title: Particled Mica, STB-HO has chemopreventive potential via G1 arrest, and inhibition of proliferation and vascular endothelial growth factor receptor 2 in HCT colorectal cancer cells.
abstract: BACKGROUND
  Though Mica, a thin and sheet like mineral, has been used as a mineral medicine for treatment of bleeding, dysentery and inflammation in traditional medicine including Ayurveda, the biological evidences of Mica were not clearly elucidated so far. Thus, in the present study, the antitumor mechanism of particled Mica (STB-HO) was examined in colorectal cancers.
  
  
  METHODS
  Athymic nude mice were inoculated with HCT116 colon cancer cells and orally administered STB-HO daily for 41 days, and HCT116 and human umbilical vein endothelial cells (HUVECs) were treated with STB-HO for 0 ~ 24 hours to perform immunoblotting, cytotoxicity assay, FACs analysis and measurement of matrix metalloproteinase 9 (MMP-9) secretion and other experiments. Significant differences of all date were evaluated using Student's t-test and a Turkey-Kramer multiple-comparison post test.
  
  
  RESULTS
  STB-HO significantly suppressed the tumor volume and weight in athymic nude mice inoculated with HCT116 cells at a dose of 100 mg/kg. Thus, the in vivo antitumor mechanism of STB-HO was to elucidated in vitro as well. STB-HO exerted cytotoxicity in HCT116, SW620 and HCT15 colorectal cancer cells. Also, STB-HO increased G1 cell population in a time and concentration dependent manner, enhanced the expression of p21, p27, p53 as cyclin dependent kinase (CDK) inhibitors, attenuated the expression of proliferating cell nuclear antigen (PCNA) and cyclin D1 and also reduced the production of vascular endothelial growth factor (VEGF) and matrix metalloproteinase 9 (MMP-9) in HCT116 cells. Consistently, STB-HO suppressed the phosphorylation of VEGFR2 in HCT116, SW620 and HCT15 cells. Also, STB-HO inhibited the VEGF mediated proliferation and also attenuated the phosphorylation of VEGFR2 and Akt in human umbilical vein endothelial cells (HUVECs).
  
  
  CONCLUSIONS
  Collectively, these findings suggest that STB-HO has chemopreventive potential via G1 arrest and inhibition of proliferation and VEGFR2 in HCT116 colorectal cancer cells.
authors.forename: Sung-Yun
authors.initials: SY
authors.lastname: Cho
authors.forename: Hyo-Jeong
authors.initials: HJ
authors.lastname: Lee
authors.forename: Sun-Mi
authors.initials: SM
authors.lastname: Cho
authors.forename: Bonglee
authors.initials: B
authors.lastname: Kim
authors.forename: Yeon Kwon
authors.initials: YK
authors.lastname: Jung
authors.forename: Sung-Hoon
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000538:Aluminum Silicates / Q000494:pharmacology* / Q000627:therapeutic use*; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D049109:Cell Proliferation; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D005260:Female; D059585:G1 Phase Cell Cycle Checkpoints / Q000187:drug effects*; D045325:HCT116 Cells; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D014471:Umbilical Veins; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism*
chemical_list: D000538:Aluminum Silicates; D000970:Antineoplastic Agents; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2; D051057:Proto-Oncogene Proteins c-akt; C011934:mica