[The consensus of allogeneic hematopoietic transplantation for hematological diseases in China(2016)-- post- transplant leukemia relapse]

Preemptive interferon-α therapy could prevent relapse of acute myeloid leukemia following allogeneic hematopoietic stem cell transplantation: A real-world analysis

Introduction

Measurable residual disease (MRD)-directed interferon-a treatment (i.e. preemptive IFN-α treatment) can eliminate the MRD in patients with acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Therefore, this study aimed to further assess its efficacy in a multicenter retrospective study in a real-world setting.

Methods

A total of 247 patientswho received preemptive IFN-α treatment were recruited from 4 hospitals in China. The protocols for MRD monitoring mainly based on quantitative polymerase chain reaction [qPCR] and multiparameter flow cytometry [MFC].

Results

The median duration of IFN-α treatment was 56 days (range, 1-1211 days). The cumulative incidences of all grades acute graft-versus-host disease (aGVHD), all grades chronic graft-versus-host disease (cGVHD), and severe cGVHD at 3 years after IFN-α therapy were 2.0% (95% confidence interval [CI], 0.3-3.8%), 53.2% (95% CI, 46.8-59.7%), and 6.2% (95% CI, 3.1-9.2%), respectively. The cumulative incidence of achieving MRD negative state at 2 years after IFN-α treatment was 78.2% (95% CI, 72.6-83.7%). The 3-year cumulative incidences of relapse and non-relapse mortality following IFN-α therapy were 20.9% (95% CI, 15.5-26.3%) and 4.9% (95%CI, 2.0-7.7%), respectively. The probabilities of leukemia-free survival and overall survival at 3 years following IFN-α therapy were 76.9% (95% CI, 71.5-82.7%) and 84.2% (95% CI, 78.7-90.1%), respectively. Multivariable analysis showed that MRD positive state by qPCR and MFC before IFN-α treatment, high-risk disease risk index before allo-HSCT, and receiving identical sibling donor HSCT were associated with a higher risk of relapse and a poorer leukemia-free survival. Severe cGVHD was associated with an increased risk of non-relapse mortality.

Discussion

Thus, real-world data suggest that preemptive IFN-α is effective for treating patients with AML with MRD after allo-HSCT.

Monitoring of post-transplant MLL-PTD as minimal residual disease can predict relapse after allogeneic HSCT in patients with acute myeloid leukemia and myelodysplastic syndrome

Background

The mixed-lineage leukemia (MLL) gene is located on chromosome 11q23. The MLL gene can be rearranged to generate partial tandem duplications (MLL-PTD), which occurs in about 5-10% of acute myeloid leukemia (AML) with a normal karyotype and in 5-6% of myelodysplastic syndrome (MDS) patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently one of the curative therapies available for AML and MDS with excess blasts (MDS-EB). However, how the prognosis of patients with high levels of MLL-PTD after allo-HSCT, and whether MLL-PTD could be used as a reliable indicator for minimal residual disease (MRD) monitoring in transplant patients remains unknown. Our study purposed to analyze the dynamic changes of MLL-PTD peri-transplantation and the best threshold for predicting relapse after transplantation.

Methods

We retrospectively collected the clinical data of 48 patients with MLL-PTD AML or MDS-EB who underwent allo-HSCT in Peking University People’s Hospital. The MLL-PTD was examined by real-time quantitative polymerase chain reaction (RQ-PCR) at the diagnosis, before transplantation and the fixed time points after transplantation. Detectable MLL-PTD/ABL > 0.08% was defined as MLL-PTD positive in this study.

Results

The 48 patients included 33 AML patients and 15 MDS-EB patients. The median follow-up time was 26(0.7-56) months after HSCT. In AML patients, 7 patients (21.2%) died of treatment-related mortality (TRM), 6 patients (18.2%) underwent hematological relapse and died ultimately. Of the 15 patients with MDS-EB, 2 patients (13.3%) died of infection. The 3-year cumulative incidence of relapse (CIR), overall survival (OS), disease-free survival (DFS) and TRM were 13.7 ± 5.2, 67.8 ± 6.9, 68.1 ± 6.8 and 20.3% ± 6.1%, respectively. ROC curve showed that post-transplant MLL-PTD ≥ 1.0% was the optimal cut-off value for predicting hematological relapse after allo-HSCT. There was statistical difference between post-transplant MLL-PTD ≥ 1.0% and MLL-PTD < 1.0% groups (3-year CIR: 75% ± 15.3% vs. 0%, P < 0.001; 3-year OS: 25.0 ± 15.3% vs. 80.7% ± 6.6%, P < 0.001; 3-year DFS: 25.0 ± 15.3% vs. 80.7 ± 6.6%, P < 0.001; 3-year TRM: 0 vs. 19.3 ± 6.6%, P = 0.277). However, whether MLL-PTD ≥ 1% or MLL-PTD < 1% before transplantation has no significant difference on the prognosis.

