Invasive fungal infection in allogeneic hematopoietic stem cell transplant recipients: single center experiences of 12 years.

Invasive fungal infection (IFI) is a growing cause of morbidity and mortality among patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We retrospectively reviewed the records of 408 patients undergoing allo-HSCTs during the period November 1998 to December 2009, analyzed the incidence and risk factors of IFI, and examined the impact of IFI on overall survival. A total of 92 (22.5%) episodes suffered proven or probable IFI (4 patients were proven, 88 patients were probable). Candida was the most common pathogen for early IFI, and mold was the most frequent causative organism for late IFI. A prior history of IFI, human leukocyte antigen (HLA) mismatch, long-time neutropenia, and acute graft-versus-host-disease (GVHD) were risk factors for early IFI. A prior history of IFI, corticosteroid therapy, cytomegalovirus (CMV) disease, and chronic GVHD were risk factors for late IFI. IFI-related mortality was 53.26%. The 12-year overall survival (OS) rate for IFI was significantly lower than that of patients without IFI (41.9% vs. 63.6%, P<0.01).

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.

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.

Expression and clinical significance of antiapoptotic gene (survivin) in NB4 and acute promyelocytic leukemia cells.

To study survivin gene expression in APL cells and to explore its correlation with clinical manifestations. PML/RARα and survivin mRNA expression were analysed using RT-PCR. By treatment of ATRA, the survivin mRNA expression in NB4 cells gradually decreased with time and was almost undetectable in the 72th hour. Survivin was expressed in 67% of the 36 APL cases (de novo and relapse patients) with PML/RARα fusion gene expression. However, in 22 cases of remission stage patients without PML/RARα fusion gene expression, survivin was expressed in 36%. The survivin mRNA expression positive rate in de novo and relapse groups, and PML/RARα fusion gene L-type positive groups, was obviously higher than those in remission period groups and was significantly lower than those in acute leukemia groups. In 36 cases of de novo and relapse APL patients, all cases could obtain complete remission, irrespective of the survivin expression. APL patients expressed with survivin mRNA had DIC and serious infection (one patient died). The clinical symptom included slight skin or mucosa bleeding, fever, and asthenic for patients without the survivin mRNA expression. Later, two cases of APL patients with the survivin mRNA expression were treated by ATRA, induction differentiation sign in their peripheral blood and bone marrow figure was not obvious. It was concluded that the survive gene expression was lower in APL than those in any other types of leukemia, thus closely associated with clinical manifestation.

[Effect of APN/CD13 on bestatin enhancing all-trans-retinoic acid-inducing differentiation in NB4 cells].

This study was purposed to investigate the effect of aminopeptidase N/CD13 on bestatin enhancing all-trans-retinoic acid (ATRA)-inducing differentiation in NB4 cells. The nitroblue-tetrazolium (NBT) reduction assay was performed to determine the differentiation of NB4 cells, MR2 cells and primary APL blasts. The expression of P38 MAPK protein and the phosphorylation of P38 MAPK protein in NB4, MR2 and K562 cells were detected by Western blot. The results showed that pre-incubation with 5 µg/ml WM-15 blocked the enhancement effect of bestatin on differentiation of NB4 cells induced by ATRA. 5 µg/ml CD13 antibody WM-15 partly blocked the inhibition of bestatin on the phosphorylation of P38 MAPK in NB4 cells. 100 µg/ml bestatin inhibited the phosphorylation of P38 MAPK in NB4 cells and MR2 cells in a time-dependent manner. 100 µg/ml bestatin had no effect on the phosphorylation of P38 MAPK in K562 cells with low level of CD13. Bestatin could not restore the sensitivity to ATRA in ATRA-resistant primary APL blasts and MR2 cells. It is concluded that aminopeptidase N/CD13 inhibitor bestatin may enhance the differentiation-inducing activity of ATRA through inhibiting the phosphorylation of P38 MAPK in NB4 cells mediated by the cell surface APN/CD13.

