Expression of p27~(kip1),skp2,p53 gene in colorectal adenocarcinoma and its significance

Objective:To investigate the expression of p27kip1,skp2 and p53 in colorectal carcinoma. Methods:The expression of p27kip1,skp2,p53 gene mRNA and protein in the progression of colorectal adenocarcinoma were investigated by reverse transcription polymerase chain reaction(RT-PCR) and immunohistochemistry. Results:The mRNA expression of p27kip1 and p53 in colorectal adenocarcinoma were lower than that in normal colon tissue(P0.01);the level of skp2 mRNA expression in colorectal adenocarcinoma was higher than that in normal colon tissue(P0.01). Immunohistochemistry demonstrated that the positive rates of p27kip1 was significantly lower in colorectal adenocarcinoma (25%) than in normal colon tissue(90%, P0.001) and colorectal adenoma(55%, P0.001);the positive rates of skp2 and p53 were significantly higher in colorectal adenocarcinoma (70% and 66.67%) than in normal colon tissue(10% and 5%, P0.001) and in colorectal adenoma(50% and 25%, P0.001). The expression level of p27kip1 and skp2 protein was associated with the pathologic grade,invasion depth,clinical stage and lymph node metastasis of colorectal carcinoma(P0.05). Overexpression of p53 was strongly related to the invasiveness,Dukes' stage,and metastasis of colorectal adenocarcinoma (P0.05). There was an inverse correlation between the expression of p53 and p27kip1. The expression level of p27kip1 and skp2 were inversely correlated,while the expression level of p53 and skp2 protein were positively correlated. Conclusion: The expression of p27kip1,skp2 and p53 might play critical roles in occurrence and development of colorectal tumor through their alteration.p27kip1 expression is inversely correlated with p53 and skp2 expression,which suggests that p27kip1 expression is regulated by p53 and skp2 in cell cycle progression.Combined detection of p27kip1,skp2 and p53 gene is valuable for the assessment of malignant biological behavior in colorectal carcinoma