Conclusions

Our study indicated that MLL-PTD had a certain stability and could effectively reflect the change of tumor burden. The expression level of MLL-PTD after transplantation can serve as an effective indicator for predicting relapse.

The Potential Roles of Mucosa-Associated Invariant T Cells in the Pathogenesis of Gut Graft-Versus-Host Disease After Hematopoietic Stem Cell Transplantation

Gut acute graft-versus-host disease (aGVHD) is a serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with high mortality. Mucosa-associated invariant T (MAIT) cells are a group of innate-like T cells enriched in the intestine that can be activated by riboflavin metabolites from various microorganisms. However, little is known about the function or mechanism of action of MAIT cells in the occurrence of gut aGVHD in humans. In our study, multiparameter flow cytometry (FCM) was used to evaluate the number of MAIT cells and functional cytokines. 16S V34 region amplicon sequencing analysis was used to analyze the intestinal flora of transplant patients. In vitro stimulation and coculture assays were used to study the activation and function of MAIT cells. The number and distribution of MAIT cells in intestinal tissues were analyzed by immunofluorescence technology. Our study showed that the number and frequency of MAIT cells in infused grafts in gut aGVHD patients were lower than those in no-gut aGVHD patients. Recipients with a high number of MAITs in infused grafts had a higher abundance of intestinal flora in the early posttransplantation period (+14 days). At the onset of gut aGVHD, the number of MAIT cells decreased in peripheral blood, and the activation marker CD69, chemokine receptors CXCR3 and CXCR4, and transcription factors Rorγt and T-bet tended to increase. Furthermore, when gut aGVHD occurred, the proportion of MAIT17 was higher than that of MAIT1. The abundance of intestinal flora with non-riboflavin metabolic pathways tended to increase in gut aGVHD patients. MAIT cells secreted more granzyme B, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ under the interleukin (IL)-12/IL-18 stimulation [non-T-cell receptor (TCR) signal] and secreted most of the IL-17 under the cluster of differentiation (CD)3/CD28 stimulation (TCR signal). MAIT cells inhibited the proliferation of CD4+ T cells in vitro. In conclusion, the lower number of MAIT cells in infused grafts was related to the higher incidence of gut aGVHD, and the number of MAIT cells in grafts may affect the composition of the intestinal flora of recipients early after transplantation. The flora of the riboflavin metabolism pathway activated MAIT cells and promoted the expression of intestinal protective factors to affect the occurrence of gut aGVHD in humans.

Stanozolol and Danazol Have Different Effects on Hematopoiesis in the Murine Model of Immune-Mediated Bone Marrow Failure

Background: Stanozolol and danazol are widely used in the treatment of aplastic anemia; however, their mechanisms of action are unclear.

Methods: Bone marrow mononuclear cells from 10 patients newly diagnosed with aplastic anemia and 10 healthy volunteers were collected and cultured together with stanozolol, danazol, or blank control separately for marrow colony assays. K562 cell lines that had been incubated with stanozolol, danazol, or blank control were tested for erythroid or megakaryocytic differentiation. Meanwhile, CB6F1/Crl mice were injected with 1 × 10⁶ C57BL/6 donor-originated lymphocytes after irradiation with 5 Gy total body irradiation to establish a model for immune-mediated bone marrow failure (aplastic anemia mouse model). Mice with aplastic anemia were treated with cyclosporin A monotherapy, cyclosporin A in combination with stanozolol, and cyclosporin A in combination with danazol for 30 days. Peripheral blood cell counts once a week and bone marrow colony assays at the end of 1 month were performed. The proportion of T cell subsets, level of inflammatory factors, erythropoietin, and thrombopoietin were detected before and after treatment. The levels of erythropoietin receptors on bone marrow mononuclear cells after treatment were tested using western blotting.

