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Objective To study the effect of heat stress on the permeability,cytoskeleton and cell cycle of human skeletal muscle cell (HSKMC).Methods The HSKMC membrane permeability was detected by calcium ion inflow with flow cytometer,the cytoskeleton was stained by CBB 250,and the cell cycle was determined by flow cytometer.Results After 1 h of heat stress on human HSKMC cells under different temperature gradient,the median level of calcium ion was 91.63 in 43 ℃ heat stress group compared with 22.98 in 37 ℃ control group.As temperature increased,thicker and shorter cytoskeleton and stress fiber were shown under the high power lens of microscope.The DNA expression of skeleton cells at G0/G1 stage was 44.13-62.98 in groups under heat stress.Compared with normal control group,DNA expression was much higher in heat stress group,when HSKMC was cultured under 37 ℃ temperature for another 18 h,it kept decreasing DNA expression to a similar level as control group.Conclusions Heat stress can cause calcium iron inflow resulting in intracellular calcium overload,and affect the cytoskeleton leading to loss of normal web ordered arrangement and increased gap in HSKMC cells,which give rise to blocking cell cycle into G0/G1 stage.
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Objective: To investigate the effects of VPA (valproate) on proliferation, cell cycle distribution and apoptosis of human kidney carcinoma ACHN cells and the possible underlying mechanisms. Methods: The effect of VPA on the proliferation of ACHN cells was examined by CCK-8 (cell counting kit-8) assay. Flow cytometry was used to analyze the cell cycle distribution and apoptosis of ACHN cells exposed to VPA. The mRNA expressions of cyclin E1, P 21WAF1, Bcl-2 and Bax were detected by real-time fluorescence quantitative-PCR. Results: Incubation with various concentrations of VPA for 48 h resulted in a significant inhibition of proliferation of ACHN cells with an IC50 (50% inhibitory concentration) value of 4.21 mmol/L. After treatment with VPA, the cell cycle was arrested obviously at G 0/G1 phase and the apoptotic rate was significantly increased as compared with the control group. After treatment with 4 mmol/L VPA for 48 h, the levels of P21WAF1 and Bax mRNAs were both significantly increased, and at the same time, the levels of cyclin E1 and Bcl-2 mRNAs were obviously decreased. Conclusion: VPA can inhibit the proliferation of kidney carcinoma ACHN cells by inducing cell-cycle arrest and apoptosis. Copyright © 2013 by TUMOR.
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Objective To investigate the effects of HIF-1α expression regulated by Tet-on gene expression system on cell proliferation and cell cycle of hepatoma cells in vitro. Methods The change of human hepatocellular carcinoma cell lines HepG2 cell cycle and cell proliferation was measured after HIF-1 α expression of HepG2 in vitro was regulated by Tet-on expression system. Results Amplified products were confirmed as the cDNA of HIF-1α by DNA sequencing, and pTRE-HIF-1α obtained by edonuclease digestion,capable of expression in HepG2 Tet-on cells. After being incubated under different concentrations of doxycycline for 48 h, MTT assays showed that up-regulation of HIF-1α expression increased HepG2 cell proliferation activities. The cell index of S and G2/M phase was significantly higher and that of G0/G1 phase reduced with the increasing concentrations of doxycycline. The mRNA expression of Cyclin A increased with the increasing concentrations of doxycycline ( P ＜ 0. 001 ), CyclinD1 and CyclinE did not change ( P ＞0. 05). Conclusion HIF-1 α gene promotes cell proliferation and cell cycle of hcpatoma cells in vitro, and this effects increased with the increasing of HIF-1α expression possibly through influencing the expression of CyclinA.
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Objective To evaluate effects of trichostain A (TSA) on cell proliferation, cell cycles, apoptosis and invasiveness of multiple myeloma cell line U266; as well as active changes of methylation regulating proteins including DNA methyl-transferase(DNMTs), methyl-binding domain (MBD) proteins: MBD2 and MeCP2 after treated with TSA. Methods U266 cells were treated with different concentrations of TSA for 12, 24, 48 and 60 h. The proliferation activity of U266 cells was detected by MTT and the IC50 of 24 h was calculated. After U266 cells were treated with IC50, cell cycles were check out by dying with PI. mRNA of matrix metalloproteinase-2(MMP-2), bc1-2, bcl-xl and methylation regulating proteins (DNMTs, MBD2 and MeCP2) were detected by real-time PCR. FCM and Western blotting were used to measure expressions of MMP-2 and MBD2. Results MTT results revealed TSA inhibited proliferation of U266 cells in a dose-and time-dependent manner and the IC50 of 24 h was 0.07 μmol/L FCM analysis showed that TSA could arrest the cell cycle in G0/G1 and the proliferation index (PI) in U266 cells [(49.90 0.39)%]were significantly different after exposed to TSA (0.7 μmnol/L for 24h compared with that in the control cells[(55.78 0.49)%](P <0.01). After treated by TSA, the 2-△△Ct of MMP-2, bcl-2 and bcl-xl were 0.71 0.06, 5.04 0.92 and 2.95 0.35, respectively. There were great changes on mRNA of DNMT, MBD2 and MeCP2. TSA could reverse the transcription of DNMT, MBD2 and MeCP2. Conclusion TSA can arrest the U266 cell cycle in GVG, to prevent its proliferation and promote apoptosis, which maybe greatly connect with the changes of the methylation regulating proteins.
