title: Small interfering RNA-mediated suppression of serum response factor, E2-promotor binding factor and survivin in non-small cell lung cancer cell lines by non-viral transfection.
abstract: OBJECTIVE
  Serum response factor (SRF), E2F1 and survivin are well-known factors involved in a multitude of cancer-related regulation processes. However, to date, no suitable means has been found to apply their potential in the therapy of non-small cell lung cancer (NSCLC). This study deals with questions of small interfering ribonucleic acid (siRNA) transfection efficiency by a non-viral transfection of NSCLC cell-lines and the power of siRNA to transiently influence cell division by specific silencing.
  
  
  METHODS
  Different NSCLC cell lines were cultured under standard conditions and transfected, with specific siRNA targeting SRF, E2F1 and survivin in a non-viral manner. Cells treated with non-specific siRNA (SCR-siRNA) served as controls. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for messenger RNA (mRNA) expression levels. Additionally, transfection efficiency was evaluated by flow cytometry. The analysis of cell proliferation was determined with a CASY cell counter 3 days after transfection with SRF or SCR-siRNA.
  
  
  RESULTS
  Transfection of the NSCLC cell lines with specific siRNAs against SRF, E2F1 and survivin resulted in a very considerable reduction of the intracellular mRNA concentration. CASY confirmation of cell viability demonstrated an excellent survival of the cell lines treated with non-specific siRNA, in contrast to with application of specific siRNA.
  
  
  CONCLUSIONS
  This study reports a reliable transfectability of NSCLC-cell lines by siRNA, initially in a non-viral manner, and a reproducible knockdown of the focussed targets, consequently leading to the death of the tumour cells. This constitutes a strong candidate for a new assessment strategy in the therapy of non-small cell lung cancer.
authors.affiliation: Department of Thoracic, Cardiac and Vascular Surgery,  Tübingen University Hospital,  Tübingen, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Walker
authors.forename: Andrea
authors.initials: A
authors.lastname: Nolte
authors.forename: Volker
authors.initials: V
authors.lastname: Steger
authors.forename: Christina
authors.initials: C
authors.lastname: Makowiecki
authors.forename: Migdat
authors.initials: M
authors.lastname: Mustafi
authors.forename: Godehard
authors.initials: G
authors.lastname: Friedel
authors.forename: Christian
authors.initials: C
authors.lastname: Schlensak
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Wendel
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D050687:E2F1 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D020868:Gene Silencing; D015316:Genetic Therapy / Q000379:methods; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000235:genetics* / Q000378:metabolism; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000235:genetics*; D026362:Serum Response Factor / Q000235:genetics* / Q000378:metabolism; D000077022:Survivin; D014162:Transfection
chemical_list: C107489:BIRC5 protein, human; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; D051034:Inhibitor of Apoptosis Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C476858:SRF protein, human; D026362:Serum Response Factor; D000077022:Survivin