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Objective To investigate the expression of mitogen-activated protein kinase kinase 1 (MAP2K1) in gastric cancer and its clinical significance. Methods Immunohistochemistry and Western blotting were used to detect the protein expression of MAP2K1 in gastric cancertissues and cells. The morphology and the expression position of MAP2K1 were observed by immunofluorescence. MAP2K1 mRNA expression in gastric cancer tissues was analyzed by data mining of Starbase database and Oneomine database. The correlation between MAP2K1 mRNA expression and clinicopathological features was analyzed by UALCAN database. Survival analysis was performed using Kaplan Meier-Plotter online analysis tools. GEPIA2 database mining the relationship between MAP2K1 and gastric cancer stem cell related factors and drug resistance related factors. Results Immunohistochemistry, immunofluorescence and Western blotting showed that MAP2K1 protein was highly expressed in gastric cancer tissues and cells, and MAP2K1 was expressed in the cytoplasm of gastric cancer. According to the analysis of various databases, the expression of MAP2K1 mRNA in gastric cancer tissue was higher than that in normal gastric tissue, and the expression of MAP2K1 mRNA was closely related to gastric cancer stage, grade, lymph node metastasis and patient gender, and the overall survival rate of gastric cancer patients in the group with high MAP2K1 mRNA expression was significantly lower than that in the group with low MAP2K1 mRNA expression, which may be related to the characteristics of gastric cancer stem cells and drug resistance. Conclusion MAP2K1 is highly expressed in gastric cancer, and its expression level may affect the poor prognosis of patients by regulating stem cell related factors and drug resistance related factors. MAP2K1 may be a new diagnostic marker to determine the prognosis of gastric cancer patients.
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【Objective】 To investigate the effects of RASSF6 gene on gastric cancer cells’ proliferation， autophagy， apoptosis， and sensitivity to oxaliplatin chemotherapy. 【Methods】 Gastric cancer BGC823 cells were cultured in vitro and divided into experimental control group （control group）， RASSF6 overexpression group （Oe group）， RASSF6 interference group， and lentivirus control group according to the expression effect of lentivirus gene. The changes in cell proliferation， cell cycle distribution， cell migration， autophagy， apoptosis and sensitivity to oxaliplatin in each group were detected， and the number of autophagy bodies in each group was detected by electron microscopy. Real-time PCR （qRT-PCR） and Western blotting were used to detect the expression levels of apoptosis- and autophagy-related genes in each group. 【Results】 Studies on the biological behavior of gastric cancer BGC823 cells induced by RASSF6 gene expression showed that compared with the control group， the percentage of G0/G1 phase cells in the Oe group increased， while the percentage of G2 and S phase cells decreased， with statistical significance （P<0.05）. The apoptosis rate was significantly increased （P<0.05）. The cell scratch assay showed that the scratch healing rate was significantly decreased （P<0.05）. Studies on the sensitivity of RASSF6 gene expression to oxaliplatin showed that compared with the drug group （L-OHP group）， the apoptosis rate of Oe+L-OHP group was increased significantly （P<0.05）. In the Oe+L-OHP group， the expression of anti-apoptotic protein Bcl-2 decreased， the expressions of Bax and Caspase-3 were increased； the expression of autophagosomes was increased； the expressions of Beclin-1 and P62 and the ratio of LC3-Ⅱ/LC3 were all increased （P<0.05）. 【Conclusion】 The RASSF6 gene plays a role in suppressing gastric cancer cell BGC823， which can increase the sensitivity to oxaliplatin chemotherapy by promoting apoptosis and autophagy.