[Arsenic trioxide enhances the effects of bortezomib, dexamethasone on multiple myeloma cell line KM3 in vitro.].

OBJECTIVE: To investigate the effect of bortezomib (Bor) alone or in combination with As(2)O(3) (ATO) and/or dexamethasone (DXM) on proliferation and apoptosis in KM3 human multiple myeloma cell line KM3. METHODS: KM3 cells were cultured with different concentrations of Bor and ATO and/or DXM in combination or Bor, ATO, DXM alone for different times. Cell proliferation was assayed by MTT assay, and IC(50) was calculated. Cell morphology was observed with light and electric microscopy. The agarose gel electrophoresis was used to evaluate DNA content, and the flow cytometry was used to exam Annexin V-FITC/PI stain. RESULTS: Bor, ATO and DXM inhibited KM3 cell proliferation in a time-and dose-dependent manner with the IC(50) of 0.27, 3.10 and 8.01 micromol/L, respectively. The inhibition rate of KM3 cells by Bor plus ATO and DXM was significantly higher than Bor plus ATO or DXM \[(34.51 +/- 0.51)% vs (25.39 +/- 0.90)% and (34.51 +/- 0.51)% vs (23.80 +/- 0.78)% respectively\]. Typical morphology for apoptosis and DNA ladder were observed in KM3 cell treated with 0.25 micromol/L Bor for 48 h, by Annexin V positivity. The apoptosis rate induced by Bor plus both ATO and DXM was higher than that induced by Bor plus DXM. CONCLUSION: Bor can inhibit the proliferation and induce apoptosis of KM3 cells. Bor enhances the inhibitory effect of ATO and DXM on the growth of KM3 cell. ATO enhances the apoptosis effects of Bor and DXM on KM3 cells.

Combined effects of bortezomib and daunorubicin on multiple myeloma cell KM3 in vitro.

The aim of this study was to investigate the combined effects of bortezomib (Bor) and daunorubicin (DNR) or each drug alone on proliferation of human multiple myeloma cell line KM3. KM3 cells were cultured with different concentrations of Bor and DNR, Bor or DNR alone for different times. The cell proliferation was analyzed by MTT assay, and the concentration of 50% growth inhibition (IC(50)) was calculated. The results indicated that both of Bor and DNR inhibited KM3 cell proliferation in dose dependent manner. The IC(50) of both drugs were 0.27 micromol/L and 0.16 micromol/L respectively. The inhibiting rate of Bor plus DNR on KM3 cells was much higher than that of Bor (p < 0.05). It is concluded that the Bor has synergistic inhibitory effect with DNR on the growth of KM3 cell in vitro.

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.

[Effects of soluble M-CSF receptor on differentiation of umbilical cord blood-derived myelomonocytic hematopoietic precursors in mesenchymal stem cell microenvironment].

OBJECTIVE: To investigate the effects of soluble M-CSF receptor (sMR) on proliferation and differentiation of hematopoietic precursors derived from umbilical cord blood in mesenchymal stem cell (MSC) microenvironment. METHOD: In group of cytokine (CK) + sMR, MSCs were used as feeder cells, mononuclear cells (MNCs) from cord blood were expanded in MSC microenvironment in presence of SCF, Flt3L, TPO, IL-6 and sMR. In CK control group, no sMR was added. MNC counting and colony forming cell (CFC) culture were performed at week 1, 2, 3 and 4. RESULTS: 1) The number of MNCs increased rapidly in both group CK and group CK + sMR (108.47 -fold and 120.67 -fold, respectively, P > 0.05). 2) CFC increased, peaked at week 3(38.1 x 10(3)) and declined rapidly at week 4(18.1 x 10(3)) in group CK, but still increased in group CK + sMR at week 4 (84 x 10(3)), the total number of CFC was higher in group CK + sMR than in group CK at week 3 and week 4 (P <0.01). 3) The erythroid CFC peaked at week 1 (5891.2 and 5635.6 for groups CK and CK + sMR, respectively), then dropped rapidly and to zero at week 3, in both group CK and group CK + sMR (P > 0. 05). 4) Myeloid CFC expanded continuously and peaked at week 3 (31.5 x 10(3)), then declined at week 4 (18.3 x 10(3)) in group CK; but still increased at week 4(80.8 x 10(3)) in group CK + sMR, being higher than that in group CK at week 3 and week 4 (P <0.01). CONCLUSION: sMR can inhibit the differentiation of cord blood hematopoietic precursors expanded in MSC microenvironment, but the inhibition exerts only on myelomonocytic but not on erythroid precursors.

