Analysis Of The Status Of PLCE1 Gene Promoter Methylation In Kazakh Escc And The Clinical Significance Of The PLCE1 Gene Promoter Methylation

Object: To explore the relationship between the methylation status of PLCE1 gene promoter and the expression of protein and clinicopathological features.Detecting the methylation status of PLCE1 gene promoter in four kinds of esophageal squamous cell cancer cells with 5-aza-d C treatment or not and finding its connection with protein expression.Exploring the effects on invasion and apoptosis of ESCC cells after treating with the PLC inhibitor-U73122.Methods: 51 cases of ESCC from Kazakh nationality were collected.The protein expression was examined by Envision-IHC.And the methylation status was detected by methylation specific PCR(MSP).The invasion ability was detected by Transwell invasion assay.Cell apoptosis was detected by flow cytometry and TUNEL staining.And we used we used Western blot to detect the protein expression of PLCE1 and markers of epithelial mesenchymal transition and apoptosis.Results:(1)The protein expression of PLCE1 in Xinjiang Kazakh esophageal squamous cell cancer was significantly higher than that of normal tissues.And the methylation rate of PLCE1 gene promoter was significantly lower than that in the normal group,there was significant difference between the two groups(P < 0.001).In Xinjiang Kazakh ESCC tissues,the promoter methylation levels were much lower in high PLCE1 protein expression tissues than in low PLCE1 protein expression tissues.There was significant difference between the two groups(P=0.028).The promoter methylation level had no relationship with gender and age of patients,and tumor size and postoperative survival time.It was correlated with lymph node and distant metastasis(?2=7.242,P=0.027)and TNM stage(?2=7.883,P=0.019).(2)The promoter methylation levels of PLCE1 in esophageal cancer cell line Eca109,TE-1,EC9706,Kyse150 and the PLCE1 protein expression was inversely proportional.5-aza-d C decreased the methylation of PLCE1 but increased the protein expression of TE-1 and Kyse150 cell lines.(3)U73122,the PLC inhibitor,inhibited PLCE1 significantly at the density of 10 u M after treating ESCC cells 48 hours.Transwell invasion assayproved that 73122 weakened the cell invasion.The epithelial marker E-cadherin increased while the mesenchymal marker Vimentin decreased after U73122 treated.The flow cytometry and TUNEL staining showed that the number of apoptosis cells was increased.And the apoptotic molecules,Bax,Cleaved-PARP,Caspase3 and Caspase7 was up regulated,and the anti apoptotic protein Bcl-2 was down regulated.Conclusion: Demethylation of PLCE1 gene leads to high protein expression in esophageal squamous cell carcinoma,which promotes the malignant biological behavior of esophageal cancer cells.