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Objective:To define the anti-gastric cancer activity in vitro of petroleum ether fraction of Boehmeria nivea root and reveal the material basis of its efficacy, so as to lay the foundation for the development and utilization of B. nivea root. Method:Methyl thiazolyl tetraolium(MTT) method was used to evaluate the inhibitory rate and time-dose relationship of petroleum ether fraction of B. nivea root with different doses and delivery times on human gastric cancer HGC-27 cells. Flow cytometry was used to detect the change of cell apoptosis and cell cycle after petroleum ether fraction of B. nivea root acted on human gastric cancer HGC-27 cells. GC-MS was used to detect the components of petroleum ether fraction of B. nivea root. Result:Experiment data showed significant cell proliferation inhibition in an obvious time-dose-effect manner, with statistically significant differences (PB. nivea root. The effect of petroleum ether fraction of B. nivea root on human gastric cancer HGC-27 cells could induce apoptosis,which affects the normal changes of cell cycle. The percentage of cells was decreased significantly in G0/G1 phase,and that in S phase was significantly increased. GC-MS was used to identify 26 chemical constituents in petroleum ether of B. nivea root,including sitosterol and stigmasterol. Conclusion:Petroleum ether fraction of B. nivea root is the active anti-gastric cancer part,and its main effective component is sterol compounds. This lays the foundation for the rational application of B. nivea root in clinic and the further research in tis anti-tumor effect.
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@# Objective: To observe the effect of ursolic acid (UA) on autophagy and apoptosis of gastric cancer cell line MGC-803, and to explore the mechanism of UA-induced autophagy of MGC-803 cells based on PI3K/AKT/mTOR signaling pathway. Methods: Human gastric cancer cell line MGC-803 was cultured in vitro and divided into blank control group, UAintervention group and UA+3-MA group. The cell apoptosis in each group was detected by flow cytometry. Cell autophagy was detected by double fluorescence mRFPeGFP-LC3 plasmid transfection method. The mRNA expression levels of LC3B, BAX and Bcl-2 were detected by qPCR. The protein expression levels of PI3K type I, p-AKT, p-mTOR, ULK1, LC3B, BAX and Bcl-2 were detected by WB. Results: Flow cytometry showed that the cell apoptotic rate of UA intervention group was significantly higher than that of blank control group (P<0.05). Compared with UAintervention group, the apoptotic rate in UA+ 3-MAgroup was significantly reduced (P<0.05). The double fluorescence mRFP-eGFP-LC3 plasmid transfection method showed that the green and red fluorescent bright spots in UA intervention group increased significantly compared with the blank control group (P<0.05), and the green and red fluorescent bright spots in UA+3-MA group were significantly reduced compared with UA intervention group (P<0.05). Real-time quantitative PCR and WB method showed that compared with the blank control group, the mRNAand protein expressions of BAX and LC3B, and ULK1 protein were significantly increased in UA intervention group, while the mRNA and protein expressions of Bcl-2, and the protein expressions of PI3K, p-AKT and p-mTOR were significantly decreased in UA intervention group (all P<0.05); Compared with UA intervention group, mRNA and protein expressions of BAX and LC3B were significantly down-regulated and the mRNAand protein expressions of Bcl-2 were significantly up-regulated in UA+3-MA group (all P<0.05), while protein levels of PI3K, p-AKT, p-mTOR and ULK1 were not significantly changed in UA+3-MA group (P>0.05). Conclusion: UA can promote apoptosis of MGC-803 cells via inducing autophagy, which may be related to UA's involvement in regulating the expressions of PI3K/AKT/mTOR signaling pathway-related proteins.
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Objective To investigate whether miR?485?3p plays a role in regulation of radiosensitivity of gastric cancer cells by targeting TLR1. Methods Quantitative real?time PCR and Western blot were used to determine the expression of miR?485?3p and TLR1, respectively. The interaction between miR?485?3p and TLR1 was verified by target prediction software ( DIANA, TargetScan, and miRanda) and dual luciferase reporter assay. Gastric cancer MGC803 cells transfected with miR?485?3p mimic or TLR1 siRNA were exposed to irradiation. Apoptosis assay, colony formation assay, and MTT assay were used to evaluate the changes in radiosensitivity of gastric cancer cells. Dual luciferase reporter assay was used to determine the effects of miR?485?3p overexpression and TLR1 silencing on the activity of NF?κB. Western blot was used to study the effects of miR?485?3p overexpression and TLR1 silencing on NF?κB target genes. Results In gastric cancer cells exposed to radiation, the expression of miR?485?3p was downregulated and the expression of TLR1 was upregulated. TLR1 was predicted to be the target of miR?485?3p by target prediction software. Dual luciferase reporter assay further confirmed TLR1 as the direct target of miR?485?3p. miR?485?3p negatively regulated the expression of TLR1. The overexpression of miR?485?3p, as well as TLR1 silencing, increased the apoptosis rate of cells, reduced colony formation and cell proliferation, and enhanced the radiosensitivity of the cells. Both miR?485?3p overexpression and TLR1 silencing reduced the activity of NF?κB and downregulated the expression of multiple NF?κB target genes. Conclusions miR?485?3p enhances the radiosensitivity of gastric cancer cells probably by targeting TLR1 and regulating the NF?κB signaling pathway.