[Experimental study of the enhancement effect of aminopeptidase N inhibitor ubenimex on the differentiation induction activity of all-trans-retinoic acid in acute promyelocytic leukemia cells and its mechanism].

OBJECTIVE: To investigate the effect of aminopeptidase N inhibitor ubenimex on differentiation induction of all-trans-retinoic acid (ATRA) in acute promyelocytic leukemia (APL) cells and its mechanism. METHODS: The expression of CD11b was analyzed by flow cytometry and nitroblue-tetrazolium (NBT) reduction assay was performed to determine the cell differentiation of APL cells. The expressions of c-Myc, ERK1/2, p38MAPK protein and the phosphorylation of ERK1/2, p38MAPK protein in NB4 cells were detected by Western blot assay. RESULTS: Ubenimex alone induced no significant changes in NBT reduction activity and CD11b expression but potentiated the differentiation induction activity of ATRA in APL cells. 100 microg/ml of ubenimex could enhance the NBT reduction activity induced by 10 nmol/L of ATRA, intensify the down-regulation of c-Myc protein expression and inhibit the phosphorylation of p38MAPK protein induced by 10 nmol/L of ATRA in NB4 cells. CONCLUSIONS: Ubenimex could potentiate ATRA induced differentiation in APL cells, which may be correlated with the inhibition of p38 MAPK protein phosphorylation and regulation of c-Myc protein expression.

[Expression level of TRF1 protein in human acute leukemia and its relationship with activity of telomerase].

The study was aimed to investigate the expression level of TRF1 protein in human acute leukemia and relationship between expression level of TRF1 protein and activity of telomerase. A quantitative Western blot technique was developed using anti-TRF1(33 - 277) monoclonal antibody and GST-TRF1 fusion protein as a standard to further determine the expression level of TRF1 protein in total proteins extracted from clinical specimens. 20 cases of acute leukemias were studied when 11 normal volunteer's bone marrow was used as control. The results showed that the expression level of TRF1 protein in normal bone marrow (2.217 +/- 0.461 microg/microl) was significantly higher than that in bone marrow of acute leukemia patients (0.754 +/- 0.343 microg/microl) (P < 0.01). There was no remarkable difference of expression level of TRF1 protein between ALL and ANLL (0.628 +/- 0.281 microg/microl vs 0.844 +/- 0.360 microg/microl, P > 0.05). After chemotherapy, TRF1 expression level of patients with complete remission raised (0.772 +/- 0.307 microg/microl vs 1.683 +/- 0.344 microg/microl, P < 0.01), but lower than that of normal (2.217 +/- 0.461 microg/microl, P < 0.01). TRF1 expression level of patients without complete remission was not remarkable different after chemotherapy (0.726 +/- 0.443 microg/microl vs 0.894 +/- 0.338 microg/microl, P > 0.05). TRF1 expression level of patients with complete remission was higher than that in patients without complete remession (1.683 +/- 0.344 microg/microl vs 0.894 +/- 0.338 microg/microl, P < 0.01). For all sample the telomerase activity was determined. It was confirmed that the activity of telomerase in normal bone marrow was lower than that in bone marrow of acute leukemia patients (0.125 +/- 0.078 microg/microl vs 0.765 +/- 0.284 microg/microl, P < 0.01). There was no significantly difference of expression level of TRF1 protein between ALL and ANLL (0.897 +/- 0.290 microg/microl vs 0.677 +/- 0.268 microg/microl, P > 0.05). After chemotherapy, telomerase activity of patients with complete remission reduced (0.393 +/- 0.125 microg/microl), but higher than that of normal (0.125 +/- 0.078 microg/microl, P < 0.01). It is concluded that expression level of TRF1 protein in AL patients is significantly decrese and associated with therapeutic efficaciousness and the activity of telomerase (P < 0.001).