Results: In the ex vivo experiments, the number of burst-forming units-erythroid; colony-forming units-granulocyte and macrophage; and colony-forming units-granulocyte, erythrocyte, monocyte, and megakaryocyte in the patients with aplastic anemia were significantly lower than that in the normal controls (P < 0.05). However, the number of colonies and mean fluorescence intensity of CD235a or CD41 expression in the harvested cultured cells were not significantly different among the different treatment groups in the patients with aplastic anemia, normal controls, and K562 cell lines. These results show that stanozolol and danazol produce no direct hematopoiesis-stimulating effects on progenitor cells. In the in vivo experiment, the mice with aplastic anemia treated with cyclosporin A and danazol exhibited the most rapid recovery of platelet; the platelet count returned to normal levels after 3 weeks of treatment, which was at least 1 week earlier than in the other groups. In contrast, mice treated with cyclosporin A and stanozolol exhibited the highest hemoglobin level at the end of treatment (P < 0.05). Bone marrow colony assays at 30 days showed that the number of burst-forming units-erythroid was the highest in mice treated with cyclosporin A and stanozolol, while the number of colony-forming units-granulocyte and macrophage was the highest in those treated with cyclosporin A and danazol. Compared to cyclosporin A monotherapy, additional stanozolol and danazol can both increase the level of regulatory T cells and upregulate interleukin-10, inhibiting the expression of tumor necrosis factor-α (P < 0.05). However, IL-2 was more effectively reduced by danazol than by stanozolol (P < 0.05). The cyclosporin A- and stanozolol-treated mice showed higher serum erythropoietin (corrected by hemoglobin level) and higher erythropoietin receptor levels in bone marrow mononuclear cells than the other groups (P < 0.05).

Conclusions: Neither stanozolol nor danazol directly stimulated hematopoiesis in vitro. However, in vivo, stanozolol may exhibit an advantage in improving erythropoiesis, while danazol may induce stronger effects on platelets. Both danazol and stanozolol exhibited immunosuppressive roles. Stanozolol could enhance the secretion of erythropoietin and expression of erythropoietin receptor in bone marrow mononuclear cells.

[Clinical observation of 12 patients with refractory/relapsed acute myeloid leukemia treated with allogeneic hematopoietic stem cell transplantation containing cladribine regimen]

Objective: To investigate the safety and efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) containing cladribine sequential busulfan regimen for refractory/relapsed acute myeloid leukemia (AML) . Methods: The clinical data of 12 refractory/relapsed AML patients received allo-HSCT with cladribine sequential busulfan regimen. Results: ① Of the 12 patients, 9 were males and 3 females, with a median age of 36 (27-50) years. The donors were identical sibling (3) , matched unrelated (1) and haploidentical family member (9) respectively. Nine patients reached partial remission and other remained no remission after chemotherapy before allo-HSCT. The median previous chemotherapy courses before allo-HSCT were 6 (2-13) . ② Conditioning regimen: Smostine 250 mg·m(-2)·d(-1), d-7; Cladribine 5 mg·m(-2)·d(-1), d-6 to d-2; Cytarabine Arabinoside 2 g·m(-2)·d(-1), d-6 to d-2; Busulfan 3.2 mg·m(-2)·d(-1), d-6 to d-3; Rabbit anti-human thymocyte immunoglobulin (ATG) 1.5 mg·m(-2)·d(-1) (unrelated donor transplantation) or 2.0-2.5 mg·m(-2)·d(-1) (haplo-HSCT) , d-4 to d-1. ③ Of the 12 patients, 11 patients attained complete haploidentical engraftment, one case occurred primary graft failure. The median durations for neutrophils and platelet implantations were 15 (15-21) and 19 (17-30) days respectively. ④After conditioning, no hepatic veno-occlusive diseases were observed, hemorrhagic cystitis occurred in 2 patients, 8 patients had fever, 3 cases experienced acute GVHD grade II, localized chronic GVHD occurred in 8 patients. ⑤The median follow-up was 8 (4-12) months. Leukemia relapse occurred in 2 patients at time of 6, 12 months after allo-HSCT. The estimated 1-year OS and DFS were (71.1±1.8) % and (62.2±1.8) %, respectively. Conclusions: allo-HSCT with cladribine sequential busulfan regimen was a feasible choice with favorable outcome for refractory/relapsed AML.

