Abstract
Head and neck cancers are the sixth most common cancer in the world and the predominant type of which consist of squamous cell carcinomas (head and neck squamous cell carcinoma, HNSCC). Besides tobacco smoking and alcohol consumption, human papilloma virus (HPV) infection is the third leading cause of the occurrence of HNSCC. The presence of HPV is a distinct group of head and neck cancers exhibiting epidemiological, histopathological, clinical and prognostic differences opposed to the typical HNSCC. HPV positive HNSCC normally have a favorable prognosis compared with HPV negative HNSCC, so biomarkers suitable for the early detection of HPV positive HNSCC should be developed urgently to improve patient outcomes. HPV DNA screening is sensitive, but probably not useful because of the high prevalence of oral HPV and low risk of HNSCC. MicroRNAs (miRNAs) constitute a class of small non-coding RNAs that act as post-transcriptional regulators of gene expression. Since miRNAs have a role in the cancer development and HPV status may affect the miRNAs expression pattern in HNSCC, the specific of miRNAs' expression in HPV positive HNSCC may expound the role of HPV in HNSCC and be new biomarkers for the early detection of HNSCC. More excitingly, saliva as proximal biofluid in the context of HNSCC contains a good deal of miRNAs. These miRNAs are stabile and may be suitable for noninvasive biomarkers of HNSCC.