AIM: To explore the inhibition of conjugated linoleic acidisomers in different purity (75 % purity c9,t11-, 98 % purityc9,t11- and 98 % purity t10,c12-CLA) on the formation offorestomach neoplasm and cheopreventive me...AIM: To explore the inhibition of conjugated linoleic acidisomers in different purity (75 % purity c9,t11-, 98 % purityc9,t11- and 98 % purity t10,c12-CLA) on the formation offorestomach neoplasm and cheopreventive mechanisms.METHODS: Forestomach neoplasm model induced by B(a)P in KunMing mice was established. The numbers of tumorand diameter of each tumor in forestomach were counted;the mice plasma malondialdehyde (MDA) were measuredby TBARS assay; TUNEL assay was used to analyze theapoptosis in forestomach neoplasia and the expression ofMEK-1, ERK-1, MKP-1 protein in forestomach neoplasm werestudied by Western Blotting assay.RESULTS: The incidence of neoplasm in B(a)P group, 75 %purity c9, t11-CLA group, 98 % purity cg,t11-CLA groupand 98 % purity t10, c12-CLA group was 100 %, 75.0 %(P＞0.05), 69.2 % (P＜0.05) and 53.8 % (P＜0.05) respectivelyand the effect of two CLA isomers in 98 % purity onforestomach neoplasia was significant; CLA showed noinfluence on the average tumor numbers in tumor-bearingmouse, but significantly decreased the tumor size, the tumoraverage diameter of mice in 75 % purity c9,t11-CLA group,98 % purity cg,t11-CLA group and 98 % purity t10, c12-CLAgroup was 0.157±0.047 cm, 0.127±0.038 cm and 0.128±0.077 cm (P＜0.05) and 0.216±0.088 cm in B(a)P group;CLA could also significantly increase the apoptosis cellnumbers by 144.00±20.31, 153.75±23.25, 157.25±15.95(P＜0.05) in 75 % purity c9,t11-CLA group, 98 % purity c9,t11-CLA group and 98 % purity t10,c12-CLA group (30.88±3.72 in BP group); but there were no significant differencesbetween the effects of 75 % purity c9,t11-CLA and twoisomers in 98 % purity on tumor size and apoptotic cellnumbers; the plasma levels of MDA in were increased by75 % purity c9,t11-ClA, 98 % purity c9,t11-CLA and 98 %purity t10,c12-CLA. The 75 % purity c9,t11-CLA showedstronger inhibition; CLA could also inhibit the expression ofERK-1 protein and promote the expression of MKP-1 protein,however no influence of CLA on MEK-1 protein was observed.CONCLUSION: Two isomers in 98 % purity show strongerinhibition on carcinogenesis. However, the inhibitorymechanisms of CLA on carcinogenesis is complicated, whichmay be due to the increased mice plasmaMDA, the inducingapoptosis in tumor tissues. And the effect of CLA on theexpression of ERK-1 and MKP-1 may be one of themechanisms of the inhibition of CLA on the tumor.展开更多
AIM: To investigate the effect of c9, t1l-conjugated linoleic acid (c9, t11-CLA) on the invasion of human gastric carcinoma cell line and its possible mechanism of preventing metastasis.METHODS: Using reconstituted ba...AIM: To investigate the effect of c9, t1l-conjugated linoleic acid (c9, t11-CLA) on the invasion of human gastric carcinoma cell line and its possible mechanism of preventing metastasis.METHODS: Using reconstituted basement membrane invasion, chemotaxis, adhesion, PAGE substrate zymography and RT-PCR assays, we analyzed the abilities of invasion,direct migration, adhesion of intracellular matrix, as well as the activity of type IV collagenase and expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 mRNA in SGC-7901 cells which were treated with gradually increased concentrations (25, 50, 100 and 200μmol/L) of c9,c11-CLA for 24 h.RESULTS: At the concentrations of 200μmol/L, 100μmol/L and 50μmol/L, c9,tll-CLA suppressed the invasion of SGC-7901 cells into the reconstituted basement membrane by 53.7 %, 40.9 % and 29.3 %, respectively, in comparison with the negative control. Only in the 200 μmol/L c9,tll-CLA group, the chemotaxis of SGC-7901 cells was inhibited by 16.0 % in comparision with the negative control. C9,tll-CLA also could inhibit the adhesion of SGC-7901 cells to laminin, fibronectin and Matrigel, increase the expression of TIMP-1 and TIMP-2 mRNA, and reduce type IV collegenase activities in the serum-free medium supernatant of SGC-7901 cells.CONCLUSION: c9,t11-C:LA can inhibit the invasion of SGC-7901 cells at multiple procedures in tumor metastasis cascade, which may be associated with the induction of TIMP-1 and TIMP-2 mRNA expression.展开更多
