Jahchan et al. review myeloid cell types in the tumor microenvironment (TME) and clinical targeting strategies. Ontogeny, function, and key markers are discussed for primarily immune inhibitory (macrophages, monocytes, and granulocytes) and activating (dendritic cells) populations. Myeloid-targeting strategies attempt to modify recruitment to and proliferation in the TME (i.e. CCL2-CCR2 and CSF1-CSF1R) and functional phenotype (i.e. CD47-SIRPα, TLR, and CD40 agonists). Single-cell analysis is improving our understanding of the significant heterogeneity of myeloid cells in the TME and will aid development of therapeutic approaches.
Contributed by Alex Najibi
The tumor microenvironment (TME) of diverse cancer types is often characterized by high levels of infiltrating myeloid cells including monocytes, macrophages, dendritic cells, and granulocytes. These cells perform a variety of functions in the TME, varying from immune suppressive to immune stimulatory roles. In this review, we summarize the different myeloid cell populations in the TME and the intratumoral myeloid targeting approaches that are being clinically investigated, and discuss strategies that identify new myeloid subpopulations within the TME. The TME therapies include agents that modulate the functional activities of myeloid populations, that impact recruitment and survival of myeloid subpopulations, and that functionally reprogram or activate myeloid populations. We discuss the benefits, limitations and potential side effects of these therapeutic approaches.
Author Info: (1) Pionyr Immunotherapeutics, South San Francisco, CA, United States. (2) Department of Pathology, University of California, San Francisco, San Francisco, CA, United States. (3) P
Author Info: (1) Pionyr Immunotherapeutics, South San Francisco, CA, United States. (2) Department of Pathology, University of California, San Francisco, San Francisco, CA, United States. (3) Pionyr Immunotherapeutics, South San Francisco, CA, United States. (4) Pionyr Immunotherapeutics, South San Francisco, CA, United States. (5) Pionyr Immunotherapeutics, South San Francisco, CA, United States. (6) Pionyr Immunotherapeutics, South San Francisco, CA, United States. (7) Department of Pathology, University of California, San Francisco, San Francisco, CA, United States. ImmunoX Initiative, University of California, San Francisco, San Francisco, CA, United States.
