Biomedical subjects

Fan-yi Meng

Publications and source records attributed to Fan-yi Meng.

26 records · Page 2Linked to original sources

PubMed2003

[Immunophenotyping of 106 adult patients with acute leukemia by flow cytometry].

OBJECTIVE: To study the immunophenotyping of adult patients with acute leukemia and its association with the prognosis. METHODS: Immunophenotyping was performed in 106 adult patients with acute leukemia by three-color flow cytometry analysis using CD34/SSC gating. RESULTS: The antigens expressed in 71 patients with acute myeloid leukemia (AML) were mainly CD13, CD33, HLA-DR, CD34 and CD117. Lymphoid antigen expression was identified in 23.9% adult AML patients and CD56 antigen expression in 15.5% of the AML patients. In 29 patients with acute lymphoblastic leukemia (ALL), the expressed antigens were mainly HLA-DR, CD10, CD19, CD34 and CD7, and 34.5% of these patients were found to be positive for myeloid antigen expression. Complete remission (CR) rate in AML patients with lymphoid antigen expression after chemotherapy was lower than that in AML patients without lymphoid antigen expression (52.9% vs 77.8%, P<0.05), and no significant impact was noted of myeloid antigen expression in ALL on the CR of the patients (70.0% vs 94.7%, P>0.05). The CR rate in AML with CD56 antigen expression was lower than that in AML without CD56 expression (36.4% vs 78.3%, P<0.025), and the CR rate in CD34+ AML was lower than that in CD34- AML (56.0% vs 80.4%, P<0.05). CONCLUSIONS: Gating of CD45/SSC can eliminate the interference of normal cells to render more reliable immunophenotyping results. The expressions of CD56+, CD34+, lymphoid antigen in adult AML patients, who have lower CR rate, often signify poor prognosis.

Adolescent↗

PubMed2003

[Effect of autocrine vascular endothelial growth factor on the biological activity of acute myeloid leukemia cell line HL-60].

OBJECTIVE: To explore the effect of autocrine vascular endothelial growth factor (VEGF) on the abnormal proliferation of HL-60 cells. METHODS: HL-60 cells were transfected via lipofictamine with the VEGF(165) cDNA sense vector (HL-60/ VEGF(165)) and with the PcDNA3.1(-)-vector (HL-60/neo) as the control. Reverse transcription-polymerase chain reaction (RT-PCR) was used for detecting VEGF mRNA in the transfected cells. VEGF concentrations in the cell culture supernatant were determined by enzyme-linked immunosorbent assay (ELISA), and cell proliferation was determined by MTT assay and colony-forming assay in vitro. Flow cytometric Annexin-V-FITC/ PI dual-labeling technique was employed to observe the effect of VEGF(165) cDNA transfection on the apoptosis of HL-60 cells. RESULTS: The levels of VEGF mRNA expression by HL-60/VEGF(165) cells were higher than HL-60/neo, with the mean VEGF quantity in the supernatant of HL-60/VEGF(165) cell culture being 399.07+/-12.45 ng/L, which was 2-fold higher than that in the supernatant of HL-60/neo cells (184.45+/-10.53 ng/L) (P<0.01). The growth rate of HL-60/VEGF(165) cells was significantly accelerated as compared with that of the control cells, and the colony formation capacity of the former cells also increased significantly (P<0.05), with the average colony number of 157.00+/-17.00/500 cells vs 110.00+/-12.90/500 cells of HL-60/neo cells. Less apoptotic cells were identified among HL-60/VEGF(165) cells than in HL-60/neo cells in the same culture condition. CONCLUSION: Autocrine VEGF plays an important role in the proliferation and apoptosis of acute myeloid leukemia cells.

Apoptosis↗

PubMed2003

[Modified FLAG regimen in the management of refractory acute myeloid leukemia].

OBJECTIVE: To evaluate the therapeutic effect of modified FLAG regimen in the management of refractory acute myeloid leukemia (AML). METHODS: Sixteen patients with refractory AML were divided into two groups. In modified FLAG regimen group (n=10), the patients received fludarabine (Flu, 50 mg/d, VDx5 d) and Ara-c (200 mg/d, VDx5 or 7 d). The regimen for classic FLAG group (n=6) consisted of Flu (50 mg/d, VDx5d), Ara-C (500 or 1,000 mg/d, VDx5d) and G-CSF (300 microg/d, x5 d, subcutaneously injected 4-6 hours before chemotherapy). Each patient received subcutaneous G-CSF (300 microg/d) when the white blood cell count was lower than 1.0x10(9)/L till the condition was corrected. RESULTS: The total complete remission(CR) rate of the 16 patients was 50% (8/16). Seven patients in modified group achieved CR (70%) and only one of the classic group did (17%, P<0.05). Episodes of infections were lower in modified group than in the classic group (50% vs 83%). CONCLUSION: Modified FLAG regimen is more likely than classic FLAG regimen to achieve CR and reduce infections in patients with refractory AML.

