TP53 and neoplasm: The essential functions and characteristics of p53 are considered to be as follows: (1) p53 is a transcription factor that activates its specific target genes [10]; (2) p53 exerts tumor-suppressive effects through cell cycle arrest, apoptosis, DNA repair, and anti-angiogenesis [11]; (3) suppressed p53 levels have an important role in the maintenance of stem cell and cancer stem cell phenotypes [12,13]; and (4) p53 is one of the most mutated genes in a broad range of human cancers [14].