FGFC1 Exhibits Anti-Cancer Activity via Inhibiting NF-κB Signaling Pathway in EGFR-Mutant NSCLC Cells.

FGFC1, an active compound isolated from the culture of marine fungi Stachybotrys longispora FG216, elicits fibrinolytic, anti-oxidative, and anti-inflammatory activity. We have previously reported that FGFC1 inhibited the proliferation, migration, and invasion of the non-small cell lung cancer (NSCLC) cells in vitro. However, the precise mechanisms of FGFC1 on NSCLC and its anti-cancer activity in vivo remains unclear. Hence, this study was focused to investigate the effects and regulatory mechanisms of FGFC1 on two NSCLC cell lines, EGFR-mutant PC9 (ex19del) and EGFR wild-type H1299. Results suggested that FGFC1 significantly inhibited proliferation, colony formation, as well as triggered G0/G1 arrest and apoptosis of PC9 cells in a dose- and time-dependent manner, but no obvious inhibitory effects were observed in H1299 cells. Subsequently, transcriptome analysis revealed that FGFC1 significantly down-regulated 28 genes related to the NF-κB pathway, including IL-6, TNF-α, and ICAM-1 in the PC9 cells. We further confirmed that FGFC1 decreased the expression of protein p-IKKα/ß, p-p65, p-IκB, IL-6, and TNF-α. Moreover, NF-κB inhibitor PDTC could strengthen the effects of FGFC1 on the expression of CDK4, Cyclin D1, cleaved-PARP-1, and cleaved-caspase-3 proteins, suggesting that the NF-κB pathway plays a major role in FGFC1-induced cell cycle arrest and apoptosis. Correspondingly, the nuclear translocation of p-p65 was also suppressed by FGFC1 in PC9 cells. Finally, the intraperitoneal injection of FGFC1 remarkably inhibited PC9 xenograft growth and decreased the expression of Ki-67, p-p65, IL-6, and TNF-α in tumors. Our results indicated that FGFC1 exerted anti-cancer activity in PC9 cells via inhibiting the NF-κB signaling pathway, providing a possibility for FGFC1 to be used as a lead compound for the treatment of NSCLC in the future.

Design, synthesis and biological evaluation of sulfonamides inhibitors of XPO1 displaying activity against multiple myeloma cells.

Multiple myeloma (MM) is a highly malignant hematologic cancer that occurs when an atypical plasma cell develops in the bone marrow and reproduces quickly. Despite varies of new drugs have been developed or under clinic trial, MM is still essentially incurable, while XPO1 inhibition has emerged as a promising therapeutic strategy in the treatment of MM. Using the second-generation XPO1 inhibitor KPT-8602 as the lead compound, structure-based optimization provided D4 with high anti-proliferation efficacy (IC50 = 24 nM in MM.1S). In addition, the treatment with D4 significantly induced MM.1S cell cycle arrested and cell apoptosis, which was confirmed as on-target effect by immunofluorescence microscopy and competitive binding assay. Moreover, D4 displayed good metabolic stability over rat plasma and liver microsomes, as well as good pharmacokinetic profile on SD rat model with high drug exposure and decent bioavailability by oral gavage. All these good properties of D4 pave the way for further drug development and clinical application.

FGFC1 Selectively Inhibits Erlotinib-Resistant Non-Small Cell Lung Cancer via Elevation of ROS Mediated by the EGFR/PI3K/Akt/mTOR Pathway.

