Mitosis Of Spindle Poisons Induced Mechanism Of Polyploidy Tumor And Sensitivity To The Influence Of Drugs-study Of Apoptosis Pathway

Objective:The chemotherapy is an important part of the comprehensive treatment. Many studies show that the physical chemistry drug primarily induced apoptosis of the tumor cells to achieving a therapeutic purpose, to be an important marker of the evaluation of anticancer drug effect is whether the drugs induce apoptosis of the tumor cells, but many chemotherapy drugs are faced with the multi drug-resistance gene's problem. Many spindle of toxic substances (paclitaxel/vincristine/nocodazole) is first-line drugs of tumor chemotherapy. This prompts us to the spindle of toxic substances induced cells polyploidization which are likely in relation to multi drug-resistance gene.In the ordinary way normal cell cycle occures abnormal (as polyploidy) will start the apoptosis in the tumor cells. If there is also more normal cells cycle control mechanism. The study found that the spindle of toxic treated to cells, there are some of the cell Occurs mainly apoptosis into many times, some of the cells occurs mainly polyploidization.why are some cells will slowly recover from the spindle checkpoint arrest and re-enter G1 as tetraploidy? why these polyploidy cells do not activate the mechanism of apoptosis? It may be related to the lost control of the cell cycle and the restrainted apoptosis pathway.Bcl-2 family is an important factor of regulatory apoptosis in mammal cells, current research topics that Bcl genes and related protion overexpress which depressed apoptosis is an important factor of the tumorigeness and multi-drug resistance phenomenon.Therefore, a greater significance is the study of Bcl-2,Bax which is expressed by nocodazole induced from the standpoint of the apoptosis.Methods:1,The group:With Nocodazole treated two breast cancer MDA-MB-231 and HCC1806 Oh,6h,12h,24h 36h 48h 72h, and according to different time harvesting cells, and no medicine against a blank cell.2,The detection of the cell cycle:Flow cytometry detect the effection that MDA-MB-231 cells and HCC1806 cells were treated by Nocodazole, analyze cell cycle, determin the cycle.3,The morphology of apoptsis in inverted microscope:Observation MDA-MB-231 and HCC1806, and after handling the Nocodazole different points of harvest time, inverted microscope observation the morphology change of MDA-MB-231 and HCC1806 cellsï¼›PI dyeing streaming cells instrument to detect the impact of MDA-MB-231 and HCC1806 the apoptosis cells by Nocodazole treated; westen blot detected caspase9, caspase3 of MDA-MB-231 and HCC1806.4,Westen blot detect MDA-MB-231 cells and HCC1806 cells:detected anti-apoptosis protein Bcl-2 and pro-apoptosis protein Bax of expression of Bcl-2 familyResults:1,Nocodazole to the influence of the cell cycle in MDA-MB-231 and HCC1806Nocodazole treated HCC1806 is characterized by the apoptosis cells; in contact with the drug 6h,HCC1806 cells began to appear G2/M period of stagnation, stagnates utterly at 24h after G2/M, which more and more form to the apoptosis after 72h in HCC1806 cells; but which more and more form to the tetraploid cells after 72h in MDA-MB-231..2,Nocodazole to the influence of the apoptosis in MDA-MB-231 and HCC1806With Nocodazole treat MDA-MB-231 and HCC1806 6h, Cells began to turn round and 24h after all, with contact extended,HCC1806 cells size is smaller, deformation, phratries nuclear shrink, and the apoptosis body were formed for a typical the apoptosis morphology change.MDA-MB-231 Cells with the contact extened, such as cell sizeswelling,the larger nucleus that typical polyploidy cell were progressively increased, the main cells is polyploidy in 72h.Westen blot result display,there is expressed the Caspase3,Caspase9 of apoptosis marker protion in HCC1806 cells that treated by Nocodazole at 24h.3,Expression of Bcl-2/Bax protion in MDA-MB-231 and HCC1806After Nocodazole treated HCC 1806, persist expression of Bax protion;and protion expression be markedly increased after Nocodazole treated HCC 1806 36h,48h; But it is not expression in MDA-MB-231.Bcl-2 overexpression from 36h to 72h in MDA-MB-231 by Nocodazole treated.Conclusion:Overexpression of Bcl-2 can keep back the apoptosis of breast cancer cells by Spindle poisons induced, which is probably one reason of polyploidy tumor's mechanism, and mechanism of multi drug-resistance.