Five new ent-kaurane diterpenoids,named mascaroside Ⅲ–Ⅴ(1–3),and 20-nor-cofaryloside Ⅰ–Ⅱ(4–5),together with seven known diterpenoids,were isolated from methanol extracts of the green coffee beans of Yunnan Ara...Five new ent-kaurane diterpenoids,named mascaroside Ⅲ–Ⅴ(1–3),and 20-nor-cofaryloside Ⅰ–Ⅱ(4–5),together with seven known diterpenoids,were isolated from methanol extracts of the green coffee beans of Yunnan Arabica Coffee.Their chemical structures were elucidated by extensive spectroscopic analyses.Meanwhile,cytotoxicity assay against HL-60,A-549,SMMC-7721,MCF-7 and SW480 cell lines showed that they have not evident inhibition of cytotoxicity.展开更多
Medulloblastoma(MB)is a form of malignant brain tumor that predominantly arises in infants and children,of which approximately 25%is due to upregulation of canonical Wnt pathway with mainly mutations in CTNNB1.Therefo...Medulloblastoma(MB)is a form of malignant brain tumor that predominantly arises in infants and children,of which approximately 25%is due to upregulation of canonical Wnt pathway with mainly mutations in CTNNB1.Therefore,Wnt inhibitors could offer rational therapeutic strategies and chemoprevention for this malignant cancer.In our present study,we undertook a screening for antagonists of Wnt signaling from 600 natural compounds,and identified Ginkgetin,a biflavone isolated from Cephalotaxus fortunei var.alpina.Ginkgetin inhibited Wnt pathway with an IC50 value around 5.92 lM and structure–activity relationship analysis suggested the methoxy group in Ginkgetin as a functional group.Biflavone Ginkgetin showed obvious cytotoxicity in Daoy and D283 MB cells.Cell cycle analysis by flow cytometry showed that Ginkgetin induced efficiently G2/M phase arrest in Daoy cells.Further mechanism studies showed that Ginkgetin reduced the expression of Wnt target genes,including Axin2,cyclinD1 and survivin in MB cells.The phosphorylation level of b-catenin also decreased in a time-and concentration-dependent manner.Collectively,our data suggest that Ginkgetin is a novel inhibitor of Wnt signaling,and as such warrants further exploration as a promising antimedulloblastoma candidate.展开更多
基金This work was supported financially by Programme of Key New Productions of Yunnan Province,Centre of CHINA(No.2015BB002)The STS Programme of Chinese Academy of Sciences(KFJ-SW-STS-143-8)as well as Foundation of State Key Laboratory of Phytochemistry and Plant Resources in West China(P2015-ZZ09).
文摘Five new ent-kaurane diterpenoids,named mascaroside Ⅲ–Ⅴ(1–3),and 20-nor-cofaryloside Ⅰ–Ⅱ(4–5),together with seven known diterpenoids,were isolated from methanol extracts of the green coffee beans of Yunnan Arabica Coffee.Their chemical structures were elucidated by extensive spectroscopic analyses.Meanwhile,cytotoxicity assay against HL-60,A-549,SMMC-7721,MCF-7 and SW480 cell lines showed that they have not evident inhibition of cytotoxicity.
基金the hundreds top talents program from Chinese Academy of Sciences,the NSFC(Nos.81173076,81403050)the projects of science and technology of Yunnan Province(2009C1120,2013FA047).
文摘Medulloblastoma(MB)is a form of malignant brain tumor that predominantly arises in infants and children,of which approximately 25%is due to upregulation of canonical Wnt pathway with mainly mutations in CTNNB1.Therefore,Wnt inhibitors could offer rational therapeutic strategies and chemoprevention for this malignant cancer.In our present study,we undertook a screening for antagonists of Wnt signaling from 600 natural compounds,and identified Ginkgetin,a biflavone isolated from Cephalotaxus fortunei var.alpina.Ginkgetin inhibited Wnt pathway with an IC50 value around 5.92 lM and structure–activity relationship analysis suggested the methoxy group in Ginkgetin as a functional group.Biflavone Ginkgetin showed obvious cytotoxicity in Daoy and D283 MB cells.Cell cycle analysis by flow cytometry showed that Ginkgetin induced efficiently G2/M phase arrest in Daoy cells.Further mechanism studies showed that Ginkgetin reduced the expression of Wnt target genes,including Axin2,cyclinD1 and survivin in MB cells.The phosphorylation level of b-catenin also decreased in a time-and concentration-dependent manner.Collectively,our data suggest that Ginkgetin is a novel inhibitor of Wnt signaling,and as such warrants further exploration as a promising antimedulloblastoma candidate.