Non-small cell lung cancer (NSCLC) is one of the most common malignancies in the world. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have been used as a first-line treatment for patients harboring with EGFR mutations in advanced NSCLC. Nevertheless, the drug resistance after continuous and long-term chemotherapies considerably limits its clinical efficacy. Therefore, it is of great importance to develop new chemotherapeutic agents and treatment strategies to conquer the drug resistance. FGFC1 (Fungi fibrinolytic compound 1), a type of bisindole alkaloid from a metabolite of the rare marine fungi Starchbotrys longispora. FG216, has exhibited excellent fibrinolytic and anti-inflammatory activity. However, the potent efficacy of FGFC1 in human cancer therapy requires further study. Herein, we demonstrated that FGFC1 selectively suppressed the growth of NSCLC cells with EGFR mutation. Mechanistically, FGFC1 treatment significantly induced the apoptosis of erlotinib-resistant NSCLC cells H1975 in a dose-dependent manner, which was proved to be mediated by mitochondrial dysfunction and elevated accumulation of intracellular reactive oxygen species (ROS). Scavenging ROS not only alleviated FGFC1-induced apoptosis but also relieved the decrease of phospho-Akt. We further confirmed that FGFC1 significantly decreased the phosphorylation of protein EGFR, phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) in H1975 cells. Notably, PI3K inhibitor (LY294002) could promote the accumulation of ROS and the expression levels of apoptosis-related proteins induced by FGFC1. Molecular dynamics simulations indicated that FGFC1 can inhibit EGFR and its downstream PI3K/Akt/mTOR pathway through directly binding to EGFR, which displayed a much higher binding affinity to EGFRT790M/L858R than EGFRWT. Additionally, FGFC1 treatment also inhibited the migration and invasion of H1975 cells. Finally, FGFC1 effectively inhibited tumor growth in the nude mice xenograft model of NSCLC. Taken together, our results indicate that FGFC1 may be a potential candidate for erlotinib-resistant NSCLC therapy.

[The clinical evaluation of preemptive treatment of cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To retrospectively analyze the effect of preemptive treatment on cytomegalovirus (CMV) infection in patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: The data of one hundred and three patients who underwent allo-HSCT with preemptive treatment to prevent CMV associated diseases were retrospectively analyzed. Fluorescence quantitative PCR was used to detect CMV-DNA. The incidences of CMV viremia and CMV associated diseases were analyzed. RESULTS: CMV viremia was confirmed 63 times in 51 of the 103 patients. The incidence of CMV viremia was 49.5% and the median time of onset was 40 days after transplantation. All the patients with CMV viremia received preemptive antiviral therapy and 19 of them developed CMV associated diseases, including 14 hemorrhagic cystitis, 3 CMV associated pneumonia and 2 CMV associated enteritis. The total incidence of CMV associated diseases was 18.4%. After treatment with ganciclovir and/or foscarnet, 60 of the 63 times of CMV viremia disappeared. One patient was not included in the analysis because he died of intracranial hemorrhage and GVHD only 3 days after the treatment. The total response rate was 96.8% (60/62). The remaining two cases who did not respond to treatment died of CMV associated pneumonia in combination with acute GVHD. The direct mortality rate of CMV infection was 1.9% (2/103). CONCLUSION: The incidences of CMV viremia and CMV associated diseases do not increase in patients receiving preemptive therapy as compared with those receiving prophylaxis therapy. Preemptive treatment can not only prevent the progression of CMV viremia to CMV associated diseases in majority of the cases but also control CMV associated diseases effectively.

XIAP is upregulated in HL-60 cells cocultured with stromal cells by direct cell contact.

Apoptosis resistance is an important mechanisms of drug resistance mediated by bone marrow stromal cells (BMSCs). BMSCs influence tumor cells survival through several mechanisms including direct cell-cell contact and the effects of soluble factors. In this research we investigated the role of X-linked inhibitor of apoptosis protein (XIAP) in the apoptosis resistance mediated by stromal cells in HL-60 cells and the signaling pathway involved. We found that bone marrow stromal-derived soluble factors and direct cell contact both prevented apoptosis of HL-60 cells. XIAP is upregulated by direct cell contact but not by soluble factors. Phosphatidylinositol 3-kinase (PI3K) and Akt were activated and LY294002 downregulated XIAP and increased apoptosis in HL-60 cells co-cultured with BMSCs. The results indicated that PI3K/Akt/XIAP is an important pathway involved in the apoptosis resistance of HL-60 cells co-cultured with BMSCs by direct cell contact. Inhibition of this signaling pathway may provide a new therapeutic strategy for acute myeloid leukemia treatment.

Simultaneous suppression of multidrug resistance and antiapoptotic cellular defense induces apoptosis in chemoresistant human acute myeloid leukemia cells.

