SP1 and lung cancer: We found that transcription factor 2 (TFAP2 also known as AP2), c-Myc, and nuclear transcription factor Y subunit alpha (NF-YA) promote the transcription of USP22 gene, while SP1 and activating transcription factor 3 (ATF3), a member of the ATF/CREB family of transcription factors, which may represent a potential tumor suppressor in lung cancer [26], inhibit the transcription of USP22 gene in NSCLC cells.