[An interlaboratory comparison study on the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels]

Objective: To investigate the current status and real performance of the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels in China through interlaboratory comparison. Methods: Peking University People's Hospital (PKUPH) prepared the samples for comparison. That is, the fresh RUNX1-RUNX1T1 positive (+) bone morrow nucleated cells were serially diluted with RUNX1-RUNX1T1 negative (-) nucleated cells from different patients. Totally 23 sets with 14 different samples per set were prepared. TRIzol reagent was added in each tube and thoroughly mixed with cells for homogenization. Each laboratory simultaneously tested RUNX1-RUNX1T1 and WT1 transcript levels of one set of samples by real-time quantitative PCR method. All transcript levels were reported as the percentage of RUNX1-RUNX1T1 or WT1 transcript copies/ABL copies. Spearman correlation coefficient between the reported transcript levels of each participated laboratory and those of PKUPH was calculated. Results: ①RUNX1-RUNX1T1 comparison: 9 samples were (+) and 5 were (-) , the false negative and positive rates of the 20 participated laboratories were 0 (0/180) and 5% (5/100) , respectively. The reported transcript levels of all 9 positive samples were different among laboratories. The median reported transcript levels of 9 positive samples were from 0.060% to 176.7%, which covered 3.5-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.5 to 12.3 (one result which obviously deviated from other laboratories' results was not included) , 85% (17/20) of the laboratories had correlation coefficient ≥0.98. ②WT1 comparison: The median reported transcript levels of all 14 samples were from 0.17% to 67.6%, which covered 2.6-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.3-13.7, 62% (13/21) of the laboratories had correlation coefficient ≥0.98. ③ The relative relationship of the reported RUNX1-RUNX1T1 transcript levels between the participants and PKUPH was not always consistent with that of WT1 transcript levels. Both RUNX1-RUNX1T1 and WT1 transcript levels from 2 and 7 laboratories were individually lower than and higher than those of PKUPH, whereas for the rest 11 laboratories, one transcript level was higher than and the other was lower than that of PKUPH. Conclusion: The reported RUNX1-RUNX1T1 and WT1 transcript levels were different among laboratories for the same sample. Most of the participated laboratories reported highly consistent result with that of PKUPH. The relationship between laboratories of the different transcript levels may not be the same.

[Effects of pre-transplant course on prognosis of allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia]

Objective: To evaluate the impact of pre-transplant course on transplant outcomes in patients with acute myeloid leukemia (AML) . Methods: A retrospective analysis was conducted in 107 patients with AML who received allogeneic hematopoietic stem cells transplantation (allo-HSCT) in the first complete remission stage (CR(1)) from January 2012 to June 2014. Results: ①46 cases received allo-HSCT within 6 months upon diagnosis, including 25 males and 21 females, with a median age of 26 (12-60) y. 61 cases received allo-HSCT after 6 months upon diagnosis, including 34 males and 27 females, with a median age of 31 (14-58) years. There is no statistical significance in patients' age, gender, NCCN risk stratification, courses for induction, minimal residual disease (MRD) status, transplantation type and infection rates prior to transplantation. Total courses of chemotherapy before allo-HSCT were 4 (3-5) and 5 (4-10) for the two groups, respectively. ②Incidences of Grade Ⅱ-Ⅳ aGVHD were 26.09% (12/46) for the <6-month group and 24.59% (15/61) for the ≥6 months group (P=0.860) . Incidences of Grade Ⅲ/Ⅳ aGVHD were 2.17% (1/46) for the <6-month group and 14.75% (9/61) for the ≥6 months group (P=0.027) . ③ Probabilities of 2-year overall survival (OS) were (90.3±4.6) % for the <6 months group and (75.7±5.7) % for the ≥6 months group (P=0.042) . Probabilities of 2-year disease-free survival (DFS) were (90.7±4.4) % for the <6 months group and (76.3±5.5) % for the ≥6 months group (P=0.038) . ④ During the median follow-up of 863 (26-2 026) days, cumulative incidences of non-relapse mortality were (4.4±3.1) % for the <6 months group and (18.2±5.0) % for the ≥6 months group (P=0.047) . ⑤ Univariate analysis showed that age, NCCN risk stratification, MRD status before transplantation and rates of infection was not related to transplantation outcomes. Chemotherapy courses before allo-HSCT (≤4 or >4) was related to OS and DFS (P=0.044, P=0.039) , but not to NRM (P=0.079) . Conclusion: AML patients who obtained CR(1) could achieve better long-term survival by receiving allo-HSCT within 6 months after diagnosis.

