Expression and DNA Methylation Status of Long Non-coding RNA ZNF667-AS1 in Esophageal Squamous Cell Carcinoma Tissues

Objective To detect the expression and methylation status of long non-coding RNA ZNF667-AS1 in esophageal squamous cell carcinoma(ESCC) tissues.

Methods qPCR and MSP

Methods were respectively applied to detect the expression and methylation status of ZNF667-AS1 in esophageal cancer cell lines (Kyse170, Eca109, TE1, TE13), ESCC and corresponding noncancerous tissues before or after DNA methyltransferase inhibitor 5-Aza-dC treatment.

Results After treated with 5-Aza-dC, ZNF667-AS1 performed higher expression in the four esophageal cancer cell lines, and the methylation status of ZNF667-AS1 were decreased. The expression of ZNF667-AS1 in ESCC tissues was significantly lower than that in the corresponding normal tissues, and the methylation frequency of ZNF667-AS1 distal and exon1 regions CpG islands were all significantly different(P < 0.05). The methylation frequency of ZNF667-AS1 proximal promoter region CpG island in ESCC tissues was significantly higher than that in the corresponding normal tissues, and closely correlated with pathological differentiation and TNM stages; the methylation frequency in the low ZNF667-AS1 expression group was significantly higher than that in the high ZNF667-AS1 expression group.

Conclusion The low expression of ZNF667-AS1 is closely related to the occurrence and development of ESCC, and its proximal promoter region methylation may be one of the mechanisms of ZNF667-AS1 silence.