Roles of tumor-associated macrophages in tumor progression: implications on therapeutic strategies

• Published in: Experimental hematology & oncology Vol. 10; no. 1; p. 60
• Main Authors: Zhu, Shuangli, Yi, Ming, Wu, Yuze, Dong, Bing, Wu, Kongming
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 29.12.2021; BioMed Central; BMC
• Subjects: Angiogenesis; B cells; Bone marrow; Cancer; Cell growth; Chemokines; Cytokines; Development and progression; Disease; Epidermal growth factor; Genotype & phenotype; Health aspects; Hypoxia; Immunotherapy; Inflammation; Ligands; Lung cancer; Macrophages; Metastasis; Review; Therapeutic strategies; Tumor necrosis factor-TNF; Tumor progression; Tumor-associated macrophages; Tumorigenesis; Tumors; Vascular endothelial growth factor; Tumor-associated macrophages; Therapeutic strategies; Tumor progression
• ISSN: 2162-3619; 2162-3619
• DOI: 10.1186/s40164-021-00252-z

Macrophages are heterogeneous cells that present as different functional phenotypes due to their plasticity. They can be classified into two categories, namely M1- and M2-like macrophages, which are involved in processes as diverse as anti-tumor activity and immunosuppressive tumor promotion. Tumor-associated macrophages (TAMs) are defined as being of an M2-type and are considered as the active component in tumor microenvironment. TAMs are involved in multiple processes of tumor progression through the expression of cytokines, chemokines, growth factors, protein hydrolases and more, which lead to enhance tumor cell proliferation, angiogenesis, and immunosuppression, which in turn supports invasion and metastasis. It is assumed that the abundance of TAMs in major solid tumors is correlated to a negative patient prognosis. Because of the currently available data of the TAMs' role in tumor development, these cells have emerged as a promising target for novel cancer treatment strategies. In this paper, we will briefly describe the origins and types of TAMs and will try to comprehensively show how TAMs contribute to tumorigenesis and disease progression. Finally, we will present the main TAM-based therapeutic strategies currently available.