title: A polysaccharide from Trametes robiniophila inhibits human osteosarcoma xenograft tumor growth in vivo.
abstract: In the present study, we isolated and purified one polysaccharide (TRP) from Trametes robiniophila, which had a backbone of 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. TRP was further evaluated for its antitumor activity against xenografted U-2 OS osteosarcoma in BALB/c nude mice together with the possible mechanism of action. We found that oral administration of TRP significantly suppressed U-2 OS tumor growth in mice via the induction of apoptosis, as evidenced by the increased number of TUNEL-positive cells in tumor tissues. Moreover, TRP administration increased the levels of the proapoptotic Bax protein and decreased the level of the antiapoptotic Bcl-2 protein, thus resulting in a rise of Bax/Bcl-2 ratio. Furthermore, the protein expression of caspase-9, caspase-3 and cleaved PARP became evident in tumor tissues from mice following TRP treatment, but caspase-8 keep unchanged. Besides, overexpression of metadherin (MTDH) was attenuated in tumor tissues of TRP-fed mice. Taken together, these findings suggest that the TRP-induced apoptosis of tumor tissues is through a mitochondria-mediated intrinsic apoptotic pathway.
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, PR China.
authors.forename: Xingkai
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, PR China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Ma
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, PR China.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, PR China.
authors.forename: Jiakun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, PR China. Electronic address: wenbowanghayida@sina.com.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000187:drug effects / Q000235:genetics; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000235:genetics; D015815:Cell Adhesion Molecules / Q000187:drug effects / Q000235:genetics; D062610:Fungal Polysaccharides / Q000737:chemistry / Q000627:therapeutic use*; D015870:Gene Expression; D064593:Heterografts / Q000187:drug effects; D006801:Humans; D008565:Membrane Proteins; D051379:Mice; D008819:Mice, Nude; D012516:Osteosarcoma / Q000188:drug therapy* / Q000235:genetics; D016601:RNA-Binding Proteins; D055454:Trametes / Q000737:chemistry*; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; D015815:Cell Adhesion Molecules; D062610:Fungal Polysaccharides; C483039:MTDH protein, human; D008565:Membrane Proteins; D016601:RNA-Binding Proteins
keywords: Apoptosis; Polysaccharide; Trametes robiniophila; U-2 OS human osteosarcoma cells; Xenograft tumor