title: Dendrobium candidum inhibits MCF-7 cells proliferation by inducing cell cycle arrest at G2/M phase and regulating key biomarkers.
abstract: BACKGROUND
  Breast cancer is one of the most frequently occurring cancers in women. In recent years, Dendrobium candidum has played a part in antihyperthyroidism and anticancer drugs. This study aims to examine the antitumor effect of D. candidum on breast cancer.
  
  
  METHODS
  Human breast cancer cell line MCF-7 and normal breast epithelial cell line MCF10A were used to observe the effects of D. candidum treatment on human breast cancer. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was employed to examine the cell proliferation of the MCF-7 and MCF10A cells. Western blot analysis and reverse transcription polymerase chain reaction were used to detect the key molecules and biomarkers in breast cancer pathology. Cell cycle was analyzed by using Becton Dickinson FACScan cytofluorometer.
  
  
  RESULTS
  The results indicated that D. candidum significantly decreased cell viability at different concentrations compared to the control group (P<0.05). D. candidum-treated MCF-7 cells in the G2/M phase was significantly increased compared to the control group (P<0.05). The messenger RNA levels of estrogen receptor alpha, IGFBP2, IGFBP4, and GATA3 were significantly decreased, and the messenger RNA and protein levels of ELF5, p53, p21, p18, CDH1, CDH2, and p12 were significantly increased, compared to the control group (P<0.05). The protein levels of estrogen receptor alpha, PGR, GATA3, and Ki67 were significantly decreased and the protein levels of p53 and ELF5 were significantly increased compared to the control group (P<0.05). The general apoptosis biomarker, Bcl-2, was significantly decreased and the Bax was significantly increased compared to the control group (P<0.05). In contrast to that in MCF-7, D. candidum does not affect cell proliferation at any concentration and any time points in normal breast epithelial cells, MCF10A cells.
  
  
  CONCLUSIONS
  D. candidum could decrease the cell viability of MCF-7 cells by inducing cell cycle arrest at the G2/M phase and regulating the key biomarkers in breast cancer cells.
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Yidi
authors.initials: Y
authors.lastname: Guo
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China; Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, Changchun, People's Republic of China; National Engineering Laboratory of AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Xueqi
authors.initials: X
authors.lastname: Fu
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Yongsen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Liu
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Huo
authors.affiliation: Yunnan Research Centre for Advance Tea Processing, Yunnan Agricultural University, Kunming, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Sheng
authors.affiliation: School of Life Sciences, Jilin University, Changchun, People's Republic of China; Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, Changchun, People's Republic of China; National Engineering Laboratory of AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Hu
keywords: D. candidum; biomarker; breast cancer; inhibition; proliferation