title: A chrysin derivative suppresses skin cancer growth by inhibiting cyclin-dependent kinases.
abstract: Chrysin (5,7-dihydroxyflavone), a natural flavonoid widely distributed in plants, reportedly has chemopreventive properties against various cancers. However, the anticancer activity of chrysin observed in in vivo studies has been disappointing. Here, we report that a chrysin derivative, referred to as compound 69407, more strongly inhibited EGF-induced neoplastic transformation of JB6 P(+) cells compared with chrysin. It attenuated cell cycle progression of EGF-stimulated cells at the G1 phase and inhibited the G1/S transition. It caused loss of retinoblastoma phosphorylation at both Ser-795 and Ser-807/811, the preferred sites phosphorylated by Cdk4/6 and Cdk2, respectively. It also suppressed anchorage-dependent and -independent growth of A431 human epidermoid carcinoma cells. Compound 69407 reduced tumor growth in the A431 mouse xenograft model and retinoblastoma phosphorylation at Ser-795 and Ser-807/811. Immunoprecipitation kinase assay results showed that compound 69407 attenuated endogenous Cdk4 and Cdk2 kinase activities in EGF-stimulated JB6 P(+) cells. Pulldown and in vitro kinase assay results indicated that compound 69407 directly binds with Cdk2 and Cdk4 in an ATP-independent manner and inhibited their kinase activities. A binding model between compound 69407 and a crystal structure of Cdk2 predicted that compound 69407 was located inside the Cdk2 allosteric binding site. The binding was further verified by a point mutation binding assay. Overall results indicated that compound 69407 is an ATP-noncompetitive cyclin-dependent kinase inhibitor with anti-tumor effects, which acts by binding inside the Cdk2 allosteric pocket. This study provides new insights for creating a general pharmacophore model to design and develop novel ATP-noncompetitive agents with chemopreventive or chemotherapeutic potency.
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea,; the Hormel Institute, University of Minnesota, Austin, Minnesota 55912,; the Department of Cardiothoracic Surgery and; Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital, Central South University, Renmin Road 139, Changsha, Hunan 410011, China.
authors.forename: Haidan
authors.initials: H
authors.lastname: Liu
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea,; the Hormel Institute, University of Minnesota, Austin, Minnesota 55912,; the Basic Medical College, Zhengzhou University, ZhengZhou 450001 China, and.
authors.forename: Kangdong
authors.initials: K
authors.lastname: Liu
authors.affiliation: the Hormel Institute, University of Minnesota, Austin, Minnesota 55912.
authors.forename: Zunnan
authors.initials: Z
authors.lastname: Huang
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea.
authors.forename: Chan-Mi
authors.initials: CM
authors.lastname: Park
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea.
authors.forename: N R
authors.initials: NR
authors.lastname: Thimmegowda
authors.affiliation: the Chemical Biology Research Center, Korea Research Institute of Bioscience and Biotechnology, Yangcheng-ri, Ochang, Cheongwon, Chungcheongbuk-do 363-883, Republic of Korea.
authors.forename: Jae-Hyuk
authors.initials: JH
authors.lastname: Jang
authors.affiliation: the Chemical Biology Research Center, Korea Research Institute of Bioscience and Biotechnology, Yangcheng-ri, Ochang, Cheongwon, Chungcheongbuk-do 363-883, Republic of Korea.
authors.forename: In-Ja
authors.initials: IJ
authors.lastname: Ryoo
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea.
authors.forename: Long
authors.initials: L
authors.lastname: He
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea.
authors.forename: Sun-Ok
authors.initials: SO
authors.lastname: Kim
authors.affiliation: the Hormel Institute, University of Minnesota, Austin, Minnesota 55912.
authors.forename: Naomi
authors.initials: N
authors.lastname: Oi
authors.affiliation: the Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Ki Won
authors.initials: KW
authors.lastname: Lee
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea.
authors.forename: Nak-Kyun
authors.initials: NK
authors.lastname: Soung
authors.affiliation: the Hormel Institute, University of Minnesota, Austin, Minnesota 55912.
authors.forename: Ann M
authors.initials: AM
authors.lastname: Bode
authors.affiliation: the Department of Cardiothoracic Surgery and.
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Yang
authors.affiliation: the Department of Cardiothoracic Surgery and.
authors.forename: Xinmin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: the Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138.
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Erikson
authors.affiliation: the Chemical Biology Research Center, Korea Research Institute of Bioscience and Biotechnology, Yangcheng-ri, Ochang, Cheongwon, Chungcheongbuk-do 363-883, Republic of Korea.
authors.forename: Jong-Seog
authors.initials: JS
authors.lastname: Ahn
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea.
authors.forename: Joonsung
authors.initials: J
authors.lastname: Hwang
authors.affiliation: the Department of Biochemistry, College of Natural Science, Chung Nam National University, Yuseong, Daejeon 305-764, Republic of Korea.
authors.forename: Kyoon Eon
authors.initials: KE
authors.lastname: Kim
authors.affiliation: the Hormel Institute, University of Minnesota, Austin, Minnesota 55912,. Electronic address: zgdong@hi.umn.edu.
authors.forename: Zigang
authors.initials: Z
authors.lastname: Dong
authors.affiliation: From the World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon 363-883, Republic of Korea,. Electronic address: zgdong@hi.umn.edu.
authors.forename: Bo-Yeon
authors.initials: BY
authors.lastname: Kim
mesh_terms: D000494:Allosteric Regulation / Q000187:drug effects; D000818:Animals; D001665:Binding Sites; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D018360:Crystallography, X-Ray; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology*; D016193:G1 Phase / Q000187:drug effects / Q000235:genetics; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008958:Models, Molecular; D009368:Neoplasm Transplantation; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D016160:Retinoblastoma Protein / Q000235:genetics / Q000378:metabolism; D016196:S Phase / Q000187:drug effects / Q000235:genetics; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics / Q000473:pathology
chemical_list: D005419:Flavonoids; D047428:Protein Kinase Inhibitors; D016160:Retinoblastoma Protein; C043561:chrysin; D004815:Epidermal Growth Factor; D018844:Cyclin-Dependent Kinases
keywords: ATP; ATP-noncompetitive; CDK (Cyclin-dependent Kinase); CDK Inhibitor; Cell Cycle; Chemoprevention; Chrysin Derivative; Epidermal Growth Factor (EGF); Natural Compound