title: Evaluation of microRNA expression in head and neck squamous cell carcinoma cell lines and in primary culture of oral keratinocytes.
abstract: OBJECTIVE
  Functional in vitro studies are fundamental to understand the role of microRNAs, small non coding RNA molecules that function as post-transcriptional regulators, in cancer. The objective of this study was to determine the applicability of head and neck squamous cell carcinoma cell lines and human oral keratinocytes as models for functional studies on microRNAs previously identified as deregulated in head and neck squamous cell carcinomas.
  
  
  METHODS
  The expression level of four microRNAs was assessed in cell lines and in primary cultures of oral keratinocytes using specific real-time polymerase chain reactions. The identity of oral squamous cell carcinoma cell lines was confirmed by means of STR (short tandem repeats) profiling. The possible impact of feeder-layer gene expression in global microRNA expression results from keratinocyte primary culture was also evaluated.
  
  
  RESULTS
  Significant differences in microRNA gene expression were observed among squamous cell carcinoma cell lines, particularly among cells lines from distinct subsites, as well as between primary culture of human keratinocytes and immortalized keratinocyte cell lines.
  
  
  CONCLUSIONS
  Primary cultures of human keratinocytes and diverse tumor cell lines are relatively easy to obtain. However, each cell model possesses a characteristic phenotype; whereas one may be useful for a specific study, it may be inappropriate for another. Therefore, it is imperative that suitable cell lines are cautiously selected for functional studies in cancer.
authors.affiliation: Centro de Pesquisa Experimental, Instituto Israelita de Ensino e Pesquisa Albert Einstein - IIEPAE, São Paulo, SP, BR.
authors.forename: Flavia Maziero
authors.initials: FM
authors.lastname: Andreghetto
authors.affiliation: Centro de Tecnologia das Radiações, Instituto de Pesquisas Energéticas e Nucleares, São Paulo, SP, BR.
authors.forename: Maria Fatima Guarizo
authors.initials: MF
authors.lastname: Klingbeil
authors.affiliation: Centro de Pesquisa Experimental, Instituto Israelita de Ensino e Pesquisa Albert Einstein - IIEPAE, São Paulo, SP, BR.
authors.forename: Renata Machado
authors.initials: RM
authors.lastname: Soares
authors.affiliation: Laboratório de Técnicas Especiais, Hospital Israelita Albert Einstein - HIAE, São Paulo, SP, BR.
authors.forename: Roberta
authors.initials: R
authors.lastname: Sitnik
authors.affiliation: Department of Estomatology, Faculdade de Odontologia, Universidade de São Paulo - USP, São Paulo, SP, BR.
authors.forename: Décio Dos Santos
authors.initials: Ddos S
authors.lastname: Pinto Junior
authors.affiliation: Centro de Tecnologia das Radiações, Instituto de Pesquisas Energéticas e Nucleares, São Paulo, SP, BR.
authors.forename: Monica Beatriz
authors.initials: MB
authors.lastname: Mathor
authors.affiliation: Department of Estomatology, Faculdade de Odontologia, Universidade de São Paulo - USP, São Paulo, SP, BR.
authors.forename: Fabio Daumas
authors.initials: FD
authors.lastname: Nunes
authors.affiliation: Centro de Pesquisa Experimental, Instituto Israelita de Ensino e Pesquisa Albert Einstein - IIEPAE, São Paulo, SP, BR.
authors.forename: Patricia
authors.initials: P
authors.lastname: Severino