Table 1.

Polysaccharides with antitumor potential, the main route of action, and considerations on the mechanisms of activity.

Source / name of the polysaccharide	Mechanism	Activity / cell line / animal model	Structure/ molecular weight (Wb)	Concluding remarks	References
Lentinus giganteus (LGPS)	Depolarization of the mitochondrial membrane	Cell viability.		The polysaccharide increased the proportion of Ba / Bcl-2, promoted the release of cytochrome c in the cytoplasm, in addition to inhibiting Akt phosphorylation in HepG2 cells, inducing intrinsic mitochondrial apoptosis and PI3K / Akt signaling pathways.	(Tian, Zhao, Zeng, Zhang, & Zheng, 2016)
		Cell line: HepG2.	Wb: 1.547 × 105 Da
Armillaria mellea (AMP)	Depolarization of the mitochondrial membrane	Caspase 3 (c3) and caspase 9 (c9) activity after 2 h.	Glucan	The polysaccharide induced an interruption of the cell cycle in the G0 / G1 phase, accompanied by an increase in apoptotic cells. It induced interruption of the mitochondrial membrane potential, leading to the release of cytochrome c by mitochondria and activation of caspase-3 and -9.	(Wu et al., 2012)
		Cell line: A549.	Wb: 4.6 × 105 Da
Trametes robiniophila (TRP)	Depolarization of the mitochondrial membrane	-Cell line: Human osteosarcoma cell (U-2 OS).	1,3,6- and 1,4-linked glucpyranosyl moieties, with 1-linked arabinofuranosyl and galactopyranosyl terminal at the O-3 position of 1,3,6-linked glucpyranosyl residues-	The polysaccharide increased the levels of the pro-apoptotic Bax protein and decreased the level of the anti-apoptotic Bcl-2 protein, increasing the Bax / Bcl-2 ratio and protein expression of caspase-9, caspase-3, and PARP.	(Zhao, Ma, Liu, Liu, & Wang, 2015)
Hirsutella sinensis (HSP-III)	Depolarization of the mitochondrial membrane	Cellular apoptosis.	skeleton linked to β-glucan containing (1 → 3) and occasionally branched	The polysaccharide has a high molecular weight and significantly inhibited lung cancer growth. The apoptotic effects of HSP-III are triggered by the generation of reactive oxygen species (ROS).	(Liu, Xie, Sun, Meng, & Zhu, 2017)
		Cell line: lung cancer.	Wb: 513.89 kDa
Trametes robiniophil (W-NTRP)	Nitric oxide pathway	-Cell line: QBC939, Sk-ChA-1 and MZ-ChA-1.	Heteropolysaccharide.Galactose, arabinose, glucose. Relative molar ratio of 4.2: 2.5: 0.7	The polysaccharide activates macrophages and induces the production of nitric oxide (NO) through the positive regulation of the inducible activity of NO synthase (iNOS). In the three models evaluated, the polysaccharide showed a remarkable inhibitory effect against human cholangiocarcinoma cell lines.	(Sun et al., 2013)
			Wb: 2.5 × 104 Da
Pleurotus ostreatus (WPOP-N1)	Nitric oxide pathway	–	–	The polysaccharide significantly inhibited tumor growth in mice bearing Sarcoma 180 tumor and markedly increased the level of TNF-α secretion in the serum, and increased NO secretion.	(Kong et al., 2014)
Trametes orientalis (TOP-2)	Immunomodulation	Serum levels of cytokine. Animal model: mice. Cell line: lung carcinoma.	Heteropolysaccharide. Galactose, glucose, mannose, and arabinose. Molar ratios of 5.79: 5.77: 3.45: 1	The polysaccharide considerably increased the proliferation of splenocytes, significantly stimulated the phagocytotic function of macrophages, and markedly promoted the expression of serum cytokines.	(Zheng, Wang, & Li, 2015)
			Wb: 63 kDa
Boletus edulis (BEP)	Immunomodulation	TNF-α levels Animal model: mice. Cell line: kidney cancer.	Consisting of (1→6)-linked-α-d-glucopyranosyl, (1→2,6)-linked-α-d-galactopyranosyl, (1→6)-linked-α-d-galactopyranosyl, and (1→3)-linked-α-d-rhamnopyranosyl residues, which were branched at O-2 position of (1→2,6)-linked-α-d-galactopyranosyl residue with a single terminal (1→)-linked-α-l-arabinofuranosyl residue.	The polysaccharide significantly increased the spleen and thymus indices, increased the proliferation of splenocytes, the activities of NK and CTL cells in the spleen, and promoted the secretion of cytokines IL-2 and TNF-α in mice with Renca tumor.	(Wang, Sun, Wu, Yang, & Tan, 2014)
			Wb: 113.432 Da