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OBJECTIVE:To investigate the effects of Ginkgo biloba extract (GBE) on proliferation and apoptosis of gastric cancer cell line SGC7901. METHODS:After the cells were cultured in 0,5,10,20,50,100 and 200 μg/ml GBE for 48 h,cell viability was determined by MTT method and inhibition rate was calculated. After the cells were cultured in 0,10,50 and 200μg/ml GBE for 48 h,flow cytometry was used to detect cell cycle distribution and the apoptosis rate. RESULTS:Following 48 h culture of cells in 5,10,20,50,100 and 200μg/ml GBE,the growth of cells were obviously inhibited in a dose-dependent man-ner. After 48 h culture of cells in 10,50 and 200 μg/ml GBE,the apoptosis rate was increased. CONCLUSIONS:GBE can inhibi-tion the proliferation of SGC7901,and induces it apoptosis,the former dominated.
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ABSTRACT:Objective To investigate the effects of ω-3 polyunsaturated fatty acids on the proliferation of human gastric cancer cell line AGS and the possible mechanisms.Methods Human gastric cancer line AGS and human microvascular epithelial cell HMEC-1 were treated with different concentrations of docosdhexaenoic acid (DHA)and eicosapentaenoic acid (EPA).The inhibition of cell proliferation was evaluated by MTT assay and cell morphology.Flow cytometry was used to detect the cell cycle change.The expressions of mitochondrial respiratory membrane protein complex Ⅰ,Ⅱ and V were analyzed with Western blot.Results DHA and EPA could markedly inhibit the proliferation of AGS in significant time-dependent and concentration-dependent manners (P 0.05).Conclusion ω-3 PUFAs can selectively inhibit the growth and proliferation of human gastric cancer cell line AGS.These effects may be as-sociated with arresting cell cycle in G0/G1 phase and inhibiting the energy metabolism of AGS cells.
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This study was aimed to investigate effect of aconite alkaloids on proliferation and apoptosis of hu-man gastric cancer cell line SGC-7901 . Effects of different concentrations of aconite alkaloids on proliferation of human gastric cancer cell line SGC-7901 were investigated with MTT assay; induced apoptosis and cell cy-cle blocking were detected with flow cytometer ( FCM ) . The results showed that the IC50 of aconite alkaloids on human gastric cancer cell line SGC-7901 was 0 . 2318 ± 0 . 0022 , 0 . 1601 ± 0 . 0227 , 0 . 1031 ± 0 . 0231 mg/ml at 24 h , 48 h and 72 h , respectively , compared to the control group with significant difference ( P <0.01). When the aconite alkaloids concentration was 0.8 mg/ml, it appeared with obvious apoptosis. The apop-tosis rate was ( 59 . 38 ± 5 . 05 )%. The FCM detection showed that compared with control group , the percentage of S-phase cells increased in the treatment group . And a typical sub-diploid peak appeared before G0 / G1 phase . It was concluded that aconite alkaloids can inhibit the proliferation of human gastric cancer cell line SGC-7901 in vitro, induce the apoptosis of cells and make SGC-7901 cells remain in S phase.