AIM: To investigate the effect of c9, t11-conjugated linoleic acid (c9,t11-CLA) on the adhesion of human gastric carcinoma cell line (SGC-7901).METHODS: SGC-7901 cells were at first treated with different concentratio...AIM: To investigate the effect of c9, t11-conjugated linoleic acid (c9,t11-CLA) on the adhesion of human gastric carcinoma cell line (SGC-7901).METHODS: SGC-7901 cells were at first treated with different concentrations (25, 50, 100, 200 μmol/L) of c9,t111-CLA and 1 mL/L ethanol (as a negative control) for 24 h.Using adhesion assay and Western blot, we investigated the ability of SGC-7901 cells to adhere to intracellular matrix and examined the expression of E-cadherin (ECD), α-catenin,intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in these cells.RESULTS: The attachment rate to laminin of SGC-7901 cells treated with different concentrations of c9,t11-CLA (0,25, 50, 100, and 200 μmol/L) was 100.0±3.3, 95.7±4.0,89.2±4.6, 87.9±6.1, and 65.9±5.8, respectively. The attachment rate to fibronectin was 100.0±4.7, 96.8±3.8,94.5±4.1, 76.5±4.3, and 61.8±4.8, respectively. The attachment rate to Matrigel was 99.9±6.6, 91.4±6.8,85.5±7.4, 79.3±5.6, and 69.6±5.1, respectively. Besides,c9,t11-CLA could increase the level of ECD and α-catenin,and decrease the level of ICAM-1 and VCAM-1 in SGC-7901 cells.CONCLUSION: c9, t11-CLA can reduce the adhesion of human gastric carcinoma cells to laminin, fibronectin and Matrigel. c9,t11-CLA can increase the level of ECD and α-catenin, and decrease the level of ICAM-1 and VCAM-1 in human gastric carcinoma cells.展开更多
基金the National Natural Science Foundation ot China, No.30070658
文摘AIM: To explore the inhibition of conjugated linoleic acidisomers in different purity (75 % purity c9,t11-, 98 % purityc9,t11- and 98 % purity t10,c12-CLA) on the formation offorestomach neoplasm and cheopreventive mechanisms.METHODS: Forestomach neoplasm model induced by B(a)P in KunMing mice was established. The numbers of tumorand diameter of each tumor in forestomach were counted;the mice plasma malondialdehyde (MDA) were measuredby TBARS assay; TUNEL assay was used to analyze theapoptosis in forestomach neoplasia and the expression ofMEK-1, ERK-1, MKP-1 protein in forestomach neoplasm werestudied by Western Blotting assay.RESULTS: The incidence of neoplasm in B(a)P group, 75 %purity c9, t11-CLA group, 98 % purity cg,t11-CLA groupand 98 % purity t10, c12-CLA group was 100 %, 75.0 %(P＞0.05), 69.2 % (P＜0.05) and 53.8 % (P＜0.05) respectivelyand the effect of two CLA isomers in 98 % purity onforestomach neoplasia was significant; CLA showed noinfluence on the average tumor numbers in tumor-bearingmouse, but significantly decreased the tumor size, the tumoraverage diameter of mice in 75 % purity c9,t11-CLA group,98 % purity cg,t11-CLA group and 98 % purity t10, c12-CLAgroup was 0.157±0.047 cm, 0.127±0.038 cm and 0.128±0.077 cm (P＜0.05) and 0.216±0.088 cm in B(a)P group;CLA could also significantly increase the apoptosis cellnumbers by 144.00±20.31, 153.75±23.25, 157.25±15.95(P＜0.05) in 75 % purity c9,t11-CLA group, 98 % purity c9,t11-CLA group and 98 % purity t10,c12-CLA group (30.88±3.72 in BP group); but there were no significant differencesbetween the effects of 75 % purity c9,t11-CLA and twoisomers in 98 % purity on tumor size and apoptotic cellnumbers; the plasma levels of MDA in were increased by75 % purity c9,t11-ClA, 98 % purity c9,t11-CLA and 98 %purity t10,c12-CLA. The 75 % purity c9,t11-CLA showedstronger inhibition; CLA could also inhibit the expression ofERK-1 protein and promote the expression of MKP-1 protein,however no influence of CLA on MEK-1 protein was observed.CONCLUSION: Two isomers in 98 % purity show strongerinhibition on carcinogenesis. However, the inhibitorymechanisms of CLA on carcinogenesis is complicated, whichmay be due to the increased mice plasmaMDA, the inducingapoptosis in tumor tissues. And the effect of CLA on theexpression of ERK-1 and MKP-1 may be one of themechanisms of the inhibition of CLA on the tumor.
