Expression And Implication Of Fas/Fasl, P27 And PCNA In Colorectal Carcinoma

Objective: Formerly people considered the reason of tumor happen is cell proliferate and differentiate abnormality to result in cell proliferate exorbitant. Lately with the apoptosis theory to institute, people begin to understand new knowledge about the cause of tumor happen. In tumor cells exist not only proliferate exorbitant but also apoptosis abnormality. Recently people discover a new couple of immunization component :Fas(CD95, Apo-1) and FasL(Fas ligand,CD95L), it has intimate relation between Fas/FasL mediated apoptosis and tumor happen. Fas and FasL become research, focus about molecular biology and apoptosis theory. Between eukaryote cell growth differentiate carcinomatous change and cell cycle ,it have closely relationship. Cell cycle factor include: cyclin, cyclin dependent kinases (CDKs) andcyclin dependent kinase inhibitors ( CDKI) .p27 protein is the product of p27 gene, it is a cyclin dependent kinase inhibitors by recently discovered. p27 can restrain cell proliferation, because p27 restrain cell transformation from Gl stage to S stage.. Take place and development of tumor have intimate relationship with abnormality expression of p27. Proliferating cell nuclear antigen (PCNA) is an assistant protein of DNA polymerase 8 7 it is a necessary material of DNA reproduction. PCNA content have intimate relation with cellproliferation condition.Colorectal carcinoma have high incidence rate in our country. To describe and investigate the expression of Fas/FasL in different locations of colorectal carcinoma tissues and the expression of p27, proliferating cell nuclear antigen (PCNA) in colorectal carcinoma.Methods: 50 consecutive colorectal carcinoma and 10 normal colorectal specimens were collected and continuous paraffin slices were made from the normal colorectal tissue,5cm distance from colorectal neoplasm tissue, paracarcinoma tissue and colorectal neoplasm tissue of each specimen. Each specimen made 4 continuous paraffin slices, one of the continuous paraffin slices to be used by HE dyeing, the purpose is to verify the diagnose, two of the slices were used by S-P(Streptavidin/Peroxidase) immunohistochemical staining. The expression of Fas/FasL were analyzed with immunohistochemistry in order to find the difference in the above-mentioned tissues. Immunohistochemical staining was also used to detect p27, PCNA in the above-mentioned normal colorectal tissues and colorectal carcinoma tissues.Results: The positive Fas/FasL staining was found in cell membrane and cytoplasm. The positive p27 staining was found in cell nuclei and cytoplasm. The positive PCNA staining was found in cell nuclei.The Fas expression positive rate in carcinoma was 62%(31/50), in normal tissues was 100%(10/10). In colorectal carcinoma the expression of Fas was lower evendeletion, but the expression of FasL was obviously enhance, the positive rate was 86%(43/50), in normal tissues the positive rate only 10%(1/10). The dynamic analysis was used to the four tissues, we found the continuous variational tendency of Fas/asL expression. From normal tissues the expression rate of Fas become gradually weaken, FasL expression rate become gradually reinforcement. p27 high expression rate for normal tissues was 100%( 10/10). but for colorectal carcinoma tissues was only 54%(27/50). The number of PCNA positive cells in normal tissues and carcinoma tissues was (22.37+6.05) and (50.91+16.06) . Compared with colorectal carcinoma tissues. paracarcinoma tissues and normal colorectal tissues, the Fas expression positive rate (62% vs 84 %vs 100%) and the FasL expression positive rate (86% vs 66%vs 10%) also showed significant difference (P<0.05) . Compared with normal colorectal tissues and 5cm distance from colorectal carcinoma tissues the Fas expression positive rate (98%vs100%) and the FasL expression positive rate (12% vs 10%) also showed no significant difference (P>0.05) . Compared with normal colorectal tissues and colorectal carcinoma tissues the expression of p27 and PCNA both showed significant difference (...