Deletion and mutation of p16~(INK4a) gene in primary gastric carcinoma

OBJECTIVE:To investigate the role of deletion and mutation of p16~(INK4a) gene which plays in the pathogenesis of primary gastric carcinoma. METHODS: A total of 62 gastric carcinoma tissues and their adjacent normal tissues and 10 nontumorous gastric tissues from gastritis patients were studied. The homozygous deletion was detectyed by multiple PCR analysis and mutation by PCR-SSCP and DNA sequencing followed. RESULTS: Four cases had p16 INK4a gene homozygous deletions and the deletion rate was 6.5%(4/62), 2 cases had deletion in exon 1 and the other 2 cases in exon 3, and no deletion of exon 2 was found. The PCR-SSCP and DNA sequence analysis showed 1 case mutation at intron 1(1.6%, 1/62). No aberrant single strand at PCR-SSCP in exon 2 and exon 3 was detected. No deletion and mutation were found in tumor-adjacent normal tissues and nontumorous gastric tissues. CONCLUSION: Low frequency of homozygous deletion and rare mutation of p16 INK4a gene occurre in gastric carcinoma.