The emergence of acquired drug resistance is a major hurdle in the successful treatment of leukemia. Researches indicated that the main mechanisms of most cancers included so-called "pump" and "nonpump" resistance. We studied the mechanisms involved in the drug resistance of HL-60/ADR and found that its drug resistance was associated with the simultaneous overexpression of XIAP and MRP. We compared the reversal effects of XIAP and MRP ASO used in combination and separately. Reverse transcription-PCR and Western blot were applied to examine the changes of mRNA and protein levels, respectively. The results showed that XIAP and MRP ASO used separately could down-regulate the expression of XIAP and MRP in HL-60/ADR cells, respectively. XIAP and MRP ASO used in combination did not enhance the inhibition expression of XIAP and MRP of HL-60/ADR cells. The apoptosis of co-transfection group was significantly higher than XIAP ASO (P<0.05). The cytotoxicity was determined by MTT cell viability/proliferation assay. When used in combination the sensitivity of HL-60/ADR cells to DNR was increased significantly compared with XIAP or MRP ASO used separately (P<0.05). The results indicated that both XIAP and MRP were involved in the drug resistance mechanisms of HL-60/ADR cells. The sensitivity to DNR could be enhanced significantly when XIAP and MRP ASO used in combination.

[A modified cytogenetic study for multiple myeloma].

OBJECTIVE: To evaluate the effect of modified culture method used to cytogenetic analysis and the clinically significance of chromosomal abnormalities to multiple myeloma (MM). METHODS: Mononuclear cells were isolated from bone marrow aspirate of 20 MM patients; and then cultured for 3 days without any cytokines, and 6 days in the presence of IL-6 (10 ng/mL) and GM-CSF (30 ng/mL) before RHG banding analysis; the remained part of aspirates were treated directly. Eight cases of iron deficiency anemia were taken as control. RESULTS: The experiment was failure in 2 cases because of blood clot, and another 2 cases could be analyzed only by direct method due to inadequate cells. The karyotype abnormalities were found from 4 cases of 16 available patients. Of them, three cases had complex karyotypes. The abnormalities were detected after 6 days culture with addition of cytokines. No abnormalities were detected from those groups of directly analysis and 3 day culture. Meantime, the clinical data showed that the patients with cytogenetic abnormalities were in stage III, and had a high percentage of MM cells (25%-56%) in their bone marrow, and also poor responses to prior chemotherapy. No cytogenetic abnormalities were found from control individuals in all groups. CONCLUSION: Extended culture in the presence of cytokines could improve the efficiency of cytogenetic analysis to MM. Complex karyotype was common cytogenetic abnormalities in MM patients with poor response to chemotherapy.

[Partial deletion of chromosome 13 long arm in multiple myeloma and its clinical significance].

OBJECTIVE: To explore the specific locus deletion of the long arm of chromosome 13 and its relationship with the clinical behavior and prognosis of multiple myeloma (MM). METHODS: FISH analysis was performed on bone marrow smears from 68 patients with MM to study the deletion of Rb-1 gene and locus 13q14.3 on chromosome 13. The statistic value of its effect on clinical features were determined. RESULTS: 35 out of the 68 (51%) cases were found with deletion of chromosome 13; deletion of Rb-1 gene were found in 29 (43%) cases; deletion of locus 13q14.3 were found in 23 out of 44 (52%) cases; the analysis results were same in 66% of the cases (29/44) with the above two probes. Chi-square test showed that partial deletion of chromosome 13 was associated with clinical behavior, early chemotherapy response and 1 year survival. CONCLUSION: Deletion of Rb-1 gene and locus 13q14.3 were both common cytogenetic changes in MM patients with effect on the biological behavior of the disease.

[An analysis of leukocyte subsets chimerism following allogeneic peripheral blood stem cell transplantation].

