AIM： To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action.METHODS： The cytotoxic effect of alisol B acetate on SGC7901 cells was meas...AIM： To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action.METHODS： The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by 3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyltetrazolium bromide （MI-I-） assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential （A^Pm） were determined by flow cytometry. Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases （PI3K）.RESULTS： Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time- and dose-dependent manner. PI staining showed that alisol B acetate can change the cell cycle distribution of SGC7901, increase the proportion of cells in G0-G1 phase and decrease the proportion of S phase cells and G2-M phase cells. Alisol B acetate at a concentration of 30 pmol/L induced apoptosis after 24, 48 and 72 h incubation, with occurrence rates of apoptotic cells of 4.36%, 14.42% and 21.16%, respectively. Phase-contrast and electron microscopy revealed that the nuclear fragmentation and chromosomal condensed, cells shrank and attachment loss appeared in the SGC7901 treated with alisol B acetate. Apoptosis of SGC7901 cells was associated with cell cycle arrest, caspase-3 and caspase-9 activation, loss of mitochondrial membrane potential and up-regulation of the ratio of Bax/Bcl-2 and inhibition of the PI3K/Akt.CONCLUSION： Alisol B acetate exhibits an antiproliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways.展开更多
Over-expression of P-glycoprotein(P-gp),an ATP-dependent drug efflux pump,represents one of the major mechanisms that contribute to multidrug resistance(MDR) in cancer cells.This study examined the effects of troglita...Over-expression of P-glycoprotein(P-gp),an ATP-dependent drug efflux pump,represents one of the major mechanisms that contribute to multidrug resistance(MDR) in cancer cells.This study examined the effects of troglitazone,a ligand of peroxisome proliferator-activated receptor gamma(PPARγ),on P-gp-mediated MDR in SGC7901/VCR cells(a vincristine-resistant human gastric cancer cell line).The expression of P-gp was detected by RT-PCR and Western blotting,respectively.The SGC7901/VCR cells were treated with 0.1 mg/L vincristine(VCR) alone or in combination with 1,5,10 μmol/L troglitazone for 24 h.PPARγ was measured by electrophoretic mobility shift assay(EMSA).The intracellular concentration of Rhodamine123(Rh123,a fluorescent P-gp substrate) was assayed to evaluate the activity of P-gp.The cell cycle and apoptosis were measured by flow cytometry.The results showed that the P-gp was increasingly expressed in SGC7901,BGC823 and SGC7901/VCR cells in turn,suggesting that MDR in the SGC7901/VCR cells was mediated by the increased expression of P-gp.In the SGC7901/VCR cells,the expression level of total PPARγ was increased,however,the protein level and activity of PPARγ in the nuclei of cells decreased significantly.Troglitazone elevated the PPARγ activity in SGC7901/VCR cells in a dose-dependent manner.Troglitazone decreased the P-gp expression and markedly enhanced the accumulation of Rh123 in SGC7901/VCR cells in a dose-dependent manner.We also found that troglitazone significantly increased the percentage of SGC7901/VCR cells in the G2/M phase and decreased the cell percentage in G1 and S phase in a dose-dependent manner.Troglitazone significantly increased the apoptotic rate of SGC7901/VCR cells treated by VCR or ADR in a dose-dependent manner.It was concluded that P-gp-overexpressed SGC7901/VCR cells have minor endogenous PPARγ activity.Elevation of the PPARγ activity by troglitazone can reverse P-gp-mediated MDR via down-regulating the expression and activity of P-gp in SGC7901/VCR cells.It was suggested that troglitazone can dramatically enhance the sensitivity of P-gp-mediated MDR cancer cells to chemotherapeutic agents.展开更多
[Objectives]To observe the effect of drug-containing serum from different extracts of Phyllanthus reticulatus leaf on the proliferation of human gastric cancer SGC-7901 cells and the effect of in vivo on the life exte...[Objectives]To observe the effect of drug-containing serum from different extracts of Phyllanthus reticulatus leaf on the proliferation of human gastric cancer SGC-7901 cells and the effect of in vivo on the life extension rate of mice with H22 ascites tumor,and to investigate the effects of chemical components such as Corilagin,ethyl gallate,ethyl brevifolincarboxylate,and gallic acid on the proliferation of human gastric cancer SGC-7901 cells.[Methods]MTT method was used to observe the inhibitory effect of drug-containing serum of different extracts of P.reticulatus leaf on human gastric cancer SGC-7901 cells in vitro to determine its active site.The active site was used as the research object to establish a Kunming mouse ascites tumor model,to investigate the effect on the life extension rate of mice with H22 ascites tumor,to further separate the monomer components from the effective fraction and investigate its effect on human gastric cancer SGC-7901 cells.