To explore the effect of NF κB on bcl x gene transcription in extended drug resistance leukemia cell line HL 60/E6, drug resistant subline HL 60/E6 was derived by intermittently exposing HL 60 cells to 6 ng/ml ...To explore the effect of NF κB on bcl x gene transcription in extended drug resistance leukemia cell line HL 60/E6, drug resistant subline HL 60/E6 was derived by intermittently exposing HL 60 cells to 6 ng/ml epirubicin. Indirect immunofluorescence was used to demonstrate the location of NF κB RelA in HL 60/E6 cells. FCM analysis and RT PCR were used to detect the efficiency of liposome mediated ODN transfection and the change of bcl x L mRNA levels after 5 μmol/L phosphorothioate (PS) derivatized antisense (AS) oligodeoxynucleotide (ODN) directed to RelA was transferred into HL 60/E6 cells. The results showed that RelA remained persistently active and located at the nuclei of HL 60/E6 cells,but in the cytoplasm of HL 60 cells, the efficiency of liposome mediated ODN transfection was significantly higher than that of null ODN ( P <0.01 in 4 h, 6 h, 12 h, 24 h). Exposure of HL 60/E6 cells to 5 μmol/L AS PS ODN directed to RelA led to a maximal 40 % decline of bcl x L mRNA levels within 8 h. The inhibition rate of bcl x L mRNA was (15±1.79) %, (28±2.34) %, (40±3.47) %, (20±1.54) % in 4 h, 6 h, 8 h, 15 h, respectively, but it was less than 15 % in control group. It was concluded that NF κB was involved in regulating bcl x transcription. It was suggested that NF κB was an important factor for drug resistance in leukemia cells.展开更多
Aim To study the effect of 8 chloroadenosine (8 CA)on undifferentiatied HL 60 cell line. Methods The IC 50 of cancer cell proliferation was determined using a microculture plate reader at 570 nm (MTT) and 54...Aim To study the effect of 8 chloroadenosine (8 CA)on undifferentiatied HL 60 cell line. Methods The IC 50 of cancer cell proliferation was determined using a microculture plate reader at 570 nm (MTT) and 540 nm (SRB). Morphology of HL 60 cells was observed under a scanning electron microscope and a transmission electron microscope. The differentiation of HL 60 cells was examined by nitro blue tetrazolium reduction (NBT) and acid phosphatase assay. The cycle of HL 60 cells was analyzed by flow cytometry. Results 8 CA inhibited proliferation of eight human cancer cell lines. The IC 50 ranked in the following order: KB (0 05 μmol·L -1 ) < HL 60 (0 25 μmol·L -1 ) < Bel 7402 (0 56 μmol·L -1 ) < MCF 7 (0 65 μmol·L -1 ) < HCT (0 79 μmol·L -1 ) < HeLa (0 89 μmol·L -1 ) < BGC 823 (1 149 μmol·L -1 ) < PG (2 50 μmol·L -1 ). The scanning and transmission electron microscopy showed that the microvilli of HL 60 cell surface shortened, and the shape of HL 60 cells nuclei changed to kidney shaped, horse shoe shaped and bilob ated after treatment with 8 CA. Meanwhile, 8 CA promoted NBT reduction and increased activity of acid phosphatase in HL 60 cells in a time and concentration dependent manner. Flow cytometry analysis indicated that 8 CA induced an appreciable increase of the cell population in G 1 phase with a marked reduction in S phase. Conclusion 8 CA can induce differentiation of HL 60 cells and block the cells at G 1 phase, thus inhibiting proliferation of HL 60 cells.展开更多
文摘To explore the effect of NF κB on bcl x gene transcription in extended drug resistance leukemia cell line HL 60/E6, drug resistant subline HL 60/E6 was derived by intermittently exposing HL 60 cells to 6 ng/ml epirubicin. Indirect immunofluorescence was used to demonstrate the location of NF κB RelA in HL 60/E6 cells. FCM analysis and RT PCR were used to detect the efficiency of liposome mediated ODN transfection and the change of bcl x L mRNA levels after 5 μmol/L phosphorothioate (PS) derivatized antisense (AS) oligodeoxynucleotide (ODN) directed to RelA was transferred into HL 60/E6 cells. The results showed that RelA remained persistently active and located at the nuclei of HL 60/E6 cells,but in the cytoplasm of HL 60 cells, the efficiency of liposome mediated ODN transfection was significantly higher than that of null ODN ( P <0.01 in 4 h, 6 h, 12 h, 24 h). Exposure of HL 60/E6 cells to 5 μmol/L AS PS ODN directed to RelA led to a maximal 40 % decline of bcl x L mRNA levels within 8 h. The inhibition rate of bcl x L mRNA was (15±1.79) %, (28±2.34) %, (40±3.47) %, (20±1.54) % in 4 h, 6 h, 8 h, 15 h, respectively, but it was less than 15 % in control group. It was concluded that NF κB was involved in regulating bcl x transcription. It was suggested that NF κB was an important factor for drug resistance in leukemia cells.
文摘Aim To study the effect of 8 chloroadenosine (8 CA)on undifferentiatied HL 60 cell line. Methods The IC 50 of cancer cell proliferation was determined using a microculture plate reader at 570 nm (MTT) and 540 nm (SRB). Morphology of HL 60 cells was observed under a scanning electron microscope and a transmission electron microscope. The differentiation of HL 60 cells was examined by nitro blue tetrazolium reduction (NBT) and acid phosphatase assay. The cycle of HL 60 cells was analyzed by flow cytometry. Results 8 CA inhibited proliferation of eight human cancer cell lines. The IC 50 ranked in the following order: KB (0 05 μmol·L -1 ) < HL 60 (0 25 μmol·L -1 ) < Bel 7402 (0 56 μmol·L -1 ) < MCF 7 (0 65 μmol·L -1 ) < HCT (0 79 μmol·L -1 ) < HeLa (0 89 μmol·L -1 ) < BGC 823 (1 149 μmol·L -1 ) < PG (2 50 μmol·L -1 ). The scanning and transmission electron microscopy showed that the microvilli of HL 60 cell surface shortened, and the shape of HL 60 cells nuclei changed to kidney shaped, horse shoe shaped and bilob ated after treatment with 8 CA. Meanwhile, 8 CA promoted NBT reduction and increased activity of acid phosphatase in HL 60 cells in a time and concentration dependent manner. Flow cytometry analysis indicated that 8 CA induced an appreciable increase of the cell population in G 1 phase with a marked reduction in S phase. Conclusion 8 CA can induce differentiation of HL 60 cells and block the cells at G 1 phase, thus inhibiting proliferation of HL 60 cells.
