Abstract：
The induction of heat stress response (HSR) mediated by the generation of heat shock proteins (HSPs) on exposure to magnetic hyperthermia-mediated cancer therapy (MHCT) decreases the efficacy of localized heat treatment at the tumor site, and thus therapy remains a significant challenge. Hence, the present study examined differential HSR elicited in glioma cells post-MHCT under different tumor microenvironment conditions (2D monolayers, 3D monoculture, and coculture spheroids) to recognize target genes that, when downregulated, could enhance the therapeutic effect of MHCT. Gene expression analysis following MHCT revealed that HSP90 was upregulated as compared to HSP70. Hence, to enhance the efficacy of the treatment, a combinatorial strategy using 17-DMAG as an inhibitor of HSP90 following MHCT was investigated. The effects of combinatorial therapy in terms of cell viability, HSP levels by immunofluorescence and gene expression analysis, oxidative stress generation, and alterations in cellular integrity were evaluated, where combinatorial therapy demonstrated an enhanced therapeutic outcome with maximum glioma cell death. Further, in the murine glioma model, a rapid tumor inhibition of 65 and 53% was observed within 8 days at the primary and secondary tumor sites, respectively, in the MCHT + 17-DMAG group, with abscopal effect-mediated complete tumor inhibition at both the tumor sites within 20 days of MHCT. The extracellularly released HSP90 from dying tumor cells further suggested the induction of immune response supported by the upregulation of IFN-γ and calreticulin genes in the MHCT + 17-DMAG group. Overall, our findings indicate that MHCT activates host immune systems and efficiently cooperates with the HSP90 blockade to inhibit the growth of distant metastatic tumors.
摘要：
通过热休克蛋白（HSP）的产生介导的热应激反应（HSR）的诱导暴露于磁热介导的癌症治疗（MHCT）降低了肿瘤部位局部热处理的功效，因此治疗仍然是一个重大挑战。因此，本研究检查了在不同肿瘤微环境条件下MHCT后在神经胶质瘤细胞中引起的差异HSR（2D单层，3D单一文化，和共培养球体)来识别目标基因，当下调时，可以增强MHCT的治疗效果。MHCT后的基因表达分析显示,与HSP70相比,HSP90上调。因此，为了提高治疗效果，研究了MHCT后使用17-DMAG作为HSP90抑制剂的组合策略。组合疗法对细胞活力的影响，HSP水平通过免疫荧光和基因表达分析，氧化应激的产生，并评估了细胞完整性的改变，其中组合疗法显示出增强的治疗结果，最大的神经胶质瘤细胞死亡。Further,在鼠神经胶质瘤模型中，在8天内在原发性和继发性肿瘤部位观察到65％和53％的快速肿瘤抑制，分别,在MCHT+17-DMAG组中，在MHCT的20天内，在两个肿瘤部位均具有abscopal效应介导的完全肿瘤抑制。从垂死的肿瘤细胞中释放的HSP90进一步表明，在MHCT17-DMAG组中，IFN-γ和钙网蛋白基因的上调支持了免疫反应的诱导。总的来说,我们的发现表明,MHCT激活宿主免疫系统,并与HSP90阻断剂有效合作,从而抑制远处转移肿瘤的生长.
