Differential expression of microRNAs miR-21, miR-31, miR-203, miR-125a-5p and miR-125b and proteins PTEN and p63 in verrucous carcinoma of the head and neck.

AIMS

To investigate the expression of microRNAs miR-21, miR-31, miR-203, miR-125a-5p and miR-125b and proteins phosphatase and tensin homologue (PTEN) and p63 in verrucous carcinoma (VC) of the head and neck.

METHODS AND RESULTS

Thirty cases of VC, 50 cases of conventional squamous cell carcinoma (SCC) and 30 samples of normal epithelium of the head and neck were included. Real-time polymerase chain reaction and immunohistochemistry were used to analyse the expression of microRNAs and proteins, respectively. In comparison to normal epithelium, miR-21 was overexpressed in both VC and SCC and miR-31 was overexpressed in VC and in well- and moderately differentiated SCC. Levels of miR-203 were elevated in VC but unaltered or reduced in SCC, and levels of miR-125a-5p and miR-125b were reduced in VC but unaltered in SCC. PTEN was down-regulated in both VC and SCC, whereas p63 was down-regulated in VC but up-regulated in SCC. Differential expression of p63 in VC correlated inversely with the expression of miR-21 and miR-203.

CONCLUSIONS

Differences between VC, SCC and normal epithelium in expression profiles of investigated molecules indicate their association with the pathogenesis and clinicopathological characteristics of VC. Our results suggest that some microRNAs and proteins, particularly miR-125b, miR-203 and p63, might be useful in the diagnosis of VC.