BCL-2 AND P53 IMMUNOPHENOTYPES IN PREINVASIVE, EARLY AND ADVANCED ESOPHAGEAL SQUAMOUS CANCER

Aims: An inverse correlation between bcl-2 and p53 expression has been reported in several types of epithelial tumour. The role of bcl-2 and p53 in the development of oesophageal squamous carcinoma has yet to b e established. The expression of bcl-2 and p53 proteins has been evalu ated in the multistage oesophageal tumorigenesis, which progresses fro m normal mucosa to dysplasia (squamous intraepithelial lesion, SIL), t o invasive early and advanced oesophageal squamous cancer, Methods and Results: Sixty-four cases of squamous oesophageal cancer, coexisting with SIL in IS cases, were immunohistochemically analysed for ang over expression of bcl-2 and p53 proteins, Any association of bcl-2 and p53 protein expression with patient survival was also analysed. We observ ed bcl-2 expression that decreased significantly during the progressio n of oesophageal carcinogenesis, A decreasing frequency in the express ion of bcl-2 in advanced oesophageal squamous cancer coincided with fr equent p53 overexpression, bcl-2 expression was correlated with patien t survival by univariate analysis, The association disappeared after a djusting for tumour stage, p53 overexpression showed no association wi th patient survival by either univariate or multivariate analysis. Con clusions: The down-regulation of bcl-2 and upregulation of p53 in adva nced oesophageal squamous cancer suggest that bcl-2 and p53 proteins m ay interact in the progression of oesophageal squamous cancer.