Interferon?-1b And Cyclooxygenase-2 Inhibitor Suppress The Proliferation Of Renal Cancer Cell And Xenografts In Nude Mouse

Background and objectivesThe ranal cell carcinoma(RCC)is one of the common malignant tumors in the urinary system.In our county,RCC account 2~3% of all malinant tumors and after bladder cancer,the morbidity of RCC in urinary system is secondly high.At the same time,with the improvement of quality of life and deterioration of people's live environment,the morbidity of ranal cell carcinoma present a upward trend with each passing year.Due to the RCC is a kind of urinary malignent with multi-drug resistence gene,and therefore it is not so sentitive to the traditional rediotherapy and chemotherapy.At present,the comprehensive treatment is considered to be applyed to the RCC and the methods including surgical therapy,immunotherapy,biotherapy and targeted therapy and so on.Especcially for the advanced-stage RCC without surgical therapy chances,these methods could be a priority.Interferon(IFN)is small molecular protein which has a variety of biological activities.The first significant findings about IFN is anti-virus activity and the follow-up studies revealed the other potential functions of IFN,such as being an important role to regulate cells' multiplication process and body's immune system,enhancing the biological activities of NK cells,inhibiting tumor angiogenesis,inducing tumor cells apoptosis and killing the tumor cells directly,and provides a new approach to treat malignent tumors.Cyclooxygenase-2(COX-2)was attracted attention by reducing the morbidity of colon cancer among people who took the cyclooxygenase inhibitor for a long time.Preliminary studies have shown that COX-2 keep a high expression in various tumors.It can promote tumor angiogensis and has a close association with tumor's proliferation,invasion,metastasis,etc.Also,the expression of Cyclooxygenase-2 has a significant positive correlation with tumor's malignent degree.There were many studies indicated that COX-2 specific inhibitor could inhibit the tumor growth by accelerating cancer cells' apoptosis,suppressing tumor angiogensis and then improved the prognosis of patients.Base on these above,study of this experiment adopts IFN?-1b and COX-2 specific inhibitor(NS398)to co-culture with renal cancer cell and therapy the xenograft in nude mouse to observe the inhibition effection exert by drug combination as well as discuss related mechanisms.Methods1.Use different concentrations of IFN?-1b and NS398 co-culture with ACHN,CCK-8 was used to detect the effection caused by these medicine on the proliferation of ACHN.2.Use IFN?-1b and different concentraions of NS398 co-culture with ACHN for a period of time,western blot was used to test the change of expression level of anti-apoptotic protein Bcl-xl and COX-2 in ACHN.3.Establishment xenograft in nude mice with ACHN,Mice were randomized into the treatment groups—IFN?-1b group,NS398 group,IFN?-1b+NS398 group and the control group.Experimental groups were treat with corresponding medicines and phosphate buffered saline(PBS)was applied to control group.Measure and record the xenograft regularly.4.Stip out the xenograft at the end of treatment,immunohistochemistry assay was used to test the expression difference of Vascular Endothelial Growth Factor(VEGF)in the xenograft of each group.Results:1.The results of CCK8 showed that different concentrations of IFN?-1b and NS398 co-cultured with ACHN could inhibit the proliferation of tumor cells and the concentration of the medicine is larger,the effect could be stronger.Drug combination is superior to single therapy and the effect is dose-dependent.2.The western blot assay comfirmed that an inhibition reaction of the expression Bcl-xl and COX-2 in ACHN,in a dose-dependent manner,was tested by mixing culture of ACHN with IFN?-1b and NS398.3.Growth curve of xenograft in nude mice revealed that,as time passed by,the volumes of xenograft in IFN?-1b group,NS398 group and IFN?-1b+NS398 group were all smaller than control group.The volume of tumor in IFN?-1b+NS398 group is smallest among treatment groups.4.The expression level of VEGF in the xenografts among each treatment group was suppressed in different degrees compared with control group in the immunohistochemistry assays and the IFN?-1b+NS398 group worked best.Conclusion1.IFN?-1b and NS398 can effectively inhibit the proliferation of ACHN,induce the tumor cells' apoptosis,drug combination can exert synergistic inhibitory effect.2.Both IFN?-1b and NS398 can efficiently suppressed the expression of COX-2 in ACHN,drug combination runs better than alone.Therefore,COX-2 could be considered as a new target for ranal cancer patient's non-surgical therapy.3.IFN?-1b and NS398 might exert its anti-tumor effect by inducing the apoptosis of cancer cells,inhibiting tumor angiogensis,etc.