5’-脱氧氟尿苷联合干扰素对转染TP基因结肠癌细胞株裸鼠实验模型的影响  

The anti-tumor effects of 5'-DFUR combined with interferon on nude mice transplanted with colorectal cancer cell line LS174T carrying thymidine phosphorylase cDNA

作　　者：方耿[1] 王绮雯[1] 张继民[1] 

机构地区：[1]广州医科大学附属第二医院胃肠外科,广东广州510260

出　　处：《中国癌症杂志》2017年第11期853-859,共7页China Oncology

基　　金：国家自然科学基金(81071883)

摘　　要：背景与目的:人结直肠癌细胞基本无胸苷磷酸化酶(thymidine phosphorylase,TP)表达。本实验主要探讨人结肠癌细胞株LS174T转染TP基因后,在裸鼠肿瘤组织中对抗癌药物5’-脱氧氟尿苷(5’-deoxy-5-fluorouridine,5’-DFUR)、氟尿嘧啶(5-fluorouracil,5-FU)和干扰素-α2a(interferon-α2a,INF-α2a)干预效果的影响。方法:以慢病毒为载体转染TP基因至结肠癌细胞株LS174T,得到稳定传代的高TP表达株。将96只BALB/c裸鼠分成2组,分别应用野生型及转染TP基因后的LS174T细胞株接种裸鼠背部皮下,制成结肠癌TP低、高表达模型。每组再随机分为6组,分别应用0.9%Na Cl溶液、INF-α2a、5-FU、5-FU+INF-α2a、5’-DFUR和5’-DFUR+INF-α2a干预5 d,2周后处死裸鼠,分离肿瘤称重后,分别应用鼠抗人CD34、血管内皮生长因子(vascular endothelial growth factor,VEGF)和抗PD-ECGF单克隆抗体进行免疫组织化学染色。判定是否有TP表达及对微血管进行计数。结果:在野生型LS174T裸鼠荷瘤模型中,使用抗肿瘤药物的3~6组肿瘤质量与对照组相比均明显降低,抑癌率分别为48%、27%、48%和57%,差异有统计学意义(P<0.05)。其中5’-DFUR组(48%)与5’-DFUR+INF-α2a组(57%)、5-FU+INF-α2a组与5’-DFUR+INF-α2a组(27%与57%)相比,抑癌率差异有统计学意义(P<0.05)。在LS174T-TP细胞株裸鼠模型中,5’-DFUR组和5’-DFUR+INF-α2a组抑癌率分别为27%和48%,而使用5-FU的两组未显示出良好的抗肿瘤效果(7%和3%)。免疫组织化学染色显示,野生型LS174T接种形成的肿瘤组织中TP表达阴性,微血管数目较少,而转染TP基因后,肿瘤组织中TP表达明显上升,微血管密度明显增多(P<0.05)。结论:结肠癌细胞株LS174T转染TP基因后,在裸鼠实验肿瘤模型中,TP表达明显增加,使细胞内激活抗癌药物5’-DFUR的抗癌作用明显增强,联合应用INF-α2a能进一步增强这种抗癌作用。而转染TP基因或联合应用INF-α2a对常规抗癌药物5-FU的抗癌效Background and purpose： In colorectal cancer tissues, little thymidine phosphorylase （TP） expression was detected. In this study, the inhibitory effects of 5’-deoxy-5-fluorouridine （5’-DFUR） and 5-fluorouracil （5-FU） combined with interferon-α2a （INF-α2a） on nude mice transplanted with colorectal cancer cell line LS174T carrying TP cDNA were investigated. Methods： TP cDNA was transfected into human colorectal cancer cell line LS174T with lentiviral vector, and the LS174T cell line with high TP expression was obtained. Then 96 BALB/c nude mice were randomly divided into two groups. Wild LS174T and TP-transfected LS174T （LS174T-TP） cells were inoculated hypodermically into the nude mice back respectively to obtain the colorectal cancer graft models. Two days later, each group was randomly divided into 6 groups again, and different drug interventions were performed continuously for 5 days with normal saline, INF-α2a, 5-FU, 5-FU＋INF-α2a, 5’-DFUR and 5’-DFUR＋INF-α2a, respectively. All the nude mice were executed after 2 weeks, and tumor tissues were dissected and weighed. The tumor tissue specimens were immunohistochemically stained using the mouse anti-human CD34, VEGF and PDECGF monoclonal antibodies. And then the positive cells and microvessels were quantified respectively. Results： In all of the nude mice transplanted with wild LS174T, the tumor weights of those nude mice injected with antitumor drugs （group 3-6） were significantly lower compared with the control （normal saline）, and their tumor inhibition rates were 48%, 27%, 48% and 57% （P〈0.05）, respectively. Also the inhibition rates of those mice injected with 5’-DFUR, 5’-DFUR＋INF-α2a were 48% and 57%, respectively （P〈0.05）. The inhibition rates of the mice injected with 5-FU＋INF-α2a and 5＇-DFUR＋INF-α2a were 27% and 57%, respectively （P〈0.05）. In LS174T-TP-transplanted nude mice, the tumor inhibition rates of the mice injected with 5’-DFUR, 5’-DFUR＋INF-α2a were 27% and

关 键 词：结直肠癌 LS174T 胸苷磷酸化酶 5’-脱氧氟尿苷 干扰素-Α2A 

分 类 号：R735.35[医药卫生—肿瘤]