Table 1.

Signals involved in the interaction of TAMs with tumor cells

Signaling pathways	Modulation of TAMs	Regulation of tumor cells	Functions
WNT signaling pathway	Wnt signaling-inducible proteins released from tumor cells mediate TAMs recruitment and m2-like polarization	Wnt proteins released from TAMs augment the stemness of tumor cells through a β-catenin-dependent pathway and promote the invasiveness of tumor cells through a β-catenin-independent pathway	Facilitates tumor advancement through β-catenin-dependent and β-catenin-independent pathways; Wnt5a promotes tumor cell invasion through an atypical pathway
PI3K signaling pathway	Various cytokines, including EGFR, activate the PI3K pathway and contribute to the recruitment of TAMs and their polarization to the M2 phenotype, providing a suitable environment for tumor progression	Tumor cells release succinate via the pi3k-hypoxia inducible factor 1a (HIF1A) axis, thus promoting macrophage transformation	Enhance the proliferation, differentiation and migration of tumor cells
STAT3 signaling pathway	Activation of JAK3/STAT3 pathway and secretion of IL-6 and IL-10 induce TAMs to M2 polarization	IL-6 secreted by TAMs activates the JAK2/STAT3 pathway, which stimulates tumor cell invasion and metastasis	Enhancement of tumor proliferation, invasion and metastasis
NF-kB signaling pathway	Decreased phosphorylation of RELA protein stimulates TAMs to M2 polarization	Cytokines secreted by M2 enhance TNF and iNOS expression in tumor cells, resulting in activation of the NF-kB pathway	Inhibition of apoptosis of tumor cells and promotion of tumor angiogenesis and metastasis
Exosome signaling	Exosomes secreted by TAMs promote tumor neoangiogenesis and tumor cell invasiveness	Tumor cell-derived exosomes promote tumor progression by activating TAMs	Mediates communication between tumor cells and TAMs to create conditions for tumor cell survival and development