title: Human mesenchymal stem cells promote growth of osteosarcoma: involvement of interleukin-6 in the interaction between human mesenchymal stem cells and Saos-2.
abstract: Our previous study showed that exogenous human mesenchymal stem cells (hMSCs) targeted established osteosarcoma and promoted its growth and pulmonary metastasis in vivo. As a follow-up, the present study aimed to investigate how hMSCs would interact with Saos-2 through autocrine/paracrine communication. The results showed that co-injection of hMSCs with Saos-2 into the proximal tibia of nude mice could promote tumor growth and progression. In vitro, the proliferation of Saos-2 and hMSCs was promoted by each other's conditioned medium, in which interleukin-6 (IL-6) played an important role. Osteogenic differentiation of hMSCs could be inhibited by conditioned medium of Saos-2, in which IL-6 was also involved. Furthermore, decreased IL-6 secretion by hMSCs during its osteogenesis and increased IL-6 secretion in response to conditioned medium of Saos-2 were observed. Based on these data, we suggest that there was a positive feedback loop of IL-6 in the interaction between hMSCs and Saos-2.
authors.affiliation: Shanghai Key Laboratory of Orthopaedic Implant, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Bian
authors.forename: Qi-Ming
authors.initials: QM
authors.lastname: Fan
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.forename: Wen-Ting
authors.initials: WT
authors.lastname: Xu
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Tang
mesh_terms: D000818:Animals; D001859:Bone Neoplasms / Q000378:metabolism* / Q000473:pathology; D002450:Cell Communication / Q000502:physiology*; D002454:Cell Differentiation / Q000502:physiology; D045744:Cell Line, Tumor; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D012516:Osteosarcoma / Q000378:metabolism* / Q000473:pathology; D034741:RNA, Small Interfering / Q000235:genetics; D023041:Xenograft Model Antitumor Assays
chemical_list: D015850:Interleukin-6; D034741:RNA, Small Interfering