中文摘要：

[目的]研究维甲酸（RA）对裸鼠原位荷人胃癌细胞BGC-803移植瘤和肝转移的抑制作用。[方法]建立人胃癌裸鼠原位种植肝转移模型，分为2组，对照组和RA组，种植后第5天开始，分别自腹腔注射0．85％氯化钠、RA（1mg／kg），每日1次，第8周处死动物，检测抑瘤率、胃癌细胞凋亡指数（AD，观察肿瘤细胞肝转移以及金属基质蛋白酶2（MMP-2）、增殖细胞核抗原（PCNA）的表达情况。[结果]RA组的抑瘤率为37．8％。与对照组相比，RA组胃癌生长、肝转移受到明显抑制（P〈0．05），AI明显增高（P〈0．05），MMP-2、PCNA的表达降低。[结论]RA对胃癌生长和肝转移的抑制可能通过诱导胃癌细胞凋亡、抑制细胞增殖以及肿瘤细胞外基质降解实现的。

英文摘要：

[Objective]To study the experimental therapeutic effects of retinoic acid （RA）on metastasis to the liver of implanted human gastric cancer cell BGC-803 in nude mice. [Methods] The human gastric cancer cell BGC-803 grown lump were transplanted into the gastric of nude mice to set up a model for better investigation of the liver metastasis of gastric cancer. Mice were randomly divided into 2 groups.control group（saline solution）, RA group（RA 1 mg. kg^-1. d^-1 i.p）, beginning from the 5th day post-implantation. Eight weeks after implantation, the inhibition rates, apoptotic index（AI）, and the presence the metastases were evaluated respectively. Then the above tissue samples were fixed and embedded in paraffin, and then deparaffinized HE staining and immunohistochemical staining for MMP-2, PCNA was performed. [Results]The inhibition rate of tumor were 37. 8% in RA group. The growth and liver metastasis of human gastric cancer cell BGC-803 implanted in nude mice were exhibited the stronger inhibitory effect in RA group than in control group（P〈0. 05）. The AI was significantly increased in RA group than in control group（P〈0. 05）. Expression of MMP-2 and PCNA were decreased in the liver metastasis tissues of gastric cancer in nude mice after RA treatment. [Conelusion]The treatment of RA on nude mice bearing gastric cancer can effectively inhibit tumor growth and metastasis by inducing tumor cell apoptosis and inhibiting cell proliferation and extracellular matrix degradation.