title: In vitro antitumor activity of stellettin B, a triterpene from marine sponge Jaspis stellifera, on human glioblastoma cancer SF295 cells.
abstract: Stellettin B was isolated from marine sponge Jaspis stellifera. In vitro antitumor activities were investigated on 39 human cancer cell lines. Stellettin B exhibited highly potent inhibition against the growth of a human glioblastoma cell line SF295, with a GI50 of 0.01 μM. In contrast, stellettin B showed very weak inhibitory activity on normal cell lines including HMEC, RPTEC, NHBE and PrEC, with GI50s higher than 10 μM, suggesting its relatively selective cytotoxicity against human cancer cells compared to normal human cell lines. We then focused on the antitumor activity of this compound on SF295 cells. Flow cytometric analysis indicated that stellettin B induced apoptosis in SF295 cells in a concentration-dependent manner. Further study indicated that stellettin B increased the production of ROS, the activity of caspase 3/7, as well as the cleavage of PARP, each of which is known to be involved in apoptosis. To investigate the molecular mechanism for cell proliferation inhibition and apoptosis induction, effect on the phosphorylation of several signal proteins of PI3K/Akt and RAS/MAPK pathways was examined. Stellettin B inhibited the phosphorylation of Akt potently, with no activity on p-ERK and p-p38, suggesting that inhibition of PI3K/Akt pathway might be involved in the antiproliferative and apoptosis-inducing effect. However, homogenous time-resolved fluorescence (HTRF) assay indicated that stellettin B did not inhibit PI3K activity, suggesting that the direct target might be signal protein upstream of Akt pathway other than PI3K.
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences and Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China. tangshengan@tijmu.edu.cn.
authors.forename: Sheng-An
authors.initials: SA
authors.lastname: Tang
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences and Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China. zqx9260@163.com.
authors.forename: Qianxiang
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Division of Molecular Pharmacology, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31, Ariake, Koto-ku, Tokyo 135-8550, Japan. guo.wenzhi@jfcr.or.jp.
authors.forename: Wen-Zhi
authors.initials: WZ
authors.lastname: Guo
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences and Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China. qiuyuling@tijmu.edu.cn.
authors.forename: Yuling
authors.initials: Y
authors.lastname: Qiu
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences and Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China. wangran@tijmu.edu.cn.
authors.forename: Ran
authors.initials: R
authors.lastname: Wang
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences and Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China. jinmeihua@tijmu.edu.cn.
authors.forename: Meihua
authors.initials: M
authors.lastname: Jin
authors.affiliation: School of Chemistry, Shandong University, 27 Shanda South RD, Jinan 250100, China. 68875299@163.com.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Obstetrics and Gynecology, Tianjin University Hospital, Tianjin 300072, China. likeleaf77@gmail.com.
authors.forename: Ke
authors.initials: K
authors.lastname: Li
authors.affiliation: Division of Molecular Pharmacology, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31, Ariake, Koto-ku, Tokyo 135-8550, Japan. yamorit@jfcr.or.jp.
authors.forename: Takao
authors.initials: T
authors.lastname: Yamori
authors.affiliation: Division of Molecular Pharmacology, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31, Ariake, Koto-ku, Tokyo 135-8550, Japan. sdan@jfcr.or.jp.
authors.forename: Shingo
authors.initials: S
authors.lastname: Dan
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences and Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China. kongdexin@tijmu.edu.cn.
authors.forename: Dexin
authors.initials: D
authors.lastname: Kong
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000473:pathology; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005909:Glioblastoma / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011161:Porifera / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D014315:Triterpenes / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D017382:Reactive Oxygen Species; D014315:Triterpenes; C452212:stellettin B; D011065:Poly(ADP-ribose) Polymerases; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D053148:Caspase 3; D053179:Caspase 7