Table 1.

Representative natural products with immuno-tumor therapeutic effects.

Category	Natural product	Source	Mechanism
Polysaccharides	Ascophyllan	Ascophyllum nodosum	Increasing MHC I, MHC II and pro-inflammatory levels of cytokines; ultimately inducing activation of DCs and antigen-specific immune responses
	Ganodema polysaccharides	Ganodema	Down-regulate the expression of PD-1 and PD-L1 through STAT3 pathway
	CMPB90-1	Cordyceps militaris	Down-regulate the expression of PD-L1 through NF-kB pathway
	Fucoidan	Ascophyllum nodosum	Promotes the growth of human peripheral blood DC
Alkaloids	Chloroquine	Cinchona bar	Increasing the lysosomal pH of TAM, mediating Ca2+ release and activating TFEB
	Tryptanthrin-5c	Polygonum tinctorium and Isatis tinctoria	nhibits the activity of IDO and treg accumulation
	5-Br-brassinin	Cruciferous sp.	Inhibiting the activity of IDO1 and mediating tumor regression when combined with chemotherapeutic drugs in MMTV-Neu mice
Saponins	QS-21	Quillaja saponaria Molin	Enhance the anti-cancer effect of cancer vaccines
	Sapogenin	Panax ginseng	Down-regulation of PD-1 and PD-L1 expression through the STAT3 pathway
	Diosgenin	Acacia concinna	Enhancing the anti-cancer effects of anti-PD-1 antibodies
Flavonoids	Hesperidin	Orange peel	Downregulation of PD-L1 expression via NF-kB pathway
	Baicalein	Scutellaria	Downregulation of PD-L1 expression via JAKSTAT pathway
	Procyanidin	Fruits	Enhancing the anti-cancer effects of cancer peptide vaccines
Terpenoids	Artemisinin	Artemisia annua	Inhibiting the proliferation of MDSCs and Tregs, and promoting the proliferation of CD4 + T and CD8 + T cells
	Ginsenoside Rk1	Black ginseng	Downregulation of PD-L1 by inhibiting NF-κB signaling
	Ingenol-3,20-dibenzoate	Euphorbia esula L	Activating PKC, promoting IFN-γ secretion and degranulation, and ultimately increasing NK cell cytotoxicity