| Background: Carcinoma is one of theleading causes of death diseases in the world .the goal of preventing and treating cancer is to decrease incidence rate and mortality rate of cancer. The natural plants in xinjiang possess the resistant characteristics due to its unique geographical environment and climate condition, which provides us a chance to find novel anti-tumor agents. According to the survey of natural plant resources there are about one thousand kinds of natural plants in xinjiang. effects of one hundred kinds of plants among them have been studied by supporting on all sides.however,the chosed cancer cell lines in the antitumour experimental studies were mainly the cancer cell lines of respiratory and digestive system, so we should choose more cancer cell lines from different systems and detect systemly the anti- tumour effects of them for finding new anti-tumour drugs. Amid: to detect systemly anti-tumour effects and mechanisms of the two extracts, and to set up a pattern for screening new anti-tumuor agents from natural plants. Methods: (1) the growth inhibitory effects of two extractstowards seven kinds of cultured human cancer cell lines,ie.Hela, Bcap-37,T24, HO8910, MGC-803, BEL-7404, SW1990. were evaluated by MTT assay ( 2 ) the antitumur activity of the two extracts in vivo by using two kinds of the replanting models in Kunming mice(the solid sarcoma -180 and ascites sarcoma-180) were tested respectively. ( 3) the related anti-tumour molecular mechanisms of the two extracts were studied through detecting the apoptopsis rates and change of cell cycle of the treated cancer cells. (4) the synerdistic effects of antitumor and decreasing side effects of two extracts in chemotherapy by using human cerical cancer transplanted in nude mice were explored. Results: the results was that: (1) cancer cells treated by the extracts with the dose of 0.1 g/ml under the light microscope usually were observeded similar morphological changes including cell shrikage, nuclear condensation, and so on ,and the growth inhibitory rates ranged from 24.25% to 91.01%, which comfirmed that the tew extracts had the inhibitory growth activity towards these human cancer cell lines, however, the antitumor action of extracts with two doses (O.OOlg/ml, 0.0001 g/ml) hadnt been find.Animal experiment domonstrated, compared to the untreated mice, the mean weight and volume of tumor tissues of the treated solid sarcoma-180 mice were much less (p<0.05), and the growth inhibitory rates of the treated mice ranged from 24.92% to 65.70%, demonstrating that the two extracts possessed obviously antitumor effects on the solid sarcoma -180 mice.The results suggested the doses of the two extracts, all three doses (2000mg/kg^ lOOOmg/kg and 500mg/kg) of Pleurotus erngii, 2000mg/kg Blackcurrant, put off death of the treated ascites sarcoma-180 mice compared to the untreated ascites-180 mice. (2) The treated cancer cells cuold be observed under microscope characteristic morphology of apoptosis , such as rounded and small cancer cells, chromtin condensation, nuclei displayed a smooth spherical periphery containing relatively evenly distributed condensationchromatin? large patches of condensation chromatin distributed in the nuclear periphery, a few spherical apoptosis bodies and so on. Which revealed that these extracts had induced apoptosis of the four cancer cell lines a The apoptosis rates of treated cancer cells, measuring by flow cytometry using Annexin V/PI straining methods, ranged from 8.1% to 72.0%, were significantly higher than that of untreated cancer cells, suggesting the two extracts induced the apoptosis of cancer cells,and the two cancer cell Iines(ho8910 andT24) were more sensitive to the Blackcurrant extract.The results showed that the two extracts upregulated the exprossion of bax and caspase-3 protein and downregulated the exprossion of bcl-2 protein, which suggested the two extracts induced apoptosis of T24 cells by activitiing bcl-2/bax-caspase-3 pathway, measured the change of the cell cycles of the four cancer cell lines by flow cytometry. The rate of cells in each phase of the cell cycles of treated cells changed compared to the untreated cells, suggesting that the two extracts could arrested the cancer cell progression at different phases and further inhibited proliferation of cancer cells. (3 ) according to these results, their possible macnanism is that : the two extracts could induced apoptosis of cancer cells by activitied bcl-2/bax-caspase-3 pathway, and, at the same time, arrested the cell cycle progression to inhibite the proliferation of cancer cells. (4) the synerdistic effects of antitumor and decreased side effects of two extracts (Pleurotus erngii andBlackcurrant) in chemotherapy were studied by using human cerical cancer transplanted in nude mice.A significantly lower of final volumes and mean weight of timour tissues was observed in nude mice exposed to combination of 5-Fu plus Pleurotus erngii extract compared with the nude mice exposed to 5-Fu alone, which showed that combinatian of 5-Fu plus Pleurotus erngii extract was more effective in inhibiting tumor growth.However, the Blackcurrant extract hadnt the synerdistic effects of antitumor.The results also revealed the Pleurotus erngii extract coulddecreased side effects by increasing the number of white blood cells in mice treated by 5-Fu. A significantly higher of the exprossion of baxN pi 6 and caspase-3 protein of timour tissues was observed in nude mice exposed to combination of 5-Fu plus Pleurotus erngii extract compared with the nude mice exposed to 5-Fu alone, suggesting the synerdistic effects of Pleurotus erngii extract related to the upregulation of the exprossion of bax^ pi6 and caspase-3 protein.Conclusion: (1) the two extracts with the dose of O.lg/mg has the growth inhibitory effects towards seven kinds of cultured human cancer cell lines,ie.Hela,Bcap-37,T24,HO8910, MGC-803, BEL-7404, SW1990.(2) the two extracts possess obviously antitumor effects on the solid sarcoma-180 mice and put off death of the ascites sarcoma-180 mice.(3) the two extracts can induce apoptosis and arrest the cell cycle of cancer cells. (4 ) the Pleurotus erngii extract has the synerdistic effects and decreasing side effects in chemotherapy.which relate to the upregulation of the exprossion of bax*. pi 6 and caspase-3 protein.
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