Expressions of PCNA, p53, p21~(WAF-1) and cell proliferation in fetal esophageal epithelia: Comparative study with adult esophageal lesions from subjects at high-incidence area for esophageal cancer in Henan, North China

摘要

AIM: To characterize the expression of p53, p21~(WAF-1) and proliferation-cell-nuclear-antigen (PCNA) in fetal esophageal epithelia and to determine the role of these genes in proliferation of fetal and adult esophageal epithelial cells. METHODS: Immunohistochemical avdin-biotin peroxidase complex (ABC) method was applied to 31 cases of fetal esophageal specimens and 194 cases of adult esophageal specimens to detect the expression of p53, p21~(WAF-1) and PCNA in fetal and adult esophageal epithelia. RESULTS: Both the PCNA positive immunostaining cell number and PCNA positive immunostaining rate in fetal esophageal epithelia (506+-239) were significantly higher than those in adults, including normal epithelia (200+-113) and epithelia with basal cell hyperplasia (BCH) (286+-150) (P<0.05, t test). However, the number of PCNA positive immunostaining cells in adult esophageal dysplasia (719+-389) and squamous cell carcinoma (SCC) (1261+-545) was apparently higher than that in fetal esophageal epithelia (506+-239) (P<0.05, t test). The positive immunostaining rate of P53 was 10 % (3/31) in fetal esophageal epithelia, which was significantly lower than that in adult normal esophageal epithelia (50%), adult epithelia with basal cell hyperplasia (62%), dysplasia (73%) and squamous cell carcinoma (86%) (P<0.05, Fisher's exact test). No p21~(WAF-1) positive immunostaining cells were observed in fetal esophageal epithelia. However, p21~(WAF-1) positive immunostaining cells were observed in adult esophagus with 39% (11/28) in normal, 38 % (14/37) in BCH, 27% (3/11) in DYS and 14% (1/7) in SCC. CONCLUSION: PCNA could act as an indicator accurately reflecting the high proliferation status of fetal esophageal epithelium. p53 may play an important role in growth and differentiation of fetal esophageal epithelium. p21~(WAF-1)may have no physiological function in development of fetal esophageal epithelium.