基金the National Natural Science Foundation of China, No.30070658
文摘AIM: To investigate the effect of c9, t1l-conjugated linoleic acid (c9, t11-CLA) on the invasion of human gastric carcinoma cell line and its possible mechanism of preventing metastasis.METHODS: Using reconstituted basement membrane invasion, chemotaxis, adhesion, PAGE substrate zymography and RT-PCR assays, we analyzed the abilities of invasion,direct migration, adhesion of intracellular matrix, as well as the activity of type IV collagenase and expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 mRNA in SGC-7901 cells which were treated with gradually increased concentrations (25, 50, 100 and 200μmol/L) of c9,c11-CLA for 24 h.RESULTS: At the concentrations of 200μmol/L, 100μmol/L and 50μmol/L, c9,tll-CLA suppressed the invasion of SGC-7901 cells into the reconstituted basement membrane by 53.7 %, 40.9 % and 29.3 %, respectively, in comparison with the negative control. Only in the 200 μmol/L c9,tll-CLA group, the chemotaxis of SGC-7901 cells was inhibited by 16.0 % in comparision with the negative control. C9,tll-CLA also could inhibit the adhesion of SGC-7901 cells to laminin, fibronectin and Matrigel, increase the expression of TIMP-1 and TIMP-2 mRNA, and reduce type IV collegenase activities in the serum-free medium supernatant of SGC-7901 cells.CONCLUSION: c9,t11-C:LA can inhibit the invasion of SGC-7901 cells at multiple procedures in tumor metastasis cascade, which may be associated with the induction of TIMP-1 and TIMP-2 mRNA expression.
基金Supported by the National Natural Science Foundation of China,No.30070658
文摘AIM: To investigate the effect of c9, t11-conjugated linoleic acid (c9,t11-CLA) on the adhesion of human gastric carcinoma cell line (SGC-7901).METHODS: SGC-7901 cells were at first treated with different concentrations (25, 50, 100, 200 μmol/L) of c9,t111-CLA and 1 mL/L ethanol (as a negative control) for 24 h.Using adhesion assay and Western blot, we investigated the ability of SGC-7901 cells to adhere to intracellular matrix and examined the expression of E-cadherin (ECD), α-catenin,intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in these cells.RESULTS: The attachment rate to laminin of SGC-7901 cells treated with different concentrations of c9,t11-CLA (0,25, 50, 100, and 200 μmol/L) was 100.0±3.3, 95.7±4.0,89.2±4.6, 87.9±6.1, and 65.9±5.8, respectively. The attachment rate to fibronectin was 100.0±4.7, 96.8±3.8,94.5±4.1, 76.5±4.3, and 61.8±4.8, respectively. The attachment rate to Matrigel was 99.9±6.6, 91.4±6.8,85.5±7.4, 79.3±5.6, and 69.6±5.1, respectively. Besides,c9,t11-CLA could increase the level of ECD and α-catenin,and decrease the level of ICAM-1 and VCAM-1 in SGC-7901 cells.CONCLUSION: c9, t11-CLA can reduce the adhesion of human gastric carcinoma cells to laminin, fibronectin and Matrigel. c9,t11-CLA can increase the level of ECD and α-catenin, and decrease the level of ICAM-1 and VCAM-1 in human gastric carcinoma cells.
