CDKN2A and neoplasm: They also reported that mutations in the telomerase reverse transcriptase (TERT) promoter were related to early stages, whereas the amplification of genes encoding fibroblast growth factors FGF3, FGF4, and FGF19 or cyclin-D1 and polymorphisms in p53 and cyclin-dependent kinase inhibitor 2A genes were implicated in advanced stages of aggressive tumours.