Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.
Front Immunol. 2021 Oct 4;12:746621. doi: 10.3389/fimmu.2021.746621. eCollection 2021.
Though significant strides in tumorigenic comprehension and therapy modality have been witnessed over the past decades, glioma remains one of the most common and malignant brain tumors characterized by recurrence, dismal prognosis, and therapy resistance. Immunotherapy advance holds promise in glioma recently. However, the efficacy of immunotherapy varies among individuals with glioma, which drives researchers to consider the modest levels of immunity in the central nervous system, as well as the immunosuppressive tumor immune microenvironment (TIME). Considering the highly conserved property for sustaining energy homeostasis in mammalian cells and repeatedly reported links in malignancy and drug resistance, autophagy is determined as a cutting angle to elucidate the relations between glioma and the TIME. In this review, heterogeneity of TIME in glioma is outlined along with the reciprocal impacts between them. In addition, controversies on whether autophagy behaves cytoprotectively or cytotoxically in cancers are covered. How autophagy collapses from its homeostasis and aids glioma malignancy, which may depend on the cell type and the cellular context such as reactive oxygen species (ROS) and adenosine triphosphate (ATP) level, are briefly discussed. The consecutive application of autophagy inducers and inhibitors may improve the drug resistance in glioma after overtreatments. It also highlights that autophagy plays a pivotal part in modulating glioma and the TIME, respectively, and the intricate interactions among them. Specifically, autophagy is manipulated by either glioma or tumor-associated macrophages to conform one side to the other through exosomal microRNAs and thereby adjust the interactions. Given that some of the crosstalk between glioma and the TIME highly depend on the autophagy process or autophagic components, there are interconnections influenced by the status and well-being of cells presumably associated with autophagic flux. By updating the most recent knowledge concerning glioma and the TIME from an autophagic perspective enhances comprehension and inspires more applicable and effective strategies targeting TIME while harnessing autophagy collaboratively against cancer.
尽管在过去几十年中,在肿瘤发生理解和治疗方式方面取得了重大进展,但胶质瘤仍然是最常见和恶性的脑肿瘤之一,其特点是复发、预后不良和治疗耐药。免疫治疗的进展最近在胶质瘤中具有前景。然而,免疫疗法在胶质瘤个体中的疗效不同,这促使研究人员考虑中枢神经系统中适度的免疫水平以及免疫抑制性肿瘤免疫微环境 (TIME)。考虑到维持哺乳动物细胞能量平衡的高度保守特性以及恶性肿瘤和耐药性之间反复报道的联系,自噬被确定为阐明胶质瘤与 TIME 之间关系的切入点。在这篇综述中,概述了胶质瘤中 TIME 的异质性以及它们之间的相互影响。此外,还涵盖了自噬在癌症中是表现为细胞保护还是细胞毒性的争议。自噬如何从其平衡状态崩溃并有助于胶质瘤恶性肿瘤,这可能取决于细胞类型和细胞环境,如活性氧 (ROS) 和三磷酸腺苷 (ATP) 水平,简要讨论了。自噬诱导剂和抑制剂的连续应用可能会改善过度治疗后胶质瘤的耐药性。它还强调了自噬分别在调节胶质瘤和 TIME 以及它们之间的复杂相互作用中起着关键作用。具体而言,自噬通过胶质瘤或肿瘤相关巨噬细胞通过外泌体 microRNAs 相互作用来调节另一侧,从而调整相互作用。鉴于胶质瘤和 TIME 之间的一些串扰高度依赖于自噬过程或自噬成分,因此存在受细胞状态和健康状况影响的相互联系,这些细胞可能与自噬流有关。通过从自噬角度更新关于胶质瘤和 TIME 的最新知识,增强了对它们的理解,并激发了更多针对 TIME 的实用且有效的策略,同时协同利用自噬来对抗癌症。