Dabbah Mahmoud, Attar-Schneider Oshrat, Tartakover Matalon Shelly, Shefler Irit, Jarchwsky Dolberg Osnat, Lishner Michael, Drucker Liat
Oncogenetic, Meir Medical Center, Kfar Saba, Israel.
Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Carcinogenesis. 2017 Jul 1;38(7):708-716. doi: 10.1093/carcin/bgx045.
Multiple myeloma (MM) cells' interaction with the bone marrow (BM) microenvironment critically hinders disease therapy. Previously, we showed that MM co-culture with BM-mesenchymal stem cells (MSCs) caused co-modulation of translation initiation (TI) and cell phenotype and implicated secreted components, specifically microvesicles (MVs). Here, we studied the role of the BM-MSCs [normal donors (ND) and MM] secreted MVs in design of MM cells' phenotype, TI and signaling. BM-MSCs' MVs collected from BM-MSCs (MM/ND) cultures were applied to MM cell lines. After MVs uptake confirmation, the MM cells were assayed for viability, cell count and death, proliferation, migration, invasion, autophagy, TI status (factors, regulators, targets) and MAPKs activation. The interdependence of MAPKs, TI and autophagy was determined (inhibitors). ND-MSCs MVs' treated MM cells demonstrated a rapid (5 min) activation of MAPKs followed by a persistent decrease (1-24 h), while MM-MSCs MVs' treated cells demonstrated a rapid and continued (5 min-24 h) activation of MAPKs and TI (↑25-200%, P < 0.05). Within 24 h, BM-MSCs MVs were internalized by MM cells evoking opposite responses according to MVs origin. ND-MSCs' MVs decreased viability, proliferation, migration and TI (↓15-80%; P < 0.05), whereas MM-MSCs' MVs increased them (↑10-250%, P < 0.05). Inhibition of MAPKs in MM-MSCs MVs treated MM cells decreased TI and inhibition of autophagy elevated cell death. These data demonstrate that BM-MSCs MVs have a fundamental effect on MM cells phenotype in accordance with normal or pathological source implemented via TI modulation. Future studies will aim to elucidate the involvement of MVs-MM receptor ligand interactions and cargo transfer in our model.
多发性骨髓瘤（MM）细胞与骨髓（BM）微环境的相互作用严重阻碍了疾病治疗。此前，我们发现MM与BM间充质干细胞（MSCs）共培养会导致翻译起始（TI）和细胞表型的共同调节，并暗示了分泌成分，特别是微泡（MVs）的作用。在此，我们研究了BM-MSCs（正常供体[ND]和MM）分泌的MVs在MM细胞表型、TI和信号传导设计中的作用。将从BM-MSCs（MM/ND）培养物中收集的BM-MSCs的MVs应用于MM细胞系。在确认MVs摄取后，检测MM细胞的活力、细胞计数与死亡、增殖、迁移、侵袭、自噬、TI状态（因子、调节因子、靶点）以及丝裂原活化蛋白激酶（MAPKs）的激活情况。确定了MAPKs、TI和自噬之间的相互依赖性（使用抑制剂）。经ND-MSCs的MVs处理的MM细胞显示MAPKs迅速激活（5分钟），随后持续下降（1 - 24小时），而经MM-MSCs的MVs处理的细胞则显示MAPKs和TI迅速且持续激活（5分钟 - 24小时）（升高25 - 200%，P < 0.05）。在24小时内，BM-MSCs的MVs被MM细胞内化，根据MVs来源引发相反的反应。ND-MSCs的MVs降低了活力、增殖、迁移和TI（降低15 - 80%；P < 0.05），而MM-MSCs的MVs则使其增加（升高10 - 250%，P < 0.05）。在经MM-MSCs的MVs处理的MM细胞中抑制MAPKs会降低TI，抑制自噬会增加细胞死亡。这些数据表明，BM-MSCs的MVs通过TI调节，根据正常或病理来源对MM细胞表型产生根本性影响。未来的研究旨在阐明我们模型中MVs-MM受体配体相互作用和货物转运的参与情况。
