Biomarkers that predict recurrence in odontogenic keratocysts

Objectives: Odontogenic keratocysts are one of the three most common odontogenic cysts. They have a distinct biological behaviour that tends to be more aggressive with a higher propensity for recurrence than other odontogenic cysts. Our aim was to compare the expression of cell cycle and structural proteins that may help, in combination with histological features, predict the recurrence of keratocysts. Methods: Tissue microarrays were constructed from a cohort of 110 keratocysts, 35 dentigerous, and 37 radicular cysts from the tissue archive in the Unit of Oral and Maxillofacial Pathology, University of Sheffield. The keratocyst cohort included cysts known to subsequently recur (n = 57) and those with no evidence of recurrence (n = 53). All cysts were immunostained for CD56, geminin, Ki67, p63, Cyclin D1, and cytokeratins 5/6, and visually assessed according to a modified Allred scoring system. One-way ANOVA tests and independent sample t-test were carried out to evaluate the differences in expression levels of the biomarkers between the three cyst types and keratocyst subtypes respectively. Results: Odontogenic keratocysts showed significantly increased expression of CD56, cyclin D1 and Ki67 (p<0.001) compared to radicular and dentigerous cysts. Within the odontogenic keratocyst sub-groups, non-recurrent cysts showed increased expression of CD56, Cyclin D1, geminin, Ki67 and p63 compared to those known to subsequently recur (p = <0.046). Conclusions: Geminin and CD56 expression may be useful in predicting keratocyst recurrence. The pattern of expression of these and other markers together with certain histological features may be useful to pinpoint patterns that predict keratocyst recurrence.