Adolescent↗

PubMed2003

[Quadruple therapy with CsA, MTX, MMF and ATG for preventing graft-versus-host disease in unrelated donor hematopoietic stem cell transplantation].

OBJECTIVE: To evaluate the efficacy of quadruple therapy with cyclosporine (CsA), methotrexate (MTX), mycophenolate mofetil (MMF) and low-dose antithymocyte globulin (ATG) for graft-versus-host disease (GVHD) prophylaxis in unrelated donor hematopoietic stem cell transplantation (URD-HSCT). METHODS: Thirteen patients with leukemia received URD-HSCT, of whom 11 had HLA genotypes and 2 had mismatch for 1 genetic locus. Another 11 leukemia patients all serologically matched underwent related donor (RD)-HSCT. Total body irradiation (TBI) plus cyclophosphamide (CTX) was adopted in 19 cases and modified BuCY conditioning regimen (hydroxyurea, busulfan, Ara-C, Cyclophosphamide ) in the other 5 cases. All the patients received CsA+MTX protocal for GVHD prophylaxis, and in those undergoing URD-HSCT, additional MMF and low-dose ATG were used. RESULTS: The incidence and severity of regimen-related toxicity differed little between unrelated and related transplantation. Acute GVHD (aGVHD) occurred in 46.2% of the patients undergoing URD- HSCT and in 55.6% of those with RD-HSCT, respectively. Four patients had chronic GVHD (cGVHD), in the 7 ones who could be followed up after URD-HSCT; 6 of the 9 patients with RD-HSCT developed cGVHD postoperatively. One patient with URD-HSCT died of hemorrhagic cystitis and another with RD-HSCT died of cytomegalovirus (CMV) pneumonia. The at one-year disease-free survival rate was 87.5% and 90.9% in patients with unrelated and related transplantation respectively. Significant difference was not noted in the positivity rate of CMV antigen between the patients receiving URD-HSCT or RD-HSCT. CONCLUSION: CsA+MTX in combination with MMF and low-dose ATG may decrease the incidence and severity of aGVHD without increasing transplant-related mortality or CMV infection.

Adolescent↗

PubMed2003

[STI 571 for treating 19 patients with chronic-phase chronic myeloid leukemia].

OBJECTIVE: To compare the therapeutic effects of STI 571 in treating Philadelphia chromosome (Ph)-positive patients with chronic-phase and acceleration phase chronic myeloid leukemia (CML-CP and CML-AP, respectively). METHODS: A total of 19 CML patients with Ph chromosome and/or fluorescence in situ hybridization (FISH)-bcr/abl fusion gene positivity rates over 90% and a median age of 38 years were recruited in this study, 12 of whom had previously failed to respond to interferon-alpha. Five of the 19 patients were in accelerated phase and 14 in chronic phase, 9 of the latter patient group in early stage of CML-CP (within 1 year since diagnosis) and 5 in advanced stage (3-6 years since diagnosis). All the patients were given oral STI 571 at the dose of 300-500 mg/d for a median treatment course of 5 months, and the 5 patients with CML-AP also received homoharringtonine at dose of 1-2 mg/d for an average of 1.5 treatment cycles (7-14 d for a complete treatment cycle). The Ph chromosome and the FISH-bcr/abl were analysed again 3 months after the treatment. RESULTS: STI 571 induced 100% complete hematological remission (CHR) and 79% major cytogenetic responses (MCR) in these patients. The complete cytogenetic remission (CCR) rates of CML-AP patients and CML-CP patients in advanced stage were lower than that of CML- CP patients in early stage (0% and 40% vs 88.9%). CONCLUSION: STI 571 can achieve high rate of CHR and MCR in CML-CP patients, especially in those in early stage of the disease.

Adolescent↗

PubMed2003

[Analysis of T cell receptor V gamma I-J gamma gene rearrangement in elderly patients with acute leukemia].

