5'-Cholesteryl-phosphorothioate oligodeoxynucleotides: potent inhibition of methotrexate transport and antagonism of methotrexate toxicity in cells containing the reduced-folate carrier.
5'-Cholesteryl-phosphorothioate oligodeoxynucleotides: potent inhibition of methotrexate transport and antagonism of methotrexate toxicity in cells containing the reduced-folate carrier.
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5-胆固醇硫代磷酸寡脱氧核苷酸：在含有还原叶酸载体的细胞中有效抑制甲氨蝶呤转运并拮抗甲氨蝶呤毒性。
DOI：
10.1093/nar/23.18.3726
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发表时间：
1995
影响因子：
14.9
通讯作者：
Stein,CA
中科院分区：
文献类型：
--
作者：
Henderson,GB;Stein,CA
研究了不同聚合物长度和核碱基组成的聚阴离子 5'-胆固醇硫代磷酸寡脱氧核苷酸对通过 L1210 小鼠细胞的还原叶酸载体转运甲氨蝶呤的影响。每种测试的寡脱氧核苷酸类似物均抑制甲氨蝶呤转运。对于由 15 个硫代磷酸脱氧核苷酸与交替的脱氧胞嘧啶和脱氧腺苷组成的 5'-胆固醇杂聚物 (ChoI-PS-d(CA)7C)，抑制最为明显（IC50= 0.21 μM，标准测定）。具有 15 个脱氧胞嘧啶的均聚物 (Chol-PS-dC15)。或脱氧胸苷(Chol-PS-dT15)残基的抑制性比Chol-PS-d(CA)7C低约2倍。不同长度的脱氧胞嘧啶寡聚物的转运抑制的相对效力为：Chol-PS-dC5>Chol-PS-dC15>Chol-PS-dC28>Chol-PS-dC3。在用抑制剂预孵育并在运输测定之前洗涤的细胞中保留了显着的抑制作用，并且可以通过降低细胞浓度来显着增加抑制剂的敏感性。观察到每种类似物的混合竞争性和非竞争性抑制。在标准高叶酸培养基中，Chol-PS-寡脱氧核苷酸（5.0 μM）对L1210细胞的生长影响最小，但拮抗甲氨蝶呤的细胞毒性。在 Chol-PS-d(CA)7C (IC50= 250 nM) 存在下，对甲氨蝶呤 (IC50=12 nM) 的反应降低到最大程度 (20.8 倍)。在叶酸有限的条件下，Chol-PS-d(CA)7C 单独抑制细胞生长，其过程可以被叶酸逆转。结果表明，Chol-PS-寡脱氧核苷酸是已知的最有效的还原叶酸载体抑制剂之一。对叶酸缺乏细胞的直接生长抑制和甲氨蝶呤细胞毒性的拮抗作用表明，Chol-PS-ollgodeoxynucleus 在培养细胞中保留了抑制叶酸还原载体数天的能力。
Polyanionic 5′-cholesteryl-phosphorothioate oligodeoxynucleotides of varying polymer length and nucleobase composition were examined for an effect on methotrexate transport via the reduced-folate carrier of L1210 mouse cells. Methotrexate transport was inhibited by each of the oligodeoxynucleotide analogs tested. Inhibition was most pronounced (IC50= 0.21 μM, standard assay) for a 5′-cholesteryl heteropolymer consisting of 15 phosphorothioate deoxynucleotides with alternating deoxycytosine and deoxyadenosine (ChoI-PS-d(CA)7C). Homopolymers with 15 deoxycytosine (Chol-PS-dC15). or deoxythymidine (Chol-PS-dT15) residues were ˜2-fold less inhibitory than Chol-PS-d(CA)7C. The relative potency of transport inhibition by deoxycytosine oligomers of varying length was: Chol-PS-dC5>Chol-PS-dC15>Chol-PS-dC28>Chol-PS-dC3. Substantial inhibition was retained in cells preincu bated with inhibitors and washed prior to transport determinations and the inhibitor sensitivity could be increased substantially by reducing the concentration of cells. Mixed competitive and non-competitive inhibition was observed for each analog. In standard high-folate medium, Chol-PS-oligodeoxynucleotides (5.0 μM) had minimal effects on the growth of L1210 cells, but antagonized the cytotoxicity of methotrexate. The response to methotrexate (IC50=12 nM) decreased to the greatest extent (20.8-fold) in the presence of Chol-PS-d(CA)7C (IC50= 250 nM). Under limiting folate conditions, Chol-PS-d(CA)7C alone inhibited cells growth by a process which could be reversed by folic acid. The results show that Chol-PS-oligodeoxynucleotides are among the most potent known inhibitors of the reduced-folate carrier. Direct growth inhibition of folate-deficient cells and antagonism of methotrexate cytotoxicity indicate that Chol-PS-ollgodeoxynucleotides retain the ability to inhibit the reduced-folate carrier for several days in cultured cells.