A real-world study of infectious complications of venetoclax combined with decitabine or azacitidine in adult acute myeloid leukemia.

PURPOSE: The purpose of this study was to identify the incidence, sites and main pathogens, and risk factors for infectious complications occurring in patients with adult acute myeloid leukemia (AML) during the first course of venetoclax combined with decitabine or azacitidine. METHODS: A retrospective cohort analysis was performed of 81 patients with AML older than 14 years who received the first cycle of venetoclax combined with a hypomethylating agent (HMA) between March 2018 and March 2021 at our institution. Infectious complications, if any, were documented. RESULTS: Among a total of 81 cases of AML, 59 (72.8%) patients occurred infections, including fever without an identifiable source (28.8%), clinically documented infections (40.7%), and microbiologically documented infections (30.5%). The most commonly isolated organism in culture was Candida albicans, followed by Klebsiella pneumonia, and Pseudomonas aeruginosa. The 4-week and 8-week mortality rates were 3.7% and 7.4%, respectively. In multivariate analysis, a high proportion of blasts in bone marrow, decreased hemoglobin level, and fever with or without a documented infection at baseline were significant independent risk factors for infectious complications. CONCLUSION: Compared with conventional chemotherapy, the incidence of infectious complications of venetoclax combined with decitabine or azacitidine significantly decreased. Pretreatment high leukemia burden and fever were independent risk factors for infections.

MNK1 inhibitor CGP57380 overcomes mTOR inhibitor-induced activation of eIF4E: the mechanism of synergic killing of human T-ALL cells.

Although the treatment of adult T-cell acute lymphoblastic leukemia (T-ALL) has been significantly improved, the heterogeneous genetic landscape of the disease often causes relapse. Aberrant activation of mammalian target of rapamycin (mTOR) pathway in T-ALL is responsible for treatment failure and relapse, suggesting that mTOR inhibition may represents a new therapeutic strategy. In this study, we investigated whether the mTOR complex 1 (mTORC1) inhibitor everolimus could be used as a therapeutic agent against human T-ALL. We showed that rapamycin and its analog RAD001 (everolimus) exerted only mild inhibition on the viability of Jurkat, CEM and Molt-4 cell lines (for everolimus the maximum inhibition was <40% at 100 nM), but greatly enhanced the phosphorylation of eIF4E, a downstream substrate of MAPK-interacting kinase (MNK) that was involved in promoting cell survival. Furthermore, we demonstrated in Jurkat cells that mTOR inhibitor-induced eIF4E phosphorylation was independent of insulin-like growth factor-1/insulin-like growth factor-1 receptor axis, but was secondary to mTOR inhibition. Then we examined the antileukemia effects of CGP57380, a MNK1 inhibitor, and we found that CGP57380 (4-16 µM) dose-dependently suppressed the expression of both phosphor-MNK1 and phosphor-eIF4E, thereby inhibiting downstream targets such as c-Myc and survivin in T-ALL cells. Importantly, CGP57380 produced a synergistic growth inhibitory effect with everolimus in T-ALL cells, and treatment with this targeted therapy overcame everolimus-induced eIF4E phosphorylation. In conclusion, our results suggest that dual-targeting of mTOR and MNK1/eIF4E signaling pathways may represent a novel therapeutic strategy for the treatment of human T-ALL.

[Apoptosis of acute myeloid leukemia HL-60 cells induced by CDK inhibitor SNS-032 and its molecular mechanisms].

OBJECTIVE: To investigate the effects of cycle-dependent kinase (CDK) inhibitor SNS-032 on apoptosis in human acute myeloid leukemia (AML) HL-60 cells and its molecular mechanisms. METHODS: Cultured AML HL-60 cells were treated with various concentrations of SNS-032. Cell apoptosis was determined with flow cytometry;cell viability was measured by MTT assay; the profiles of microRNA expression of HL-60 cells were analyzed by microRNA microarray;the protein expressions of JAK2/STAT3 pathway were detected by Western blotting. RESULTS: Apoptosis of AML HL-60 cells was induced by SNS-032; the rate of apoptosis was (5.9±1.7)%, (12.1±3.1)% and (59.4±3.6)% when HL-60 cells were treated with 0,100 and 200 nmol/L SNS-032. MicroRNA microarray analysis revealed that the levels of miR-30a, miR-183, miR-20b, miR-26b, miR-20a, miR-589, miR-107, miR-181a, miR-106a, miR-17 and miR-378c were down-regulated by SNS-032,whereas the levels of miR-320a and miR-H7* were up-regulated. Western blotting showed that SNS-032 strongly inhibited phosphorylation of STAT3 and protein expression of JAK2,C-MYC and MCL-1. CONCLUSION: CDK inhibitor SNS-032 can induce apoptosis of AML HL-60 cells, which is associated with the inhibition of MCL-1,C-MYC and JAK2/STAT3, and down-regulation of miR-17-92 family.