[Impaired microfilament cytoskeleton rearrangement in cytomegalovirus infected cells].

OBJECTIVE: To investigate the effect of cytomegalovirus (CMV) infection on actin and microfilament in human embryo fibroblast cells (HF) and its relationship with CMV replication. METHODS: Cell morphology was observed after the infection of CMV. Western-blot was used to measure the expression levels of beta-actin, G-actin and F-actin proteins. CMV immediately early antigen (CMV IE) in HF cells was analyzed by indirect immunofluorescence assay. Microfilament alteration was determined by cytoskeleton fluorescence probe. RESULT: CMV IE was demonstrated in more than 95% of HF cells after infection, which was primarily located in nucleus. The shape of HF cells changed from thin shuttle like to round and thick ball like, even escaping from wall after infection by CMV. Compared with control group, the expression of G-actin protein increased at 24 h of CMV infection (0.941 +/-0.061 compared with 0.714 +/-0.119, P <0.05), then decreased at 72 h, 96 h respectively(0.218 +/-.035, 0.230 +/-0.055 compared with 0.714 +/-0.119, P <0.05). The levels of F-actin in infected cells gradually decreased at 24 h, 72 h and 96 h compared with control HF cells (0.256 +/-0.021, 0.127 +/-0.032, 0.026 +/-0.008 compared with 0.373 +/-0.050, P<0.05). In infected HF cells, microfilaments were found ruptured, arranged turbulently. Cells fused and fluorescence density of microfilament markedly reduced. CONCLUSION: Cytomegalovirus can induce alteration of actins and microfilament, which may be associated with its infection, replication and reactivity in host cells.

[Evaluation of interferon-gamma producing-cells using enzyme linked immunospot assay in mice model of acute graft versus host disease].

OBJECTIVE: To investigate IFN-gamma producing-cells (IFN-gamma PCs) in allogeneic mixed lymphocyte reaction (MLR) and acute graft versus host disease (aGVHD) model of mice. METHODS: Enzyme linked immunospot assay (ELISPOT) was applied to study IFN-gamma PCs in MHC mismatched mice spleen cell MLR and aGVHD model of mice. RESULT: IFN-gamma PCs increased significantly in MLR after allogeneic mice spleen cell stimulation. In the experimental mice aGVHD model, IFN-gamma PCs were significantly higher in the severe aGVHD group than those in the moderate aGVHD. In the moderate aGVHD group, mice with GVHD prophylaxis regimen demonstrated significantly lower level of IFN-gamma PCs, compared with those without prophylaxis. IFN-gamma PCs were significantly correlated with the GVHD clinical scores in the group with moderate aGVHD and prophylaxis regimen. CONCLUSION: ELISPOT is a fast, sensitive and specific approach to evaluate alloresponse in allogeneic mice MLR and IFN-gamma PCs are correlated closely with the severity of aGVHD and prophylaxis regimen in the MHC-mismatched mice model.

[Impaired microfilament cytoskeletal rearrangement in cytomegalovirus infected cells].

The objective of this study was to investigate the effect of cytomegalovirus (CMV) infection on actin and microfilament in human embryo fibroblast cells (HF) and to explore the possible relationship with CMV replication. The cell shape was observed by microscopy after the infection of CMV, RT-PCR assay was used to detect the mRNA expression of beta-actin gene, while Westen-blot was used to measure the level of beta-actin protein. CMV immediately early antigen (IE) in HF cells was analyzed by indirect immunofluorescence assay. Microfilament alteration was determined by cytoskeleton fluorescence probe. The results showed that CMV IE was observed in more than 95% of HF cells after infection, primarily located in nucleus. HF cells infected by CMV changed from thin shuttle shape to round and thick ball shape, even detached from wall. Beta-actin got a significant and gradual decreasing of mRNA level in time-dependent manner (P < 0.05). Compared with uninfected group, the expression of beta-actin protein decreased to (74.2 +/- 13.4)% at 96 hours after infection (P < 0.05). In infected HF cells, microfilaments were ruptured, arranged turbulently, as well as cells merged and fluorescence density of microfilament obviously reduced. It is concluded that cytomegalovirus can induce alteration of actin and microfilament, which may be helpful for CMV to infect, replicate and reactivate in host cells.

