[Inhibition of human gastric cancer metastasis by ocreotide in vitro and in vivo].
OBJECTIVE
To study the effect of somatostatin analogue octreotide on the invasion and metastasis of gastric cancer in vitro and in vivo.


METHODS
A nude mouse model of transplanted in situ human gastric cancer was established by implanting SGC-7901 human gastric cancer cells under the skin of nude rats. Twelve experimental animals were divided into two groups, 6 in each group: octreotide group and control group subcutaneously injected with octreotide of the dose of 100 microgram /g(-1) / (-1) and normal saline of the same dose respectively for 8 weeks. By the end of the 8(th) week, the animals were killed and the tumors were taken out to be examined pathologically. Metastasis was observed too. Microvascular density and VEGF expression were examined by immunohistochemistry with factor VIII and VEGF antibody. The expression of MMP-2 gene in gastric cancer cell was examined by gelatin zymography and RT-PCR. The upper chamber cavity walls of membrane invasion culture system were covered with matrigel and SGC-7901 cells and octreotide were added into the chambers. After 12 hours' culture, the migration and invasion of cancer cells were observed.


RESULTS
In the membrane invasion culture system, the numbers of invading and migrating SGC-7901 cells were significantly lower in octreotide group than in the control group. Metastasis was seen in 4 of the 6 control mice and was seen in only one of the 6 octreotide treated mice. The microvascular density was lower in octreotide treated mice than in the control. The VEGF and MMP-2 expression was inhibited by octreotide.


CONCLUSIONS
Octreotide inhibits the migration and invasion of SGC-7901 gastric cancer cells in vitro and inhibits the metastasis of cancer in vivo. Tha mechanism may be down-regulation of MMP-2 expression and decrease of tumor angiogenesis.
Wang
Chunhei
C
Department of Gastroenterology, First Hospital, Chongqing University of Medical Sciences, Chongqing 400016, China.
Tang
Chengwei
C
D000818:Animals; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D002465:Cell Movement / Q000187:drug effects; D004195:Disease Models, Animal; D016228:Endothelial Growth Factors / Q000378:metabolism; D006801:Humans; D008222:Lymphokines / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D015282:Octreotide / Q000627:therapeutic use*; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D023041:Xenograft Model Antitumor Assays
D018931:Antineoplastic Agents, Hormonal; D016228:Endothelial Growth Factors; D008222:Lymphokines; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D020778:Matrix Metalloproteinase 2; D015282:Octreotide