OBJECTIVE: To analyse the relationship of T lymphocyte and granulocyte chimerism following allogeneic peripheral blood cell transplantation and the occurrence of relapse, graft failure and graft versus host disease. METHODS: 21 patients underwent allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Fluorescence-activated cell sorter (FACS) sorted CD3+ T lymphocytes and CD15+ granulocyte from peripheral blood of all the patients were analyzed for short tandem repeats in 7 days interval for 1 month starting from the day of PBSCT, then 1 month interval for 6 months, and then 3 months interval to the end of one year. RESULTS: Chimerism of granulocyte was higher than T lymphocyte on day 7 posttransplant in 4 patients given myeloablative conditioning. The median donor chimerism of granulocyte and T lymphocyte was 95% and 55% respectively. The other 17 patients had higher chimerism of T lymphocyte than granulocyte on day 7, which was 60% (15%-76%) and 0% (0%-40%) respectively. 20 patients reached complete donor chimerism (CDC) on day 21 (14-102 days) for T lymphocyte and on day 14 for granulocyte, except one relapsed on day 28. Seven patients had decreasing mixed chimerism when disease relapsed or graft failure occurred. T cell donor chimerism decreased earlier than myeloid cells, however, bone marrow sample and granulocyte still remained in complete donor chimerism or stable mixed chimerism, bone marrow smear showed normal at the same time. CONCLUSION: Blood leukocyte subset chimerism analysis, especially T cell chimerism analysis may provide earlier information of engraftment, relapse and graft failure than blood and bone marrow samples, therefore immunomodulatory therapies may be given to recipients earlier and overall survival may be improved.

Donor Chimerism of B Cells and Nature Killer Cells Provides Useful Information to Predict Hematologic Relapse following Allogeneic Hematopoietic Stem Cell Transplantation.

In this study we investigated the correlation between donor chimerism status and disease relapse following allogeneic hematopoietic stem cell transplantation (allo-HSCT). The chimerism of Fluorescence-activated cell sorter (FACS) sorted CD3+T lymphocytes of 153 cases, CD56+CD16+NK lymphocytes of 153 cases and CD19+B lymphocytes of 31 cases with acute B lymphoblastic leukemia (B-ALL) was analyzed post-transplant utilizing polymerase chain reaction amplification of short tandem repeats (PCR-STR). A total of 33 patients (33/153, 21.6%) had recurrent disease. The positive predictive values of declining donor chimerism for hematologic and isolated extramedullary relapse were 58.8% and 10% (P=0.018, Chi-Square). The positive predictive values of declining donor chimerism in BMB, BMT, BMNK and PBB for hematologic relapse were 11.6%, 0%, 0% and 0% under close monitoring in patients with B-ALL. Only the donor chimerism in BMB significantly decreased in the group with hematologic relapse as compared with the group without hematologic relapse (P=0.00, Independent-samples T test) in patients with B-ALL. The median drop of donor chimerism in PBT, BMT, PBNK and BMNK were 0%, 0%, 5.9% and 2.8% one or two weeks prior to hematologic relapse in patients with non-B-ALL. The donor chimerism in PBNK significantly decreased prior to hematologic relapse in the group with hematologic relapse as compared with the group without hematologic relapse (P=0.022, Independent-samples T test).These data suggest donor chimerism of BMB can be used to predict the occurrence of hematologic relapse in patients with B-ALL. Donor chimerism decrease in PBNK was associated with a somewhat increased risk of hematologic relapse in patients with non-B-ALL. Therefore, our results reveal a more effective path to individually predict for hematologic relapse by dynamic monitoring different cell lineages in different disease.

Allogeneic peripheral blood stem cell transplantation in the treatment of severe aplastic anemia and severe infection.

OBJECTIVE: To investigate the efficacy of allogeneic peripheral blood stem cell transplantation (PBSCT) in the treatment of severe aplastic anemia (SAA) and severe infection. METHODS: A patient with SAA and pseudomonas aeruginosa septicemia was treated with PBSCT from an HLA-identical sibling with cyclophosphamide (CY) and total body irradiation (TBI) for conditioning. The patient was infused with 20.3 x 10(8)/kg mononuclear cells including 61.0 x 10(6)/kg CD34(+) cells following the conditioning regimen. RESULTS: Twelve days after PBSCT, the absolute neutrophil count (ANC) of 1.0 x 10(9)/L was achieved, with platelet count > 50 x 10(9)/L at twenty days. The donor origin of engraftment was confirmed by polymerase chain reaction (PCR) analysis of short tandem repeats at the end of the first, sixth and twelfth month. The patient's body temperature dropped to normal level when her ANC reached 0.5 x 10(9)/L on day 10, and the bacterial culture of blood sample became negative subsequently. Symptoms and signs of acute or chronic graft versus host disease (GVHD) were not observed in 30 months after PBSCT. CONCLUSIONS: Hematopoiesis was reconstituted shortly after PBSCT. The combination of CY and TBI and the infusion of sufficient peripheral blood stem cells may contribute to the successful engraftment. PBSCT may be considered as the first choice when hematopoietic stem cell transplantation is needed for SAA patients complicated with severe infection.

