Relapse, which puzzled several generations of hematologists, is the bottle-neck of radical treatment for leukemias. The progress of Human Microbiome Project at the beginning of 21st century suggested that human body was a super-organism constituted by the core of human cells and symbiotic microorganisms. The elucidation and characterization of endogenous retrovirus and prion protein suggested the possible effects of co-evolutional microorganisms on human health. Recently, the elucidation of the roles of tunneling nanotubes in intercellular communication and transportation suggested a novel way for cellular communication and transport of oncogenic materials. The role and significance of in vivo cell fusion have been studied in more detail. On the other hand, donor cell leukemia was reported. All of these approaches provide novel insights for studying the mechanism of leukemia relapse. Based on previous work, the authors suggest the hypothesis: there are two possible mechanisms for the relapse of leukemias: the minimal residual disease (MRD) and intercellular transportation of oncogenic materials.
Cell Fusion ; Humans ; Leukemia ; pathology ; Neoplasm, Residual ; pathology ; Recurrence

OBJECTIVETo study melanoma cell fusion and find a highly efficient fusion method for tumor cells.

METHODSMelanoma cells were labeled with green fluorescent protein and red fluorescent protein, respectively, and fused by a modified phytohaemagglutinin (PHA)-ECM830 fusion method. Melanoma fusion cells were selected by the fluorescence activated cell sorting. DNA content was determined by propidium iodide staining.

RESULTSMelanoma cells were labeled with green fluorescent protein and red fluorescent protein markers and successfully fused through PHA-ECM830 fusion method. The fusion efficiency (7.18%) was much higher compared with ECM830 electricfusion method (0.50%). Melanoma fusion cells were successfully obtained by the fluorescence activated cell sorting.DNA content was doubled in melanoma fusion cells compared to B16-F10 melanoma cells. The proliferation rate of melanoma fusion cells was significantly decreased in vitro and in vivo.

CONCLUSIONSWe successfully obtained the melanoma fusion cells by the improved PHA-ECM830 fusion method. The proliferation rate of melanoma fusion cells dramatically decreases.

Animals ; Cell Fusion ; methods ; Cell Line, Tumor ; Cell Proliferation ; Melanoma, Experimental ; pathology ; Mice ; Phytohemagglutinins ; pharmacology

Bioseperation, cell cultivation and cell electrofusion are three main biological processes in space laboratories. Microgravity is free from the influences of convection and sedimentation. Therefore, it is an ideal realm for cell electrofusion and hence it can be used in the research of monoclonal antibody, cross breeding and microgravity biology. This paper reviews the research of cell electrofusion under microgravity, including the changes of cytoskeleton and the mechanism of cell electrofusion.
Animals ; Cell Culture Techniques ; Cell Fusion ; methods ; Electric Stimulation ; Electroporation ; methods ; Mice ; Microelectrodes ; Weightlessness ; Weightlessness Simulation

OBJECTIVETo acquire homozygous tetraploid germplasm of Rhodiola sachalinensis.

METHODPEG-mediated protoplast fusions were conducted using callus of Rh. sachalinensis as materials. Protoplast fusion products were embedded and cultured in low-density, low-melting-point agar and marked according to the protoplast size, and single-celled sister lines were established to acquire genetically homozygous tetraploid germplasm.

RESULTR(D) and R(M) of newborn daughter cells or protoplasm, metaphase cells or protoplasm were approximately in line with the formula R(D) = 0.793 7R(M). The change range in diameter of the diploid cells without fusion, two protoplasts fusion product were: 16.7 microm < or = R < 21.3 microm, 21.0 microm < or = R' < 26.8 microm respectively. There is an overlap between the two diameter ranges. The protoplast inoculation density of 1 x 10(4) cells x mL(-1) was appropriate when protoplasts were anchored by low-intensity, low-melting-point agar. Under the conditions of this density, plating efficiency was high and single cell origin of the sister lines microclones grew rapidly, and it was easy to mark the single cell microclones, and separate from each other to subculture. The chromosome counts results showed that chromosome numbers of diploid and tetraploid of single cell lines were 26 and 52, respectively. The result from flow cytometry assay showed that there is no presence of chimerism in single-cell regeneration plantlets.

CONCLUSIONThe results of this study provide a scientific basis for polyploid breeding of Rh. sachalinensis.

Cell Fusion ; methods ; Polyethylene Glycols ; pharmacology ; Polyploidy ; Protoplasts ; cytology ; drug effects ; Rhodiola ; cytology ; drug effects ; genetics

Child ; Fusion Proteins, bcr-abl ; genetics ; Humans ; Mutation ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics

Aged ; Female ; Fusion Proteins, bcr-abl ; genetics ; Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; RNA Precursors

