The Studys Of Loss Of Heterozygosity, MRNA And Protein Expression Of P57～(kip2) In Human Hepatocarcinoma

Objective: To study the loss of hererozygosity(LOH) of P57^kip2 and expressions of P57^kip2 mRNA & protein in human hepatocellular carcinoma (HCC) in order to explore the molecular mechanism of hepatocarcinogenesis.Methods: LOH of three microsatellite loci(D11S1397 D11S1318 and D11S4046) were detected where the P57^kip2 gene is in by using PCR-Polyacrylamide gel electrophoresis - silver staining method in 30 cases of HCC. Immunohistochemistry staining and in situ hybridization (ISH) were also used to show the expression of P57^kip2 protein and mRNA in pericancerous cirrhosis and HCC.Results: 1. LOH detected: LOH was not identified in 30 cases on three microsatellite locies. 2. Expression of P57^kip2 mRNA: There were no expressions in normal liver tissue. Expressions both in pericancerous cirrhosis and hepatocellular carcinoma were 26. 67%(8/30). There was no significant difference between the expressions in high differentiated HCC tissues and low differentiated HCC tissues. 3. Expression of P57^kip2 protein: There were no expressions in normal liver tissue. Expressions in precancerous cirrhosis and hepatocellular carcinoma were 56. 67% (17/30) and 63.33 %( 19/30) respectively. There was no significant difference between the expressions in high differentiated HCC tissues and low differentiated HCC tissues. 4. There was no correlation between the LOH of three locies and the expression of P57^kip2mRNA; there was no correlation between the LOH of three locies and the expression of P57^kip2 protein. 5. There was positive correlation between expression of P57^kip2 mRNA and expression of P57^kip2 protein.Conclusion: 1. The disorder expressions of P57^kip2 mRNA and protein indicated that P57^kip2 may be involved in hepatocarcinogenesis and prognosis. 2. LOH was not identified on three microsatellite locies , which indicated that there may be another reason for the disorder expression of P57^kip2.