Biomedical subjects

Fang-Yuan Chen

Publications and source records attributed to Fang-Yuan Chen.

5 recordsLinked to original sources

PubMed2005

[Effect of recombinant human granulocyte colony-stimulating factor on neutrophil morphology, function and phenotype in patients with acute leukemia undergoing chemotherapy].

This study was to explore the effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on neutrophil morphology, function and phenotype in patients with acute leukemia undergoing chemotherapy. Neutrophil morphology was observed under microscope with oil immersion; phagocytotic function was examined by measuring the amount of hydrogen peroxide produced by neutrophil; chemotaxis was analyzed by agarose method; oxidative burst was analyzed by flow cytometry using immunofluorescence technique; neutrophil phenotype was analyzed by flow cytometry and immunofluorescence techniques. The results showed that after rhG-CSF administration, the increased "toxic" granulation, vacuoles and Döhle bodies were observed in neutrophils of patients with acute leukemia. Compared with normal control, the functions of phagocytosis, chemotaxis, oxidative burst of neutrophil were impaired after chemotherapy, while these functions were enhanced and returned to normal level or even to be exceeded after administration of rhG-CSF. In patients with acute leukemia the neutrophil presented significantly higher expression of CD64 and CD62L than that in normal control, and a mild increase of CD64 expression and significant increase of CD62L expression were found in patients after rhG-CSF treatment. No modifications of CD16, CD32, CD14 and CD11b expression were detected in these patients before or after G-CSF administration. It is concluded that rhG-CSF administration can modify the morphology, function and phenotype of neutrophils in the patients with acute leukemia undergoing chemotherapy, and these modifications of neutrophil behavior may be supposed to be a reason for the enhancement of organism anti-infection ability.

Acute Disease↗

PubMed2004

[Effect of ATRA and DNR on the expression and secretion of VEGF in leukemic cells].

OBJECTIVE: To investigate the expression of VEGF mRNA and secretion of VEGF protein in NB4 and HL-60 cells affected by all-trans retinoic acid (ATRA) and daunorubincin (DNR) respectively. METHODS: Semi-quantitative RT-PCR and ELISA were used to study the expression of VEGF mRNA and secretion of VEGF protein in NB4 and HL-60 cell lines treated by ATRA and DNR respectively. RESULTS: VEGF was expressed in both NB4 and HL-60 cells. The expression of VEGF mRNA and secretion of VEGF protein could be down-regulated by ATRA and DNR respectively in a time and dose dependent manner. CONCLUSION: Besides inducing apoptosis and restraining proliferation of leukemic cells, ATRA and DNR exerted their anti-leukemia effects by reducing angiogenesis via reduction of angiogenic reaction stimulating signals.

Apoptosis↗

PubMed2004

[Restorative effect of quercetin on subcellular distribution of daunorubicin in multidrug resistant leukemia cell lines K562/ADM and HL-60/ADM].

BACKGROUND & OBJECTIVE: Quercetin, a widely distributed natural flavonoid with a variety of biological functions, can reverse multidrug resistance (MDR) in leukemia according to recent researches. This study was to investigate the mechanism of quercetin restoring subcellular distribution of daunorubicin (DNR) in multidrug resistant leukemia cell lines, K562/ADM and HL-60/ADM, and reversing their MDR. METHODS: MTT cell viability assay was used to verify the sensitization of DNR by quercetin in K562/ADM and HL-60/ADM cells,and determine the reverse concentration extent,confocal laser scanning microscope was used to observe the subcellular distribution of DNR in K562/ADM and HL-60/ADM cells,and relevant sensitive cell lines, K562/S and HL-60/S,before and after quercetin exposion. RESULTS: Compared with K562/S and HL-60/S cells,20-40 micromol/L of quercetin in vitro remarkably enhanced the sensitivity of K562/ADM and HL-60/ADM cells to DNR, restore the subcellular distribution of DNR, so as to reverse MDR. CONCLUSION: quercetin could be a candidate of effective multidrug resistance-reversing agent in leukemia chemotherapy.

