CyclinD1 and p57(kip2) as biomarkers in differentiation, metastasis and prognosis of gastric cardia adenocarcinoma.

OBJECTIVE: This study aims to investigate the expression and significance of p57(kip2) and cyclinD1 in gastric cardia adenocarcinoma (GCA). p57(kip2) is a negative regulator in the cell cycle. On the contrary, cyclinD1 is a positive regulator of cell cycle progression.

METHODS: Thirty-two cases of GCA tissues and adjacent non-cancerous tissues were collected for this study. Immunohistochemistry and fluorescence qualitative PCR was used to determine the level of p57(kip2) and cyclinD1 in GCA and its adjacent non-cancerous tissues. Furthermore, the correlation between the mRNA/protein and GCA clinical pathologic parameters were analyzed, and the relationship of p57(kip2) and cyclinD1 in GCA were also evaluated.

RESULTS: The expression of p57(kip2) significantly lower in GCA (P = 0.036), and there was a significant correlation in the different degrees of differentiation (P < 0.05). Furthermore, median survival time was 41 months for patients with high mRNA expression of p57(kip2). This was longer compared to patients with low mRNA expression of P57(kip2) (37 months, X2 = 4.788, P = 0.029).The expression of cyclinD1 was significantly higher in GCA(P = 0.002), and was significant correlated to clinical stage(P<0.05). Median survival time was 34 months in patients with high mRNA expression of cyclinD1, which was shorter than in patients with low expression of cyclinD1 mRNA (41 months, X2 = 4.071, P = 0.044). The protein expression of p57(kip2) was not correlated to the protein expression of cyclinD1 (P = 0.55).

CONCLUSION: The expression of p57(kip2) and cyclinD1 are likely to suppress or promote the tumorigenesis and progression of GCA.