生存素的表达与胃癌细胞凋亡和生物学行为的关系

Expression of survivin and its Relationship with Apoptosis and Biological Behaviors of Gastric Cancer

背景:生存素是新近发现的凋亡蛋白抑制因子家族成员之一,其再表达于大多数人类肿瘤组织中,可能成为恶性肿瘤诊断和治疗的新靶点。目的:探讨生存素的表达与胃癌细胞凋亡和生物学行为的关系。方法:分别以逆转录聚合酶链反应(RT-PCR)和免疫组化方法检测胃癌和癌旁组织中生存素mRNA和蛋白的表达;以原位末端标记(TUNEL)法检测胃癌细胞凋亡。结果:生存素mRNA和蛋白在胃癌组织中高表达,在癌旁组织中不表达。其表达与肿瘤大小、部位、浸润深度和淋巴结转移无明显相关性,但与肿瘤分化程度相关。所有胃癌组织中均能检测到凋亡细胞,但生存素蛋白表达阳性者的凋亡指数(AI)显著低于表达阴性者(2.5%±2.2%对5.2%±2.7%,P<0.05)。结论:生存素在胃癌组织中表达上调,其表达与胃癌分化程度相关,并可抑制胃癌细胞凋亡,可作为评价胃癌分化程度和估计预后的参考指标。

Background： Survivin, the new member of inhibitors of apoptosis protein, is re-expressed in almost all human cancer tissues and may be a novel target for the diagnosis and treatment of cancers. Aims： To investigate the expression of survivin and its relationship with apoptosis and biological behaviors of gastric cancer. Methods： Reverse transcriptase polymerase chain reaction （RT-PCR） was used to assess the expression of survivin mRNA in gastric cancer and paracancerous tissues, and survivin protein expression was detected by immunohistochemical assay. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling （TUNEL） was employed to examine the apoptosis of gastric cancer cells. Results： Survivin mRNA and its protein were highly expressed in gastric cancer tissues. In contrast, no expression of survivin was detected in paracancerous tissues. The expression of survivin was not related to the size, sites, infiltration and lymph node metastasis of gastric cancer, but was correlated with the degree of tumor differentiation. Apoptosis was observed in all cancer tissues, but apoptotic index （AI） in survivin protein-positive tissues was significantly lower than that in survivin proteinnegative tissues （2.5%±2.2% vs. 5.2%±2.7%, P〈0.05）. Conclusions： The expression of survivin in gastric cancer tissues is up-regulated. Its expression is associated with the degree of tumor differentiation, and can inhibit the apoptosis of gastric cancer cells. Survivin might be a referenced indicator in evaluating the differentiation and predicting the prognosis of gastric cancer.