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Updated: Aug 19, 2026

Gene Regulation and Targeted Therapy in Gastric Cancer Peritoneal Metastasis: Radiological Findings from Dual Energy CT and PET/CT
Published on: January 22, 2018
[The significance of p21 expression in gastric cancer]
Abstract:
We examined the expression of p53, p21, cyclin D1, E, and PCNA in 75 cases of gastric cancer by immunohistochemical study and the expression of p21 RNA in cases by in situ hybridization. The rate of stage III, IV cases of p53(+) p21(-) group was significantly higher than that of any other groups. The apportinately 3-year survival rate of p53(+) p21(-) group was significantly lower than either that of p21(+) p53(-) or p53(-) p21(-) group. The 3-year survival rates of positive cases were significantly lower than those of negative cases on both cyclin D1 and E. The positive rate of cyclin E of the p53(-) p21(+) group was significantly lower than that of the p53(+) p21(-) group. The average PCNA Labeling. Index (LI) of the p53(+) p21(-) group was significantly higher than that of the p53(-) p21(+) group. The 3-year survival rate of cases with expression of p21 RNA was higher than that of cases without p21 RNA. Average PCNA L1 of cases with expression of mutant-type p53 was high and the number of poor prognostic cases in cases with expression of mutant-type p53 was large. In contrast, the average PCNA LI of cases with expression of p21 was low and the number of good prognostic cases with expression of p21 was large. These results suggest that p21 suppresses synthesis of DNA via cyclin E and PCNA.
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