| Tumor is one of the three killers of human health. So, more attention has been focused on the mechanism of tumor metastasis.Selectin is a family of cell adhesion molecular, which has three members such as L-selectin, P-selectin and E-selectin. They are specifically expressed adhesion molecular on surface of activated endothelium, platelets and leukocytes .Recently it has been demonstrated that selectin induce tumor cells adhesion to endothelium and platelets, which can improve tumor metastasis and diffusion in blood vessel.L-selectin is continually expressed in the greater number of white blood cells, such as neutrophilic granulocyte, mononuclear cell, basophilic granulocyte. eosinophilic granulocyte,most of T lymphocytes and B lymphocytes, which is the homing receptor of lymphocytes. T cells' hybrid tumor cells which specifically metastasize to lymph node highly express L-selectin. Non-Hodgkin lymphoma cells invading the lymph node which is considered to play key role in metastasis, while those propagated in peripheral tissues rarely express L-selectin. Fawn Qian et al demonstrated that L-selectin can facilitated metastasis to lymph node in a transgenic mouse modle of carcinogenesis. By injecting tumor cells, they have found only tumor cells of L-selectin expression can be detected in lymph nodes. Borsig et al demonstrated L-selectin expression on white blood cells can effect tumor metastasis in vivo and weaken metastasis of cancer of colon in P,L-selectin double deficient mice, which proved synergistic effects of L- and P-selectin in facilitating tumor metastasis. The murin hepatocarcinoma cell line (Hca-F) were established by Professor Ling Mao-ying from distant hybridization Km murin ascetic hepatocarcinoma cell line H22 which can specifically metastasis to lymph nodes. When they are injected into 615 mouse's heel, the potential of lymph nodes metastasis is higher than 80%, providing the ideal model to study the mechanism of lymphogenoue metastasis. Our previous results showed: the CK marker of epidermal and AFP marker of liver cancer of Hca-F are positive in immunostaining, while the T lymph cells' surface marker CD3 and B lymph cells' surface marker CD20 of Hca-F cells' are negative in immunostaining, suggesting that Hca-F cells were originated from liver cells, exclude the possibility of lymphoma. FCM.RT-PCR and Western blot results showed that both Hca-F and Hca-P cells have the expression of L-selectin, but their expression level is difference. Hca-F cells' average expression is about 4 times as high as that of Hca-P cells. We have proved that L-selectin's expression level is positively related to Hca-F cells and Hca-P cells potential metastasis ability.In this study, by FCM we analyze the L-selectin's expression on the surface of Hca-F cells in culture progress and the relationship between L-selectin's expression level and potential metastasis ability.The flow cytometric's result shows that Hca-F cells express L-selectin with high level. There are two kinds of subgroup in Hca-F cell ,the large and the small. L-selectin is mainly expressed on the surface of the large cell.In the progress of culturing of Hca-F in vitro,.There are no significant changes on the positive rate , fluorescence intensity of L-selectin expressed on the surface of Hca-F cell and the percents of the cell of 1-3 generation.. But from the fouth generation the positive rate and fluorescence intensity of L-selectin expressed on the surface of Hca-F cultural cells decrease as well the percents of the small cell significantly increase. We inject the 4-6 generation Hca-F cells into the 615 mice intraperitoneally which expression of L-selectin decrease.The positive rate and fluorescence intensity of L-selectin expressed on the surface of the large cell extracted from ascites obviously increases as well the small cell decrease.The results above shows that: There is high expression of L-selectin on Hca-F cells.. L-selectin is expressed mainly on the large Hca-F cells .The expression of L -selectin has d...
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