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. In this study we evaluated the performance of 7 previously identified, potential mRNA biomarkers of OSCC in saliva samples of Hungarian patients. 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 was quantified from each sample using real-time quantitative PCR. 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. In 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. Lastly, 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.
Keywords: Biomarker; OSCC; Saliva based diagnostics; Saliva mRNA; qPCR.