PHF5A and head and neck squamous cell carcinoma: Several studies, including ours, have revealed that PHF5A can exert a regulatory function in the onset and progression of an array of malignancies, including endometrial cancer [7], lung cancer [8–10], breast cancer [11], colorectal cancer [12, 13], pancreatic cancer [14], gastric cancer [15] and head and neck squamous cell carcinoma [16], by mediating abnormal alternative splicing of target genes, regulating crucial signaling pathways, or acting as a proto-oncogene/protein, transcription factor or cofactor.