ABSTRACT
@#Objective To examine the sensitivity of human glioblastoma multiforme cell line BT325 to 5 antineoplastic drugs, including cisplatin (DDP), teniposide (VM26), nimustine (ACNU), temozolomide (TMZ) and vincristine (VCR). Methods BT325 cells were incubated in DMEM with 10% or 20% fetal bovine serum (FBS) or without FBS respectively. The cell numbers were counted at 24 h, 48 h, 72 h,96 h, 120 h, and 144 h, then platting and growth curve were drafted. Cell counting kite-8 was used to detect the influence of 5 drugs with different concentrations on human glioma cell line BT325. Results DDP and VM26 significantly suppressed BT325 cells(>75%) viability in a dose-dependent manner, while VCR inhibited BT325 cells (50%) growth without dose-effect relationship. In contrast, ACNU and TMZwere not effective on the viability of BT325 cells. Conclusion BT325 cells were very sensitive to chemotherapeutic drugs DDP amd VM26.
ABSTRACT
Objective To evaluate the radiobiological effect of different irradiation fractionated regimens in human glioma cells ( BT 325 cell line). Methods The xenografts in Balb/c-nude mice were irradiated with different single and fractionated regimens. The single fraction dose was 10, 20, 30, 40 and 60 Gy, respectively. The fractionated regimens were 2 Gy × 5 fractions ( irradiated every day), and 3 Gy ×3 fractions (irradiated every other day), 3 Gy × 5 fractions (irradiated every day) and 4 Gy × 3 fractions (irradiated every other day), with total doses of 125 Gy, 114 Gy, 126 Gy and 112 Gy, respectively. The growth curve was used to evaluate the tumor doubling time. clonogenic assays was performed to draw the cell survival curve and analyze the radiobiological parameters with doses of 1, 2, 4, 6, 8 and 10 Gy. T1/2 was measured by comet assay. Results Tumor regression were not observed by single fraction irradiation, 2 Gy × 5 fractons and 3 Gy × 3 fractions irradiation regimens. The tumor regress was more significant with the increas of fraction dose. The 4 Gy × 3 fractionrs inhibited tumor more though not curing tumor. The cell doubling time of the BT 325 cell was 30. 16 h and the tumor doubling time of the xenograft was 43 days.When fitted with L-Q model ,α was 0. 36 Gy -1 and β was 0. 057 Gy -2. When fitted with the single-hit multitarget model, D0 was 1. 394 Gy, Dq was 2. 127 Gy and SF2 was 0. 714, respectively. The T1/2 was 9. 999min. Conclusions Glioma is a radioresistant tumor. Increase of the fraction dose improves recent effect.Further study is needed to control the tumor stem cells.
ABSTRACT
@#ObjectiveTo observe the growth of BT-325 human glioma cells after interfering volume-regulated chloride channel ClC-2 gene.MethodsTwo expression recombinant vectors of ClC-2 gene were designed and constructed. The primary plasmid, pSUPER.puro-shRNA, and the two recombinant plasmids, pSUPER.puro-shRNA-ClC-21 and pSUPER.puro-shRNA-ClC-22, were transfected into BT-325 cells by LipofectamineTM2000 (Groups: control, PP1 and PP2, respectively). The mRNA expression of ClC-2 gene was detected with reverse transcription polymerasse chain reaction (RT-PCR), the cellular survival was determined with MTT assay, and the cell cycle was measured with flow cytometry (FCM). ResultsClC-2 mRNA expression and the growth of the cells in PP1 and PP2 groups were significantly lower than that of control group. The cell cycle progression was blocked in G1 phase (PP1 and PP2 vs control,P<0.01). ConclusionThe growth of BT-325 human glioma cells is prevented by knockdown of ClC-2 gene expression, which may be one of the novel targets to inhibit growth of human malignant glioma cells.
ABSTRACT
Objective: To investigate a new method for improving the therapeutic effect on malignant glioma. Methods: A new type of killer cells, named GS-LAK, was induced by means of costimulating the peripheral ginsenoside(GS) and interleukin-2 (IL-2). Comparing with control group-LAK cells, cytotoxicity of GS-LAK cells against malignant glioma cells(BT325) was examined with MTI method. Results: It showed that GS-LAK cells exhibited some advantages over LAKcells in proliferation, cytotoxicity, as well as the utilizing of IL-2. Conclusion: The application of GS-LAK cells mightopen a new prospect to clinical therapeutic approach to malignant glioma.
ABSTRACT
The cytoskeleton of BT_(325), a human glioma cell line, was studied by immunofluorescence microscopy. The effects of different fixatives and buffers on microtubules, microfilaments and intermediate filaments were also compared. It was observed that besides microtubules and microfilaments all cells expressed vimentin. However, only a small fraction of the cells were GFAP positive. We conclude that vimentin is the main component of the intermediate filaments in BT_(325) cells. It was also observed that methanol fixation and formaldehyde fixation followed by acetone or Triton X-100 treatment gave rise to satisfactory results for microtubule immune-staining, and methanol or acidic alcohol fixation resulted in bright staining of intermediate filaments. Formaldehyde fixation also resulted in excellent staining for mierotubnles, but weaker staining for intermediate filaments.If the cells were immune-stained after treatment with Triton X-100, the composition of the buffers had profound effects on microtubules and intermediate filaments, but less effects on microfilaments.It was also observed that if Triton-treated ceils were fixed with formaldehyde before immunostaining with monoclonal antibodies to vimentin, the staining was very weak. However, if the ceils were immunostained first and then fixed with for-maldehyde the staing was quite bright. We conclude that for-maldehyd e fixation may "mask" or destroy certain epitopes on vimentin molecules.
ABSTRACT
Cells of BT_(325), a human glioblastoma cell line, were treated with 0.5% Triton X-100 and immunostained with a monoclonal antibody to vimentin and antiserum to glial fibrillary acidic protein (GFAP), and followed by fluorescence labeled secondary antibody. After observation with fluorescence microscope the cells were dehydrated in increasing grades of ethanol and then critical point-dried. The carbon-platinum coating replicas of cytoskeleton were observed by transmission electron microscopy. The morphology of whole cytoskeleton as well as the arrangement of microtubules, microfilaments and intermediate filaments were clearly observed by this technique. It was observed that the diameter of intermediate filaments highly increased in the cells stained with the monoclonal antibody to vimentin. In the samples stained with anti-GFAP intermediate filaments were decorated in some cells but undecorated in other cells. The results indicates that all BT_(325) cells express vimentin, but only a fraction of the cells express GFAP. It was also observed that if the cells were fixed with formaldehyde before immunostaing with the monoclonal antibody to vimentin, the diameter of the intermediate filaments only slightly increased. However, the diameter of the intermediate filaments highly increaed in the cells stained firstly with the monoclonal antibody to vimentin and followed by formaldehyde fixation. This result is in accord with that of our previous immunofluorescence study. It indicates that formaldehyde fixation may "mask" certain epitopes on vimentin molecules.