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OBJECTIVE: To investigate the effect of galangin on the anti-proliferation and apoptosis of gastric cancer SGC-7901 cells, and possible mechanisms. METHODS: Proliferative activity of SGC-7901 cells was measured by MTT assay while that cell cycle progression and apoptosis of galangin-treated SGC-7901 cells were analyzed by flow cytometry, morphologic observation and mitochondrial membrane potential (MMP) analysis. RESULTSS The evaluated results showed that when galangin was added into cell culture in 40-200 μmol · L-1, proliferative inhibition occurred and was observed as a dose- and time-dependent manner. The calculated IC50 values for galangin were 160, 100 and 70 μmol · L-1 when the treatment time was 24, 48 and 72 h, respectively. Flow cytometry analysis revealed that the proportion of the cells in the G2/M phase was significantly enhanced from 4.40(control group) to 18.31 (treatment group) by a treatment time of 24 h. CONCLUSION: The cells in treatment group showed typical apoptotic morphology and a decrease in MMP. At the same time, the percentage of the apoptotic cells significantly increased from 2.6% or 4.3% (control group) to 27.4% or 65.6% (treatment group), when 160 μmol · L-1 galangin treated SGC-7901 cells for 24 or 48 h. These mentioned results indicate that galangin can inhibit the proliferation and induce apoptosis of the SGC-7901 cells by perturbation in cell cycle progression and mitochondrial dysfunction.
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ObjectiveTo observe the effect of betulinic acid(BetA) on the growth of human cytokine induced killer(CIK) cells and the killing activity of CIK cells on the gastric cancer cells in vitro before and after induced by betulinic acid,explore its mechanism.MethodsPeripheral blood mononuclear cell (PBMC) were separated form the healthy and were induced with various of cytokine to become CIK cells in vitro.CIK cells were collected on the tenth day and were induced with betulinic acid in different concentrations,followed by 48 h,the colorimetric methyl thiazolyl tetrazolium(MTT) method assay the proliferation rate of human CIK cells.Flow cytometry (FCM) was used to detect the expression changes of perforin,granzyme B and CD107a of human CIK cells before and after betulinic acid-induced.Lactate dehydrogenase (LDH) release assay was used to measure the influence on cytotoxic activity of CIK cells induced by betulinic acid against gastric cancer cell line SGC-7901 in vitro.Western blot assay was used to measure the extracellular signal-regulated kinase1/2 (ERK1/2),and adapter proteins SH2-domain containing leukocyte protein of 76KD(SLP-76) and linker for activative of T cells(LAT) expression changes of human CIK cells before and after drug-induced.ResultsBetulinic acid can promote CIK cells growth when the concentration were in 0.08-10 μg/ml,the expression of perforin,granzyme B and CD107a of CIK cells were significantly higher than control group(P＜0.05) when the concentration of betulinic acid were in 0.3 μg/ml.In the meanwhile,the cytotoxic activity of CIK cells in vitro against gastric cancer cell line SGC-7901 were also remarkably higher than the control group (P＜0.05).The expression of SLP-76,LAT and ERK1/2 were significantly increased to a certain extent than the control group( P＜0.05 ),when CIK cells were treated with betulinic acid.ConclusionThese results suggest that betulinic acid can promote CIK cells growth in some concentrations and increase the cytotoxic activity of CIK cells against gastric cancer cell line SGC-7901,its mechanism may related with two factors,on the one hand,enhancing the activity of SLP-76,LAT and ERK1/2,on the other hand,increasing the expression of perforin,granzyme B and CD107a on the surface of CIK cells.
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PURPOSE: Diallyl disulfide (DADS) is a major organosulfur compound derived from garlic. It has been reported that DADS is able to inhibit the proliferation of several tumor cells. In this study, the effect of DADS was investigated in terms of the proliferation of AGS, gastric adenocarcinoma cell line at various concentrations. METHODS: The viability of cultured cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. To detect the induction of apoptosis, Annexin V-FITC/propodium iodide (PI) staining assay was performed. Analysis of reactive oxygen species (ROS) and the distribution of cells in the cell cycle were measured by a flow cytometer. And using the Western blot analysis, the change of Fas, caspase-3, Bax, Bcl-2 activity was measured. RESULTS: The percentage of live AGS cells was decreased to 23% of that in the control group after 400 microM DADS treatment for 48 hours. The Annexin V positive/PI negative (apoptosis portion) area increased from low concentration of DADS to high concentration. When comparing among the DADS treatment groups, the amount of ROS production increased in a dose dependent manner. The percentage of sub-diploid DNA content increased from 8.71% at 50 microM to 25.74% at 400 microM DADS treatment group. The expressions of Fas, caspase-3, Bax were increased and that of Bcl-2 was decreased in a dose dependent manner. CONCLUSION: DADS decreases the viability of AGS cell lines and induces apoptosis in a dose-dependent manner. But the relationship of the anti-proliferative effect of DADS and related molecular changes were not clearly proportional to the concentration of DADS.
