FDI-6 Inhibits The Proliferation And Metastasis Of Colon Cancer By Regulating METTL3/YTHDF1 Via FOXM1

Objective:To investigate the effects and molecular mechanism of FDI-6,FOXM1 specific inhibitor,on the proliferation and metastasis of colon cancer.Methods:1.Clinical specimens of colon cancer were collected,and on the basis of pathological identification by H&E staining,the methylation level of m~6A was detected by colorimetry,and the mRNA and protein expression levels of FOXM1,METTL3 and YTHDF1 were respectively detected by RT-q PCR and Western blot.2.Through TCGA and GSE database analysis,the different expression and pairy-correlation analysis of FOXM1,METTL3,YTHDF1,PCNA and MMP9 in colon cancer and metastatic grade tissues and adjacent tissues were analyzed.3.Human colon cancer cells were cultured in vitro and treated with FDI-6 to observe the expression of FOXM1,METTL3,YTHDF1 and the differences in the ability of the cell proliferation,invasion and migration.Furthermore,the expression of FOXM1,METTL3 and YTHDF1 in the cells was interfered by RNA interference or plasmid transfection,and the effects on the expression of FOXM1,METTL3,YTHDF1,PCNA and MMP9 were observed.Results:1.The mucosal structure of the paracancer colon tissues could be shown lined in an orderly manner while that of colon cancer tissues was disordered.Moreover,compared with the adjacent normal tissues,the proportion of nucleo-cytoplasm was significantly increased,the methylation modification level of m~6A RNA was increased,and mRNA and protein expression levels of FOXM1,METTL3 and YTHDF1were also significantly increased in colon cancer tissues.2.The results of clinical colon cancer tissues combined with the database displayed that comparing with the adjacent tissues,the expression levels of FOXM1,METTL3,YTHDF1,PCNA and MMP9 in colon cancer tissues were significantly increased,and especially with the cancer grade rising.3.FDI-6 inhibited the proliferation,invasion and migration of colon cancer cells down-regulating mRNA and protein expression levels of FOXM1,METTL3,YTHDF1,PCNA and MMP9,and etc.The knock-down or overexpression of FOXM1 can synchronously regulate the expressions of METTL3,YTHDF1 and PCNA.But METTL3 only regulated the expression of YTHDF1,PCNA and MMP9,which did not cause the change of FOXM1 mRNA and protein expression.And YTHDF1 also synchronously regulated mRNA expression of PCNA and MMP9.However,FOXM1 and METTL3 did not change accordingly.Not only FDI-6 and FOXM1 siRNA but also METTL3 siRNA could down-regulate the modification level of m~6A in the two colon cancer cells,and the effect of METTL3 siRNA was more significant.Conclusion:FDI-6 could inhibit the proliferation and metastasis of colon cancer through FOXM1 regulation of METTL3/YTHDF1.