[Results]Compared with the 10%blank serum control group,10%drug-containing serum of ethyl acetate and n-butanol in P.reticulatus leaf had significant inhibitory effect on the proliferation of human gastric cancer SGC-7901 cells,and the inhibition rate was 34.99%and 28.68%,respectively(P<0.05).Compared with the blank group,the survival time of the high dose group of ethyl acetate in P.reticulatus leaf was significant(P<0.05).Gallic acid,Corilagin,and Brevifolincarboxylic acid ethyl ester had a significant inhibitory effect on the proliferation of human gastric cancer SGC-7901 cells,with IC 50 of 26.52,70.45,and 158.86μg/mL,respectively.Ethyl gallate had no inhibitory effect on the proliferation of human gastric cancer SGC-7901 cells,and its IC 50 was 251.96μg/mL.[Conclusions]The drug-containing serum of ethyl acetate and n-butanol extract of P.reticulatus can inhibit the proliferation of human gastric cancer SGC-7901 cells.Ethyl acetate of P.reticulatus leaves can increase the life extension rate of mice with H22 ascites tumor.Gallic acid,Corilagin,and Brevifolincarboxylic acid ethyl ester isolated from its active site are the material basis for inhibiting the proliferation of human gastric cancer SGC-7901 cells.展开更多
AIM： To detect the biological characters of the SGC7901 gastric cancer cell-dendritic cell fusion vaccines.METHODS： The suspending living SGC7901 gastric cancer cells and dendritic cells were induced to be fusioned ...AIM： To detect the biological characters of the SGC7901 gastric cancer cell-dendritic cell fusion vaccines.METHODS： The suspending living SGC7901 gastric cancer cells and dendritic cells were induced to be fusioned by polyethylene glycol. Pure fusion cells were obtained by selective culture with the HAT/HT culture systems. The fusion cells were counted at different time points of culture and their growth curves were drawn to reflect their proliferative activities. The fusion cells were also cultured in culture medium to investigate whether they could grow into cell clones. MTT method was used to test the stimulating abilities of the fusion cells on T lymphocytes＇ proliferations. Moreover, the fusion cells were planted into nude mice to observe whether they could grow into new planted tumors in this kind of immunodeficiency animals.RESULTS： The fusion cells had weaker proliferative activity and clone abilities than their parental cells. When they were cultured, the counts of cells did not increase remarkably, nor could they grow into cell clones in culture medium. The fusion cells could not grow into new planted tumors after planted into nude mice. The stimulating abilities of the fusion cells on T lymphocytes＇ proliferations were remarkably increased than their parental dendritic cells. CONCLUSION： The SGC7901 gastric cancer cell-dendritic cell fusion vaccines have much weaker proliferative abilities than their parental cells, but they keep strong abilities to irritate the T lymphocytes and have no abilities to grow into new planted tumors in immunodeficiency animals. These are the biological basis for their antitumor biotherapies.展开更多
Objective: To research the inhibitory effect on SGC-7901 cells of α-pinene, and the related mechanism of α-pinene. Methods: Used the MTT method to detect inhibition rate and western blotting to detect the influence ...Objective: To research the inhibitory effect on SGC-7901 cells of α-pinene, and the related mechanism of α-pinene. Methods: Used the MTT method to detect inhibition rate and western blotting to detect the influence on expression of ATM, Phos-S1981ATM, H2AX, γH2AX, CHK2 and p-CHK2, p53 and phos-p53 cell cycle related protein in SGC-7901 cells. Results: The research found α-pinene could inhibit the proliferation of SGC-7901 cells observably in vitro, and the inhibition rate assumes the dependence on concentration;and western blotting results showed that, α-pinene could activate phospho-ATM, increase the amount of γH2AX (p p < 0.05);increase the expression of p-CHK2, p53 and phos-p53 (p p p < 0.05);But there is no significant effect on expression of CHK2 (p > 0.05). Conclusions: α-pinene could inhibit the proliferation of SGC-7901 cells, and by inducing ATM (Ataxia Telangiectasia-Mutated) kinase signal pathway in DNA damage response, activating cell cycle checkpoint, making the cell cycle arrest then exerts its anti-tumor effects.展开更多
文摘AIM： To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action.METHODS： The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by 3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyltetrazolium bromide （MI-I-） assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential （A^Pm） were determined by flow cytometry. Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases （PI3K）.RESULTS： Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time- and dose-dependent manner. PI staining showed that alisol B acetate can change the cell cycle distribution of SGC7901, increase the proportion of cells in G0-G1 phase and decrease the proportion of S phase cells and G2-M phase cells. Alisol B acetate at a concentration of 30 pmol/L induced apoptosis after 24, 48 and 72 h incubation, with occurrence rates of apoptotic cells of 4.36%, 14.42% and 21.16%, respectively. Phase-contrast and electron microscopy revealed that the nuclear fragmentation and chromosomal condensed, cells shrank and attachment loss appeared in the SGC7901 treated with alisol B acetate. Apoptosis of SGC7901 cells was associated with cell cycle arrest, caspase-3 and caspase-9 activation, loss of mitochondrial membrane potential and up-regulation of the ratio of Bax/Bcl-2 and inhibition of the PI3K/Akt.CONCLUSION： Alisol B acetate exhibits an antiproliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways.
