Burgess T L, Fisher E F, Ross S L, Bready J V, Qian Y X, Bayewitch L A, Cohen A M, Herrera C J, Hu S S, Kramer T B
Department of Mammalian Cell Molecular Biology, Amgen Inc., Amgen Center, Thousand Oaks, CA 91320-1789, USA.
Proc Natl Acad Sci U S A. 1995 Apr 25;92(9):4051-5. doi: 10.1073/pnas.92.9.4051.
Smooth muscle cell (SMC) proliferation is thought to play a major role in vascular restenosis after angioplasty and is a serious complication of the procedure. Developing antisense (AS) oligonucleotides as therapeutics is attractive because of the potentially high specificity of binding to their targets, and several investigators have reported inhibition of SMC proliferation in vitro and in vivo by using AS strategies. We report here the results of our experiments on vascular SMCs using AS oligonucleotides directed toward c-myb and c-myc. We found that significant inhibition of SMC proliferation occurred with these specific AS sequences but that this inhibition was clearly not via a hybridization-dependent AS mechanism. Rather, inhibition was due to the presence of four contiguous guanosine residues in the oligonucleotide sequence. This was demonstrated in vitro in primary cultures of SMCs and in arteries ex vivo. The ex vivo model developed here provides a rapid and effective system in which to screen potential oligonucleotide drugs for restenosis. We have further explored the sequence requirements of this non-AS effect and determined that phosphorothioate oligonucleotides containing at least two sets of three or four consecutive guanosine residues inhibit SMC proliferation in vitro and ex vivo. These results suggest that previous AS data obtained using these and similar, contiguous guanosine-containing AS sequences be reevaluated and that there may be an additional class of nucleic acid compounds that have potential as antirestenosis therapeutics.
平滑肌细胞（SMC）增殖被认为在血管成形术后的血管再狭窄中起主要作用，并且是该手术的严重并发症。开发反义（AS）寡核苷酸作为治疗药物很有吸引力，因为其与靶点结合具有潜在的高特异性，并且几位研究人员报告了使用AS策略在体外和体内抑制SMC增殖。我们在此报告了我们使用针对c-myb和c-myc的AS寡核苷酸对血管SMC进行实验的结果。我们发现，这些特定的AS序列可显著抑制SMC增殖，但这种抑制显然不是通过杂交依赖性AS机制实现的。相反，抑制是由于寡核苷酸序列中存在四个连续的鸟苷残基。这在SMC原代培养物和离体动脉中得到了体外验证。这里开发的离体模型提供了一个快速有效的系统，用于筛选潜在的抗再狭窄寡核苷酸药物。我们进一步探索了这种非AS效应的序列要求，并确定含有至少两组三个或四个连续鸟苷残基的硫代磷酸寡核苷酸在体外和离体条件下均能抑制SMC增殖。这些结果表明，之前使用这些以及类似的、含连续鸟苷的AS序列获得的AS数据需要重新评估，并且可能存在另一类具有抗再狭窄治疗潜力的核酸化合物。
