Prognostic significance of p53 in the cancer of the larynx.

p53 is a nuclear phosphoprotein acting as a transcription factor to regulate cell cycle progression and apoptosis, mediated by a number of target genes. p53 mutant proteins have lost a) the ability to act as sequence-specific transcription factors and b) their tumour suppressive properties. As p53 is the most commonly mutated gene in human cancer, including laryngeal squamous cell carcinoma, an aggressive and most frequent tumour of head and neck, it has attracted a great deal of interest as a prognostic factor, diagnostic tool and therapeutic target. This article reviews the current understanding of the prognostic significance of p53 in laryngeal squamous cell carcinoma. Immunohistochemical staining techniques and molecular genetics demonstrated that p53 activation is an early event in laryngeal squamous cell carcinogenesis but can not be used as a reliable prognostic marker.