[Allogeneic hematopoietic stem cell transplantation for treatment of refractory and relapsed acute myeloid leukemia: outcomes and prognostic factors]

目的

评价异基因造血干细胞移植（allo-HSCT）治疗难治/复发急性髓系白血病（AML）的疗效，并对预后相关因素进行分析。

方法

回顾性分析allo-HSCT治疗99例难治/复发AML患者总体生存（OS）率、无病生存（DFS）率、移植物抗宿主病（GVHD）发生率、移植相关死亡率（TRM）及复发率，并分析影响预后的危险因素。

结果

全部99例患者中男59例，女40例，中位年龄为35（6~58）岁，均接受清髓性预处理。所有患者中性粒细胞均达植入标准，中位植活时间为14（9~25）d。移植后100 d Ⅱ~Ⅳ度急性GVHD累积发生率为27.3%（95% CI 18.9%~36.3%）；2年慢性GVHD累积发生率为33.9%（95%CI 24.6%~43.5%），其中广泛型慢性GVHD累积发生率为9.3%（95%CI 4.5%~16.1%）。移植后3年OS、DFS、TRM率分别为45.0%（95%CI 34.6%~55.4%）、45.0%（95%CI 34.8%~55.2%）、19.7%（95%CI 12.4%~28.3%），复发率为36.6%（95%CI 26.9%~46.4%）。多因素分析显示，影响OS的独立危险因素包括移植前未缓解[P=0.009，HR=2.21（95%CI 1.22~4.04）]、初诊WBC>50×10⁹/L[P=0.024，HR=2.11（95%CI 1.11~4.02）]、供者年龄>35岁[P=0.031，HR=1.96（95%CI 1.06~3.60）]、移植后未发生慢性GVHD[P=0.008，HR=0.38（95%CI 0.18~0.78）]。根据移植前危险因素（移植前未缓解、初诊WBC>50×10⁹/L、供者年龄>35岁）进行危险度分组，具有0、1、2~3个危险因素患者的3年OS率分别为75.0%、46.9%、15.4%（χ²=26.873，P<0.001）。

结论

allo-HSCT是挽救性治疗难治/复发AML的有效手段，复发是影响生存的主要原因。移植前缓解状态、发病时WBC水平、供者年龄及移植后是否发生慢性GVHD是难治/复发AML患者allo-HSCT预后的独立影响因素。

[Prognostic significance of early phase donor chimerism after allogeneic peripheral blood stem cell transplantation]

Objective: To evaluate the prognostic significance of early phase full donor chimerism (FDC) after myeloablative allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Methods: The clinical data of 72 hematological patients received myeloablative allo-PBSCT from Feb. 2016 to Jul. 2017 were analyzed retrospectively. The median age was 36.5 years (range 4-59), 44 were males and 28 females. Of the donors, there were 35 HLA matched sibling donors, 27 haploidentical donors and 10 unrelated donors. Polymerase chain reaction amplification of short tandem repeat sequence (PCR-STR) was used to detect donor cell chimerism (DC) rate of recipient bone marrow at one, two and three months after transplantation. Results: The median follow-up was 462 d (range: 47-805 d), 55 cases were still alive, and 45 cases were disease-free survival (DFS) at the end of follow-up. The 2-year overall survival (OS) and DFS were (68.9±7.7)% and (59.5±6.3)%, respectively. A number of 16 cases underwent relapses, with 2-year cumulative incidence of (24.1±5.3)%. The median time of recurrence was 157(32-374) d. Forty cases (55.6%) developed acute graft-versus-host diseases (aGVHD), with median time of 35.5 (13-90) d. Chronic GVHD (cGVHD) occurred in 23 patients (31.9%), with median time of 169 (94-475) d. Univariate analysis found the following factors were not related to OS, DFS or relapse rate (RR), including age, sex, blood type and sex of donor-recipient, occurrence of aGVHD and cGVHD. The OS and DFS in cases reached FDC and no FDC at two months after transplantation were (85.2±6.9)% vs (66.1±7.7)% (P=0.051) and (76.7±7.7)% vs (48.9±8.1)% (P=0.021), respectively. The RR rate in FDC group was lower than that in no FDC group [(16.6±6.8)% vs (30.4±7.8)%, P=0.187, respectively]. Conclusion: The present study confirmed the important value for predicting the prognosis with whether or not the patients reached FDC at the early phase after allo-PBSCT. The OS and DFS in cases with FDC at two months after transplantation were significantly higher than those of no FDC patients.