OBJECTIVE: To obtain insight into the molecular mechanism of acute leukemia in elderly patients in relation to the clinical features of the disease. METHODS: DNA specimens were obtained from 34 elderly patients with acute nonlymphoblastic leukemia (ANLL), 9 elderly patients with acute lymphoblastic leukemia (ALL) and 10 healthy blood donors. Polymerase chain reaction (PCR) coupled with single-strand conformation polymorphism (SSCP) was performed to detect T cell receptor (TCR) V gamma I-J gamma gene rearrangement. RESULTS: In the 34 elderly ANLL patients, 47.1% (16/34) were found with TCRV gamma I-J gamma gene rearrangement, showing a higher rate of the rearrangement than in younger ANLL patients (P<0.025). TCRV gamma I-J gamma gene rearrangement was identified in 7 (77.8%) of the 9 elderly patients with ALL, and 3 of the identified cases had oligoclonal/ subclonal rearrangement, suggesting a higher rate of oligoclonal/subclonal rearrangement in elderly ALL patients than in younger ALL patients (P<0.01). None of the blood donors was found with TCRV gamma I-J gamma gene rearrangement. The complete remission rate was lower in the elderly ANLL patient with TCRV gamma I-J gamma gene rearrangement than in those without (P<0.05). CONCLUSION: The detection of TCRV gamma I-J gamma gene rearrangement can be of value in assessing the therapeutic effect and making prognostic prediction in elderly patients with acute leukemia.

Aged↗

PubMed2003

[Surface morphology of CD34+ cells under atomic force microscope].

OBJECTIVE: To observe the difference in surface morphology and structure between CD34(+) cells from normal human subjects and from patients with leukemia. METHODS: Bone marrow mononuclear cells from 3 normal human subjects and 3 patients with M2b leukemia were collected by Percoll gradient centrifugation, followed by purification of CD34(+) cells by means of immunomagnetic bead separation (MiniMAC) and examination with flow cytometry. The morphology of the cells were then observed with optical and atomic force microscope (AFM) in air. RESULTS: No significant difference was identified between the two cells under optical microscope. With atomic force microscope, numerous microvilli were observed on the surface of CD34(+) cells, and the normal cells and those from the leukemic patients showed significant difference in terms of the roughness of the cell surface. CONCLUSION: Normal CD34(+) cells have more rough and erosive surface structure than leukemic CD34+ cells (M2b).

Antigens, CD34↗

PubMed2003

[Autogeneic peripheral blood hemopoietic stem cell transplantation for chronic myeloid leukemia with imatinib mesylate-induced negative Philadelphia chromosome].

OBJECTIVE: To study the possibility of curing chronic myeloid leukemia with autogeneic hemopoietic stem cell transplantation in patients with negative Philadelphia (Ph) chromosome induced by imatinib mesylate (STI 571) treatment. METHODS: Two patients with chronic myeloid leukemia in chronic phase, who had 90% Ph chromosome-positive cells and bcr/abl fusion gene-positive cells as shown by interphase fluorescence in situ hybridization (I-FISH), failed to respond favorably to interferon-alpha therapy in the treatment courses of 7 and 8 months, respectively. Treatment with STI 571 at a daily dose of 300 to 400 mg for 5 months to 8 months was subsequently implemented, after which the Ph chromosome and bcr/abl fusion genes became normal in detection for 3 times. Peripheral blood haemopoietic stem cell mobilization was then initiated by intravenous injection of cytarabine (2.0 g/d) for 3 days, etoposide (0.2 g/d) for 3 d and cyclophosphamide (1.0 g/d) for one day. When the white blood cell was below 1.0x10(9)/L, the G-CSF (300 microg/d) was administered subcutaneously for 5 or 6 d, and the peripheral blood mononuclear cells were collected by CS3000 Plus blood cell separator. The percentage of bcr/abl fusion gene-positive cells among CD34(9) cells enriched by MiniMAC ranged from 11% to 14%. After 3 or 4 weeks, the patients received total body irradiation at 9 Gy given in 2 fractions, with intravenous injection of cyclophosphamide (60 mg/kg daily) and etoposide (300 mg/d) for 2 d. On the day of transplantation, the collected mononuclear cells were 4.17x10(8)/kg and 3.9x10(8)/kg, with CD34(+)/ cells reaching 4.89x10(6)/kg.b.w and 4.89x10(6)/kg. CsA was also used since day -1 to day +13 of the transplantation for prevention of graft-versus-host disease. G-CSF was administrated daily at the dose of 300 microg subcutaneously from day +3 to +12. RESULTS: After the transplantation, the absolute neutrophil count (ANC) took a mean of 11 d to exceed 0.5x10(9)/L in these two patients, and 19 and 21 d, respectively, were needed for the platelet count to exceed 20x10(9)/L. The two patients showed cytogenetic relapse at 120 and 300 d after the transplantation, respectively. CONCLUSION: Autogeneic peripheral blood stem cells transplantation after Ph chromosome is negative in patients with chronic myeloid leukemia, who receive STI 571 treatment, may also relapse, and more radical elimination of Ph chromosome-positive cells is needed.

Adult↗