title: Activation of antitumor immune responses by Ganoderma formosanum polysaccharides in tumor-bearing mice.
abstract: Fungi of the genus Ganoderma are basidiomycetes that have been used as traditional medicine in Asia and have been shown to exhibit various pharmacological activities. We recently found that PS-F2, a polysaccharide fraction purified from the submerged culture broth of Ganoderma formosanum, stimulates the maturation of dendritic cells and primes a T helper 1 (Th1)-polarized adaptive immune response in vivo. In this study, we investigated whether the immune adjuvant function of PS-F2 can stimulate antitumor immune responses in tumor-bearing mice. Continuous intraperitoneal or oral administration of PS-F2 effectively suppressed the growth of colon 26 (C26) adenocarcinoma, B16 melanoma, and sarcoma 180 (S180) tumor cells in mice without adverse effects on the animals' health. PS-F2 did not cause direct cytotoxicity on tumor cells, and it lost the antitumor effect in mice with severe combined immunodeficiency (SCID). CD4(+) T cells, CD8(+) T cells, and serum from PS-F2-treated tumor-bearing mice all exhibited antitumor activities when adoptively transferred to naïve animals, indicating that PS-F2 treatment stimulates tumor-specific cellular and humoral immune responses. These data demonstrate that continuous administration of G. formosanum polysaccharide PS-F2 can activate host immune responses against ongoing tumor growth, suggesting that PS-F2 can potentially be developed into a preventive/therapeutic agent for cancer immunotherapy.
authors.affiliation: Department of Biochemical Science and Technology, National Taiwan University, Taipei, 10617, Taiwan, Republic of China.
authors.forename: Cheng-Li
authors.initials: CL
authors.lastname: Wang
authors.forename: Chiu-Ying
authors.initials: CY
authors.lastname: Lu
authors.forename: Ying-Chao
authors.initials: YC
authors.lastname: Hsueh
authors.forename: Wen-Hsiung
authors.initials: WH
authors.lastname: Liu
authors.forename: Chun-Jen
authors.initials: CJ
authors.lastname: Chen
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D062610:Fungal Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D032902:Ganoderma / Q000378:metabolism*; D007155:Immunologic Factors / Q000302:isolation & purification / Q000494:pharmacology*; D007167:Immunotherapy / Q000379:methods*; D051379:Mice; D009369:Neoplasms / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D062610:Fungal Polysaccharides; D007155:Immunologic Factors