Chimerism status is correlated to acute graft-versus-host disease after allogeneic stem cell transplantation.

To evaluate the correlation between chimerism status and acute graft-versus-host disease (aGVHD) following allogeneic hematopoietic stem cell transplantation. Chimerism of peripheral blood of 124 patients was monitored at regular intervals post-transplant. The chimerism of 124 post-transplant cases of CD3(+)T lymphocytes, 107 cases of CD3(-)CD56(+)CD16(+)NK lymphocytes, 49 cases of CD15(+) granulocytes, and 27 cases of CD19(+)B lymphocytes sorted by fluorescence-activated cell sorter were analyzed by polymerase chain reaction amplification of short tandem repeats. Differences were found in the time between establishment of full donor T-cell chimerism and the occurrence of aGVHD (P = 0.035, two related samples test). Patients with ≥69 % donor chimerism on day +7 in T-cells had higher rates of aGVHD. This study may provide a rational basis for treatment with adoptive immunotherapy at an earlier time, such as day 7 after SCT, than at present to prevent aGVHD.

JAK2 V617F positive essential thrombocythemia developing in a patient with CD5⁻ chronic lymphocytic leukemia.

Coexistence of chronic lymphocytic leukemia (CLL) and essential thrombocythemia (ET) in a patient is extremely rare, with only 10 cases reported thus far in literature. This paper describes a 94-year-old male having atypical B-CLL with CD5⁻ (CD5⁻) phenotype and ET. In this patient, we performed interphase fluorescence in situ hybridization (FISH) analysis which revealed 13q14.3 deletion in 31% of B-lymphocyte nuclei and RB1 deletion in 27% of B-lymphocyte nuclei, but not in neutrophils and T-lymphocytes. Furthermore, we identified JAK2 V617F mutation in the peripheral blood nucleated cells and neutrophils, but not in the B- and T-lymphocyte populations. Therefore, it was concluded that the occurrence of CD5− B-CLL and ET in this patient was pathogenically independent.

[Comparison of STR-PCR and FISH value for monitoring chimerism after sex-mismatched allogeneic hematopoietic stem cell transplantation].

This study was purposed to compare the significance of multiplex short tandem repeat polymerase chain reaction (STR-PCR) and fluorescent in situ hybridization (FISH) for monitoring chimerism after sex-mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT). The chimerism of bone marrow or peripheral blood cells from 38 patients was analyzed by STR-PCR and FISH on days 14, 28 and at 3 months after allo-HSCT. The results indicated that on day 14, the complete chimerism (CC) was detected in 14 of 30 cases by STR-PCR and in 8 of 30 cases by FISH (p > 0.05). On day 28, the CC was detected in 26 of 31 cases by STR-PCR and in 15 of 31 cases by FISH (p < 0.01). At 3 months, the CC was observed in 22 of 24 cases by STR-PCR and 17 of 24 cases by FISH (p > 0.05). 14 cases were found to have a graft rejection or relapse among 28 cases which were continuously monitored more than 3 months post the transplants. Donor cell decrease in 9 of 14 cases was proved by FISH alone. It is concluded that FISH is more sensitive than STR-PCR in early monitoring chimerism status of post-transplant and in predicting graft rejection or disease relapse.

[The role of FDG-PET in staging of lymphoma and evaluation of therapeutic efficiency].

