title: Corn silk maysin induces apoptotic cell death in PC-3 prostate cancer cells via mitochondria-dependent pathway.
abstract: OBJECTIVE
  Despite recent advances in prostate cancer diagnostics and therapeutics, the overall survival rate still remains low. This study was aimed to assess potential anti-cancer activity of maysin, a major flavonoid of corn silk (CS, Zea mays L.), in androgen-independent human prostate cancer cells (PC-3).
  
  
  METHODS
  Maysin was isolated from CS of Kwangpyeongok, a Korean hybrid corn, via methanol extraction and preparative C18 reverse phase column chromatography. Maysin cytotoxicity was determined by either monitoring cell viability in various cancer cell lines by MTT assay or morphological changes. Apoptotic cell death was assessed by annexin V-FITC/PI double staining, depolarization of mitochondrial membrane potential (MMP), expression levels of Bcl-2 and pro-caspase-3 and by terminal transferase mediated dUTP-fluorescein nick end labeling (TUNEL) staining. Underlying mechanism in maysin-induced apoptosis of PC-3 cells was explored by evaluating its effects on Akt and ERK pathway.
  
  
  RESULTS
  Maysin dose-dependently reduced the PC-3 cell viability, with an 87% reduction at 200 μg/ml. Maysin treatment significantly induced apoptotic cell death, DNA fragmentation, depolarization of MMP, and reduction in Bcl-2 and pro-caspase-3 expression levels. Maysin also significantly attenuated phosphorylation of Akt and ERK. A combined treatment with maysin and other known anti-cancer agents, including 5-FU, etoposide, cisplatin, or camptothecin, synergistically enhanced PC-3 cell death.
  
  
  CONCLUSIONS
  These results suggested for the first time that maysin inhibits the PC-3 cancer cell growth via stimulation of mitochondria-dependent apoptotic cell death and may have a strong therapeutic potential for the treatment of either chemo-resistant or androgen-independent human prostate cancer.
authors.affiliation: Department of Biotechnology, The CUK Agromedical Research Center, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea.
authors.forename: Jisun
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Biotechnology, The CUK Agromedical Research Center, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea.
authors.forename: Seul
authors.initials: S
authors.lastname: Lee
authors.affiliation: National Institute of Crop Science, RDA, Suwon, Gyeonggi-do 441-857, Republic of Korea.
authors.forename: Sun-Lim
authors.initials: SL
authors.lastname: Kim
authors.affiliation: Department of Biotechnology, The CUK Agromedical Research Center, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Choi
authors.affiliation: Department of Biotechnology, The CUK Agromedical Research Center, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea.
authors.forename: Jeong Yeon
authors.initials: JY
authors.lastname: Seo
authors.affiliation: Department of Biotechnology, The CUK Agromedical Research Center, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea.
authors.forename: Doo Jin
authors.initials: DJ
authors.lastname: Choi
authors.affiliation: Department of Biotechnology, The CUK Agromedical Research Center, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea. Electronic address: yongil382@catholic.ac.kr.
authors.forename: Yong Il
authors.initials: YI
authors.lastname: Park
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D011467:Prostate / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D005419:Flavonoids; D005960:Glucosides; C114429:maysin; D051057:Proto-Oncogene Proteins c-akt; D053148:Caspase 3
keywords: Anti-cancer; Apoptosis; Corn silk; Maysin; Prostate cancer