Experimental Study On The Effect Of Ibuprofen On Human Breast Cancer Cell Line MCF-7and Its Mechanism

Breast cancer is a common female malignant tumor. According tocurrent epidemiological survey, the worldwide incidence of breast cancerhas ranked the1st in female malignancy and the worldwide incidence rateof breast cancer still increases annually.In China, the incidence rate ofbreast cancer increases about3%per year, which has become the fastestin the world.Breast cancer not only causes physical and psychologicalsuffering on women,but also brings great losses to the patient’s family andthe whole society.So how to improve breast cancer treatments safelyeconomically effectively has become an issue concerned for the medicalprofession and patient groups.Ibuprofen is a kind of non-steroidalanti-inflammatory drugs which has been used as anti-inflammatoryanalgesic drugs in clinic for many years,and is known as the safestnon-steroidal drugs.According to recent studies,ibuprofen can inhibitprostate cancer,colon cancer,bladder cancer,liver cancer and other kind ofcancers, but the effect of ibuprofen on breast cancer and its mechanismhas been reported rarely,The study aims to study the effect of ibuprofenon P53wild-type human breast cancer cell line MCF-7and itsmechanism in vivo and in vitro, which may provide new ideas andexperimental basis for the foundation of further involvement of ibuprofenin clinical treatment of breast cancer.By this experimental study, we can acquire the following results:(1)By the MTT colorimetric analysis, ibuprofen can inhibit the proliferation of human breast cancer cell line MCF-7.(2)By PI staining flow cytometry analysis,ibuprofen can causeG0/G1phase arrest in human breast cancer cell line MCF-7.(3)By Hoechst33258staining and Annexin V-FITC/PI doublestaining flow cytometry detection of apoptosis,we observed fromdifferent angles that ibuprofen can promote human MCF-7breast cancercell line apoptosis in vitro.(4)By western blotting analysis of cell cycle related proteins,wefound that phosphorylated ATM (ser1981), phosphorylated P53(ser15),P21upregulated.(5)By western blotting analysis of apoptosis-related proteins,we foundthat phosphorylation of P53(ser15)，cleaved Caspase9upregulated, Survivindownregulated， mitochondrial membrane potential decreased by JC-1staining method.(6)Comet assay and western blotting analysis of γ-H2AX showedDNA was damaged.(7)We established successfully human breast cancer cell line MCF-7nude mouse tumor model and found that the group treated with ibuprofenin which tumor weight reduced compared to the control group withoutdrug treatment.Mitochondrial membrane potential decreased by JC-1staining method.By TUNEL assay, we found that tumor cells in the tumorbody existed apoptosis phenomenon.The immunohistochemical detectionof apoptosis related protein pP53(ser15)、Survivin、cleaved Caspase9showed that the expression of pP53(ser15)、cleaved Caspase9comparedto the control group upregulated, the expression of Survivin compared tothe control group downregulated.In summary,we can conclude:(1) Ibuprofen can arrest human breast cancer cell line MCF-7 proliferation in vitro by blocking cell cycle progression, promoting cellapoptosis and DNA damage,and this effect have a trend that it isenhanced with concentration increases and time extends.(2) Ibuprofen can cause in cell cycle arrest in G1phase in vitrothrough pATM-pP53-P21pathway.(3)The effects of ibuprofen in vitro on promoting cell apoptosiswork through P53-mitochondria-Caspase9and P53-Survivin-Caspase9pathway.(4)Ibuprofen can inhibit tumor growth in human breast cancer cellline MCF-7nude models and the machanism of this effect may haverelations with the upregulation of apoptosis related proteins pP53(ser15)、cleaved Caspase9and the downregulation of Survivn.