Mehdi Shahabinejad - Department of Oral and Maxillofacial Pathology, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran & Oral and Maxillofacial Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Reza Zare - Oral and Maxillofacial Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Farnaz Mohajertehran* - Department of Oral and Maxillofacial Pathology, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran & Oral and Maxillofacial Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran & Dental Research Center, M
Atefeh Amouzad Mahdiraji - Dental Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.

Background: High prevalence of oral squamous cell carcinoma (OSCC) demands the additional novel biological markers. Due to the established roles of cytokeratin in the prognosis of metastasis evaluation the relation of expression of both CK۷ and CK۲۰ in OSCC compared to the dysplastic oral epithelium biopsies with clinicopathological factors were investigated. Methods: We examined the coordinate mRNA expression of cytokeratin ۷ (CK۷) and cytokeratin ۲۰ (CK۲۰) using quantitative reverse transcription polymerase chain reaction (qRT-PCR) in ۱۱۰ biopsies of oral squamous epithelium samples including ۷۲ tumoral and ۳۸ dysplastic biopsies. We also collected demographic and pathological data including tumor stage and grade from our patients. Results: There was a significant difference in CK۷ and CK۲۰ gene expression between OSCC and dysplastic samples (p< ۰.۰۰۱). Further, their mean expression in OSCC samples was significantly higher compared to dysplastic samples. Relative mRNA levels of CK۷ and CK۲۰ showed that their mean expression in OSCC grade I was significantly lower than other grades (p< ۰.۰۱). The relationship between CK۷ and CK۲۰ mRNA expression and age or gender was not significant (p> ۰.۰۵). Samples in the advanced stage of disease had significantly higher CK۷ and CK۲۰ expression compared to early-stage samples of OSCC specimens (p= ۰.۰۰۱). Conclusions: We found an increase in CK۷ and CK۲۰ mRNA levels in grade III OSCC samples compared to other grades. This finding suggests a potential role for CK۷ and CK۲۰ in oral mucosal carcinogenesis and OSCC prognosis.

CK۲۰, CK۷, Clinicopathological Indices, Cytokeratin, Gene expression, Oral Epithelial Dysplasia, Oral Squamous Cell Carcinoma.