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.
OBJECTIVE
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 those that 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.


CONCLUSIONS
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.
Xing
Ying
Y
Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Ning
Yu
Y
Ru
Li-Qiang
LQ
Wang
Li-Dong
LD
D000328:Adult; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology*; D002455:Cell Division / Q000502:physiology; D002681:China / Q000453:epidemiology; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000096:biosynthesis*; D004847:Epithelial Cells / Q000502:physiology; D004938:Esophageal Neoplasms / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology*; D004947:Esophagus / Q000166:cytology / Q000196:embryology; D005260:Female; D005333:Fetus; D006801:Humans; D007124:Immunoenzyme Techniques; D015994:Incidence; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis*; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D018809:Proliferating Cell Nuclear Antigen; D016159:Tumor Suppressor Protein p53