OBJECTIVE: To evaluate the application of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) to the staging and detecting residual masses of lymphoma. METHODS: The clinical data of 179 patients with lymphoma were analyzed retrospectively. The results of FDG-PET, computed tomography (CT) and bone marrow biopsy (BMB) were compared for detection of lymph node/extranodal lymphoid tissue and bone marrow infiltration. Therapeutic efficiency was assessed by International Workshop Criteria (IWC) and Revised Integrated International Workshop Criteria (IWC + PET). RESULTS: In the detection of 286 disease focuses in 98 patients before chemotherapy, the sensitivities of FDG-PET and CT were 73% and 70% (P < 0.01) in detecting nodal focus,and 87% and 45% (P < 0.01) in detecting extranodal lymphoma respectively. In detection of 104 lesions in 81 patients after chemotherapy,the sensitivities of FDG-PET and CT were 81% and 55% respectively (P < 0.01), and the specificities were 68% and 33%, respectively (P < 0.01) in detecting residual masses. According to IWC criteria, 33 patients achieved complete response/unconfirmed complete response (CR/CRu) , and 8 (24%) relapsed. Patients with PET-positive residual masses had a relapse rate of 40%, whereas only 21% of those with no such masses relapsed. Based on IWC + PET criteria, 25 patients achieved CR, with a relapse rate of 20%. Both FDG-PET and BMB produced positive results in 133/179 (74%) patients. Twenty-two patients with positive FDG-PET results were not detected by BMB. The sensitivities and specificities of FDG-PET for BM infiltration were 52% and 83%, respectively. CONCLUSIONS: FDG-PET is a high sensitive and specific technique in staging and detecting residual masses of lymphoma.

The association of up-regulation of X-linked inhibitor of apoptosis protein with cell adhesion-mediated drug resistance in U937 cells.

An increasing body of evidence indicates that environmental factors may contribute to the drug resistance of acute myeloid leukaemia (AML). CAM-DR (cell adhesion-mediated drug resistance) is a reversible, de novo drug resistance induced by adhesion of tumour cell lines to fibronectin (FN). Adhesion was demonstrated to directly regulate the apoptotic machinery. And it was observed in previous studies that high levels of X-linked inhibitor of apoptosis protein (XIAP) were related to resistance to chemotherapeutics in many cancer cell lines. However, whether XIAP is relevant to CAM-DR of AML cells is unknown. In this report, we demonstrated that the mRNA and protein levels of XIAP were increased by 96.15% and 120.92%, respectively in U937 cells cocultured with FN as compared with controls. Antisense oligonucleotides targeting XIAP down-regulated the expression of XIAP and sensitized U937 cells to daunorubicin. In addition, we investigated the signalling pathway involved in the upregulation of XIAP. The levels of phosphorylated Akt (Ser473) were elevated in U937/FN cells and the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 suppressed XIAP expression and restored the chemosensitivity to daunorubicin. Our findings suggested that adhesion-dependent activation of the PI3K/Akt/XIAP pathway may be one of the factors involved in the CAM-DR of U937 cells. Targeting this pathway may be a useful approach to improve the therapeutic responsiveness of leukaemia cells.

[Allogeneic hematopoietic stem cell transplantation following reduced intensity conditioning regimen for treatment of refractory leukemia].

OBJECTIVE: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) following reduced intensity conditioning (RIC) regimen for treatment of refractory leukemia. METHODS: Twenty patients with refractory leukemia received allo-HSCT following RIC regimen consisting of fludarabine plus small or moderate dose total body irradiation (TBI). Graft versus host disease (GVHD) prophylaxis was CsA plus mycophenolate mofetil (MMF) or short-term MTX, or these three drugs combination; CD25 monoclone antibody(McAb) and ATG were also used in some of the patients. RESULTS: Seventeen patients engrafted successfully, the median time for ANC > 0.5 x 10(9)/L was 13 (11 - 17) days, and for BPC > 50 x 10(9)/L 19 (12 -42) days. Detected by short tandem repeat (STR)-PCR, complete donor chimerism was confirmed in 16 patients with a median of 14 (7 -35) days. The incidence of acute and chronic GVHD was 47.1% (8/17) and 38.5% (5/13) respectively. The transplant related mortality (TRM) was 25.0% (5/20), mainly from graft failure, intracranial hemorrhage and severe infection. Up to now, 7 patients relapsed and 9 were alive with leukemia free. The overall survival (OS) at 2 year was (35. 3 +/- 14.2)% for all patients and (52.5 +/- 18.6)% for acute non-lymphocytic leukemia (ANLL) patients. CONCLUSION: Allo-HSCT following fludarabine and TBI based RIC regimen can be used for treatment of refractory leukemia with well tolerance and low TRM and there is a better prognosis for ANLL patients than that for acute lymphocytic leukemia patients.