[Effect of aminopeptidase inhibitor on differentiation induction activity of all-trans retinoic acid in human acute promyelocytic leukemia NB4 cells and its mechanism].

This study was purposed to investigate whether aminopeptidase inhibitor, bestatin, can potentiate all-trans retinoic acid (ATRA)-inducing differentiation in NB4 cells, and to explore its mechanism. The NB4 cells were exposed to either bestatin and ATRA alone or in combination, the morphological changes of NB4 cells were observed by optical microscopy, the CD11b expression was measured by flow cytometry, the function of defferentiation cells was analyzed by nitroblue-tetrazolium (NBT) reduction assay, the mRNA expressions of c-myc and c-EBPepsilon in NB4 cells were detected by RT-PCR, the c-Myc protein expression was determined by Western blot. The results showed that treatment with bestatin alone induced no significant changes in morphology, NBT reduction activity and CD11b expression in NB4 cells. NB4 cells incubated with 10 nmol/L ATRA plus 100 microg/ml bestatin showed more morphologic feature of metamyelocyte and band neutrophil than ATRA alone treated cells. 100 microg/ml bestatin enhanced the NBT reduction activity in NB4 cells induced by various concentrations of ATRA (10, 20, 40 nmol/L). The effects of various concentrations of ATRA in combination with 100 microg/ml bestatin were statistically different from the effect of ATRA alone (P < 0.01). From 48 to 96 hours, 100 microg/ml bestatin time-dependently increased NBT reduction in NB4 cells induced by 10 nmol/L ATRA (P < 0.01). 10 nmol/L ATRA plus 100 microg/ml bestatin for 72 hours prominently elevated CD11b expression in NB4 cells as compared with ATRA alone treated NB4 cells (P < 0.01). There was a substantial decrease in c-myc mRNA levels when 100 microg/ml bestatin was added to 10 nmol/L ATRA (P < 0.05). Various concentrations (50, 75, 100 microg/ml) of bestatin combined with 10 nmol/L ATRA down-regulated the expression of c-Myc protein, which was negatively correlated with the NBT reduction activity of NB4 cells induced by 10 nmol/L ATRA alone or plus bestatin at various concentrations (r = -0.940, P = 0.017). However, 100 microg/ml bestatin plus 10 nmol/L ATRA could not induce any significant changes in the levels of c-EBPepsilon mRNA as compared with ATRA alone treated NB4 cells. It is concluded that an aminopeptidase inhibitor bestatin can potentiate ATRA-inducing differentiation of NB4 cells, possibly by down-regulating c-myc expression in synergy with ATRA.

[Relationship between the IFN-gamma producing cells specific for recipient and acute graft versus host disease].

