Effect Of MiR-34a On The Malignant Biological Behavior Of Lung Adenocarcinoma By Regulating FOXM1 And MTA2

[Objective]To study the effects of miR-34a on malignant biological behaviors such as invasion,migration,cloning,proliferation and of lung adenocarcinoma cells in vitro and in vivo,and possible targets of miR-34a in malignant biological behaviors of lungadenocarcinoma,Verification of miR-34a,MTA2,FOXM1 expression level and miR-34a and MTA2,FOXM1 correlation.[Method]1.Overexpress miR-34a through the biosynthetic agent miR-34a-mimics,compare the cell proliferation and cloning ability of each group through the CCK test and plate cloning formation experiment,and comprehensively evaluate the miR-34a against lung adenocarcinoma A549 and XWLC-05 Effects of proliferation and cloning capabilities.2.Cell scratch test and Transwell migration test to evaluate the effect of miR-34a on the migration ability of lung adenocarcinoma cells A549 and XWLC-05.3.Transwell invasion test was used to detect the cell invasion ability of each group,and to evaluate the effect of miR-34a on the invasion ability of lung adenocarcinoma cells A549 and XWLC-05 cells.4.Through bioinformatics analysis,eight target genes with high relevance to miR-34a,such as MYC,MTA2,FOXM1,FOXP1,MDM4,MYB,ULBP2,and SIRT1,Real-time fluorescence quantitative polymerase chain reaction method was used to detect the expression levels of miR-34a,MYC,MTA2,FOXM1,FOXP1,MDM4,MYB,ULBP2,SIRT1,and the target genes with the highest correlation with miR-34a were selected.5.Establish a model of lung adenocarcinoma subcutaneously transplanted tumor in nude mice,draw tumor growth curve,and analyze tumor weight.RT-qPCR was used to detect the expression levels of miR-34a,MTA2 and FOXM1 in each group of transplanted tumors.[Result]1.The cell growth curve was drawn by CCK method:there was no significant difference in growth curve between blank group and NC group(p>0.05);cell proliferation in miR-34a-mimics group was significantly lower than that in NC group and blank group(p<0.05).2.Tanswell invasion experiment:A549 cell group:The number of invasive cells in miR-34a-mimics group was significantly lower than that in blank group and NC group(p<0.05).There was no significant difference in the number of invasive cells between blank group and NC group(p>0.05).XWLC-05 cells:The number of invasive cells in the miR-34a-mimics group was significantly lower than that in the blank and NC groups(p<0.05).There was no significant difference in the number of invasive cells in the blank and NC groups(p>0.05).3.Cell scratch test:A549 cells:There was no significant difference between the average migration rate of the blank group and NC group to the scratch area(p>0.05).However,the miR-34a-minics group with high expression of miR-34a had a significantly lower average migration rate to the scratch area than the blank group and the NC group(p<0.05).XWLC-05 cells:There was no significant difference between the average migration rate of the blank group to the scratch zone and the average migration rate of the NC group to the scratch zone(p>0.05).However,the miR-34a-mimics group with high expression of miR-34a had a significantly lower average migration rate to the scratch area than the blank group and NC group(p<0.05).4.Tanswell migration experiment:A549 cells:miR-34a-mimics group migratory cell number was significantly lower than the blank group and the NC group(p<0.05),blank group and NC group migrating cell number was not significantly different(p>0.05).XWLC-05 cells:miR-34a-mimics group migratory cells were significantly lower than the blank group and the NC group(p<0.05),there was no significant difference between the blank group and the NC group(p>0.05).5.Formation experiments of plate clones,A549 cells:The average number of clones in the blank group and the NC group were significantly higher than those in the miR-34a-mimics group(p<0.05);there was no significant difference between the blank group and the NC group(p>0.05).XWLC-05 cells:the average number of clones in the blank group and the NC group were significantly higher than those in the miR-34a-mimics group(p<0.05);there was no significant difference between the blank group and the NC group(p>0.05).6.The expression level of MTA2 and FOXM1 decreased most in the miR-34a overexpression group,and the difference was statistically significant(p<0.05).MTA2 and FOXM1 were selected as the targets for subsequent experiments.7.After 5 days of subcutaneous inoculation of tumor cells in nude mice of all groups,all tumors formed.Growth curve of implanted tumor:The growth rate of transplanted tumor in miR-34a group was significantly lower than that in A549-NC cell group(p<0.05);on day 25 of the end time,the average volume of nude mice in A549-miR-34a group was significantly smaller than that in A549-NC cell group(P<0.05);the average mass of nude mice in A549-miR-34a group was significantly lower than that in A549-NC cell group(p<0.05).8.RT-qPCR detected the expression levels of miR-34a,MTA2,FOXM1 in tumor tissues.The results showed that the expression of miR-34a in A549-miR-34a group was significantly higher than that in NC group(p<0.05);The expression levels of MTA2 and FOXM1 in the A549-miR-34a group of 34a were significantly lower than those of the NC group,and the difference was statistically significant(p<0.05).9.The expression of miR-34a in normal tissues of lung adenocarcinoma patients was significantly higher than that of lung adenocarcinoma tissues,and the expression levels of MTA2 and FOXM1 in cancer tissues of lung cancer patients were significantly higher than normal tissues.miR-34a expression was negatively correlated with MTA2 and FOXM1 in lung adenocarcinoma.10.The expression levels of miR-34a,MTA2,and FOXM1 have no significant correlation with lymphatic metastasis and pathological stage in patients with lung adenocarcinoma.[in conclusion]1、miR-34a may inhibit the proliferation,migration,invasion and cloning of lung adenocarcinoma by regulating MTA2 and FOXM1.2、The expression of miR-34a is low in lung adenocarcinoma tissues,while the expression of MTA2 and FOXM1 is up-regulated;miR-34a and MTA2 and FOXM1 are negatively correlated in lung adenocarcinoma tissues.