The Inhibitor of Growth (ING) gene family is a group of tumor suppressor genes that play important roles in cell cycle control, senescence, DNA repair, cell proliferation, and apoptosis. However, inactivation and downregulation of these proteins have been related in some neoplasms. The present study aimed to evaluate the immunohistochemical profiles of ING3 and ING4 proteins in a series of benign epithelial odontogenic lesions. Methods: The sample comprised of 20 odontogenic keratocysts (OKC), 20 ameloblastomas (AM), and 15 adenomatoid odontogenic tumors (AOT) specimens. Nuclear and cytoplasmic immunolabeling of ING3 and ING4 were semi-quantitatively evaluated in epithelial cells of the odontogenic lesions, according to the percentage of immunolabelled cells in each case. Descriptive and statistics analysis were computed, and the p-value was set at 0.05. Results: No statistically significant differences were found in cytoplasmic and nuclear ING3 immunolabeling among the studied lesions. In contrast, AOTs presented higher cytoplasmic and nuclear ING4 labeling compared to AMs (cytoplasmic p-value = 0.01; nuclear p-value < 0.001) and OKCs (nuclear p-value = 0.007). Conclusion: ING3 and ING4 protein downregulation may play an important role in the initiation and progression of more aggressive odontogenic lesions, such as AMs and OKCs.

Congenital granular cell tumor is an uncommon benign oral lesion of uncertain histogenesis that affects the alveolar ridge region of newborns. The present study aims to report an unusual congenital granular cell tumor case, emphasizing clinical, morphological, and immunohistochemical aspects. A 10-day-old newborn patient attended the stomatology service with a nodular pedunculated lesion of normal color located in the anterior region of the superior alveolar ridge. Thus, the diagnostic hypothesis was congenital epulis, and an excisional biopsy was performed. Histopathological analysis revealed features consistent with the diagnosis of congenital granular cell tumor. In addition, we performed immunohistochemical staining for vimentin, Ki-67, and S100. The patient has been under follow-up with no clinical signs of recurrence. Due to its rarity, the analysis of congenital granular cell tumor’s clinicopathological characteristics enables an adequate diagnosis and treatment.