In order to expand gene resources and improve Brassica napus cultivars, protoplasts isolated from hypocotyls of Brassica napus cv. Huayou No. 3 and Eruca sativa were fused by PEG-high Ca2+-high pH. Fusion frequency was up to 18.2% when fusion system contained 5 x 10(5) protoplasts/mL, and when PEG concentration of fusion agents were 35% and when fusion time was 25 min. Then the fused protoplasts were cultured by the method of thin liquid layer at the density of 1 x 10(5) protoplasts/mL in improved KM8p medium supplemented with 1.0 mg/L 2,4-D, 0.5 mg/L NAA, 0.5 mg/L 6-BA, 200 mg/L inositol, 300 mg/L protein hydrolysate, and the combinations of 0.1 mol/L sucrose and 0.2 mol/L glucose and 0.2 mol/L mannitol for osmotic regulator, the frequency of callus regeneration was up to 6.8%. When the micro-calli transferred to the proliferation medium that contained B5 salts, 0.087 mol/L sucrose, 0.2 mg/L 2,4-D, 0.5 mg/L NAA, 0.2 mg/L 6-BA and 0.5% Agar, pH 5.8, have grown up to 3-5 mm of diameter, the calli were transferred to the differentiation medium that contained MS salts, 0.087 mol/L sucrose, 0.1 mg/L IAA, 0.8 mg/L 6-BA, 0.8% Agar, pH5.8, the shoots were regenerated in 4 weeks and its frequency was up to 32.8%. Then 2-3 cm shoots were transferred to 1/2 MS medium with 0.5 mg/L IBA+0.2mg/L 6-BA, plantlets were obtained in 14 days and the plantlet frequency was up to 88%. When the protoplasts of Eruca sativa were treated with UV radiation for 2 minutes calli and plantlets have been regenerated, treated for 4 min only calli have been regenerated, and treated for more than 5 min calli have not been regenerated. The callus regeneration and callus proliferation and plant regeneration from symmetric fusion were more than from asymmetric fusion. 16 hybrid plantlets have been regenerated on 21 piece of hybrid calli identified by cytology method.
Brassica ; genetics ; Brassicaceae ; genetics ; Cell Fusion ; Hybrid Cells ; Hybridization, Genetic ; Protoplasts ; Regeneration ; Ultraviolet Rays

BACKGROUND: Immunotherapy using dendritic cells (DC) loaded with tumor antigens may represent a potentially effective method for inducing antitumor immunity. We evaluated the effectiveness of DC-based antitumor immune response in various conditions. METHODS: DC were cultured from peripheral blood mononuclear cells (PBMNC) in myelogenous leukemia (ML) and lysates of autologous leukemic cells are used as tumor antigen. The effectiveness of interleukin-12 (IL-12) and CD40L (CD154) on the antigen presenting function of lysates-loaded DC was analyzed by proliferation, cytokine production, and cytotoxicity tests with activated PBMNC (mainly lymphocytes). For generating antigen-loaded DC, direct fusion of DC with ML was studied. RESULTS: Antigen loaded DC induced significantly effective antitumor immune response against autologous leukemic cells. Administration of IL-12 on the DC based antitumor immune response showed higher proliferation activity, IFN-gamma production, and cytotoxic activity of PBMNC. Also, fused cell has a potent antitumor immune response. CONCLUSION: We conclude that lysates-loaded DC with IL-12 may be effectively utilized as inducer of antitumor immune reaction in ML and in vivo application with DC-based antitumor immunotherapy or tumor vaccination seems to be feasible.
Antigens, Neoplasm ; CD40 Ligand ; Cell Fusion ; Dendritic Cells* ; Humans ; Immunotherapy ; Interleukin-12* ; Leukemia ; Leukemia, Myeloid* ; Vaccination

We represent a pathologically proven case of a four-year-old male patient with renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion, which is rare but more frequent in children or young adults. Computed tomography showed about 2.5 cm size ill-defined mass in the right kidney. The mass was hyperechoic on ultrasound. Magnetic resonance imaging demonstrated a mass with capsular enhancement and diffusion restriction. We present a case of Xp11.2 renal cell carcinoma and provide review of the literature.
Carcinoma, Renal Cell ; Child ; Diffusion ; Gene Fusion ; Humans ; Kidney ; Magnetic Resonance Imaging ; Male ; Young Adult

OBJECTIVETo investigate the inhibitory effect of RNA interference on chronic myeloid leukemia (CML) bcr/abl oncogene expression.

METHODSThe small interference RNAs (siRNAs) were synthesized in vitro. K562 cells stably expressing bcr/abl gene were transfected with the siRNA by electroporation, both the non-transfected cells and non-specific siRNAs transfected cells were taken as controls. The enhanced green fluorescent protein (EGFP) plasmid was used as positive control and the transfection efficiency was detected by flow cytometry. Inhibitory effect of siRNAs was demonstrated by real-time quantitative RT-PCR and Western blots. Cell proliferation was measured by MTT assay and apoptosis by Annexin V-FITC assay.

RESULTSThe transfection efficiency was about 70%. The synthesized siRNAs inhibited CML bcr/abl oncogene expression at both mRNA and protein levels. siRNAs could inhibit K562 cell proliferation to 47% and 56% at 24 h and 48 h after transfection, respectively, and induce cell apoptosis from 1.00% in control group to 15.05% and 19.4% at 24 h and 48 h respectively.

CONCLUSIONAt the cell level, inhibition of CML bcr/abl oncogene expression by chemically synthesized siRNAs provides the new method for anti-leukemia study.

Apoptosis ; genetics ; Cell Proliferation ; Fusion Proteins, bcr-abl ; genetics ; Humans ; K562 Cells ; RNA, Small Interfering ; Transfection