LAUSR

Introduction Cysteine Protease Inhibitor 1 (CST1), a cystatin superfamily protein with the effect on the inhibition of cysteine protease activity, is reported to be involved in the development of many malignancies. MiR-942-5p has been demonstrated its regulatory effects on some malignancies. However, the roles of CST1 and miR-942-5p on esophageal squamous cell carcinoma (ESCC) are still unknown up to now. Methods The expression of CST1 in ESCC tissues was analyzed by TCGA database, immunohistochemistry, and RT-qPCR, respectively. Matrigel-uncoated or-coated transwell assay was used to determine the effect of CST1 on migration and invasion of ESCC cells. Regulatory effect of miR-942-5p on CST1 was detected by dual luciferase assay. Results CST1 was ectopically highly expressed in ESCC tissues, and had the effect on promoting the migration and invasion of ESCC cells by upregulating phosphorylated levels of key effectors including MEK1/2, ERK1/2, and CREB in MEK/ERK/CREB pathway. Dual-luciferase assay results showed that miR-942-5p had a regulatory effect on targeting CST1. Conclusions CST1 plays a carcinogenic role on ESCC, and miR-942-5p can regulate the migration and invasion of ESCC cells by targeting CST1 to downregulate MEK/ERK/CREB signaling pathway, suggesting that miR-942-5p/CST1 axis might be a promising target for diagnosis and treatment of ESCC.