MiR-375 suppresses the growth and metastasis of esophageal squamous cell carcinoma by targeting PRDX1.

Abstract

Esophageal cancer (EC) is one of the most lethal cancers. Esophageal squamous cell carcinoma (ESCC) is the most common histological subtype in Asian people. Diverse microRNAs, such as miR-375, have been confirmed to be involved in the process of tumorigenesis and metastasis. However, the underlying mechanism through which miR-375 acts in ESCC patients remains unknown. We used The Cancer Genome Atlas (TCGA) database to analyze the association between miR-375 and the survival rate in patients with esophageal squamous cell carcinoma. Real Time quantitative PCR (RT-qPCR) analysis was performed to evaluate the level of miR-375 in EC tissues and cells. A luciferase reporter assay was used to confirm the target gene of miR-375. A colony formation assay as well as flow cytometric and transwell invasion experiments were employed to examine the effects of miR-375 and peroxiredoxin 1 (PRDX1) on ESCC cells. A tumor xenograft mouse model was then used to investigate the role of miR-375 on tumor growth in vivo. Moreover, we performed rescue experiments to evaluate the effect of PRDX1 on ESCC progression. miR-375 expression was significantly downregulated in both ESCC clinical tissues and serum, and the reduction of miR-375 was remarkably linked to a poor prognosis in ESCC. Further investigation illustrated that aberrant expression of miR-375 dampened the growth and infiltration of ESCC cells both in vitro and in vivo. Bioinformatics and luciferase reporter analysis verified that the transcript of PRDX1 is a direct target of miR-375 and its expression in ESCC cells was found to be inversely modulated by miR-375. Moreover, the tumor formation experiment in nude mice confirmed that miR-375 can effectively dampen tumor growth in xenograft tumor mice models. Notably, over-expression of PRDX1 effectively counteracted the tumor-suppressing capabilities of miR-375. We demonstrated the antitumor effect of miR-375 on ESCC by targeting PRDX1 both in vitro and in vivo.