目的探讨反义寡核苷酸多位点封闭HBx基因对人类肝癌组织在裸小鼠皮下移植瘤发生的影响。方法50只裸小鼠随机等分为5组,1组为对照组,其余4组为实验组(AS1~AS4组),取对数期生长的内源性表达HBx蛋白的人类肝癌细胞系(Hep3B细胞)皮下注射,从第2天开始实验组分别通过腹膜腔内注射反义寡核苷酸AS1~AS4片段(剂量为10μg/g),隔日注射,共注射5次,对照组注射无菌双蒸馏水,观察裸小鼠皮下移植瘤生长情况,记录移植瘤潜伏期(从皮下注射肿瘤细胞至首次观察到皮下瘤结节),满30d实验终止,比较实验组和对照组移植瘤发生率,以生存分析模型分析移植瘤潜伏期在各组间的差异。结果实验组(AS1~AS3组)及对照组移植瘤发生率均为100%,AS4组10只小鼠中有1只小鼠实验结束时仍未观察到移植瘤的形成,各组小鼠移植瘤发生率差异无统计学意义。AS1~AS4组及对照组移植瘤潜伏期中位时间分别为19、12、11、21、10d,AS1、AS4组与对照组之间,差异有统计学意义(X2=40.94,P〈0.01)。结论反义寡核苷酸在恰当位点封闭HBx基因可以有效延长人类肝癌组织(Hep3B细胞系)在裸小鼠皮下移植瘤形成的潜伏期;但有限次数的干扰不能完全阻断移植瘤的发生;腹膜腔注射是反义寡核苷酸进入活体裸小鼠并发挥干扰作用的一条有效途径。
Objective To study the inhibitory effect ofHBx antisense oligodeoxynucleotide on the formation of transplanted hepatocellular carcinoma in nude mice. Method 50 nude mice were randomly divided into 5 groups: 1 control group and 4 experimental groups. Log-phase Hep3B cells endogenously expressing HBX were injected subcutaneously in nude mice. From the second day, the PAGE purified AS 1, AS2, AS3 and AS4 HBx antisense oligodeoxynucleotides were injected intraperitoneally into the 4 experimental groups, respectively, on alternate days for 5 times, and distilled water was injected into the control group. Growth information of subcutaneous transplantation tumor in nude mice was recorded for 30 days. Incidence rate of transplanted tumor in different groups was compared and analyzed by survival analysis. Statistics software SPSS12.0 was used to analyze the data. Results Incidence rate of transplanted tumor was 100% in AS1, AS2, AS3 and control groups, and 90% in AS4 group ( x2= 3.995, P = 1.0). The median latency period for transplanted tumor formation was 19 days (17.48-20.52), 12 days (9.93-14.07), 11 days (9.45-12.55), 21 days (19.48:22.52), and 10 days (8.99-11.01) in AS1, AS2, AS3, AS4 and control group, respectively. The latency period for tumor formation was prolonged by treatment of mice with AS 1 and AS4 antisense oligodeoxynucleotide (P 〈 0.01). Conclusion Antisense oligodeoxynucleotide targeting to the appropriate sites of HBx gene can prolong the latency period of subcutaneously transplanted tumor in nude mice, however, the formation of transplanted tumor can not be completely blocked by limited treatment with these antisense oligos. In addition, our results suggest that peritoneal injection may be an effective way to deliver antisense oligodeoxynucleotide to living organisms.