| hsMAD2(Human, mitotic arrest deficient-2) is one of the most important checkpoints that monitor the activities of the spindle in the process of mitosis. Uptilt now it has been established that this kind of genes like hsMAD2 may control the primary carcinogenesis, Since invalidity of the checkpoint controlled by MAD, ie. Spindle assemble checkpoint will result in deformation of chromosome and instability of genome.Primary human hepatocellular carcinoma, HCC is one of the common malignancies in the digestive system. It has been revealed in epidemiological and etiological research data that HCC has become one of the major diseases that endanger human kings and its incidence rate tends to increase remarkably. However, the mechanism of HCC has not been understood yet. No report of researches on relation between HCC and hsMAD2 has been made. My research concerned is described as the following:1, hsMAD2's expression and distribution were examined in 39 cases of HCC, 15 cases of cancerous surrounding liver tissues, 26 cases of hepatocirrhosis tissues and 3 cases of HCC cell lines with immunohistochemical techniques and histopathological abservation. It was found that there was an hsMAD2 expression in 58.97%(23/39) of HCC tissues, in 100%(15/15) of cancerous surrounding liver tissues, and in 92.31%(24/26) of hepatocirrhosis tissues butno expression in the 3 cases of HCC cell lines. Expression of hsMAD2 in cases of HCC was not associated with the pathological grades of HCC, while there was a significant difference between HCC tissues and cancerous surrounding liver tissues (P<0.01) and liver cirrhosis tissues(P<0.01). Therefore, it suggested that the expression of hsMAD2 might be associated with early pathogenesis of HCC and that the expression rate of hsMAD2 in HCC tissues dropped remarkedly compared with that in cancerous surrounding liver tissues and hepatocirrhosis.2, Eukaryon expression carrier of hsMAD2, pcDNA3.1-hsMAD2 was transferred into HepG2 cells of HCC cell lines, and its effect on HepG2's growth was abserved with gene transfection techniques. It was proved that hsMAD2 could be transferred into HepG2 cells with immunocellulochemical method, Western Blot, etc. Through observation on its cellular morphology and measurement of the growth curve and mitosis index, effects of hsMAD2 on HepG2 cells' growth and proliferation were analyzed. It was found that there was no remarkable change in the growth rate and proliferation of HepG2-hsMAD2 cells. Cell cycle of HepG2-hsMAD2 cells was measured with Flow cytometry (FCM) results showed that ratio of G2 and S stage increased while ratio of G1 stage decreased. But there was no significant difference. It was revealed that there were no obvious effects on cells which have been transferred into hsMAD2 gene.3, Nocodazole's action on cells: the growth rate of HepG2-hsMAD2 which was treated with 50nM Nocodazole, a spindle retarder, dropped significantly and G2 stage block occurred, while there was no obvious change in HepG2 processed by Nocodazole. Therefore, it was shown that hsMAD2 played a role as checkpoint and induced a cycle block in the cell treated by Nocodazole.In this research it was revealed that hsMAD2's expression in HCC tissues was decreased or absent and was absent in HepG2 cells. No obvious effects on the cells were be found which have been transferred into hsMAD2 gene; As to HepG2-hsMAD2 treated with Nocodazole, G2 stage block occurred, and cell's growth was inhibited, here hsMAD2 played a role as checkpoint. Further studies on hsMAD2 will help clarfy the mechanism of HCC and develop gene therapy for HCC.
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