Tang Juxian, Chen Qi, Zhang Feng, Zhang Wenjun, Duan Sirong, Xiao Duan
Department of Hematology, Third Affiliated Hospital of Southern Medical University/Academy of Orthopedics of Guangdong Province, Guangzhou 510630, China.
2 Department of Rehabilitation, First Affiliated Hospital of Jinan University, Guangzhou 510632, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2019 Apr 30;39(4):485-489. doi: 10.12122/j.issn.1673-4254.2019.04.16.
To investigate the role of exosome in mediating bortezomib (Btz) resistance in multiple myeloma cells and explore the underlying mechanisms.
Peripheral blood samples were collected from 15 patients with multiple myeloma with Btz tolerance, and serum exosomes were isolated by ultracentrifugation and identified with electron microscopy, NTA and Western blotting. cultured multiple myeloma cells were treated with gradient concentrations of Btz to determine the optimal drug concentration for subsequent experiment. The cells were pretreated with different concentrations of exosomes, and their sensitivity to BTZ was assessed using MTS assay. We searched the exosome database Exocarta and used STRING to generate the network map and the protein interaction graph.
The diameters of the vesicles isolated from the peripheral blood of the patients were mostly below 200 nm with a mean particle size of 153 nm and a mode of 140.1 nm. The results of Western blotting showed that the isolated exosomes expressed the marker proteins CD63, Tsg101 and Alix. In cultured multiple myeloma cells, pretreatment with exosomes resulted in a decreased sensitivity of the cells to bortezomib, and longer treatment durations and higher exosome concentrations consistently enhanced the resistance of the cells to the same Btz concentration. Analysis of the Exocarta database identified human serum exosomal proteins ABCB1, ABCB4, PDCD6IP, and EGFR, among which EGFR served as a network node.
Exosome within a specific concentration range may serve as a signal carrier to mediate the resistance of multiple myeloma cells to Btz. EGFR likely plays a key role to promote exosome-mediated Btz resistance in myeloma cells.
探讨外泌体在介导多发性骨髓瘤细胞对硼替佐米（Btz）耐药中的作用并探索其潜在机制。
收集15例对Btz耐受的多发性骨髓瘤患者的外周血样本，通过超速离心分离血清外泌体，并用电子显微镜、纳米颗粒跟踪分析（NTA）和蛋白质免疫印迹法进行鉴定。用梯度浓度的Btz处理培养的多发性骨髓瘤细胞以确定后续实验的最佳药物浓度。细胞用不同浓度的外泌体预处理，然后用MTS法评估其对BTZ的敏感性。我们搜索了外泌体数据库Exocarta，并使用STRING生成网络图和蛋白质相互作用图。
从患者外周血中分离出的囊泡直径大多在200nm以下，平均粒径为153nm，众数为140.1nm。蛋白质免疫印迹结果显示，分离出的外泌体表达标志物蛋白CD63、Tsg101和Alix。在培养的多发性骨髓瘤细胞中，用外泌体预处理导致细胞对硼替佐米的敏感性降低，处理时间越长和外泌体浓度越高，细胞对相同浓度Btz的耐药性持续增强。对Exocarta数据库的分析确定了人血清外泌体蛋白ABCB1、ABCB4、PDCD6IP和EGFR，其中EGFR作为一个网络节点。
特定浓度范围内的外泌体可能作为信号载体介导多发性骨髓瘤细胞对Btz的耐药。EGFR可能在促进外泌体介导的骨髓瘤细胞对Btz耐药中起关键作用。
