Premium
p53 Gene mutations and overexpression of p53 product in cancerous and noncancerous biliary epithelium in patients with pancreaticobiliary maljunction
Author(s) -
Matsubara Toshiki,
Funabiki Takahiko,
Jinno Osamu,
Sakurai Yoichi,
Hasegawa Shigeru,
Imazu Hiroki,
Ochiai Masahiro
Publication year - 1999
Publication title -
journal of hepato‐biliary‐pancreatic surgery
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.63
H-Index - 60
eISSN - 1868-6982
pISSN - 0944-1166
DOI - 10.1007/s005340050120
Subject(s) - cancer research , epithelium , gene product , gene , pathology , medicine , biology , gene expression , genetics
To investigate the molecular mechanisms of the high incidence of carcinogenesis in the biliary epithelium of patients with pancreaticobiliary maljunction, we examined p53 gene mutations, loss of heterozygosity of p53 , and overexpression of p53 gene product in the cancerous and noncancerous biliary epithelium of 27 patients with pancreaticobiliary maljunction. Mutations of the p53 gene were examined by polymerase chain reaction‐single strand conformation polymorphism and a direct sequencing method. Loss of heterozygosity of the p53 gene was determined using a double‐targeted fluorescence in situ hybridization method. Expression of p53 gene product was examined using immunohistochemical staining. Mutations of the p53 gene were found in 4 of 5 biliary carcinomas (80%) and in 10 of 26 noncancerous biliary lesions (38.5%). Point mutations of the p53 gene were detected at codons 207, 212, and 217 on exons 5 through 8. The incidence of p53 gene mutations on exons 5, 6, 7, and 8 was 12.9%, 36.4%, 0.0%, and 13.8%, respectively. Loss of heterozygosity of p53 was shown in 72% of the cells obtained from the cancerous lesion, and in an average of 14% obtained from the noncancerous lesions. Overexpression of p53 protein was found in 57.1% of carcinoma, and in 31.3% of the noncancerous lesions. These results suggest that p53 gene mutations are involved in the carcinogenesis of biliary epithelium in patients with pancreaticobiliary maljunction.