title: [Effects of chrysin on sphere formation and CK2α expression of ovarian cancer stem-like cells derived from SKOV3 cell line].
abstract: OBJECTIVE
  To investigate whether inhibitory effect of chrysin on sphere formation of ovarian cancer stem-like cells(spheroids derived from human ovarian cancer SKOV3 cell line ) is involved in the down-regulating of the protein expression of casein kinase CK2α.
  
  
  METHODS
  SKOV3-derived ovarian cancer stem-like cells obtained by suspension culture in stem cell-condition medium using ultra-low adhesion plate were treated with various concentrations (5.0, 10.0 and 20.0 μmol/L) of chrysin. Sphere formation assay was used to determine the sphere forming rate of SKOV3-derived ovarian cancer stem-like cells. Western blot was used to analyze the protein expressions of CK2α and cancer stem cell markers CD133 and CD44. Silence of CK2α by siRNA and ectopic expression of CK2α by transfection with pcDNA3.1-CK2α plasmid were used to explore the mechanism underlying the effect of chrysin on sphere formation of SKOV3-derived ovarian cancer stem-like cells.
  
  
  RESULTS
  Chrysin (5.0, 10.0 and 20.0 μmol/L) significantly reduced the sphere forming rate of SKOV3-derived ovarian cancer stem-like cells, in a concentration-dependent manner (22.3%±2.5% vs 14.7%±2.1%, 8.6%± 1.7% and 3.8% ± 1.1% respectively; P<0.05). In addition, chrysin (5.0, 10.0 and 20.0 μmol/L) obviously down-regulated the protein expressions of CK2α, CD133 and CD44 in SKOV3-derived ovarian cancer stem-like cells. In combination with CK2α siRNA transfection and chrysin synergistically decreased sphere formation (P<0.05) and the protein expressions of CK2α, CD133 and CD44 in SKOV3-derived ovarian cancer stem-like cells. However, transfection with pcDNA3.1-CK2α plasmid attenuated inhibitory effects of chrysin on sphere formation capability and the expressions of CK2α, CD133 and CD44 of SKOV3-derived ovarian cancer stem-like cells.
  
  
  CONCLUSIONS
  Down-regulation of CK2α protein expression is involved in the inhibition effect of chrysin on the sphere formation capability of SKOV3-derived ovarian cancer stem-like cells.
authors.affiliation: Department of Obstetrics and Gynecology, the Fourth Affiliated Hospital of Guangzhou Medical University, Guangzhou 511447, China.
authors.forename: H Z
authors.initials: HZ
authors.lastname: Li
authors.forename: Y H
authors.initials: YH
authors.lastname: Chen
authors.forename: Y L
authors.initials: YL
authors.lastname: Fang
authors.forename: L Y
authors.initials: LY
authors.lastname: Zhong
authors.forename: Q Q
authors.initials: QQ
authors.lastname: Yuan
authors.forename: X Y
authors.initials: XY
authors.lastname: Xu
authors.forename: J G
authors.initials: JG
authors.lastname: Cao
mesh_terms: D047390:Casein Kinase II; D045744:Cell Line, Tumor; D015536:Down-Regulation; D005260:Female; D005419:Flavonoids; D006801:Humans; D018960:Hyaluronan Receptors; D014411:Neoplastic Stem Cells; D010051:Ovarian Neoplasms; D034741:RNA, Small Interfering; D014162:Transfection
chemical_list: C497483:CD44 protein, human; D005419:Flavonoids; D018960:Hyaluronan Receptors; D034741:RNA, Small Interfering; C043561:chrysin; C570325:CSNK2A1 protein, human; D047390:Casein Kinase II