OBJECTIVE: To study the relationship between the IFN-gamma producing cell specific for recipient (IFN-gamma-PCSR) in allogeneic stem cell transplantation (allo-HSCT) and acute graft versus host disease (aGVHD). METHODS: In 37 consecutive HLA-identical sibling allo-HSCT pairs, peripheral blood mononuclear cells (PBMNC) from donors before allo-HSCT and recipients after allo-HSCT were taken as responder cells (RC), and PBMNC from recipients before allo-HSCT as allogeneic stimulator cells (allo-SC) in mixed lymphocyte reaction (MLR). IFN-gamma-PCSR in PBMNC were assayed using enzyme linked immunospot assay (ELISPOT). RESULTS: Pretransplantation frequencies of IFN-gamma-PCSR in donor PBMNC were significantly higher in aGVHD group than in non-aGVHD group (P < 0.01) and IFN-gamma PCSRs (>or= 20/2 x 10(5)RC) were significantly associated with the occurrence of grade II-IV GVHD (P < 0.05). Compared with that before allo-HSCT, IFN-gamma PCSR in PBMNC of aGVHD patients was significantly increased (P < 0.05). When PBMNC from aGVHD patients reacted with donor PBMNC, the IFN-gamma PC was significantly lower than that with recipient PBMNC before allo-HSCT. Longitudinal analysis of IFN-gamma PCSR following allo-HSCT showed that compared with that in patients without aGVHD, the IFN-gamma PCSR were significantly higher in patients with that in aGVHD on day +14 (P < 0.01) and day +28 (P < 0.01), respectively. After immunosuppressive therapy for 7 days, IFN-gamma PC declined significantly (P < 0.05). CONCLUSION: The recipient-specific IFN-gamma PC is closely correlated with the allo-response during allo-HSCT and may be helpful for the prediction, diagnosis and monitoring of aGVHD.

[Expression of survivin gene in NB4 cell line and cells of acute promyelocytic leukemia and its anti-apoptosis and clinical significance].

The study was aimed to detect expression rate of survivin gene in APL cell and to explore the relationship between its expression and clinical manifestation. PML/RARalpha and survivin mRNA expression were analyzed by using reverse transcriptase polymerase chain reaction (RT-PCR) technique. The results showed: (1) the survivin gene expression was detected in NB4 cell line. By treatment with ATRA, survivin mRNA expression in NB4 cell gradually decreased along with time delay and almost could not be detected at the 72th hour. (2) the positive and negative rate of survivin mRNA expression was 67% and 33% respectively, while in all 36 cases of de novo and relapse APL patients, the PML/RAR(alpha) fusion gene expression was positive. In 22 cases at remission stage, the PML/RARalpha fusion gene expression was negative, and the positive and negative rate of survivin mRNA expression was 36% and 64% respectively. The survivin mRNA expression positive rates in the de novo group, relapse group and PML/RARalpha fusion gene L-type positive group were obviously higher than those in remission period group (P < 0.05) and were significantly lower than those in acute leukemia group (P < 0.05, < 0.001). (3) whether the survivin mRNA expression was positive or negative in 36 cases of de novo and relapse APL patients, all the 36 cases could obtain complete remission. 4 APL patients with positive expression of survivin mRNA had DIC and serious infection (one patient died). The clinical symptom showed slight skin or mucosa bleeding, fever and asthenic in the patients with negative expression of survivin mRNA. When 2 APL patients with positive expression of survivin mRNA had been treated with ATRA, induction differentiation sign in their peripheral blood and bone marrow figures was not obvious. It is concluded that the survivin gene positive expression rate is lower in acute promyelocytic leukemia than that in any other types of leukemia and is related to clinical manifestation.

[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.

Homoharringtonine-induced apoptosis of human leukemia HL-60 cells is associated with down-regulation of telomerase.

Homoharringtonine (HHT), first isolated from the Chinese evergreen Cephalotaxus Harringtonia, has been shown inhibiting activity in leukemia in initial studies in China and in later studies in the US, but the detailed mechanism of action is still unclear. The goal of the experiments shown here is to explore the effect of HHT on the telomerase activity and apoptosis of human leukemia HL-60 cells. The telomerase activity of HL-60 cells was examined by the telomeric repeat amplification protocol (TRAP)--an enzyme-linked immunosorbent assay (ELISA). Apoptosis was analyzed by morphological observation, DNA agarose gel electrophoresis, flow cytometry (FCM), and TdT-mediated dUTP-biotin nick end labeling (TUNEL). After treatment with HHT at 5-500 microg/l for 48 hours, the level of telomerase activity in HL-60 cells decreased in a dose-and time-dependent manner. Simultaneously, HL-60 cells underwent apoptosis. In conclusion, our data suggest that HHT can inhibit the telomerase content of HL-60 cells effectively and induce apoptosis.