[Roles of microvesicles in tumor progress and its clinical application].

Microvesicles transport special proteins, micro RNA and DNA segments, which provides new access to intercellular communication. Tumor-derived membrane microvesicles (TMV) are involved in the tumor progress by transporting tumor-derived proteins, delivering microRNA to surrounding normal cells to alter their phenotype and promoting reverse transcription to interfere gene stability and to create tumor microenvironment. TMV also play crucial roles in tumor angiogenesis and matrix degradation, which facilitates malignant cell metastasis. TMVs are also involved in escaping immunological surveillance by intensifying the function of suppressor T cell and inducing apoptosis of cytotoxic T cells. On the other hand, microvesicles carry tumor antigens and can be used for development of tumor vaccines; some new vaccines such as AEX and DEX are under early clinical trials. Circulating microRNA and DNA segments in body fluid can be a new potential biomarker for cancer diagnosis and prognosis. Purification of microvesicles needs to be further improved, which is important for identification of microvesicles and their subtypes.

Synchronous diagnosis and treatment of acute myeloid leukemia and chronic lymphocytic leukemia: Two case reports.

BACKGROUND: The concurrence of acute myeloid leukemia (AML) and chronic lymphocytic leukemia (CLL) is rare. Previous reports of such cases have focused mainly on clinical diagnosis and characteristics, so the mechanism remains unclear, and therapy options have been poorly explored. CASE SUMMARY: Here, we report two cases of synchronous AML and CLL. Flow cytometry revealed two distinct abnormal cell populations (myeloblasts and lymphoid cells) according to scatter characteristics. CD5-positive B cell lymphoma with myeloid leukemia invasion was observed on lymph node biopsy. Chemotherapy regimens indicated for both AML and CLL were used in our patients, and our patients achieved complete response after chemotherapy. Next-generation sequencing of 88 genes was performed. CONCLUSION: We conclude that early mutation and dysregulation at the hematopoietic stem cell stage and the accumulation of multiple rearrangements may cause the concurrence of CLL and AML. The treatment of infection and combination therapy aimed at the CLL component are significant in the management of patients with concurrent CLL and AML.

[Comparison of the Curative Efficacy of Elderly Patients with High-Risk MDS and MDS-Transformed AML between Decitabine Combined with Low-Dose CEG Regimen and Decitabine Combined with Low-Dose CAG Regimen].

OBJECTIVE: To evaluate the efficacy of decitabine combined with low-dose CEG regimen (DCEG) and decitabine combined with low-dose CAG regimen (DCAG) in the treatment of elderly patients with MDS and MDS-transformed acute myeloid leukemia (AML). METHODS: A prospective study was conducted in 7 medical centers, 45 patients with MDS (≥ 60 years old) and MDS-transformed AML from October 2016 to January 2019 were enrolled, with the median age of 68.5 years old. The risk stratification of patients was poor or very poor, according to IPSS-R score. The treament results of decitabine combined with CEG and decitabine combined with CAG were compared. RESULTS: The comparison of the two regiem showed that the DCEG regimen had advantages on total effective rate (ORR, 86.4% vs 47.8%, respectively), overall survival time (OS) (10.0 months vs 6.0 months, respectively) and progression-free survival time (PFS) (9.0 months vs 3.0 months, respectively). About 50% of MDS patients treated by DCEG regimen achieved PR or CR, with a median OS of 31 months. Multivariate analysis showed that patients with PR or CR after induction therapy and DCEG regimen had longer survival time (31months). The incidence of bone marrow suppression, infection and treatment-related mortality rate were similar between the two groups. CONCLUSION: Decitabine combined with CEG regimen could improve the survival of patients with high-risk MDS and MDS-transformed AML. The conclusion of the reaserch needs to be validated by a larger prospective randomized clinical trial.

