[Relationship between gastric cancer and gene amplification of p14 and mdm2].

Background & Objective: Some genes are related to the occurrence of tumor. p53 is one of these kinds of gene. Mdm2 and p14 can modulate the function of p53. However, the reports about the function of mdm2 and p14 in gastric tumor are rare. The aim of this study was to observe the change of oncogene mdm2 and suppressor cancer gene p14 in gastric cancer cell and to investigate the relationship of mdm2, p14 with gastric cancer.

Methods: A total of 55 gastric mucosal biopsy specimens were enrolled, including 10 of normal gastric mucosa and 45 gastric tumor, which were proved pathologically as adenoma, including 15 poorly, moderately, and well differentiated specimens, respectively. The mRNA expression of mdm2 and p14 in gastric cancer were identified by reverse transcription polymerase chain reaction (RT-PCR), and the relationship of mdm2, p14 with gastric cancer was analyzed.

Results: (1) There was significant difference of the expression positive ratio of mdm2 mRNA between gastric tumor and normal gastric tissues (73.3% vs. 40%) (P< 0.05) [93.3% for the well differentiated specimens, 80.0% for the moderately differentiated specimens, and 46.6% for the poorly differentiated specimens]. There was significant difference between any two groups of the three specimens (P< 0.05). (2) There was no significant difference of the expression positive ratio of p14 mRNA between gastric tumor and normal gastric tissues (60.0% vs. 50.0%) (P >0.05) [60.0% for the well differentiated specimens, 66.6% for the moderately differentiated specimens, and 53.5% for the poorly differentiated specimens]. There was no significant difference between any two groups of the three specimens (P >0.05).

Conclusion: The mRNA expression of mdm2 is closely correlated with the progression of gastric cancer. The relationship between p14 and gastric tumor has not been tested in this study and further study will be needed.