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4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid , Adenocarcinoma , Allyl Compounds , Annexin A5 , Apoptosis , Blotting, Western , Caspase 3 , Cell Cycle , Cell Line , Cells, Cultured , Disulfides , DNA , Garlic , Reactive Oxygen Species , Stomach NeoplasmsABSTRACT
Objective To investigate the effects of ginsenoside Rg3 on growth and apoptosis of gastric cancer cell line MKN-45 and SGC-7901 in vitro. Methods MKN-45 and SGC-7901 cells at logarithmic growth phase were obtained, and were cultured with ginsenoside Rg3 of different concentrations (20, 30, 40, 50 μg/mL) for 24, 48 h or 24, 48 and 72 h. Cells cultured without ginsenoside Rg3 were served as controls. The inhibition rates of ginsenoside Rg3 on MKN-45 and SGC-7901 cells were detected by MTT assay, apoptosis rate of SGC-7901 cells was determined by Annexin V/PI double staining flow cytometry, cell cycles of SGC-7901 cells were analysed by flow cytometry, and morphological changes of SGC-7901 cells in 50 μg/mL ginsenoside Rg3 treatment group were observed by transmission electron microscopy. Results The inhibition rates on MKN-45 and SGC-7901 cells in each ginsenoside Rg3 treatment group were significantly higher than those in control group (P < 0.05), and the inhibition rates increased with the concentrations of ginsenoside Rg3 and time of culture ( P < 0.05). Compared with control group, the apoptosis rates of SGC-7901 cells and percentages of cells in G_1/G_1 cell cycle in each ginsenoside Rg3 treatment group were significantly increased in a concentration and time dependent manner. Typical morphology of SGC-7901 cell apoptosis was observed by transmission electron microscopy in 50 μg/mL ginsenoside Rg3 treatment group. Conclusion Ginsenoside Rg3 has significant inhibition effect on gastric cancer cell lines in vitro with a concentration and time dependent manner, the mechanism of which may involve the induction of gastric cell line apoptosis.
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Objective To study the tumorigenetic characteristics of side population (SP) cells and their exsistence in gastric cancer cell lines and tissues.Methods Flow cytometry and the DNA-binding dye Hoechst 33342 staining were used to analyze sorted SP cells in 3 gastric cancer cell lines(SGC-7901,BCIC-823 and MKN28).SP cells and non-SP cells(main population cells)isolated from SGC-7901 cell line weresubcutaneously injected into 36 nude mice with 500,5000 or 50 000 cells per mouse,respectively.Thetumorigenity was observed 8 weeks after injection.The expression of ATP-binding cassette sub-family Gmember 2(ABcG2)mRNA in three gastric cell lines and its level in gastric cancer tissues were detected by real-time PCR and immunostaining.respectively.Results The proportion of SP cells was accounted for 1.0%in SGC-7901 cells and 1.3%in BGc-823 cells.No SP cell was found in MKN28 cells.As low as 500 SP cells or 50 000 non-SP cells could initiate tumors in mice.The expression of ABcG2 mRNA was higher in SGC-7901(O.162)and BGC-823(O.096)cell lines than that in MKN28 cell line(0.005).The value of AtCG2 mRNA/beta-aetin mRNA and protein in gastric cancer tissues was different from those in gastritis tissues.Condasimm SP cells have strong ability of tumorigenesis compared with non-SP cells.The expression of ABCG2 is found in gastric cancer tissues and part gastritis tissues.The more the SP cells in gastric cell lines,the higher the expression of ABCG2.
