AIM: Somatostatin and its analogues may suppress the growth of various tumor cells. However, the effect of octreotide on growth of gastric adenocarcinoma is still largely unknown. This study was to explore if octreoti...AIM: Somatostatin and its analogues may suppress the growth of various tumor cells. However, the effect of octreotide on growth of gastric adenocarcinoma is still largely unknown. This study was to explore if octreotide could inhibit the growth of gastric adenocarcinoma and its probable mechanisms.METHODS: Proliferation of gastric cancer cell line affected by octreotide was determined by 3H-thymidine incorporation.After xenografts of human gastric cancer were implanted orthotopically in stomach, nude mice were administrated octreotide for 8 weeks. The mRNA of somatostatin receptor in the SGC-7901 cells was detected by reverse transcription polymerase chain reaction technique. Extracellular signalregulated protein kinase and c-Fos in gastric cancer tissues were measured by immunohistochemistry and Western blot.Activator protein-1 binding activity was examined by electrophoretic mobility sift assay.RESULTS: 3H-thymidine incorporation into SGC-7901 cells was significantly decreased by octreotide in a concentration dependent manner. Either size or weight of tumors treated with octreotide was significantly reduced in vivo. The inhibition rate for tumor was 62.3% in octreotide group.The genes of somatostatin receptors 2 and 3 were expressed in SGC-7901 gastric cancer cell lines. Extracellular signal-regulated protein kinase and c-Fos protein level were decreased in gastric adenocarcinoma treated with octreotide. Moreover, fetal calf serum stimulated activator protein-1 binding activity could be suppressed by octreotide potentially.CONCLUSION: Inhibition of sequential molecular events in MAPK pathway may interpret the mechanisms underlying the effect of octreotide on the growth of gastric adenocarcinoma.展开更多
AIM:To study the effect of probiotics on interleukin-8 secretion in intestinal epithelia when stimulated by proinflammatory cytokines.METHODS: Colonic adenocarcinoma HT29 cells were cultured and divided into four grou...AIM:To study the effect of probiotics on interleukin-8 secretion in intestinal epithelia when stimulated by proinflammatory cytokines.METHODS: Colonic adenocarcinoma HT29 cells were cultured and divided into four groups:control,TNF-α (group T in short),bifidobacterium (group B), lactobacillus (group L). B. Longum and L. bulgaricus were suspended in culture medium with a concentration of 1×10^8cfu/ml and added into 24 wells respectively. One hour later TNF-α (10ng/ml) was added into each well of groups T, B, L. The supernatants were collected and measured for IL-8 after 3 hours, nuclear factor-κB (NF-κB) p65 was also examined by Western blotting.RESULTS:There was less interleukin-8 secretion in HT29 cells when preincubated with B. Longum or L. bulgaricus compared with group T.Less p65 appeared in nuclei in groups B and L compared with group T,as detected by Westem blot.CONCLUSION:Probiotics can suppress interleukin-8 secretion in intestinal epithelia when stimulated by proinflammatory cytokines, which is most likely mediated by NF-κB.展开更多
基金the National Natural Science Foundation of China for Excellent Young Scientists,No.39725012the National Natural Science Foundation of China,No.30170418
文摘AIM: Somatostatin and its analogues may suppress the growth of various tumor cells. However, the effect of octreotide on growth of gastric adenocarcinoma is still largely unknown. This study was to explore if octreotide could inhibit the growth of gastric adenocarcinoma and its probable mechanisms.METHODS: Proliferation of gastric cancer cell line affected by octreotide was determined by 3H-thymidine incorporation.After xenografts of human gastric cancer were implanted orthotopically in stomach, nude mice were administrated octreotide for 8 weeks. The mRNA of somatostatin receptor in the SGC-7901 cells was detected by reverse transcription polymerase chain reaction technique. Extracellular signalregulated protein kinase and c-Fos in gastric cancer tissues were measured by immunohistochemistry and Western blot.Activator protein-1 binding activity was examined by electrophoretic mobility sift assay.RESULTS: 3H-thymidine incorporation into SGC-7901 cells was significantly decreased by octreotide in a concentration dependent manner. Either size or weight of tumors treated with octreotide was significantly reduced in vivo. The inhibition rate for tumor was 62.3% in octreotide group.The genes of somatostatin receptors 2 and 3 were expressed in SGC-7901 gastric cancer cell lines. Extracellular signal-regulated protein kinase and c-Fos protein level were decreased in gastric adenocarcinoma treated with octreotide. Moreover, fetal calf serum stimulated activator protein-1 binding activity could be suppressed by octreotide potentially.CONCLUSION: Inhibition of sequential molecular events in MAPK pathway may interpret the mechanisms underlying the effect of octreotide on the growth of gastric adenocarcinoma.
文摘AIM:To study the effect of probiotics on interleukin-8 secretion in intestinal epithelia when stimulated by proinflammatory cytokines.METHODS: Colonic adenocarcinoma HT29 cells were cultured and divided into four groups:control,TNF-α (group T in short),bifidobacterium (group B), lactobacillus (group L). B. Longum and L. bulgaricus were suspended in culture medium with a concentration of 1×10^8cfu/ml and added into 24 wells respectively. One hour later TNF-α (10ng/ml) was added into each well of groups T, B, L. The supernatants were collected and measured for IL-8 after 3 hours, nuclear factor-κB (NF-κB) p65 was also examined by Western blotting.RESULTS:There was less interleukin-8 secretion in HT29 cells when preincubated with B. Longum or L. bulgaricus compared with group T.Less p65 appeared in nuclei in groups B and L compared with group T,as detected by Westem blot.CONCLUSION:Probiotics can suppress interleukin-8 secretion in intestinal epithelia when stimulated by proinflammatory cytokines, which is most likely mediated by NF-κB.
