In Vitro Antitumor Activity And Mechanism Of L-threose Nucleoside Phosphonate Analog XA-1

Nucleoside analogs have always played an irreplaceable role in the field of antiviral and antitumor treatments.Therefore,the research and development of new nucleoside compounds has attracted more and more attention from pharmaceutical workers.The death toll of breast cancer accounts for 11.6%of the total cancer deaths among women in China.Breast cancer is one of the tumors with high morbidity and mortality.In order to meet the needs of clinical treatment,it is urgent to find more effective and highly targeted breast cancer treatment drugs.The group designed and synthesized a series of 4'-methyl-3'-O-phosphonate-L-threose furanoside analogs using D-xylose as the starting material.The subject screened the obtained compounds for antitumor activity in vitro,and found a 2-fluoroadenine nucleoside analog XA-1 Which has good anti-breast cancer activity,and then a system of antitumor effect and mechanism of action on XA-1 in vitro.this study found its potential antitumor value and provided experimental basis for further new drug development.The main research contents of this thesis are as follows:1.A series of L-threose nucleoside phosphonate compounds was screened for antiviral and antitumor activity on different tumor cell lines by using of MTT experiments.The results showed that compound XA-1 significantly inhibited different tumor cells.Therefore,compound XA-1 was selected as the target compound for further research.Later experiments showed that compound XA-1 had better anti-tumor activity on human breast cancer cells.Therefore,breast cancer MCF7 and MDA-MB-231 were selected as the cell line for further study of compound XA-1.Subsequently,the effects of compound XA-1 on breast cancer cell clone formation were tested by clone formation experiments,and the effect of compound XA-1 on breast cancer cell morphology was observed with an inverted microscope.It was proved again that compound XA-1 has obvious inhibitory ability on breast cancer cells.2.To study the mechanism of compound XA-1 on DNA damage,cell cycle and apoptosis of breast cancer cells in vitro.The effects of compound XA-1 at different concentrations on breast cancer cell apoptosis,cell cycle,and cell mitochondrial membrane potential level JC-1 were detected by using flow cytometry.The effects of compound XA-1 on the expression of related proteins such as DNA damage and cell cycle,as well as the effect of compound XA-1 on the expression of mitochondrial apoptosis pathway and Caspase family pathway related proteins were examined by Western Blotting experiment.For further research,flow cytometry experiments were used to detect the effects of the inhibitor NSC663284 and compound XA-1 on the cell cycle and apoptosis of breast cancer.Western Blotting experiment was used to detect the effects of the inhibitor NSC663284 and compound XA-1 on the breast cancer cell cycle.The effect of protein and Caspase family apoptosis pathway related protein expression.Through this series of experiments,the antitumor mechanism of compound XA-1 on breast cancer cells was studied.Compound XA-1 first inhibits the PI3K/Akt pathway and then regulates the expression of cycle-related proteins by inducing DNA damage in breast cancer cells,causing G2/M cycle arrest Lag,and finally inhibit breast cancer cell proliferation and exert its anti-tumor effect.3.The effects and mechanism of compound XA-1 on breast cancer cell migration in vitro were studied.The effect of compound XA-1 on breast cancer cell migration was tested using a scratch test.The effects of MMP family and EMT-related proteins in breast cancer cells by Western Blotting use of.It was proved that compound XA-1 can inhibit the EMT process of breast cancer cells and promote the expression of MMP2 protein,thereby blocking the migration of breast cancer cells.In summary,this paper explores the effects of compound XA-1 on the proliferation,apoptosis and migration of breast cancer cells in vitro through a series of experimental studies described above,and preliminary proof of its value in antitumor.On the one hand,compound XA-1 regulates the ATM-Chkl/Chk2-cdc25c pathway by inducing DNA damage in breast cancer cells,causing G2/M phase arrest of breast cancer,thereby inhibiting breast cancer cell proliferation and exerting its anti-tumor effect.On the other hand,compound XA-1 can inhibit breast cancer cell migration by inhibiting the EMT process of breast cancer cells,and exerting its anti-tumor effect.