4 The transition fromG1 to S stage in normal cell cycle is largely regulated by cyclin D1, a 45 kDa protein thatwas shown to be a critical factor in regulating cell proliferation, migration, anddifferentiation. Cyclin D1 has been extensively studied in the context of oral cancer and aremarkable connection was found between cyclins and oncogenesis. 5 Moreover, cyclin D1 gene amplification was shown to be prevalent in head andneck SCC. 6 Here, CCND1 is linked to lip and oral cavity carcinoma.