Table 1 Key inflammatory cells in cancer with antitumor or protumoral activities

Tumor-associated neutrophils (TANs)

•Promote tumor angiogenesis by inducing continuous release of VEGF from peripheral endothelial cells

•N1 TANs exert an antitumor activity, by direct or indirect cytotoxicity

•Suppress antitumor immunity via production of proinflammatory

•Create immunosuppressive microenvironment via production of immunosuppressive factors

•Facilitate the remodeling of local microenvironment that favors tumor cell extravasation through NETs

Tumor-associated macrophages (TAMs)

•M2 TAMs induce tumor angiogenesis by upregulating angiogenesis-associated genes such as VEGF

•M1 TAMs facilitate the recruitment and antitumor activities of cytotoxic CD8 + T cells and NK cells

•M2 TAMs facilitate the degradation of tumor extracellular matrix and the metastasis of tumor cells

•M2 TAMs activate the response of endothelial cells to growth factor signaling

•M2 TAMs upregulate TGF-β that promotes EMT

Dendritic cells (DCs)

•Induce T cell tolerance under pressure of tumor cells

•Provide initial signal for the antitumor response of CD8 + T cells

•Inhibit the proliferation and functional cytokine production of activated T cells by expressing PD-L1 and PD-L2

•Facilitate antitumor T cell response induced by immunogenic cell death

Myeloid-derived suppressor cells (MDSCs)

•Suppress antitumor immunity by producing immunosuppressive cytokines

•Promote tumor angiogenesis via VEGF and matrix metallopeptidase

•Decrease the expansion and activation of tumor-specific T cells by expressing colony-stimulating factor-1 receptor

Vascular endothelial cells

•Promote selectin-mediated rolling of tumor cells due to weakened vascular endothelial junctions upon inflammation

•Form a barrier for blood components including tumor cells to infiltrate tissues under physiological conditions