The role of vascular endothelial growth factor in proliferation of odontogenic cysts and tumors: An immunohistochemical study

Abstract

Background: Vascular endothelial growth factor (VEGF) is capable of initiating angiogenesis in
blood vessels and may act as mitogenic agent for epithelium of odontogenic cysts and tumors. This
study was conducted to evaluate the role of epithelial VEGF expression in odontogenic cysts and
ameloblastoma and its correlation with argyrophilic nucleolar organizer region counts to assess
its role in their biological behavior.
Materials and Methods: In this retrospective cross‑sectional study, 45 histologically confirmed
cases, 15 cases of each of keratocystic odontogenic tumors (KCOTs), dentigerous cysts, and
ameloblastomas were examined for immunohistochemical expression for epithelial VEGF, and
argyrophilic nucleolar organizer regions (AgNORs) (used as secondary marker in this study) staining
was done for comparing the proliferative capacity with VEGF.
Results: KCOT shows mild expression within the basal layers and strong expression in the
suprabasal layer whereas, in dentigerous cysts, a majority showed no VEGF expression whereas
ameloblastomas showed strong expression in all cases by stellate reticulum-like cells at the center
of the follicles and suprabasal layers of epithelium. The results of AgNOR counts were higher in
KCOTs as compared to ameloblastoma and least in dentigerous cysts.
Conclusion: VEGF expression by the epithelium of odontogenic cysts and tumors may play a role
in epithelial proliferation via autocrine mechanism as reflected by increased AgNOR counts. The
angiogenic activity via paracrine pathway may be responsible for the difference in growth rate and
neoplastic behavior of the lesions.
Key Words: Argyrophilic nucleolar organizer region associated proteins, odontogenic tumor,
vascular endothelial growth factor