Salvage tigecycline in high risk febrile neutropenic patients with hematological malignancies: a prospective multicenter study.

The purpose of this prospective, multi-center study was to examine the efficacy and safety of tigecycline as empirical treatment in neutropenic patients with hematological malignancies who failed to respond to first-line antibiotics. A total of 125 patients with persistent fever (>72 h) despite first-line antibiotics received empirical treatment with tigecycline (loading dose of 100 mg, followed by 50 mg every 12 h). The use of other antimicrobial agents was not restricted. Treatment success rate was 68.0%. Subgroup analysis revealed a success rate of 73.1% in patients with pneumonia and 35.3% in patients with bacteremia. Toxicities were moderate with gastrointestinal symptoms being the main side effects. In conclusion, tigecycline-based antibacterial regimen was a justifiable empirical treatment in febrile neutropenic patients who failed to respond to first-line antibiotics except those with bacteremia. For patients with bacteremia, trials on higher-dose of tigecycline are needed.

[Study on unrelated donor allogeneic bone marrow transplantation with Bu-CY2 conditioning regimen for myelodysplastic syndrome].

OBJECTIVE: To evaluate the efficacy and safety of Bu-CY(2) conditioning regimen on allogeneic bone marrow transplantation (BMT) with unrelated donor for myelodysplastic syndrome. METHODS: Six patients received chemotherapy regimen of busulfan (Bu) and cyclophosphamide (CY) before allogeneic BMT (Bu 4 mg . kg(-1) . d(-1), -7 d - -4 d, CY 60 mg . kg(-1) . d(-1), -3 d - -2 d). Mycophenolate mofetil combined with cyclosporin A and methotrexate was used for prevention of acute graft-versus-host disease after transplantation. Lipo prostaglandin E(1)was used in prophylactic regimen for hepatic veno-occlusive disease. RESULT: Neutrophil count began to be higher than 0.5 x 10(9)/Lat the 18th day after BMT. Platelet count began to be higher than 20 x 10(9)/Lat the 21st day after BMT. Disease-free survival in the six patients was 27 months. CONCLUSION: Bu-CY(2) conditioning regimen on allogeneic bone marrow transplantation with unrelated donor is an effective therapy for patients with myelodysplastic syndrome.

[The clinical significance of angiogenesis in the bone marrow of acute leukemia patients].

OBJECTIVE: To study the angiogenesis in bone marrow and the level of vascular endothelial growth factor (VEGF) in bone marrow fluid from acute leukemia (AL) patients and to explore their clinical significance. METHODS: Microvessels in each bone marrow specimen section were counted by immunohistochemical identification of microvascular endothelial cells with anti-human von Willebrand factor under light microscopy in field 400 times. The VEGF level in bone marrow fluid was measured by ELISA. RESULTS: Microvessel counts in untreated AL patients (22.82/x 400 field) were significantly higher than those in normal controls (7.17/x 400 field) and in the bone marrow remission (BMR) AL patients (8.57/x 400 field) (P < 0.001, both), while the controls in the latter were higher than those in controls (P < 0.05). There was no difference in microvessel counts between untreated AL patients and relapse/refractory AL patients (21.83/x 400 field) (P > 0.05). In the untreated AL group, the microvessel counts showed difference neither between 23 ALL patients (23.09/x 400 field) and 43 ANLL patients (22.37/x 400 field) (P > 0.05), nor between patients with M(1 - 3) (22.91/x 400 field) and M(4 - 5) (21.46/x 400 field) the two subtypes of FAB (P > 0.05). There was a positive correlation between the microvessel counts and the percentage of blast cells in the bone marrow (r = 0.311, P < 0.01). The VEGF level in the bone marrow fluid in untreated AL patients (188.88 ng/L) was significantly higher than that in BMR AL patients (78.74 ng/L) and controls (79.52 ng/L) (P < 0.01), while the latter two groups had no difference between each other (P > 0.05). The VEGF level in the bone marrow fluid from ANLL group (270.12 ng/L) was enhanced significantly compared with that from ALL group (101.70 ng/L) (P < 0.01) and associated with the microvessel counts (r = 0.464, P < 0.05). CONCLUSION: Microvessel counts increased in the bone marrow in patients with different types of AL, suggesting that angiogenesis might play an important role in the pathology of AL. Testing the VEGF level in the bone marrow fluid from ANLL patients could reflect the degree of angiogenesis and disease condition.

