上调Decorin对口腔鳞癌荷瘤裸鼠EGFR、C-Myc、p21表达的影响

Effect of up-regulation of Decorin on expression of EGFR, C-Myc and p21 in nude mice with oral squamous cell carcinoma

目的:探讨饰胶蛋白聚糖基因(decorin,DCN)过表达对口腔鳞癌(oral squamous cell carcinoma,OSCC)裸鼠荷瘤中表皮生长因子受体(epidermal growth factor receptor,EGFR)、骨髓细胞瘤病毒癌基因(cellular-myelocytomatosis viral oncogene,C-Myc)和细胞周期蛋白依赖性激酶抑制剂(cyclin dependent kinase inhibitor,p21)表达水平的影响。方法:通过脂质体转染法上调人口腔鳞癌细胞(HSC-3)中DCN基因的表达,使用裸鼠作为OSCC疾病模型构建载体,建立OSCC裸鼠荷瘤模型。H-E法确定各组裸鼠荷瘤组织的病理分级,免疫组织化学染色检测DCN过表达后各组裸鼠荷瘤组织中EGFR、C-Myc和p21蛋白的表达差异,RT-qPCR及Western印迹定量检测DCN过表达后各组裸鼠荷瘤组织中EGFR、C-Myc和p21在转录水平和蛋白水平上的表达差异,明确DCN过表达对OSCC裸鼠荷瘤组织中EGFR、C-Myc和p21表达的影响。采用SPSS 20.0软件包对数据进行统计学分析。结果:H-E染色结果显示,OSCC动物疾病模型构建成功。重量分析结果显示,质粒组裸鼠荷瘤组织轻于空载组和未转染组(P<0.05)。IHC结果显示,DCN、EGFR、C-Myc和p21蛋白在各组裸鼠荷瘤组织中均有表达,质粒组中DCN、EGFR和C-Myc蛋白的表达水平差异有统计学意义(P<0.05),各组中p21蛋白的表达水平无统计学差异(P>0.05)。RT-qPCR和Western印迹结果显示,DCN、EGFR、C-Myc和p21在各组裸鼠荷瘤组织中均有不同程度表达(P<0.05)。结论:上调DCN可抑制OSCC裸鼠荷瘤的生长。在OSCC裸鼠荷瘤组织中,DCN过表达下调EGFR及C-Myc的表达,上调p21的表达。DCN可能通过以上机制调节OSCC的发生、发展,发挥抑癌作用。

PURPOSE: To explore the effect of overexpression of DCN(decorin) gene on the expression of epidermal growth factor receptor(EGFR), cellular-myelocytomatosis viral oncogene(C-Myc) and cyclin dependent kinase inhibitor(p21)in tumor-bearing nude mice with oral squamous cell carcinoma(OSCC). METHODS: The expression of DCN gene in human oral squamous cell carcinoma(HSC-3) was up-regulated by liposome transfection. Nude mice were used as the carrier of OSCC. H-E staining was used to determine the pathological grade of tumor-bearing tissues in each group. Im-munohistochemistry was used to detect the expression of EGFR, C-Myc and p21 protein in tumor-bearing tissues of each group after DCN overexpression. RT-qPCR and Western blot were used to quantitatively detect the expression of EGFR,C-Myc and p21 in tumor-bearing tissues of each group after DCN overexpression, and to determine the effects of DCN overexpression on the expression of EGFR, C-Myc and p21 in tumor-bearing tissues of OSCC nude mice. SPSS 20.0 software package was used for statistical analysis. RESULTS: H-E staining showed that the animal model of OSCC was successfully constructed. The tumor-bearing tissues of nude mice in the plasmid group were significantly lighter than those in the empty vector group and non-transfected group(P<0.05). IHC results showed that DCN, EGFR, C-Myc and p21 proteins were expressed in the tumor-bearing tissues of nude mice in each group, the expression of DCN,EGFR and C-Myc proteins in the plasmid group was significantly different from the other groups(P<0.05).There was no significant differece in p21 protein expression in each group(P>0.05). RT-qPCR and Western blot results showed that DCN, EGFR, C-Myc and p21 were expressed in diffrent degrees in tumor-bearing tissues of nude mice(P<0.05). CONCLUSIONS: DCN can inhibit the growth of tumor in OSCC nude mice. In tumor-bearing tissues of nude mice with OSCC, overexpression of DCN can down-regulate the expression of EGFR and C-Myc, and up-regulate the expression of p21.DCN may play an inhibitory role in the occurrence and development of OSCC.