title: Salivary microRNAs in oral cancer.
abstract: OBJECTIVE
  This study investigated the use of three salivary microRNAs (miRNA-21, miRNA-184, and miRNA-145) as possible markers for malignant transformation in oral mucosal lesions.
  
  
  METHODS
  Salivary whole unstimulated samples were collected from a study group of 100 subjects, consisting of 20 clinically healthy controls, 40 patients with oral potentially malignant disorders (PMDs) [20 with dysplastic lesions and 20 without dysplasia], 20 with biopsy-confirmed oral squamous cell carcinoma (OSCC), and 20 with recurrent aphthous stomatitis (RAS) as disease controls. Total RNA was isolated and purified from saliva samples using the microRNA Isolation Kit (Qiagen, UL). miRNA expression analysis was performed using qRT-PCR (Applied Biosystems).
  
  
  RESULTS
  There was a highly significant increase in salivary miRNA-21 and miRNA-184 in OSCC and PMD (with and without dysplasia) when compared to healthy and disease controls (P < 0.001). Conversely, miRNA-145 levels showed a highly significant decrease in OSCC and PMD overall (P < 0.001). RAS cases showed no significant difference from normal controls in any measured miRNA (P > 0.05). The only microRNA to discriminate between OSCC and PMD with dysplasia was miRNA-184. When receiver operating characteristic curves were designed for the three miRNAs, cutoff points delineating the occurrence of malignant change were a fourfold increase in miRNA-21 with specificity 65% and sensitivity 65%, a 0.6 decrease in miRNA-145, with specificity 70% and sensitivity 60%, and a threefold increase of miRNA-184, with specificity 75% and sensitivity 80%. Calculating the area under the curve revealed that miRNA-184 was the only one among the studied miRNAs that provided good diagnostic value.
  
  
  CONCLUSIONS
  Salivary determination of the miRNAs tested might furnish a noninvasive, rapid adjunctive aid for revealing malignant transformation in oral mucosal lesions, particularly miRNA-184.
authors.affiliation: Division of Oral Medicine, Oral Diagnostic Sciences Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.|Department of Oral Medicine and Periodontology, Faculty of Oral and Dental Medicine, Cairo University, Cairo, Egypt.
authors.forename: F
authors.initials: F
authors.lastname: Zahran
authors.affiliation: Department of Oral Medicine and Periodontology, Faculty of Dentistry, October University for Modern Sciences and Arts, 6th October City, Egypt.
authors.forename: D
authors.initials: D
authors.lastname: Ghalwash
authors.affiliation: Department of Medical Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt.
authors.forename: O
authors.initials: O
authors.lastname: Shaker
authors.affiliation: Division of Oral Medicine, Oral Diagnostic Sciences Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: K
authors.initials: K
authors.lastname: Al-Johani
authors.affiliation: Emeritus Professor, UCL, London, UK.
authors.forename: C
authors.initials: C
authors.lastname: Scully
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000032:analysis*; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000175:diagnosis / Q000235:genetics*; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology; D012372:ROC Curve; D012463:Saliva / Q000737:chemistry*; D013281:Stomatitis, Aphthous / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; C541010:MIRN145 microRNA, human; C534424:MIRN184 microRNA, human; C524940:MIRN21 microRNA, human; D035683:MicroRNAs
keywords: miRNA salivary biomarkers; miRNA-145; miRNA-184; miRNA-21; microRNA; oral cancer; oral malignant transformation; potentially malignant disorders