The Research On The Activity Of Osimertinib And Dexamethasone In EGFR Inhibitor-resistant Non-small Cell Lung Cancer

Objectives In this study,it was proposed that through the in vitro cell culture and a tumor-burdened mice experiment,we want to prove the new targeted cancer drugs Osimertinib and anti-inflammatory drugs dexamethasone could inhibit tumor angiogenesis,and provide the corresponding data support for clinical guidance.Methods Different concentrations of Osimertinib,dexamethasone and combinati on were applied to non small cell lung cancer cell lines H1975 respectiv ely.After 24,48,72 h application,tetramethyl azo thiazole bluecolorimetry(MTT)was used to detect cell proliferation inhibition;after the lung canc er mice model established,the mice divided into four groups: the Osimerti nib group,dexamethasone group,combined treatment group and control group.All the mice should be continuous measure the mice tumor volum e and weight,and draw the tumor growth curve and the mice weight ch ange curve respectively.Simultaneous determined the related to angiogen esis of HIF-1a and the NF-κB expression,then compare the information of every group.Results MTT was used to detect the inhibition rate of H1975 of dexamethas one group and combined treatment group,with SPSS data analysis and LSD data comparison,it found that the cell inhibition rate of dexamethas one with in 24,48,72 h does not exist significant difference with different drugs concentration groups(P≥0.05).the cell inhibition rate of Osimertini b with in 24 h,48h and 72 h does showed significant differences(P≤0.05).Compared with Osimertinib group,Drug combination with in 24 h,48h a nd 72 h did not exist significant difference with different drugs concentrati on groups(P≥0.05).When dexamethasone and Osimertinib was used alone,the speed of tumor change and weight change were significantly lower than control group.The optimal group was the combination group and it’s tumor gro wth and weight change significantly slow than other groups,which had si gnificant difference(P≤0.05).Simultaneous was used to determined the HIF-1a and the NF-κB expression of every group,the expression of HIF-1a and NF-κB was significantly lower in every groups(P≤0.05),the opti mal group was the combination group and exist significant difference wit h other groups(P≤0.05).Compared with Osimertinib group,the S-ABC met hod can help find that the combination group shows less blood vessel a nd more whiteness in inner structure of the tumor mass under the micro scope.Conclusions Dexamethasone had no obvious effect on the inhibition of lung cancer cells.Osimertinib can significantly inhibited lung cancer growth and the growth of vascular.Compared with Osimertinib group,Drug combination did not enhance the inhabitation of H1975.Dexamethasone can significantly reduce the HIF-1a,NF-κB expression,which can suppress inflammation and tumor angiogenesis,Osimertinib combined with dexamethasone showed the most strong inhabitation of H1975.Through the mice tests,we can found that Osimertinib combined with dexamethasone can synergistically inhibit tumor cell growth and control the weight of the mice,the combined group of mice showed the best mental state.Compared with individual drugs,combination therapy has obvious advantages in many ways.