Lanza Marika, Casili Giovanna, Campolo Michela, Paterniti Irene, Colarossi Cristina, Mare Marzia, Giuffrida Raffella, Caffo Maria, Esposito Emanuela, Cuzzocrea Salvatore
Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno D'Alcontres, 98166 Messina, Italy.
Mediterranean Institute of Oncology, Via Penninazzo 7, 95029 Viagrande, Italy.
Brain Sci. 2021 Apr 7;11(4):466. doi: 10.3390/brainsci11040466.
Microglia, a type of differentiated tissue macrophage, are considered to be the most plastic cell population of the central nervous system (CNS). Microglia substantially contribute to the growth and invasion of tumor mass in brain tumors including glioblastoma (GB). In response to pathological conditions, resting microglia undergo a stereotypic activation process and become capable of phagocytosis, antigen presentation, and lymphocyte activation. Considering their immune effector function, it is not surprising to see microglia accumulation in almost every CNS disease process, including malignant brain tumors. Large numbers of glioma associated microglia and macrophages (GAMs) can accumulate within the tumor where they appear to have an important role in prognosis. GAMs constitute the largest portion of tumor infiltrating cells, contributing up to 30% of the entire glioma mass and upon interaction with neoplastic cells. GAMs acquire a unique phenotype of activation, including both M1 and M2 specific markers. It has been demonstrated that microglia possess a dual role: on one hand, microglia may represent a CNS anti-tumor response, which is inactivated by local secretion of immunosuppressive factors by glioma cells. On the other hand, taking into account that microglia are capable of secreting a variety of immunomodulatory cytokines, it is possible that they are attracted by gliomas to promote tumor growth. A better understanding of microglia-glioma interaction will be helpful in designing novel immune-based therapies against these fatal tumors. Concluding, as microglia significantly may contribute to glioma biology, favoring tumor growth and invasiveness, these cells represent a valuable alternative/additional target for the development of more effective treatments for gliomas.
小胶质细胞是一种分化的组织巨噬细胞，被认为是中枢神经系统（CNS）中最具可塑性的细胞群体。小胶质细胞在包括胶质母细胞瘤（GB）在内的脑肿瘤中对肿瘤块的生长和侵袭起着重要作用。在病理条件下，静息的小胶质细胞会经历一个刻板的激活过程，并变得能够进行吞噬作用、抗原呈递和淋巴细胞激活。考虑到它们的免疫效应功能，在几乎每一种中枢神经系统疾病过程中，包括恶性脑肿瘤，都能看到小胶质细胞的积累也就不足为奇了。大量的胶质瘤相关小胶质细胞和巨噬细胞（GAMs）会在肿瘤内积聚，它们似乎在预后中起着重要作用。GAMs构成肿瘤浸润细胞的最大部分，占整个胶质瘤肿块的30%，并且在与肿瘤细胞相互作用时发挥作用。GAMs获得了一种独特的激活表型，包括M1和M2特异性标志物。已经证明小胶质细胞具有双重作用：一方面，小胶质细胞可能代表中枢神经系统的抗肿瘤反应，但这种反应会被胶质瘤细胞局部分泌的免疫抑制因子所灭活。另一方面，考虑到小胶质细胞能够分泌多种免疫调节细胞因子，它们有可能被胶质瘤吸引以促进肿瘤生长。更好地理解小胶质细胞与胶质瘤的相互作用将有助于设计针对这些致命肿瘤的新型免疫疗法。总之，由于小胶质细胞可能对胶质瘤生物学有显著贡献，促进肿瘤生长和侵袭，这些细胞代表了开发更有效治疗胶质瘤的有价值的替代/额外靶点。
