title: [Effects of RNA interference and nolatrexed on thymidylate synthase expression and cell proliferation of human colorectal carcinoma LOVO cells].
abstract: OBJECTIVE
  To investigate the effect of the RNAi and the chemotherapy drugs nolatrxed on the expression of thymidylate synthase(TS) and the growth of the colorectal carcinoma LOVO cells.
  
  
  METHODS
  The siRNA was constructed targeting the human TS gene, and then transfected into the human colorectal cancer LOVO cells. RT-PCR and Western blot technique were used to observe the TS gene and protein expression levels, and MTT was used to detect cell proliferation after silencing the TS gene. In addition, siRNA and nolatrxed were applied to the LOVO cells to observe the TS protein expression and cell growth.
  
  
  RESULTS
  TS siRNA significantly reduced the expression of TS gene and protein in LOVO cells, and inhibited cell growth. The IC50 value of LOVO cells was (1.46±0.25) μmol/L in TS siRNA combined with nolatrexed group, (6.81±0.31) μmol/L in the negative control group, and (6.47±0.43) μmol/L in the single nolatrexed group. After treatment of TS siRNA combined with nolatrexed on LOVO cells for 36 hours, the apoptosis index was higher than that in single TS siRNA and nolatrexed[(62.12±0.89)% vs.(21.56±0.67)% and(40.51±0.83)%, both P<0.05].
  
  
  CONCLUSIONS
  TS siRNA can partly suppress the expression of TS gene in LOVO cells, inhibit cell proliferation, promote cell apoptosis and enhance cell sensitivity to apoptosis induced by nolatrexd.
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital, Shandong University, Jinan 250021, China.
authors.forename: Shu-bo
authors.initials: SB
authors.lastname: Tian
authors.forename: Chang-qing
authors.initials: CQ
authors.lastname: Jing
authors.forename: Le-ping
authors.initials: LP
authors.lastname: Li
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D011799:Quinazolines / Q000494:pharmacology*; D034622:RNA Interference; D013940:Thymidylate Synthase / Q000235:genetics* / Q000378:metabolism
chemical_list: D011799:Quinazolines; D013940:Thymidylate Synthase; C099178:nolatrexed