Brefeldin A Induces Apoptosis, Inhibits BCR-ABL Activation, and Triggers BCR-ABL Degradation in Chronic Myeloid Leukemia K562 Cells.
Brefeldin A Induces Apoptosis, Inhibits BCR-ABL Activation, and Triggers BCR-ABL Degradation in Chronic Myeloid Leukemia K562 Cells.
复制标题
Brefeldin A 在慢性粒细胞白血病 K562 细胞中诱导细胞凋亡、抑制 BCR-ABL 激活并触发 BCR-ABL 降解。
DOI：
10.2174/1871520621666210608110435
复制
发表时间：
2021-06
期刊：
影响因子：
--
通讯作者：
Liu Ming
中科院分区：
文献类型：
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作者：
Zhang Jin-Man;Wang Cui-Fang;Wei Mei-Yan;Dong Hui;Gu Yu-Cheng;Mo Xiao-Mei;Shao Chang-Lun;Liu Ming
背景
慢性粒细胞白血病(CML)是由bcr-abl癌蛋白引起的一种骨髓增生性疾病。酪氨酸激酶抑制剂已被开发用于抑制bcr-abl的活性，但在临床应用中会出现耐药性和副作用。因此，寻找治疗慢性粒细胞白血病的新药迫在眉睫。在细胞毒活性的指导下，对55株药用红树植物刺五加真菌的粗提物进行了鉴定，从青霉菌中发现了一种有效的细胞毒性天然化合物布雷菲尔丁A(BFA)。(HS-N-29)。
客观化
本研究旨在探讨BFA的细胞毒活性及其对K562细胞bcr-abl活化和表达的影响。
方法
用四甲基偶氮唑盐比色法和软琼脂克隆法检测细胞毒活性，用MUSE细胞分析仪检测细胞凋亡率和细胞周期分布。Western blotting检测bcr-abl及信号分子的蛋白水平，RT-PCR检测bcr-abl的mRNA水平。
结果
BFA抑制K562细胞增殖，诱导细胞周期停滞于G2/M期，并促进细胞凋亡。重要的是，我们首次揭示了BFA抑制了K562细胞中bcr-abl的激活，从而抑制了其下游信号分子的激活。此外，我们还发现BFA在K562细胞中降解BCR-ABL而不影响其转录，BFA诱导的BCR-ABL降解与caspase激活有关，而与自噬或泛素化的蛋白酶体降解途径无关。
结论
我们的研究结果表明，BFA是BCR-ABL的双功能抑制剂和降解物，BFA是一种潜在的抗慢性粒细胞白血病化疗药物。
BACKGROUND
Chronic myeloid leukemia (CML) is a myeloproliferative disease caused by BCR-ABL oncoprotein. Tyrosine kinase inhibitors have been developed to inhibit the activity of BCR-ABL; however, drug resistance and side effect occur in clinic application. Therefore, it is urgent to find novel drugs for CML treatment. Under the guidance of cytotoxic activity, crude extracts of 55 fungal strains from the medicinal mangrove Acanthus ilicifolius were evaluated, and one potent cytotoxic natural compound, brefeldin A (BFA), was discovered from Penicillium sp. (HS-N-29).
OBJECTIVE
This study was aimed to determine the cytotoxic activity of BFA and the effect on the activation and expression of BCR-ABL in K562 cells.
METHOD
We evaluated cytotoxic activity by MTT assay and soft agar clone assay and apoptosis and cell cycle distribution by Muse cell analyzer. The protein level of BCR-ABL and signaling molecules were detected by western blotting, and the mRNA level of BCR-ABL was determined by RT-PCR.
RESULTS
BFA inhibited cell proliferation, induced G2/M cell cycle arrest, and stimulated cell apoptosis in K562 cells. Importantly, for the first time, we revealed that BFA inhibited the activation of BCR-ABL and consequently inhibited the activation of its downstream signaling molecules in K562 cells. Moreover, we found that BFA degraded BCR-ABL without affecting its transcription in K562 cells, and BFA-induced BCR-ABL degradation was related to caspase activation while not to autophagy or ubiquitinated proteasome degradation pathway.
CONCLUSION
Our present results indicate that BFA acts as a dual functional inhibitor and degrader of BCR-ABL, and BFA is a potential compound for chemotherapeutics to overcome CML.