title: [Effects of artificial microRNA targeting glucosylceramide synthase on drug sensitivity of breast cancer cells].
abstract: OBJECTIVE
  To explore the inhibitory effects on glucosylceramide synthase (GCS) expression and drug sensitivity in breast cancer cells by transfecting artificial microRNA targeting GCS.
  
  
  METHODS
  Two microRNA expression vectors targeting GCS were constructed and transfected into MCF-7/ADR cells via Lipofectamine 2000. The levels of GCS mRNA and protein were measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot respectively. Methyl thiazolyl tetrazolium (MTT) assay was used to assess the chemosensitivity of MCF-7/ADR cells to adriamycin (ADM) and vincristine.
  
  
  RESULTS
  After transfection of two microRNA expression vectors, the expression of GCSmRNA in MCF-7/ADR cells was 0.098 ± 0.005 and 0.143 ± 0.007 respectively. Compared with the control cells (0.875 ± 0.008), the difference was significant (P < 0.01). The expression of GCS protein (0.127 ± 0.004, 0.165 ± 0.008) in MCF-7/ADR cells was lower than that in the control cells (0.765 ± 0.007; P < 0.01). Furthermore, in comparison with the control cells, the resistance factor to adriamycin significantly dropped to 4.06 and 6.06 while the drug resistance to vincristine decreased to 8.30 and 12.67 respectively (P < 0.01).
  
  
  CONCLUSIONS
  Artificial microRNA targeting GCS inhibits the GCS expression and restores significantly the sensitivity of breast cancer cells to anticancer drugs. These findings may provide a novel strategy of enhancing the chemotherapy sensitivity of breast cancer.
authors: Department of Pathology, School of Medicine, Shandong University, Jinan 250012, China.
authors: Yan-lin
authors: YL
authors: Sun
authors: Peng
authors: P
authors: Gao
authors: Xiao-fang
authors: XF
authors: Zhang
authors: Yong-sheng
authors: YS
authors: Gao
authors: Geng-yin
authors: GY
authors: Zhou
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics*; D016503:Drug Delivery Systems; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D005260:Female; D005964:Glucosyltransferases / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D061986:MCF-7 Cells; D035683:MicroRNAs / Q000235:genetics / Q000627:therapeutic use; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D035683:MicroRNAs; D012333:RNA, Messenger; D005964:Glucosyltransferases; C023246:ceramide glucosyltransferase