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PURPOSE: Gastric cancer has the highest incidence rate among cancers in Asia. The advanced type of signet ring cell carcinoma has poor prognosis compared to other types of gastric cancer. The immuno-gene therapy with cytokine-based tumor vaccines has not yet been investigated for gastric cancer. The granulocyte macrophage colony-stimulating factor (GM-CSF)-based tumor vaccine has been demonstrated as the most potent stimulator for specific and long-lasting systemic tumor immunity. MATERIALS AND METHODS: In the present study, KATO III cells, the human signet ring cell gastric carcinoma cell line, were genetically modified by the transduction with the human GM-CSF cDNA or the modified hGM-CSF in replication-deficient retroviruses. The genomic integrations and mRNA expressions of the transgenes were determined by Southern and Northern blot analyses. RESULTS: Wild type (wt) or modified hGM-CSF was integrated into the genome of KATO III cells. The modified hGM-CSF mRNA was more stable than that of wt. The KATO III cells with the modified hGM-CSF produced higher level of hGM-CSF (12.4-19 ng/10(6)cells/48hrs) than that with wt hGM-CSF, when determined by enzyme-linked immunosorbent assay (ELISA). The secreted recombinant hGM-CSF could support the proliferation of the GM-CSF-dependent cell line, indicating that the hGM-CSF secreted by the transduced KATO III cells has biological activities. Irradiated, transduced KATO III cells continued to secret hGM-CSF without proliferation. CONCLUSION: Our results suggest that GM-CSF secreting KATO III cells could be tested for the treatment of gastric cancer as an allogeneic tumor vaccine as a part of immunotherapeutic treatment.
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Humans , Base Sequence , Blotting, Northern , Blotting, Southern , Cell Line, Tumor , Enzyme-Linked Immunosorbent Assay , Mutagenesis , RNA, Messenger/genetics , Recombinant Proteins/metabolism , Stomach Neoplasms/genetics , Transduction, GeneticABSTRACT
PURPOSE: Dopamine is a neurotransmitter, but in the GIT, the roles of dopamine are a regulator of epithelial cell proliferation, an endogenous protective factor, and a regulator of stomach cancer cell proliferation. By using two different gastric-cancer cell lines, we assessed the effects of dopamine and dopamine receptors on the proliferation of human gastric-cancer cells. MATERIALS AND METHODS: To assess the effects of dopamine and dopamine receptors on the proliferation of human gastric-cancer cells, we investigated cell proliferation and the expression of D1, D2L, and D2S receptor in two gastric-cancer cell lines, SNU 601 and KCU-C2. The effects of dopamine and dopamine receptors on the level of the cell proliferation were determined by staining with an A/H/E (acridine orange, hoechst and ethidium bromide) mixture. RESULTS: After dopamine treatment, the cell viability was significantly decreased in SNU 601 cells (P<0.05) where the D2L receptor was absent, but not in KCU-C2 cells. After treatment with raclopride, a D2 receptor antagonist, dopamine-dose-dependent inhibition of cell proliferation was observed in SNU 601 cells (P<0.05). After treatment with SCH 23390, a D1 receptor antagonist, dopamine significantly increased cell proliferation in KCU-C2 cells (P<0.05), but inhibited cell proliferation in SNU 601 cells (no D2L receptor). CONCLUSION: The dopamine signal via the D1 or the D2S receptor inhibited proliferation of gastric-cancer cells, but that via the D2L receptor increased proliferation. These results suggest that the regulatory effects of dopamine in the gastric-cancer cell proliferation may be controlled by using dopamine receptors.
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Humans , Cell Line , Cell Proliferation , Cell Survival , Citrus sinensis , Dopamine , Epithelial Cells , Ethidium , Neurotransmitter Agents , Raclopride , Receptors, Dopamine , Stomach NeoplasmsABSTRACT
0.05), but they did at 48 h(P
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Objective To study whether hTR antisense PS ODN has anticancer effect and the effect of increasing the susceptibility of tumor to DDP, we explore the effect of hTR antisense oligodeoxynucleotide in combination with DDP on human gastric carcinoma transplanted subcutaneously in nude mice in vivo. Methods The model of human gastric carcinoma transplanted subcutaneously was established in thirty nude mice, then divided randomly into 5 groups (Control group, ASODN group, RODN group, DDP group and ASODN+DDP group). The weight of nude mice was measured, and the tumor growth inhibitory rate was calculated. The relative telomerase activity was quantitatively measured by TRAP PCR ELISA methods. Results The maximum tumor inhibitory rate in ASODN+DDP group, ASODN group, DDP group and RODN group was 94.2 %, 84.3 %, 92.8 % and 26.9 % respectively. There was significant difference in the relative telomerase activity among four treatment groups. Conclusions The results suggested that hTR antisense PS ODN may act as a specific tumor growth inhibitor and telomerase activity inhibitor may be in sequence specific manner, and have the effect of increasing the susceptibility of transplanted tumor to DDP.
