Notch1 and CyclinD1 expression and significance in jaw ameloblastoma: an immunohistochemical analysis.

PURPOSE: Ameloblastoma (AM), a frequently encountered odontogenic epithelial neoplasm, demonstrates complex molecular pathogenesis involving dysregulation of cellular signaling networks. This study investigated the clinicopathological significance of Notch1 signaling pathway activation and its downstream effector CyclinD1 in jaw ameloblastoma progression. METHODS: Immunohistochemical profiling was conducted on 66 archived AM specimens and 23 normal oral mucosa (NOM) controls. Protein localization patterns and expression intensities were systematically analyzed using chi-square tests, Fisher's exact test, and Spearman's rank correlation (significance threshold α = 0.05). RESULTS: A notable proportion of jaw AM samples exhibited marked immunoreactivity for Notch1 and CyclinD1 proteins, predominantly localized in the cellular membrane and cytoplasm. Significantly elevated levels of Notch1 and CyclinD1 proteins were evident in AM compared to NOM (P < 0.05). The protein expression levels showed no association with AM subtype (P > 0.05), while a positive correlation between Notch1 and CyclinD1 expression was noted in AM (r = 0.509, P < 0.05). CONCLUSIONS: The coordinated overexpression of Notch1-CyclinD1 axis in ameloblastoma pathogenesis suggests their synergistic involvement in tumor proliferation dynamics. These findings position the Notch signaling pathway as a potential therapeutic target for AM management strategies.