Identification of potential pharmacological and toxicological targets differentiating structural analogs by a combination of transcriptional profiling and promoter analysis in LS-180 and Caco-2 adenocarcinoma cell lines
Identification of potential pharmacological and toxicological targets differentiating structural analogs by a combination of transcriptional profiling and promoter analysis in LS-180 and Caco-2 adenocarcinoma cell lines
复制标题
DOI：
10.1097/01.fpc.0000220561.59972.7a
复制
发表时间：
2006-08-01
影响因子：
2.6
通讯作者：
Evans, David C.
中科院分区：
文献类型：
--
作者：
Hartley, Dylan R.;Dai, Xudong;Evans, David C.
检测和理解脱靶药理学作用的潜力对于药物发现计划中的先导化合物的优化至关重要。通常监测化合物介导的对药物代谢基因的关键调节剂-在反式激活试验中，两种结构类似物MRL-11和MRL-2被确定为等效的PXR激活剂。为了区分这两种PXR激活剂，在PXR充足（LS 180）和PXR缺陷（Caco-2）腺癌细胞系中检查了它们的转录作用。这两种化合物在LS 180细胞中调节药物管理基因（例如CYP 3A 4，CYP 2B 6，UGT 1A 1和ABCB 1），但在PXR缺陷的Caco-2细胞中很热。MRL-11和MRL-2对PXR激活的效力再次等同，如在LS 180细胞中由四种原型PXR激动剂（利福平、利托那韦、曲格列酮和地塞米松）调节的一组113个基因所揭示的。通过基于序列的启动子分析发现的推定PXR结合位点的富集支持PXR特征基因的特异性。有趣的是，MRL-2的额外脱靶活性被提出，其中发现固醇反应元件结合蛋白结合位点在PXR特征基因的子集中富集。这些参与胆固醇和脂肪酸合成的基因受到利托那韦、氯丙嗪和MRL-2的显著调节，这些基因与磷脂质病的表现有关。本研究证明了我们的方法在药物开发的先导化合物的分化和选择中的实用性。
Detecting and understanding the potential for off-target pharmacological effects is critical in the optimization of lead compounds in drug discovery programs. Compound-mediated activation of the pregnane X receptor (PXR; NR1/2), a key regulator for drug metabolism genes, is often monitored to avoid potential drug-drug interactions. Two structural analogs, MRL-11 and MRL-2, were determined to be equivalent PXR activators in trans-activation assays. To differentiate these two PXR activators, their transcriptional effects were examined in PXR-sufficient (LS180) and PXR-deficient (Caco-2) adenocarcinoma cell lines. Both compounds regulated drug-management genes (e.g. CYP3A4, CYP2B6, UGT1A1 and ABCB1) in LS180 cells, but hot in PXR-deficient Caco-2 cells. The potency of MRL-11 and MRL-2 on PXR activation was again equivalent as revealed by a set of 113 genes that were regulated by four prototypical PXR agonists (rifampicin, ritonavir, troglitazone and dexamethasone) in the LS180 cells. The specificity of the PXR signature genes was supported by the enrichment of putative PXR binding sites uncovered by sequence-based promoter analyses. Interestingly, an additional off-target activity of MRL-2 was suggested where sterol response element binding protein binding sites were found enriched in a subset of PXR signature genes. These genes, involved in cholesterol and fatty acid synthesis, were significantly regulated by ritonavir, chlorpromazine and MRL-2, which were linked to the manifestation of phospholipidosis. The present study demonstrates the utility of our approach in the differentiation and selection of lead compounds for drug development.