Homoharringtonine induces apoptosis of endothelium and down-regulates VEGF expression of K562 cells.

Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. However, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry. The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner. Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.

[Itraconazole for secondary prophylaxis of invasive fungal infection in patients undergoing chemotherapy and stem cell transplantation].

OBJECTIVE: To evaluate the efficacy and safety of itraconazole for secondary prophylaxis of previous proven or probable invasive fungal infection (IFI) in patients undergoing chemotherapy or allogeneic hematopoietic stem cell transplantation (HSCT) in agranulocytosis state. METHODS: A phase IV prospective, open-label, multicenter trial was conducted to evaluate itraconazole (200 mg q12h intravenously d1-2, 200 mg/d) as secondary antifungal prophylaxis in patients (18-65 years old) undergoing chemotherapy or HSCT with previous proven or probable IFI. Itraconazole was started when patients' neutrophils＜1.5 × 109/L, and stopped when chemotherapy patients' neutrophils ＞0.5 × 109/L and stem cell transplant recipients' neutrophils＞1.0 × 109/L. The primary end-point of the study was the incidence of proven, probable or possible IFI. RESULTS: Seventy one patients from November 2008 to September 2010 were enrolled in the trial. The median duration of itraconazole prophylaxis was 14 (4-35) days. No patients died of drug-related toxicity within trial. Five cases occurred IFI during the trial. The cumulative incidence of invasive fungal disease was 7.0%. One patient was withdrawn from the study due to treatment-related adverse events (liver malfunction and severe phlebitis). CONCLUSION: Itraconazole appears to be safe and effective for secondary prophylaxis of systemic fungal infection after chemotherapy and allogeneic HSCT. The observed incidence of 7.0% is considerably lower than the relapse rate reported in historical controls, suggesting that itraconazole is a promising prophylactic agent in this population.

Clinical characteristics and outcome of isolated extramedullary relapse in acute leukemia after allogeneic stem cell transplantation: a single-center analysis.

Isolated extramedullary relapse (EMR) of acute leukemia (AL) is a rare occurrence. However, it appears to be more common after allogeneic stem cell transplantation (allo-SCT). To characterize what has been observed in isolated EMR, we investigated 287 consecutive AL patients (144 acute myeloid leukemia; 138 acute lymphocytic leukemia; 5 acute mixed-lineage leukemia) who underwent allo-SCT. Twelve cases experienced relapse at extramedullary sites without concomitant involvement of the bone marrow (BM). The onset to relapse after allo-SCT was longer in extramedullary sites than in the BM (median, 10 months versus 5.5 months). EMR sites varied widely and included the central nervous system, skin, bone, pelvis and breasts. Univariate analysis demonstrated that cytogenetic abnormalities were correlated significantly with the onset of isolated EMR (P=0.001). The prognosis for patients who develop EMR remained poor but was relatively better than that after BM relapse (overall survival, 10 versus 18 months). Compared with local or single therapy, patients treated with systemic treatment in combination with local treatment could yield a favorable prognosis. In conclusion, we observed a significant number of isolated cases of EMR in AL patients after allo-SCT, cytogenetic abnormalities were correlated significantly with the onset of isolated EMR. We found that intensive approaches combining local and systemic therapy could produce favorable responses which may cure a proportion of these patients.

Prognostic values of various clinical factors and genetic subtypes for diffuse large B-cell lymphoma patients: a retrospective analysis of 227 cases.

AIM: To analyze the significance of different clinical factors for prognostic prediction in diffuse large B-cell lymphoma (DLBCL) patients. METHODS: Two hundred and twenty-seven DLBCL patients were retrospectively reviewed. Patients were managed with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen or rituximab plus the CHOP (RCHOP) regimen. RESULTS: Lactate dehydrogenase (LDH), ß2- microglobulin (ß2-M), B symptoms, Ann Arbor stage and genetic subtypes were statistically relevant in predicting the prognosis of the overall survival (OS). In the CHOP group, the OS in patients with germinal center B-cell- like (GCB)(76.2%) was significantly higher than that of the non-GCB group (51.9%, P=0.032). With RCHOP management, there was no statistical difference in OS between the GCB (88.4%) and non-GCB groups (81.9%, P=0.288). CONCLUSION: Elevated LDH and ß2-M levels, positive B symptoms, Ann Arbor stage III/IV, and primary nodal lymphoma indicate an unfavorable prognosis of DLBCL patients. Patients with GCB-like DLBCL have a better prognosis than those with non-GCB when treated with the CHOP regimen. The RCHOP treatment with the addition of rituximab can improve the prognosis of patients with DLBCL.

