Long non-coding RNA XIST promotes the development of esophageal cancer by sponging miR-494 to regulate CDK6 expression

Abstract Objective Esophageal cancer is one of the deadliest cancers worldwide occurring at upper gastrointestinal tract. This study aimed to explore the possible role of long non-coding RNA X Inactive Specific Transcript (XIST) in the development of esophageal cancer. Material and methods The lncRNA XIST expressions both in esophageal cancer tissues and in cells were investigated. The TE-1 and SKGT-4 cells were transfected with LV-sh-XIST and LV-scramble for the further detection of the effects of XIST expression on cell biological processes, including proliferation, apoptosis and the expression of apoptosis-related proteins, migration, invasion and the expression of epithelial-mesenchymal transition markers. Additionally, the regulatory relationships between lncRNA XIST and miR-494, between miR-494 and CDK6, between miR-494/CDK6 and JAK2/STAT3 pathway were investigated. Results LncRNA XIST was overespressed in esophageal cancer tissues and cells. Suppression of XIST significantly inhibited the proliferation, migration and invasion, but induced apoptosis of two kinds of cells, TE-1 and SKGT-4. Moreover, miR-494 was down-regulated in esophageal cancer tissues and cells. XIST could sponge miR-494 and inhibition of miR-494 reversed the effects of XIST suppression on the malignant behaviors of TE-1 cells. Also, CDK6 was a target of miR-494 and CDK6 knockdown reversed the effects of miR-494 inhibition on the malignant behaviors of TE-1 cells. Besides, the expression of p-JAK2 and p-STAT3 was increased after miR-494 inhibition, which was reversed after inhibition of miR-494 and CDK6 at the same time. Conclusions The data presented in this study revealed that XIST abnormal expression may play an oncogenic role in the development of esophageal cancer via miR-494/CDK6 axis through JAK2/STAT3 signal pathway. This study may provide theoretical basis for the molecular mechanism investigation of esophageal cancer.