Effect of intestinal lymphatic circulation blockage in two-hit rats

AIM: To study the effect of blocking intestinal lymphatic circulation in two-hit rats and explore the significance of intestinal lymphatic circulation in two-hit. METHODS: Wistar rats were divided equally into three groups: mesenteric lymph duct ligation group, non- ligation group and sham group. Mesenteric lymph was diverted by ligation of mesenteric lymph duct, and the two-hit model was established by hemorrhage and lipopolysaccharide (LPS) methods. All rats were sampled for serum pre-experiment and 24 h post- experiment. The organs including kidney, liver, lung and heart were collected for pathomorphologic observation and biochemical investigation. The nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) were determined in serum and tissue homogenate. RESULTS: Pathomorphology study showed that the structures of kidney, lung, liver and heart tissues were normal in sham group; congestion, degeneration and necrosis in non-ligation group; but only mild lesions in ligation group. After two-hits, the contents of AST, ALT, BUN, Cr and LDH-1 in the serum of non-ligation group and ligation group were obviously higher than that in pre-experiment group and sham group, but obviously lower than that in non-ligation group. The contents of NO2-/NO3-, NOS, iNOS and MDA in the serum of non- ligation group were significantly increased, compared with pre-experiment and sham group, but SOD was significantly lower. These parameters were significantly different in ligation group compared with that in sham group, but NO2-/NO3-, iNOS and MDA in ligation group were significantly lower than that in non-ligation group. CONCLUSION: Ligation of mesenteric lymph duct could improve the disturbance of organic function and morphologic damage in two-hit rats; the lymphatic mechanism in two-hit should be emphasized.

Correlation of integrin β3 mRNA and vascular endothelial growth factor protein expression profiles with the clinicopathological features and prognosis of gastric carcinoma

AIM:To investigate integrin β3 mRNA and vascular endothelial growth factor (VEGF) protein expression in gastric carcinoma, and its correlation with microvascular density, growth-pattern, invasion, metastasis and prognosis. METHODS: In situ hybridization (ISH) of integrin β3 mRNA and immunohistochemistry of VEGF and CD34 protein were performed on samples from 118 patients with gastric cancer. RESULTS: The positive rate of integrin β3 mRNA in non- tumor gastric mucosa (20%) was significantly lower than that of the gastric cancer tissue (52.5%, χ2 = 10.20, P < 0.01). In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of integrin β3 mRNA were significantly higher than those in patients of expanding type (P < 0.01), stage T1-T2 (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of VEGF protein were significantly higher than those in patients of expanding type (P < 0.01), stage T1-T2 (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic orperitoneal metastasis, the mean MVD were significantly higher than those in patients of expanding type (P < 0.01), stage T1-T2 (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. It was found that the positive expression rate of integrin β3 mRNA was positively related to that of VEGF protein (P < 0.01) and MVD (P < 0.05), meanwhile the positive expression rate of VEGF protein was positively related to MVD (P < 0.05). The mean survival period in patients with positive expression of integrin β3 mRNA and VEGF, and MVD ≥ 54.9/mm2 was significantly shorter than that in patients with negative expression of integrin β3 mRNA (P < 0.05) and VEGF (P < 0.01), and MVD < 54.9/mm2 (P < 0.01). Five-year survival rate in patients with positive expression of integrin β3 mRNA and VEGF, and MVD ≥ 54.9/mm2 was significantly lower than those with negative expression of integrin β3 mRNA (P < 0.05), VEGF (P < 0.05), and MVD < 54.9/mm2 (P < 0.01). CONCLUSION: Integrin β3 and VEGF expression can synergistically enhance tumor angiogenesis, and may play a crucial role in invasion and metastasis of gastric carcinoma. Therefore, they may be prognostic biomarkers and novel molecular therapeutic targets.