Role of CT-guided percutaneous lung biopsy in diagnosis of pulmonary fungal infection in patients with hematologic diseases.

The goal of our study is to evaluate the efficiency and safety of CT-guided percutaneous lung biopsy for the diagnosis of pulmonary fungal infection in patients with hematologic disease. Medical records were retrospectively reviewed for 16 patients with hematologic diseases, who were initially suspected to have pulmonary fungal infection clinically and underwent further diagnostic methods including blood culture, sputum culture and percutaneous lung biopsy. Of the 16 patients, 10 were diagnosed fungal infection (8 aspergillus, 2 mold fungus), 4 chronic organizing pneumonitis, 1 tuberculosis, and 1 Pneumocystis carinii through histological examination after percutaneous lung biopsy. However, the results of blood culture and sputum culture were negative. CT-guided biopsy showed 100% overall accuracy and 62.5% (10/16) fungal infection rate. The biopsy-induced complications encountered were pneumothorax in 3/16 (18.75%) and hemoptysis in 1/16 (6.25%). No serious complication was found in this series. In conclusion, CT-guided percutaneous lung biopsy is an effective and safe method for the diagnosis of pulmonary fungal infection in patients with hematologic diseases.

Candida tropicalis arthritis in a patient with acute leukemia.

Candida arthritis in patient with hematological malignancy is rare. A case of Candida tropicalis arthritis of knee occurred in a patient with acute monocytic leukemia was reported during the recovery phase of post chemotherapy myelosuppression and agranulocytosis. The patient was diagnosed as Candida tropicalis arthritis of knee according to the Candida tropicalis isolated from the synovial fluid. Itraconazole and amphotericin B were intravenously injected for therapy for 4 - 5 weeks based on the susceptibility test in vitro, which showed better efficacy. But the arthritis relapsed at 4 - 6 weeks after the drug withdrawal. The curative effect was found in patient after treatment with fluconazole injection and articular cavity douching with amphotericin B for 8 weeks. In conclusion, although Candida arthritis in patient with hematological malignancy is rare, it still occurred in the patient with hypoimmunity. The treatment emphasis showed be placed on the full dosage and full treatment course of antifungal agent.

[The relationship between expression of the vascular endothelial growth factor and acute leukemia subtype].

OBJECTIVE: To investigate the relationship between expression of vascular endothelial growth factor (VEGF) and pathogenesis of acute leukemia (AL). METHODS: VEGF mRNA expression was analysed by using semi-quantitative RT-PCR technique. VEGF level of culture supernatant of the bone marrow mononuclear cell (BMMNC) was detected by ELISA. The influence of culture supernatant of the BMMNC on proliferation of human umbilical vein endothelial cell line huECV304 in vitro was determined by MTT assay. RESULTS: The median VEGF/beta-actin expression level of BMMNC in newly diagnosed untreated AL group was higher (0.86) than that in remission group (0.41) and normal control group (0.39) (P < 0.01, both), but was no difference from the relapse group (1.02, P > 0.05). Among the patients with newly diagnosed untreated AL, VEGF/beta-actin level in AML (1.03) was statistically higher than that in ALL (0.61) (P < 0.05). The VEGF level in 72 h culture supernatant of BMMNC was higher in newly diagnosed untreated AL group (91.48 ng/L) than in remission group (31.91 ng/L) and normal control group (28.71 ng/L) (P < 0.01). In ALL group (32.76 ng/L), the VEGF level of 72 h culture supernatant was much lower than that in AML group (173.49 ng/L) (P < 0.01). The proliferation of huECV304 cells after co-cultured with the 72 h culture supernatant of AML BMMNC with addition of anti-VEGF antibody was inhibited notably compared with culture supernatant alone (P < 0.01). However, no such result was found in ALL group (P > 0.05). CONCLUSION: The mRNA expression and secretion of VEGF in AML cells were higher than those in ALL cells. The regulators that participated angiogenesis were different in ALL and AML patients.

