs following osteoblast induction, whereas no changes were observed in MM-MSCs. The downregulation of miR-203a-3p.1 resulted in increased osteogenic potential, as indicated by the increase in the mRNA expression levels of the typical osteoblast differentiation markers, including alkaline phosphatase (ALP), osteopontin (OPN) and osteocalcin (OC). Bioinformatics and luciferase reporter assay analysis indicated that mothers against decapentaplegic homolog 9 (Smad9) may be a direct target of miR-203a-3p.1 in N-MSCs. The RT-qPCR and western blot assays revealed that overexpression of smad9 significantly enhanced the effect of miR-203a-3p.1 inhibitors on osteoblast markers, which indicated that miR-203a-3p.1 inhibitors may regulate the osteogenic differentiation of MM-MSCs by upregulating Smad9. In addition, the Wnt3a/ß-catenin signaling pathway was activated following miR-203a-3p.1 inhibition. These results suggest that miR-203a-3p.1 may serve an important role in the osteogenic differentiation of MM-MSCs by regulating Smad9 expression.