The Resorcylic Acid Lactone Hypothemycin Selectively Inhibits the Mitogen-Activated Protein Kinase Kinase-Extracellular Signal-Regulated Kinase Pathway in Cells
The Resorcylic Acid Lactone Hypothemycin Selectively Inhibits the Mitogen-Activated Protein Kinase Kinase-Extracellular Signal-Regulated Kinase Pathway in Cells
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DOI：
10.1248/bpb.33.168
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发表时间：
2010-02-01
影响因子：
2
通讯作者：
Uehara, Yoshimasa
中科院分区：
文献类型：
--
作者：
Fukazawa, Hidesuke;Ikeda, Yoshimi;Uehara, Yoshimasa
已显示间苯二甲酸内酯hypothemycin通过与46种蛋白激酶中保守的半胱氨酸结合来抑制蛋白激酶，包括促分裂原活化蛋白激酶激酶（MEK）、细胞外信号调节激酶（ERK）和血小板衍生生长因子受体（PDGFR）。我们评估了hypothemycin在细胞环境中的选择性。Hypothemycin正常化的形态和抑制锚定非依赖性生长的Ki-ras转化的正常大鼠肾（NRK）细胞的选择性和效力相当于或大于MEK抑制剂U 0126。在Ki-ras转化和佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）处理的NRK细胞中，hypothemycin阻断ERK激活，但对蛋白激酶D1（PKD 1）（另一种含有保守半胱氨酸的激酶）的自磷酸化作用甚微。在血小板衍生生长因子（PDGF）处理的NRK细胞中，Hypothemycin有效抑制PDGFR自磷酸化和MEK-ERK通路的激活。然而，磷酸肌醇-3-激酶（PI 3 K）途径仅适度减弱。Hypothemycin也抑制生长因子和锚定独立的人癌细胞系的生长与组成型活性MEK-ERK途径。虽然hypothemycin有可能抑制各种蛋白激酶，但结果表明，在细胞内环境中，hypothemycin可以抑制MEK-ERK轴，具有足够的选择性，使依赖于该途径的细胞转化表型正常化。
The resorcylic acid lactone hypothemycin has been shown to inactivate protein kinases by binding to a cysteine conserved in 46 protein kinases, including mitogen-activated protein kinase kinase (MEK), extracellular signal-regulated kinase (ERK) and platelet-derived growth factor receptor (PDGFR). We assessed the selectivity of hypothemycin in cellular contexts. Hypothemycin normalized the morphology and inhibited anchorage-independent growth of Ki-ras transformed normal rat kidney (NRK) cells with selectivity and potency comparable to or greater than that of the MEK inhibitor U0126. In Ki-ras-transformed and phorbol 12-myristate 13-acetate (PMA)-treated NRK cells, hypothemycin blocked ERK activation but showed a minimal effect on autophosphorylation of protein kinase D1 (PKD1), another kinase containing the conserved cysteine. Hypothemycin potently inhibited PDGFR autophosphorylation and activation of the MEK-ERK pathway in platelet-derived growth factor (PDGF)-treated NRK cells. However, the phosphoinositide-3-kinase (PI3K) pathway was only modestly attenuated. Hypothemycin also inhibited growth factor- and anchorage-independent growth of human cancer cell lines with a constitutively active MEK-ERK pathway. Although hypothemycin has the potential to inactivate various protein kinases, the results indicate that in intracellular environments, hypothemycin can inhibit the MEK-ERK axis with sufficient selectivity to normalize transformed phenotypes of cells dependent on this pathway.