Enhancement of 5-fluorouracil sensitivity by an rTS signaling mimic in H630 colon cancer cells
Enhancement of 5-fluorouracil sensitivity by an rTS signaling mimic in H630 colon cancer cells
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DOI：
10.1158/0008-5472.can-05-0431
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发表时间：
2005-07-01
期刊：
影响因子：
11.2
通讯作者：
Dolnick, BJ
中科院分区：
文献类型：
--
作者：
Dolnick, R;Wu, Q;Dolnick, BJ
已经假设RTSβ蛋白可以合成可以下调胸苷酸合酶的信号分子。这些分子与酰基 - 耶洛舍碱内酯（AHL）具有生物学和化学特性，表明某些AHL可能充当RTS信号模拟物和下调胸苷基合酶。我们已经确定，AHL 3-氧化烷酰均hom雀内酯（3-氧基-C12-（L）HSL）可以在10 Mu mol/L处下调胸苷合成蛋白，并降低H630（人类结直肠癌）的生长50％在细胞培养中的23 mu mol/L（IC50）。在其IC50浓度下，3-氧气-CI2-（L）-HSL将5-氟尿嘧啶（5-FU）的明显IC50从1 mu mol/L到80 nmol/l（12倍），在菌落形成测定中。 3-oxo-c12-（l）-HSL增强了5-氟脱氧尿苷，tomudex和紫杉醇的活性，但不能增强5-氟嘧啶，甲氨蝶呤或阿霉素的活性。与紫杉醇的意外相互作用可能是由于AHL对微管蛋白表达的影响而导致的。 H630和胸苷酸合酶和RTSβ-抗β-抗β-耐β-耐苯二甲酸酯合成酶之间的紫杉醇敏感性，微管蛋白和细胞形态的差异，通过菌落形成测定确定的5-FU H630-1细胞系，西方对一维和二维GELS的分析，光显微镜证实，AHL或RTS信号传导诱导细胞骨架变化。胸苷酸合酶和RT的lsozyme差异也存在于两种细胞系中。 RTS氨基酸S 121的磷酸化已显示出发生，并且在药物耐药细胞中至少降低了10倍。提供的数据为RTS信号传导模拟物的进一步研究提供了支持，作为胸苷合成酶指导的化学疗法的增强子，证明RTSβ的磷酸化状态可能是5-FU耐药性和先前未实现的RTS信号传导与细胞骨架之间未实现的关系的标志。
The rTS beta protein has been hypothesized to synthesize signaling molecules that can down-regulate thymidylate synthase. These molecules share biological and chemical properties with acyl-homoserine lactones (AHL), suggesting some AHLs might act as rTS signaling mimics and down-regulate thymidylate synthase. We have determined that the AHL, 3-oxododecanoyl homoserine lactone (3-oxo-C12-(L)HSL) can down-regulate thymidylate synthase protein at 10 mu mol/l, and reduce H630 (human colorectal cancer) growth by 50% at 23 mu mol/L (IC50) in cell culture. At its IC50 concentration, 3-oxo-CI2-(L)-HSL reduces the apparent IC50 of 5-fluorouracil (5-FU) from 1 mu mol/L to 80 nmol/L (12-fold) in a colony formation assay. 3-Oxo-C12-(L)-HSL enhances the activity of 5-fluorodeoxyuridine, tomudex, and taxol but not the activity of 5-fluorouridine, methotrexate or Adriamycin. The unexpected interaction with taxol probably results from effects of the AHL on tubulin expression. Differences in taxol sensitivity, tubulin, and cellular morphology between H630 and the thymidylate synthase and rTS beta-overproducing, 5-FU-resistant H630-1 cell line as determined by colony formation assays, Western analysis of one-dimensional and two-dimensional gels, and photomicroscopy confirm that cytoskeletal changes are induced by the AHL or by rTS signaling. lsozyme differences in thymidylate synthase and rTS also exist in the two cell lines. Phosphorylation of rTS amino acid S 121 is shown to occur and is decreased at least 10-fold in the drug-resistant cells. The data presented provide support for further investigations of rTS signaling mimics as enhancers to thymidylate synthase-directed chemotherapy, evidence that the phosphorylation state of rTS beta may be a marker for 5-FU resistance and a previously unrealized relationship between rTS signaling and the cytoskeleton.