Comparative Immunohistochemical Analysis of p53 and -SMA in Ameloblastoma, AOT and OKC

O. M. Adesina, K. E. Adebiyi, O. A. Effiom, G. O. Omoniyi-Esan, F. J. Owotade, O. A. Fatusi, B. Kolude, O. O. Odujoko, A. Ladeji

Abstract

OBJECTIVES: Ameloblastoma is a benign but highly infiltrative
tumour, a behaviour that is lacking in adenomatoid odontogenic tumour
but partly shared by the odontogenic keratocyst which possesses a
unique intrinsic growth potential with marked ability for destroying
bone and a high tendency recurrence. High frequency of stromal
myofibroblasts (assessed with alpha smooth muscle actin (α-SMA)
correlates with aggressive behaviour while p53-cell cycle regulation
system is critical in odontogenic tumours with immunoreactivity
signifying prognostic status. This study aims to determine and
compare the immunoreactivity of these selected tumours to p53 and
α-SMA in order to establish if a relationship exists between the
frequency and pattern of distribution of myofibroblasts and the
behaviour of these lesions.

MATERIALS AND METHODS: 69 blocks of ameloblastoma, and
23 each of adenomatoid odontogenic tumor (AOT), and odontogenic
keratocyst (OKC/KCOT) were retrieved. Immunohistochemistry
technique was applied for evaluation of these two markers staining
with primary antibodies to p53 and -SMA and the frequency and
pattern of distribution of myofibroblasts and immunoreactivity to
p53 analysed and compared using ANOVA. p was set at <0.05.

RESULTS AND CONCLUSION: Immunoreactivity to p53 and
α-SMA was highest in ameloblastoma (solid compared to unicystic)
with highest mean positive cells to α-SMA (29.7±20.1) and p53
(28.3±24.5) in plexiform ameloblastoma. This suggests that
ameloblastoma was the most aggressive of tumours studied. Different
pharmacological agents that can regulate stromal MF are useful aids
to decrease the need for radical surgery in extensive and aggressive
odontogenic tumours. WAJM 2022; 39(3): 248–255.

Keywords: Ameloblastoma, AOT, OKC/KCOT, p53, α-SMA,
myofibroblasts, odontogenic tumours, immunoreactivity.