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PURPOSE: Insulin-like growth factor (IGF)-I and II are potent mitogens, postulated to exert autocrine and paracrine effects on growth regulation in human gastric cancer. In this study, we evaluated the expression of IGF-I, -II and IGFBPs in a panel of human gastric cancer cell lines. We also evaluated whether high expression of IGFBP-3 in human gastric cancer cells may increase the sensitivity to the anti-proliferative agents. MATERIALS AND METHODS: 10 human korean gastric cancer ceIl lines and 1 Caucacian gastric adenocarcinoma cell line were used for this study. IGF and IGFBP expressions were evaluated by RT-PCR. IGFBP proteins in conditioned media were detected by Western Ligand Blot. Cell survival after treatment of anti-proliferative agents was assessed by MTT assay. RESULTS: IGF-I and II were expressed in all gastric cancer cell lines. In addition, IGF-I and II stimulated the proliferation of gastric cancer cells. The expression of IGFBP-2 was found in all gastric cancer cell lines. IGFBP-4 was expressed in the most of cell lines. IGFBP-3, -4 and -6 were expressed in about 50% of cell lines. The growth inhibition of IGFBP-3 expressing cells by anti- proliferative agents was more significant than that of IGFBP-3 nonexpressing cells. Cell growth inhibition with treatment of these agents was accompanied by increased IGFBP-3 mRNA level. CONCLUSION: These data confirm that IGF-I, -II, and certain IGFBPs were expressed in gastric cancer cells, and gastric cancer cells show the differential growth inhibition by anti-proliferative agents. The differential growth inhibitory effect of anti-proliferative agents is, at least in part, mediated through up-regulation of IGFBP-3 expression.
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Humans , Adenocarcinoma , Carrier Proteins , Cell Line , Cell Survival , Culture Media, Conditioned , Insulin-Like Growth Factor Binding Protein 2 , Insulin-Like Growth Factor Binding Protein 3 , Insulin-Like Growth Factor Binding Protein 4 , Insulin-Like Growth Factor Binding Proteins , Insulin-Like Growth Factor I , Mitogens , RNA, Messenger , Stomach Neoplasms , Up-RegulationABSTRACT
We used retrovial vector LXSN to construct recombinant retroviral vector with mutant membrane bound TNF - ? gene. The vectors were introduced into packaging cell line, CRIP cells. The G418-resistant colonies were selected and the supernatants of the colonies were used to determine the virus titers. The titer of virus was 1? 104CFU/ml and the retroviral vectors were used to tranduced the human gastric cancer cell line, MGC-803 cells. The results of southern blot assay showed thai the targel gene had integrated into the genomic DNA of MGC-803T. MGC - 803Tcells were ablc to kill L929 cell line, but the parent cell line showed no cytotoxicily to the cells at all. There was no any variance in the morphological appearance and growlh rate in vilro of MGC-803N and MGC-803T cells. The results of inoculation in nude mice with these cells indicated that MGC-803T cells showed a considerable decrease in size of tumor. These results suggested that the retroviral vectors expressing mulant TNF -? gene were successfully construed. MGC - 803T cells showed cytotoxicily slrongly lo L929 cell line in vilro and lumorigenicity .
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The distribution of receptor sites for concanavalin A (Con A) on the cellsurface of human gastric cancer cell line (MGC 80-3) and fibroblast cell cultures wasstudied with electron and light microscope after application of Con A-peroxidasemethod.The cytochemical reaction of the majority of non-prefixed MGC 80-3 cellsshows a striking tendency to be more uneven distribution than on fibroblasts.Clustering,patching and capping of Con A binding sites on the cancer cells anduniform distribution on the fibroblasts were observed.The effects of incubationtemperature,prefix treatment,different phase of cell cycles and cell growth condi-tions on the distribution of Con A receptor complexes were observed.The possiblereasons for the more irregular distribution of the cytochemical reaction product onthe MGC 80-3 cells than the fibroblasts are discussed.