title: Comparison of RNA Extraction Methods for Molecular Analysis of Oral Cytology.
abstract: The aim of this study was to compare three methods of RNA extraction for molecular analysis of oral cytology to establish the best technique, considering its concentration and purity for molecular tests of oral lesions such as real-time reverse transcriptase reaction.
  
  
  
  The sample included exfoliative cytology from the oral cavity mucosa of patients with no visible clinical changes, using Orcellex Rovers Brush®. The extraction of total RNA was performed using the following three techniques: 30 samples were extracted by Trizol® technique, 30 by the Direct-zolTMRNA Miniprep system and 30 by the RNeasy mini Kit. The absorbance was measured by spectrophotometer to estimate the purity. The estimated RNA concentration was obtained by multiplying the value of A260 (ng/mL) by 40. Statistical analysis of the obtained data was performed using GraphPad Prism 5.03 software with Student t, analysis of variance and Bonferroni tests, considering p ≤0.05.
  
  
  
  Trizol® group revealed higher average concentration, followed by Direct-zolTMand Rneasy group. It was observed that the RNA Direct-zolTMgroup had the highest purity, followed by RNeasy and Trizol® groups, allowing for the two ratios.
  
  
  
  Considering all aspects, concentration, purity and time spent in the procedures, the Direct-zolTMgroup showed the best results.
authors: Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, UNESP - Univ Estadual Paulista, Săo José dos Campos, Săo Paulo, Brazil.; School of Dentistry, Universidade Braz Cubas, Mogi das Cruzes, Brazil.
authors: Mônica Ghislaine Oliveira
authors: MG
authors: Alves
authors: Oral Medicine, Oral Surgery and Implantology Unit, Faculty of Medicine and Dentistry, Santiago de Compostela, Spain .
authors: Mario
authors: M
authors: Pérez-Sayáns
authors: Human Anatomy and Embriology Area; Functional Biology and Health Sciences Department. University of Vigo, Pontevedra, Spain .
authors: Maria-Elena
authors: ME
authors: Padín-Iruegas
authors: Oral Medicine, Oral Surgery and Implantology Unit, Faculty of Medicine and Dentistry, Santiago de Compostela, Spain .
authors: Maria Dolores
authors: MD
authors: Reboiras-López
authors: Department of Pathology, Forensic Sciences, University Hospital and School of Medicine of Santiago de Compostela, Santiago de Compostela, La Coruńa Spain .
authors: José Manuel
authors: JM
authors: Suarez-Peńaranda
authors: Department of Medical Oncology Hospital Clinico Universitario of Santiago de Compostela, La Coruńa, Spain .
authors: Rafael
authors: R
authors: López-López
authors: Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, UNESP - Univ Estadual Paulista, Săo José dos Campos, Săo Paulo, Brazil .
authors: Celina Faig Lima
authors: CF
authors: Carta
authors: Smoking Cessation Program, Area of Cardiology, Heart Institute, University of Săo Paulo, School of Medicine, Hospital das Clínicas, Săo Paulo, Brazil.
authors: Jaqueline Scholz
authors: JS
authors: Issa
authors: Oral Medicine, Oral Surgery and Implantology Unit, Faculty of Medicine and Dentistry, Santiago de Compostela, Spain .
authors: Abel
authors: A
authors: García-García
authors: Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, UNESP - Univ Estadual Paulista, Săo José dos Campos, Săo Paulo, Brazil .
authors: Janete Dias
authors: JD
authors: Almeida
keywords: RNA; cytology; oral; oral exfoliative cytology