Li Mei-Yong, Zhao Cui, Chen Lian, Yao Fang-Yi, Zhong Fang-Min, Chen Ying, Xu Shuai, Jiang Jun-Yao, Yang Yu-Lin, Min Qing-Hua, Lin Jin, Zhang Hai-Bin, Liu Jing, Wang Xiao-Zhong, Huang Bo
Jiangxi Province Key Laboratory of Laboratory Medicine, Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China.
Huanggang Central Hospital Affiliated to Changjiang University, Huanggang, China.
Front Oncol. 2021 Dec 21;11:779567. doi: 10.3389/fonc.2021.779567. eCollection 2021.
Imatinib (IM), a tyrosine kinase inhibitor (TKI), has markedly improved the survival and life quality of chronic myeloid leukemia (CML) patients. However, the lack of specific biomarkers for IM resistance remains a serious clinical challenge. Recently, growing evidence has suggested that exosome-harbored proteins were involved in tumor drug resistance and could be novel biomarkers for the diagnosis and drug sensitivity prediction of cancer. Therefore, we aimed to investigate the proteomic profile of plasma exosomes derived from CML patients to identify ideal biomarkers for IM resistance.
We extracted exosomes from pooled plasma samples of 9 imatinib-resistant CML patients and 9 imatinib-sensitive CML patients by ultracentrifugation. Then, we identified the expression levels of exosomal proteins by liquid chromatography-tandem mass spectrometry (LC-MS/MS) based label free quantification. Bioinformatics analyses were used to analyze the proteomic data. Finally, the western blot (WB) and parallel reaction monitoring (PRM) analyses were applied to validate the candidate proteins.
A total of 2812 proteins were identified in plasma exosomes from imatinib-resistant and imatinib-sensitive CML patients, including 279 differentially expressed proteins (DEPs) with restricted criteria (fold change≥1.5 or ≤0.667, p<0.05). Compared with imatinib-sensitive CML patients, 151 proteins were up-regulated and 128 proteins were down-regulated. Bioinformatics analyses revealed that the main function of the upregulated proteins was regulation of protein synthesis, while the downregulated proteins were mainly involved in lipid metabolism. The top 20 hub genes were obtained using STRING and Cytoscape, most of which were components of ribosomes. Moreover, we found that RPL13 and RPL14 exhibited exceptional upregulation in imatinib-resistant CML patients, which were further confirmed by PRM and WB.
Proteomic analysis of plasma exosomes provides new ideas and important information for the study of IM resistance in CML. Especially the exosomal proteins (RPL13 and RPL14), which may have great potential as biomarkers of IM resistance.
伊马替尼（IM）是一种酪氨酸激酶抑制剂（TKI），显著提高了慢性髓性白血病（CML）患者的生存率和生活质量。然而，缺乏针对IM耐药的特异性生物标志物仍然是一个严峻的临床挑战。最近，越来越多的证据表明，外泌体携带的蛋白质参与肿瘤耐药，并且可能成为癌症诊断和药物敏感性预测的新型生物标志物。因此，我们旨在研究CML患者血浆外泌体的蛋白质组学特征，以确定IM耐药的理想生物标志物。
我们通过超速离心从9例伊马替尼耐药CML患者和9例伊马替尼敏感CML患者的混合血浆样本中提取外泌体。然后，我们通过基于液相色谱-串联质谱（LC-MS/MS）的无标记定量法确定外泌体蛋白质的表达水平。使用生物信息学分析对蛋白质组学数据进行分析。最后，应用蛋白质印迹（WB）和平行反应监测（PRM）分析来验证候选蛋白。
在伊马替尼耐药和伊马替尼敏感CML患者的血浆外泌体中总共鉴定出2812种蛋白质，包括279种符合严格标准（倍数变化≥1.5或≤0.667，p<0.05）的差异表达蛋白（DEP）。与伊马替尼敏感CML患者相比，151种蛋白质上调，128种蛋白质下调。生物信息学分析显示，上调蛋白的主要功能是调节蛋白质合成，而下调蛋白主要参与脂质代谢。使用STRING和Cytoscape获得了前20个枢纽基因，其中大多数是核糖体的组成部分。此外，我们发现RPL13和RPL14在伊马替尼耐药CML患者中表现出异常上调，PRM和WB进一步证实了这一点。
血浆外泌体的蛋白质组学分析为CML中IM耐药的研究提供了新思路和重要信息。特别是外泌体蛋白（RPL13和RPL14），可能具有作为IM耐药生物标志物的巨大潜力。
