ORAL HEALTH MAY AFFECT THE PERFORMANCE OF MRNA-BASED SALIVA BIOMARKERS FOR OSCC

Abstract

Aim(s): Oral squamous cell carcinoma (OSCC) has a dismal 50% five-year survival rate, emphasizing the need to develop reliable and sensitive tools for early diagnosis. The aim of this study was to evaluate the performance of 7 previously identified, potential mRNA biomarkers of OSCC in saliva samples of Hungarian patients.

Methods: Thirty one consecutive patients with recently diagnosed and untreated OSCC were recruited from the Department of Oral Surgery (Faculty of Dentistry, University of Debrecen, Hungary), between June 2011 and May 2012. Thirty age- and gender-matched subjects, and 29 young healthy subjects, consecutively admitted for dental check-up at the Department of Restorative Dentistry and Department of Periodontology (Faculty of Dentistry, University of Debrecen, Hungary), represented the control groups. Exclusion criteria were: a prior history of cancer, coexisting diabetes, autoimmune disorder or contagious diseases. RNA was isolated and reverse transcribed from filtered saliva samples. Expression of the putative OSCC biomarkers (DUSP1, OAZ1, H3F3A, IL1B, IL8, SAT and S100P), 2 biomarkers of inflammation (IL6 and TNFα) and 8 putative normalizing genes were quantified from each sample using real-time quantitative PCR. The study was approved by the Ethics Committee of the University of Debrecen The study participants were all invited, and gave their written, informed consent. Detailed characteristics of OSCC patients and controls are summarised in a poster.

Results: In contrast with previous studies, the expression pattern of the 7 mRNA biomarkers was similar between OSCC patients and age-matched control patients in the Hungarian patient population. On the other hand, 5 of the 7 mRNA biomarkers were present at significantly higher levels in saliva samples of OSCC patients when compared to young control patients. The best biomarker combination could distinguish only the OSCC vs. young control patients, but not the OSCC vs. age-matched control patients.

Conclusion: The significant differences between our results and previous studies, and the clinical characteristics of the patients suggest that inflammatory processes in the oral cavity may affect the performance of the 7 putative salivary mRNA biomarkers. Since IL6 mRNA was quantifiable in the majority of OSCC cases, but only in a few control samples, salivary IL6 mRNA may be utilized as part of a biomarker combination to detect OSCC.