The Methylation Of ZNF545 And Its Mechanism For Suppressive Effects On Cell Growth In Colorectal Cancer

Objective:The aim of the research is to detect the expression and methylation of ZNF545 in colorectal cancer(CRC)cells and CRC tissues,study the functions of ZNF545 on CRC cell proliferation,colony formation,apoptosis and cell cycle,and discuss the mechanism of ZNF545 for suppressing CRC cell preliminarily.Methods and results: 1.The expression of ZNF545 was detected by RT-PCR in CRC cell lines and the result showed that ZNF545 was down regulated or silenced.2.The expression of ZNF545 in 32 paired CRC tissues and adjacent tissues were detected by qPCR and the result showed that ZNF545 was down regulated in CRC tissues compared with adjacent tissues.3.The promoter methylation of ZNF545 in 32 cases of primary CRC tissues and 6 cases of normal colorectal tissues were detected by MSP,the result indicated that the methylation rate in CRC tissues was higher than that in normal tissues(p= 0.0116);the expression of ZNF545 was restored after demethylation treatment in CRC cell lines.4.After the plasmid pcDNA3.1 and pc DNA3.1-ZNF545 were transfected to SW480 and HT-29 cells,the functions of ZNF545 were detected by MTS,clone formation assay and flow cytometer.The results showed that ZNF545 inhibit CRC cell proliferation and colony-formation ability,induce cell apoptosis and G0/G1 cell cycle arrest;in vivo,ZNF545 inhibited xenograft growth of CRC tumors in nude mice.5.The mechanism of ZNF545 for suppressing CRC cell was tested by Western-blot assay,and the result showed that ZNF545 probably through Wnt/β-catenin and PI3K/AKT signaling pathways to influence the functions.Conclusion: In the colorectal cancer cells and tissues,the expression of ZNF545 are down-regulated for methylation;ZNF545 can inhibit proliferation and colony formation,induce apoptosis and G0/G1 cell cycle arrest,and suppress the growth of CRC cell in vivo,which indicate that ZNF545 is a suppressor gene.The gene of ZNF545 inhibits the CRC cell growth probably through Wnt/β-catenin and PI3K/AKT signaling pathways,which may be a promising marker and therapeutic target gene in CRC.