Title:Tumor-associated Macrophages (TAMs) in Cancer Resistance; Modulation
by Natural Products
Volume: 23
Issue: 12
Author(s): Holya A. Lafta, Ali H. AbdulHussein, Saif A. J. Al-Shalah, Yasir S. Alnassar, Naseer M. Mohammed, Sally M. Akram, Maytham T. Qasim and Masoud Najafi*
Affiliation:
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran
- Radiology and Nuclear Medicine Department, School of Paramedical Sciences, Kermanshah University of Medical Sciences, Kermanshah, Iran
Keywords:
Tumor-associated macrophages (TAMs), Tumor microenvironment (TME), Polarization, Immune system, Cancer, Flavonoids, Natural agents.
Abstract: Tumor-associated macrophages (TAMs) play a pivotal role in the progression and resistance
of tumors to different anticancer drugs. TAMs can modulate the tumor microenvironment
(TME) in favor of immune system exhaustion. The interactions of TAMs with TME can affect the
function of cytotoxic CD8+ T lymphocytes (CTLs) and natural killer (NK) cells. Furthermore,
TAMs can induce cancer cell proliferation by releasing some growth factors, such as transforming
growth factor (TGF)-β. TAMs have several positive cross-talks with other immune suppressive
cells such as regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), cancerassociated
fibroblasts (CAFs), and cancer cells, leading to the release of growth factors, the proliferation
of cancer cells and tumor growth. These interactions also can induce invasion and migration
of cancer cells, angiogenesis, and metastasis. The inhibition of TAMs is an intriguing strategy for
overcoming tumor resistance and suppression of cancer cells. Some natural-derived agents such as
melatonin, curcumin, resveratrol, apigenin, and other flavonoids have shown the ability to modulate
TME, including TAMs. These adjuvants may be able to boost antitumor immunity through the
modulation of TAMs. This review explains the modulatory effects of some well-known naturally
derived agents on the activity of TAMs. The modulation of TAMs by these agents may be useful in
suppressing tumor growth and invasion.
