PCNA and oral cavity squamous cell carcinoma: Nrf2 also leads to the increased transcription of the proliferating cell nuclear antigen (PCNA) gene and the activation of the Notch signaling pathways, which augments the cellular level of NOTCH1 intracellular domain (NICD1) and Hes Family BHLH Transcription Factor 1 (HES1) genes, leading to enhanced proliferation of oral squamous cell carcinoma cells [120].