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AIM To study the antitumor activity of astragalosides(AST) and its mechanism of action. METHODS By using two experimental models of hepatoma(HepA) and Sarcoma 180 in mice, the rate of inhibition of tumor weight AST on the growth of HepA and S180 tumor cells were tested. The growth inhibition of AST on Hela cells was detected by MTT assay. The effect of AST on cell cycle and apoptosis was analyzed by flow cytometry and TUNEL. RESULTS AST inhibited the growth of tumor cells of HepA and S180 in mice. AST inhibited the growth of Hela cell in concentration dependent manner with IC 50 of 80 4 mg?L -1 . Flow cytomety analgsis showed that G 0/G 1 phase rate was increased but S phase rate was decreased. The apoptosis rate of Hela cells treated with AST( 80 and 160 mg?L -1 ) was significantly higher than that of control. CONCLUSION AST can inhibit the growth of tumor cells of HepA and S180 in mice and the growth of HeLa cells in vitro . Causing cell cycle arrest and apoptosis is probably one of the mechanisms of antitumor effect by AST.
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Objective To investigate the transfection of human papilloma virus types 16E6 gene on the proliferation and apoptosis of cervical carcinoma cell line C33A. MethodsPlasmid pcDNA3-HPV16E6 was stably transfected into C33A cells by liposome, and the expression of HPV16E6 mRNA and protein in the transfected cells, the cells transfected with blank vector and the cells without transfection were identified by RT-PCR and Western blot analysis. The growth, proliferation and cell cycles of the 3 kinds of C33A cells were by cell growth curve plotting and flow cytometry analysis. ResultsC33A cells were transfected stably by liposome with plasmid pcDNA3-HPV16E6 (C33A-E6 cells)and plasmid pcDNA3 (C33A-P cells). The growth of C33A-E6 cells was more rapid than those of C33A-P and C33A cells (P0.05). ConclusionHPV16E6 is involved in the cell cycle probably through some signal pathways, and promotes cell division and proliferation of C33A cells.
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Objective Effect of baohuoside-Ⅰ from Cortex Periplocae on cell cycle of human esophageal carcinoma cell Eca-109 and its mechanism were studied.Methods After treatment with baohuoside-Ⅰ at different concentration(12.5,25,and 50 ?g/mL)for 24,48,and 72 h,the inhibitory effect on proliferation of Eca-109 cells was analyzed by MTT method.After treatment with baohuoside-Ⅰ under different concentration(12.5,25,and 50 ?g/mL)for 48 h,cell cycle of Eca-109 cells were measured with flow cytometry(FCM);The expression of Cyclin B1 mRNA was detected by RT-PCR technique.The expression of Cyclin B1 protein was detected by Western blotting.Results Baohuoside-Ⅰ of 25 and 50 ?g/mL inhibited the proliferation of Eca-109 cells significantly in an effect-concentration manner(P
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Objective To evaluate the prognosis of laryngeal cancer postoperative recurrence, and to investigate the relationship of Cyclin D1, PCNA, and Ki 67 protein expression in patients with recurrent laryngeal carcinoma. Methods 574 cases of laryngeal carcinoma from 1958 to 1999 were retrospectively reviewed. All patients were follow up surveyed for 3 years postoperatively. The whole set of tissue microarrays from 574 patients contained tumor tissue, including recurrent tumor tissue from 56 patients, and 39 normal laryngeal tissue specimens from normal laryngeal were collected as control. The tissue chips were analyzed by the SABC immunohistochemical method. Results Cyclin D1, PCNA, and Ki 67 expressed in most of the laryngeal carcinoma and normal laryngeal tissues in a different positive ratio. There was higher expression of Cyclin D1, PCNA, and Ki 67 in recurrent laryngeal carcinoma compared to that in laryngeal carcinoma without recurrence and normal laryngeal tissue ( P