The Effects Of Dihydroartemisinin On The Proliferation And Infestation Of Human Lung Adenocarcinoma Cell Line A549 And The Expression Of MMP-9

Lung cancer is the number one cause of cancer-related mortality in the world. The mortality and morbility of lung cancer are increasing every year. Non small cell lung cancer(NSCLC) accounts for approximately 80% of all kinds of lung cancer cases, which is not sensitivity to chemotherapy andradiotherapy, and the 5-year survival rate for NSCLC remains lower than 15%. Artemisinin is an effective anti-malaria ingredient which extracted from Artemisia annua leaves, which is the new configuration anti-malaria medicine which our country first discovered. Dihydroartemisinin (DHA) is a strongly active artemisinin-based medicine in the all derivatives, which is returns to original state by artemisinin after four hydrogen boron sodium becomes, has the unique peroxide bridge structure. Because DHA has the good absorption, distributed broad, excretion and metabolism rapid, highly effective, low poison, and so on , moreover its oral administration biology exploitability is high, the anti-malaria function is also artemisinin 4～8 times, therefore receives the widespread attention more and more. Study found that in recent years, DHA besides may the antimalaria, in vivo and outside have the anti-tumor function. Raises the tumour cell to the different organization to carry on the examination discovery, DHA dialog hemopathy, the melanin lump, the colon cancer, the prostate gland cancer and breast cancer cell line is highly sensitive. In the present study, we examined whether dihydroartemisinin could inhibited the proliferation of human lung adenocarcinoma cell line A549 cells, in order to look for a new method for the treatment of NSCLC. This study has been devided into two parts:Part 1 The effects of dihydroartemisinin on the proliferation and apoptosis of A549 cells Objective: To investigate the effects of dihydroartemisinin on the proliferation and apoptosis of A549 cells.Mothods: 1. MTT assay was performed in vitro to evaluate the proliferation inhibition effects of dihydroartemisinin on human lung adenocarcinoma cell line A549 cells. 2. The cell cycle distribution was evaluated with flow cytometer. 3. The apoptosis induction effects of A549 cells were studied by electron microscope observation.Results: 1. Dihydroartemisinin inhibited the proliferation of human lung adenocarcinoma cell line A549 cells in a time-dependent and concentration-depended manner. The IC50 value was 580nmol/L. 2. Cell cycle analysis showed that A549 cells underwent G0/G1 phase arrest under exposure to dihydroartemisinin. After incubation with dihydroartemisinin 0,250,500,750 nmol/L, the percentages of A549 cells in G0/G1 phase were 33.71%,49.26%,57.03%,72.04% respectively, they were significantly higher than group control(P<0.01). 3. Electron microscope apoptotic change was observed in A549 cells after treatment with 580nmol/L dihydroartemisinin at 48 hours: pro-apoptosis cell has cavitations and blebbing; apoptosis cell has obvious cytoplasm condensation, nuclear fragmentation, chromatin compaction and segregation.Conclusions: 1. Dihydroartemisinin inhibited cell proliferation of A549 cell lines in a time-dependent and concentration-depended manner. 2. Dihydroartemisinin suppressed proliferation by inducing G0/G1 phase arrest. 3. There were apoptosis changes in morphologic electron microscope after treatment with dihydroartemisinin in A549 cells. Dihydroar- temisinin could induce apoptosis in A549.Part 2 The effeets of dihydroartemisinin on the growth and metastsis of human lung adenocarcinoma in mice and the expression of MMP-9.Objective: To investigate the effeets of dihydroartemisinin which have different concentration on the growth and metastsis of human lung adenocarcinoma in mice and the expression of MMP-9.Methods: The mice with human lung adenocarcinoma were used in this study, which were gavaged respectively with dihydroartemisinin (25, 50, 100mg/kg), and the control group were gavaged distilled water. Then the weight,volum and the metastatic foci on organs and lymph node were determined; 2. The expression of matrix metalloproteinase-9(MMP-9) of lung adeno- carcinoma was observed.Results: 1. Dihydroartemisinin inhibited the proliferation of lung adenocar- cinoma in a concentration-depended manner. Compare with the control group, the second group and the third group were significantly higher than group control (P<0.01), and the metastatic foci on organs and lymph node were not determined; 2. All concentration dihydroartemisinin can remarkably influence the expression of MMP-9.Conclusions: 1. Dihydroartemisinin of high concentration can inhibit cell proliferation of human lung adenocarcinoma in mice; 2. The expression of MMP-9 reduces in all groups.