Antibiotics, Antineoplastic↗

PubMed2004

[Dynamic observation of vascular endothelial growth factor (VEGF)/VEGF-receptors expression in acute leukemia].

OBJECTIVE: To investigate the expression of vascular endothelial growth factor (VEGF)/VEGF-receptors and its relation to bone marrow angiogenesis in acute leukemia patients before and after chemotherapy. METHODS: Bone marrow biopsies from 122 cases with different stages of human acute leukemia were immunostained with anti-vascular endothelial growth factor, anti-fms-like tyrosine kinase (Flt-1) and anti- kinase-domain insert containing receptor (KDR) antibodies with envision two-step immunohistochemical staining method. RESULTS: The expression of VEGF and KDR protein in remission patients was 5.3 (3.3 - 9.0) and 2.0 (1.0 - 4.0) being significantly lower than newly diagnosed untreated patients 6.0 (3.3 - 12.0) and 5.3 (3.3 - 8.0) (P < 0.05, 0.01). However nonsignificant decrease was shown among non-remission patients. In relapsed patients the expression of VEGF and KDR was significantly increased as compared with that in newly diagnosed patients. Flt-1 staining levels were in the same range between the newly diagnosed untreated patients and control group (P > 0.05), but significantly increased in remission or relapse patients, being 3.3 (1.7 - 5.3) in the remission group and 3.3 (2.0 - 5.3) in the relapse group (P < 0.01). Expression of VEGF and KDR protein was significantly higher in patients with a high degree of bone marrow microvessel counts as compared with those with a low degree and the expression correlated well with microvessel counts (P < 0.01). There was a positive correlation of the percentage of bone marrow blasts with VEGF and KDR expression in AML patients (r = 0.429, 0.359; P = 0.005, 0.02), and with VEGF expression in ALL patients (r = 0.522; P = 0.03). CONCLUSION: VEGF and its two specific cellular receptors are expressed in both haematopoietic cells and endothelial cells. VEGF may be a autocrine factor and modulates the angiogenic reaction in bone marrow as a paracrine factor. VEGF and its cellular receptor KDR may constitute promising targets for antiangiogenic and antileukemic treatment strategies.

Adolescent↗

PubMed2001

[Effects of Red Orpiment on Cell Morphology and Expression of PML mRNA and Protein in NB4, and HL-60 Cells]

In this study the effects of red orpiment on NB4 and HL-60 cells were tried to determine. Semi-quantitative RT-PCR to determine the PML mRNA expression, immuno-fluorcscence study, together with the fluorescence stain and morphological observations were used. The results showed that: (1) red orpiment induces apoptosis morphologically in NB4 and HL-60 cells, the morphology of typical apoptosis can be seen in NB4 and HL-60 cells after 12 hours of treatment with red orpiment. Through the Wright's stain, we can see the extensive membrane blebbing, condensation of heterochromatin, and cell fragmentation, apoptotic body appearing. Many dead cells can be found on the second day. (2) in NB4 cells, red orpiment is shown to induce the PML-RARalpha chimera disappearance and to reorganize then to degradation of PML nuclear bodies which also seen in HL-60 cells, indirect immunofluorescence staining of PML with a specific monoclonal antibody was performed in control and treated cells. In NB4 cells, the control was diffusely microspeckled pattern of immunoreactivity. Upon red orpiment treatment, the microspeckled pattern disappeared, PML protein reversed into normal location. and the the size and the brightness of the particles were increased obviously. The normal nuclear distribution of PML protein was seen in untreated HL-60 cells. After treatment with red orpiment, in the nuclei of HL-60 cells, the size and the brightness of the particles were also increased. After two days of treatment with red orpiment, the immunofluorescent particles in cells almost disappeared. (3) the expression of PML mRNA is not changed in red orpiment-treated cells, RT-PCR to determine the PML mRNA expression in NB4 and HL-60 cells treated with red orpiment, the expression results are similar to the controls, that to say, the PML mRNA lever is unaffected. It was concluded that, red orpiment induced PML to play the effects of induce apoptosis in leukemia cells at the translational level and inhibited the proliferation of leukemia cells.

Journal Article↗