【摘要】 将互补于C-m yc mRNA的反义寡核苷酸(A SON)进行放射性碘(131I,125I)标记,通过多聚赖氨酸与血管活性肠肽(V IP)偶联形成放射性反义复合物(V IP1-31I-A SON,V IP1-25I-A SON)。以正义(SON)和无义链(M ON)作为对照,比较HT 29结肠癌细胞对125I-A SON和V IP1-25I-A SON的摄取率;利用M TT法和流式细胞计数仪检测C-m yc癌蛋白方法,研究131I-A SON和V IP1-31I-A SON对HT 29结肠癌细胞的作用。实验结果表明,与V IP结合后,125I-A SON在结肠腺癌HT 29细胞中的摄取率大大提高,与未结合125I-A SON摄取率相比差异显著(P<0.05)。V IP1-31I-A SON对HT 29细胞生长抑制作用呈剂量依赖型,且抑制作用显著强于其它各对照组(P<0.05)。流式细胞计数表明,与V IP1-31I-A SON组和131I-A SON组荧光强度明显低于其它各组(P<0.05),而V IP1-31I-A SON组的荧光强度又比131I-A SON组低(P<0.01),表明V IP作为载体,能有效将A SON导入结肠癌细胞,明显抑制HT 29结肠癌细胞的生长和C-m yc癌蛋白的表达。更多还原

【Abstract】 A 15-mer phosphorothioate antisense oligonucleotide（ASON） complementary to the translation start region of the C-myc oncogene mRNA was labeled with ¹³¹I or ¹²⁵I and the labelled compound was linked to the vasoactive intestinal peptide（VIP） to be bound covalently to a polylysine chain so as to deliver oligonucleotide into tumor cells.The effect of the VIP as carrier on cell uptake of ASON in tissue culture was evaluated in a human colon adenocarcinoma HT29 cell line.The efficacy of VIP-¹³¹I-ASON on cell growth was evaluated using the MTT assay.Expression of c-myc-encoded protein was measured by flow cytometry.Sense and nosense control Oligonucloeotides with VIP carrier were used as control.The results showed that VIP competed effectively with VIP-¹²⁵I-ASON to bind the HT29 cells.Cell uptake was increased 3-4 fold using the VIP carrier compared to the same dosage of naked DNA.HT29 cells treated with VIP-¹³¹I-ASON complexes exhibited 4-fold lower proliferation than those treated with ¹³¹I-ASON and 6-fold lower proliferation than those treated with radioiodinated Sense and nosense DNA.Cancer protein expression of HT29 cells treated with VIP-¹³¹I-ASON was decreased 2-fold compare with that in ¹³¹I-ASON treated cell.The use of a VIP carrier greatly increased ¹³¹I-ASON cellular uptake and inhibition of cell proliferation and C-myc cancer protein expressing in HT29 cell by radioiodinated antisense oligonuclide.更多还原