Role of macrophages in tumor progression and therapy (Review)

Int J Oncol. 2022 May;60(5):57. doi: 10.3892/ijo.2022.5347. Epub 2022 Apr 1.

Abstract

The number and phenotype of macrophages are closely related to tumor growth and prognosis. Macrophages are recruited to (and polarized at) the tumor site thereby promoting tumor growth, stimulating tumor angiogenesis, facilitating tumor cell migration, and creating a favorable environment for subsequent colonization by (and survival of) tumor cells. These phenomena contribute to the formation of an immunosuppressive tumor microenvironment (TME) and therefore speed up tumor cell proliferation and metastasis and reduce the efficacy of antitumor factors and therapies. The ability of macrophages to remodel the TME through interactions with other cells and corresponding changes in their number, activity, and phenotype during conventional therapies, as well as the association between these changes and drug resistance, make tumor‑associated macrophages a new target for antitumor therapies. In this review, advantages and limitations of the existing antitumor strategies targeting macrophages in Traditional Chinese and Western medicine were analyzed, starting with the effect of macrophages on tumors and their interactions with other cells and then the role of macrophages in conventional treatments was explored. Possible directions of future developments in this field from an all‑around multitarget standpoint were also examined.

Keywords: antitumor strategy; immunity cells; targeted therapy; tumor microenvironment; tumor‑associated macrophage.

Publication types

  • Review

MeSH terms

  • Cell Proliferation
  • Humans
  • Macrophages / pathology
  • Neoplasms* / pathology
  • Neovascularization, Pathologic / pathology
  • Tumor Microenvironment*

Grants and funding

This study was supported by the National Natural Science Foundation of China (grant nos. 82174222 and 81973677).