[Treatment of one case of adult chronic myelogenous leukemia by two units of unrelated umbilical cord blood transplantation].

To explore the hematopoietic reconstitution and transplantation-related complications of two units of unrelated umbilical cord blood combined transplantation for the treatment of adult hematologic malignancies, one adult patient with chronic myelogenous leukemia received two units of unrelated umbilical cord blood combined transplantation. The conditioning regimen was busulfan and cyclophosphamide (Bu-Cy). GVHD prophylaxis regimen consisted of mycophenolate mofetil (MMF), cyclosporine A (CsA) and methotrexate (MTX). The patient received total nucleated cells 4.63 x 10(7)/kg with CD34+ cells 8.34 x 10(5)/kg. Engraftment was documented by the analysis of short tandem repeat with polymerase chain reaction (STR-PCR). The results showed that the STR-PCR analysis for peripheral blood at day 31, 46 and 71 after transplantation suggested that one of two units of cord blood were completely engrafted. The ANC > 0.5 x 10(9)/L in the patient occurred at day 23, blood platelet counts > 20 x 10(9)/L at day 33 and > 50 x 10(9)/L at day 47. The Philadelphia chromosome and bcr/abl fusion gene of the patient also turned to negative after engraftment. Acute GVHD grade II occurred at day 13 and cured after treatment. It is concluded that umbilical cord blood can be used in adult hematopoietic stem cell transplantation. Two or more units umbilical cord blood combined transplantation might be the way to solve the problem of the low counts of nucleated cells when be used for adult.

[Treatment of childhood leukemia with unrelated donor allogeneic bone marrow transplantation].

OBJECTIVE: Allogeneic bone marrow transplantation has been established as a standard method for the treatment of a range of malignant and non-malignant hematologic diseases in children. Unfortunately, fewer than 30% of patients have a human leukocyte antigen (HLA)-matched sibling. Advances in our understanding of the HLA system and the development of large international donor registries encourage the increasing use of unrelated donors as an alternative source of stem cells. The purpose of this study was to evaluate the clinical efficacy and safety of unrelated donor allogeneic bone marrow transplantation (URD-BMT) for the treatment of childhood leukemia. METHODS: Six patients with leukemia received URD-BMT. Two of them suffered from chronic myeloid leukemia (CML), 3 suffered from acute lymphocytic leukemia (ALL) and 1 suffered from acute promyelocytic leukemia (APL) (CR2). All cases were facilitated by Tzu Chi Marrow Donor Registry (TCTMDR). The high resolution DNA test for classIand II was carried out in HLA typing of all donor-receiver pairs. HLA allele matched in three cases, mismatched with one locus in two cases and with two loci in one case. All patients were prepared with cyclophosphamide (CY) 60 mg/kg/day for 2 days (total dose 120 mg/kg) and busulfan (Bu) 1 mg/kg x 4/day for 4 days (total dose 16 mg/kg). Mycophenolate mofetil (MMF), CsA and MTX were given to prevent acute graft-versus-host-disease (aGVHD). CsA of 3 mg/kg/d was continuously given by i.v. infusion, and then 6mg/kg/d by oral. The blood CsA concentration was 200 - 300 ng/ml. MTX was given at the dosage of 15 mg/m(2) on d 1 and 10 mg/m(2) on d 3, 6,9 or 11. MMF was given at the dosage of 0.25 - 0.5 g/d from day 0 to day 120. Prostaglandin E1 was given to prevent the hepatic veno-occlusive disease (VOD), Ganciclovir was used to prevent CMV infection until the CMV antigenemia became negative. RESULTS: Analysis of DNA short tandem repeats showed total engraftment of donor marrow after transplantation in all cases. The median time when granulocyte exceeded 0.5 x 10(9)/L was 14.5 (13 - 18) days, platelets exceeded 20 x 10(9)/L was 16 (14 - 23) days. The acute GVHD grade II-IV occurred in 2 of 6 (33.3%) patients. There were 3 cases with chronic GVHD and none of them developed with the extensive chronic GVHD. All patients were alive in disease-free situation now with median follow-up 412 (187 - 1338) days. CONCLUSION: URD-BMT is an effective method for the treatment of childhood leukemia.