[Inhibitory effect of Rnai on AML1 -ETO fusion gene expression in leukemia cells].

OBJECTIVE: By inhibiting AML1 -ETO fusion gene expression in Kasumi-1 cells with RNAi, to investigate the changes in cell proliferation and cell cycle. METHODS: The small interference RNAs (siRNAs) specifically targeting the AML1 -ETO fusion gene were synthesized in vitro and transfected into Kasumi-1 cells by electroporation, the non-specific siRNAs transfected cells were taken as control. EGFP plasmid was transfected into Kasumi-1 cell and the transfection efficiency was detected by FCM. Inhibitory effect of siRNAs were detected by real-time RT-PCR and Western blots. Cell proliferation was measured by CCK-8 assay. DNA content was detected by PI assay. RESULTS: The transfection efficiency was 44.5%. The AML1 -ETO specific siRNAs inhibited AML1 -ETO expression at both mRNA and protein levels. The cell proliferation rate in siRNAs treated group was lower than that in control group 72 h after transfection [(47.90 +/- 0.02)% vs (66.90 +/- 0.08)% , P < 0.05]. The cell cycle was blocked at G1 phase 72 h after siRNAs treatment, the cell proportion in G1 phase being 38.3% and 31.6% in control group, while in G2/M phase being 1.8% and 2.4% respectively. CONCLUSIONS: The synthesized siRNAs can inhibit AML1 -ETO fusion gene expression. AML1 -ETO specific siRNA induced the decline of AML1 -ETO fusion protein in Kasumi-1 cell, and then caused the cell cycle blocked in G1 stage and eventually inhibited the cell proliferation.

[Distribution of abnormal cell clone with deletion of chromosome 20q in marrow cell lineages and apoptosis cells in myelodysplastic syndrome].

This study was aimed to investigate the distribution of abnormal clone in marrow cell lineages and apoptosis cells in myelodysplastic syndrome (MDS) with deletion of chromosome 20q. Monoclonal antibodies recognizing myeloid precursors (CD15), erythroid precursors (GPA), T cells (CD3(+)CD56(-)CD16(-)), B cells (CD19), NK cells (CD3(-)CD56(+)CD16(+)) were used to sort bone marrow cells in a MDS patient with del (20q) by fluorescence activated cell sorting (FACS). Annexin V-FITC and PI were used to sort bone marrow Annexin V(+)PI(-) and Annexin V(-)PI(-) cells by FACS. The sorted positive cells were detected by interphase dual-color fluorescence in situ hybridization (D-FISH) using a LSI D20S108 probe (Spectrum Orange) and a Telvysion TM 20p probe (Spectrum Green). FACS and FISH analysis were also performed on the samples from 4 cases with normal karyotype. The results showed that the proportions of MDS clone in the myeloid and erythroid precursors were 70.50% and 93.33% respectively, in the RAEB-1 patient with del (20q) and were obviously higher than that in control group (5.39% and 6.17%). The proportions of abnormal clone in T, B and NK cells were 3.23%, 4.32% and 5.77% respectively and were less than that in control group (5.76%, 4.85%, 6.36%). The percentage of apoptotic cells in the bone marrow nucleated cells was 16.09%. The proportions of MDS clone in Annexin V(+)PI(-) and Annexin V(-)PI(-) cells were 32.48% and 70.11%, respectively. It is concluded that most myeloid and erythroid precursors are originated from the abnormal clone in MDS with del (20q). A little part of apoptotic cells are derived from the abnormal clone.