Role of phosphatase and tensin homolog in pathogenesis of ameloblastoma: An immunohistochemical study

Background: Altered molecular signaling pathways in ameloblastoma have been identified to play a pivotal role in the mechanism of oncogenesis, differentiation, and tumor progression. Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin pathway is one of the signaling pathways that are associated with the pathogenesis of ameloblastoma. Phosphatase and tensin homolog (PTEN) controls cell migration and proliferation. It monitors the level of the Akt and maintains cellular integrity. The present study was aimed to study the immunoexpression of PTEN in ameloblastoma to understand its role in the pathogenesis of ameloblastoma.

Materials and methods: Twenty cases of ameloblastoma and ten cases of normal tooth germ were subjected to immunohistochemical staining against PTEN.

Results: Strong PTEN immunopositivity was seen in the tooth germs, while weak positivity was seen in the ameloblastoma. The immunoscore for PTEN was calculated by adding the percentage score and the intensity score. Seventeen cases showed the reduced PTEN expression in the epithelial component of ameloblastoma. The unpaired t-test showed a statistically significant difference in the mean PTEN immunoscore in tooth germ and ameloblastoma.

Conclusion: The study showed reduced PTEN immunoreactivity, which plays a role in the pathogenesis of ameloblastoma, through Akt pathway.

Keywords: Ameloblastoma; immunohistochemistry; phosphatase and tensin homolog; tooth germs.