title: [The effect of As2O3 on induction of apoptosis and inhibition of telomerase activity in colon cancer LS-174T cells].
abstract: OBJECTIVE
  To study the impact of arsenic trioxide (As2O3) on human colorectal carcinoma LS-174T cells and their activity of telomerase.
  
  
  METHODS
  LS-174T cells and xenograft model of nude mice were treated with As2O3. The inhibitory effect of As2O3 on survival of LS-174T cells was determined by MTT assay. Apoptosis was determined by electron microscopy and fluorescence microscopy. Cell cycle was assessed by flow cytometry. Telomerase activity in LS-174T cells was determined by PCR-ELISA kit.
  
  
  RESULTS
  With the increasing concentration of As2O3, the ratio of living cells to dead cells decreased significantly, and the IC50 value was 5.23 micromol/L. Apoptosis curve appeared after 24 h and cells turned to apoptosis in a time-dependent manner. As2O3 inhibited the telomerase activity in cell extraction, obviously in a concentration-dependent and time-dependent manner. Inhibitiory effect of As2O3 on xenograft model of nude mice was observed by tumor volume and weight measurement, showing a significant difference between As2O3 and control groups (P < 0.05).
  
  
  CONCLUSIONS
  Both the experiments in vitro and in vivo showed an inhibitory effect of As2O3 on colonrectal cancer S-174T cell growth, probably by induction of apoptosis and inhibition of telomerase activity.
authors.affiliation: Department of Abdominal Surgery, The Third Hospital of Harbin Medical University, Harbin 150040, China. wxshan1208@yahoo.com.cn
authors.forename: Xi-Shan
authors.initials: XS
authors.lastname: Wang
authors.forename: Gui-Yu
authors.initials: GY
authors.lastname: Wang
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Xu
authors.forename: Kuan
authors.initials: K
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: Song-Bin
authors.initials: SB
authors.lastname: Fu
authors.forename: Jing-Shu
authors.initials: JS
authors.lastname: Geng
authors.forename: Qi-Fan
authors.initials: QF
authors.lastname: Zhang
authors.forename: Xin-Shu
authors.initials: XS
authors.lastname: Dong
authors.forename: Jia-Hong
authors.initials: JH
authors.lastname: Zhao
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D000077237:Arsenic Trioxide; D001152:Arsenicals / Q000008:administration & dosage / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003110:Colonic Neoplasms / Q000473:pathology / Q000517:prevention & control* / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D020128:Inhibitory Concentration 50; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D010087:Oxides / Q000008:administration & dosage / Q000494:pharmacology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011897:Random Allocation; D019098:Telomerase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D001152:Arsenicals; D010087:Oxides; D019098:Telomerase; D000077237:Arsenic Trioxide