Objective: To study the effect of somatostatin analogue octreotide on the invasion and metastasis of gastric cancer in vitro and in vivo. Methods: Using membrane invasion culture system alone or coated with matrigel, we observed the effect of octreotide on blocking migration and invasion of gastric carcinoma cells. Nude mice implanted orthotopically with SGC-7901 human stomach carcinoma were given injections of octreotide for 8 weeks. MMP-2 was detected by gelatin zymography or RT-PCR. The microvascular density and VEGF expression were examined by immunohistochemical staining with factor VIII antibody and VEGF antibody. Results: Octreotide significantly inhibit migration(49.8

Objective: To investigate effects of Aspirin on the growth of gastric cancer in vitro and in vivo. Methods: The effects of aspirin on the proliferation of SGC-7901 cells were measured by 3H-thymidine incorporation into DNA and cell cycle analysised by flow cytometric analysis, separately. COX-2 protein was examed in SGC-7901 cells by immunohistochemistry. The expression of c-Fos and AP-1 activity were detected by immunoblotting and EMSA separately. Results: Aspirin significantly decreased 3H-thymidine incorporation into SGC-7901 cells. Among concentration of 1

Objective: To investigate the effects of somatostatin analogue octreotide on the proliferation and apoptosis of human hepatocellular carcinoma (HCC) cell line as well as the growth of HCC xenografts in nude mice. Methods The effects of octreotide on the proliferation and apoptosis of SMMC-7721 HCC cells was measured by 3H-thymidine incorporation into DNA and the TdT-mediated dUTP nick end labeling assay (TUNEL) or flow cytometric assay separately. Nude mice bearing xenografts of the cell line were treated with octreotide or saline as a control daily until eight weeks after tumor implantation. Results Incubation with octreotide decreased 3H-thymidine incorporation into DNA of SMMC-7721 cells by～50% at a concentration of 1μM. The inhibit effect of octreotide showed a concentration dependence. After 96h incubation, total cell count was decreased 52.2% compared with control. When cells were treated by octreotide at 1×10-6mol/L for 24 hours, the apoptosis rates was (15.2±2.4)%. At necropsy, in mice given octreotide, the mean tumor weight were significantly lower than that of control group(0.27±0.05 vs 0.85±0.37,P<0.01). The inhibition rate of tumor in vivo at 2 months was 68.2%. Conclusion Octreotide is effective in inhibiting growth of HCC both in vivo and in vitro significantly. The mechanisms of antineoplastic effect action may involved in inhibiting DNA synthesize and inducing apoptosis of tumor cells.

To observe the effect of vasoactive intestinal peptide(VIP) or somatostatin (SST) on the lymphocytes traffic in gut-associated lymphoid tissues in rat, 18 rats were divided into three groups at random. VIP and SST were continuously infused from femoral vein at a dose of 60 pmol/h for 7 h. It was found that the lymphocytes in intestinal lymph collected in 5 hours were significantly reduced after VIP and SST administration(P<0.05). Although the volume decreasing of intestinal lymph was happened in all groups, no significant changes in lymph flow were observed in control and treat groups. The percentages of CD8+ cells in intestinal lymph of rat treated by VIP or SST was markedly lower than that in control group (P<0.05). Finally, either VIP or SST infusion reduced CD8+ cells in the small intestinal mucosa when compared with control. It concludes that either VIP or SST not only reduces lymphocytes, especially CD8+ cells traffic from intestinal mucosa immune system to other organs and systemic immune system but also suppresses the homing of CD8+lymphocytes into intestinal mucosa immune system in rats.

Objective: To observe the effect of VIP or SST on the lymphocyte homing to the intestinal tract. Methods: Intestinal lymph were collected from mesenteric lymphatic duct of rats. Intestinal lymphocytes, which had been incubated with VIP or SST, were labeled with 51Cr and then were infused into blood circulation of rats. The 51Cr-intestinal lymphocytes in organs (or tissues)were determined with γ-counter. Results: About 10% of 51Cr-intestinal lymphocytes homed to intestinal tract within 1 h at normal physiological state. The distribution of 51Cr-intestinal lymphocytes treated with either VIP or SST in mesenteric node (1.83% or1.56%) and in Peyer's patches (1.85% or 1.60%) were significantly lower than that of control group (3.83%, 3.85%), P<0.05. VIP or SST did not show remarkable affection on the homing of 51Cr-intestinal lymphocytes to diffusive lymphatic tissue in small intestine when compared with control. Conclusion: Either VIP or SST reduces the homing of intestinal lymphocytes to mesenteric nodes and Peyer's patches in rats.