基金supported by grants from Natural Sciences Foundation of Hubei Province (No.2007ABA065)Science and Technology Key Project of Health Bureau of Hubei Province (No.JX1B006)
文摘Over-expression of P-glycoprotein(P-gp),an ATP-dependent drug efflux pump,represents one of the major mechanisms that contribute to multidrug resistance(MDR) in cancer cells.This study examined the effects of troglitazone,a ligand of peroxisome proliferator-activated receptor gamma(PPARγ),on P-gp-mediated MDR in SGC7901/VCR cells(a vincristine-resistant human gastric cancer cell line).The expression of P-gp was detected by RT-PCR and Western blotting,respectively.The SGC7901/VCR cells were treated with 0.1 mg/L vincristine(VCR) alone or in combination with 1,5,10 μmol/L troglitazone for 24 h.PPARγ was measured by electrophoretic mobility shift assay(EMSA).The intracellular concentration of Rhodamine123(Rh123,a fluorescent P-gp substrate) was assayed to evaluate the activity of P-gp.The cell cycle and apoptosis were measured by flow cytometry.The results showed that the P-gp was increasingly expressed in SGC7901,BGC823 and SGC7901/VCR cells in turn,suggesting that MDR in the SGC7901/VCR cells was mediated by the increased expression of P-gp.In the SGC7901/VCR cells,the expression level of total PPARγ was increased,however,the protein level and activity of PPARγ in the nuclei of cells decreased significantly.Troglitazone elevated the PPARγ activity in SGC7901/VCR cells in a dose-dependent manner.Troglitazone decreased the P-gp expression and markedly enhanced the accumulation of Rh123 in SGC7901/VCR cells in a dose-dependent manner.We also found that troglitazone significantly increased the percentage of SGC7901/VCR cells in the G2/M phase and decreased the cell percentage in G1 and S phase in a dose-dependent manner.Troglitazone significantly increased the apoptotic rate of SGC7901/VCR cells treated by VCR or ADR in a dose-dependent manner.It was concluded that P-gp-overexpressed SGC7901/VCR cells have minor endogenous PPARγ activity.Elevation of the PPARγ activity by troglitazone can reverse P-gp-mediated MDR via down-regulating the expression and activity of P-gp in SGC7901/VCR cells.It was suggested that troglitazone can dramatically enhance the sensitivity of P-gp-mediated MDR cancer cells to chemotherapeutic agents.
