Prevalence of HPV16 L1 protein in oral biopsies: A diagnostic study from Ecuador

This study was designed to investigate the expression of HPV16 L1-protein in biopsies of oral mucosa samples. The expression of HPV16 L1 protein was investigated in biopsies taken from oral mucosa from patients who required pathological diagnosis of oral lesions. Seventy-two samples were incubated with anti-L1 protein monoclonal antibodies and protein detection was revealed with diaminobenzidine. Expression of L1 protein was performed by a pathologist blinded for tissue diagnosis under light microscopy. Most of the lesions of oral mucosa were present in lining mucosa (75 %) and the most frequent lesion were mucocele (n = 17, 23.6 %), epithelial hyperplasia (n = 6, 8.33 %), fibroma (n = 5, 6.9 %) and inflammatory hyperplasia (n = 5, 6.9 %). L1 protein expression was observed only in five (6.9 %) samples (two squamous cell carcinomas, two epithelial hyperplasia, and one gingival hyperplasia). We concluded that L1 expression in oral biopsies presented a low frequency in oral mucosal biopsies samples.