Fig. 3
From: Rise of the natural red pigment ‘prodigiosin’ as an immunomodulator in cancer
A proposed model for the immunomodulatory effect of prodigiosin on TAM-mediated immunosuppression via ROS imbalance and inhibition of MMP-9, PGE-2, VEGF, TNF-α, PI3K/Akt, LPS, IFN-γ, cytokines, and chemokines. CTCs, circulating tumour cells; IFN-γ, interferon-gamma; LPS, lipopolysaccharide; MMP-9, matrix metalloproteinase-9; PD-L1, programmed death-ligand 1; PGE-2, prostaglandin E2; PI3K/Akt, phosphoinositide-3-kinase–protein kinase/Akt; ROS, reactive oxygen species; TAM, tumour-associated macrophages; TNF-α, tumour necrosis factor-alpha; VEGF, vascular endothelial growth factor