基金Supported by Natural Science Research Project of Guangxi University of Chinese Medicine in 2015"Study on Anti-tumor Effect of Phyllanthus reticulatus Leaf Extract"(p15028)Independent Research Program of Guangxi Key Laboratory of Traditional Chinese Medicine Pharmacology in 2015"Study on Phyllanthus reticulatus Leaf 7404 Nude Mice Xenografts"+1 种基金Young Teachers Enhancement Project of Guangxi Department of Education in 2018"Study on the Mechanism of Zhuang Medicine Phyllanthus reticulatus Leaf against Liver Cancer"(2018KY0300)2019-2021 Guangxi First-class Discipline Construction Open Project Fund for Young Scholars of Guangxi University of Chinese Medicine"Anti-hepatocarcinoma Mechanism of Autophagy Induced by Ethyl Acetate in Phyllanthus reticulatus Leaf Based on PI3K/AKT and STAT3/m TOR Signaling Pathway"(2019XK089)
文摘[Objectives]To observe the effect of drug-containing serum from different extracts of Phyllanthus reticulatus leaf on the proliferation of human gastric cancer SGC-7901 cells and the effect of in vivo on the life extension rate of mice with H22 ascites tumor,and to investigate the effects of chemical components such as Corilagin,ethyl gallate,ethyl brevifolincarboxylate,and gallic acid on the proliferation of human gastric cancer SGC-7901 cells.[Methods]MTT method was used to observe the inhibitory effect of drug-containing serum of different extracts of P.reticulatus leaf on human gastric cancer SGC-7901 cells in vitro to determine its active site.The active site was used as the research object to establish a Kunming mouse ascites tumor model,to investigate the effect on the life extension rate of mice with H22 ascites tumor,to further separate the monomer components from the effective fraction and investigate its effect on human gastric cancer SGC-7901 cells.[Results]Compared with the 10%blank serum control group,10%drug-containing serum of ethyl acetate and n-butanol in P.reticulatus leaf had significant inhibitory effect on the proliferation of human gastric cancer SGC-7901 cells,and the inhibition rate was 34.99%and 28.68%,respectively(P<0.05).Compared with the blank group,the survival time of the high dose group of ethyl acetate in P.reticulatus leaf was significant(P<0.05).Gallic acid,Corilagin,and Brevifolincarboxylic acid ethyl ester had a significant inhibitory effect on the proliferation of human gastric cancer SGC-7901 cells,with IC 50 of 26.52,70.45,and 158.86μg/mL,respectively.Ethyl gallate had no inhibitory effect on the proliferation of human gastric cancer SGC-7901 cells,and its IC 50 was 251.96μg/mL.[Conclusions]The drug-containing serum of ethyl acetate and n-butanol extract of P.reticulatus can inhibit the proliferation of human gastric cancer SGC-7901 cells.Ethyl acetate of P.reticulatus leaves can increase the life extension rate of mice with H22 ascites tumor.Gallic acid,Corilagin,and Brevifolincarboxylic acid ethyl ester isolated from its active site are the material basis for inhibiting the proliferation of human gastric cancer SGC-7901 cells.
文摘AIM： To detect the biological characters of the SGC7901 gastric cancer cell-dendritic cell fusion vaccines.METHODS： The suspending living SGC7901 gastric cancer cells and dendritic cells were induced to be fusioned by polyethylene glycol. Pure fusion cells were obtained by selective culture with the HAT/HT culture systems. The fusion cells were counted at different time points of culture and their growth curves were drawn to reflect their proliferative activities. The fusion cells were also cultured in culture medium to investigate whether they could grow into cell clones. MTT method was used to test the stimulating abilities of the fusion cells on T lymphocytes＇ proliferations. Moreover, the fusion cells were planted into nude mice to observe whether they could grow into new planted tumors in this kind of immunodeficiency animals.RESULTS： The fusion cells had weaker proliferative activity and clone abilities than their parental cells. When they were cultured, the counts of cells did not increase remarkably, nor could they grow into cell clones in culture medium. The fusion cells could not grow into new planted tumors after planted into nude mice. The stimulating abilities of the fusion cells on T lymphocytes＇ proliferations were remarkably increased than their parental dendritic cells. CONCLUSION： The SGC7901 gastric cancer cell-dendritic cell fusion vaccines have much weaker proliferative abilities than their parental cells, but they keep strong abilities to irritate the T lymphocytes and have no abilities to grow into new planted tumors in immunodeficiency animals. These are the biological basis for their antitumor biotherapies.
文摘Objective: To research the inhibitory effect on SGC-7901 cells of α-pinene, and the related mechanism of α-pinene. Methods: Used the MTT method to detect inhibition rate and western blotting to detect the influence on expression of ATM, Phos-S1981ATM, H2AX, γH2AX, CHK2 and p-CHK2, p53 and phos-p53 cell cycle related protein in SGC-7901 cells. Results: The research found α-pinene could inhibit the proliferation of SGC-7901 cells observably in vitro, and the inhibition rate assumes the dependence on concentration;and western blotting results showed that, α-pinene could activate phospho-ATM, increase the amount of γH2AX (p p < 0.05);increase the expression of p-CHK2, p53 and phos-p53 (p p p < 0.05);But there is no significant effect on expression of CHK2 (p > 0.05). Conclusions: α-pinene could inhibit the proliferation of SGC-7901 cells, and by inducing ATM (Ataxia Telangiectasia-Mutated) kinase signal pathway in DNA damage response, activating cell cycle checkpoint, making the cell cycle arrest then exerts its anti-tumor effects.
