Identification of miR-515-3p and its targets, vimentin and MMP3, as a key regulatory mechanism in esophageal cancer metastasis: functional and clinical significance

Abstract

Metastasis is the main factor of treatment failure in cancer patients, but the underlying mechanism remains to be elucidated and effective new treatment strategies are urgently needed. This study aims to explore novel key metastasis-related microRNAs (miRNAs) in esophageal squamous cell carcinoma (ESCC). By comparing miRNA profiles of the highly metastatic ESCC cell sublines, we established through serial in vivo selection with the parental cells, we found that the expression level of miR-515-3p was lower in ESCC tumor tissues than adjacent normal tissues, further decreased in metastatic tumors, and moreover, markedly associated with advanced stage, metastasis and patient survival. The in vitro and in vivo assays suggested that miR-515-3p could increase the expression of the epithelial markers as well as decrease the expression of the mesenchymal markers, and more importantly, suppress invasion and metastasis of ESCC cells. Mechanistically, we revealed that miR-515-3p directly regulated vimentin and matrix metalloproteinase-3 (MMP3) expression by binding to the coding sequence and 3′untranslated region, respectively. In addition, the data from whole-genome methylation sequencing and methylation-specific PCR indicated that the CpG island within miR-515-3p promoter was markedly hypermethylated in ESCC cell lines and ESCC tumor tissues, which may lead to deregulation of miR-515-3p expression in ESCC. Furthermore, our preclinical experiment provides solid evidence that systemic delivery of miR-515-3p oligonucleotide obviously suppressed the metastasis of ESCC cells in nude mice. Taken together, this study demonstrates that miR-515-3p suppresses tumor metastasis and thus represents a promising prognostic biomarker and therapeutic strategy in ESCC.

Genome-wide identification of key regulatory lncRNAs in esophageal cancer metastasis

“…S1a ). 5 Next-generation sequencing of lncRNAs and miRNAs was carried out and our results suggested that the AC005562.1-hsa-miR-29c regulatory axis was significantly altered in invasive and metastatic cells, and the results were confirmed by qRT-PCR (Fig. 1a , Supplementary Fig.…”

Construction of a Prognostic Immune-Related LncRNA Risk Model for Lung Adenocarcinoma

“…miR-515-3p directly regulates MMP3 expression by binding to the coding sequence. MMP3 promotes tumor metastasis and thus represents a promising prognostic biomarker and therapeutic strategy in esophageal squamous cell carcinoma ( Hu et al, 2020 ). Rhabdomyosarcoma (RMS) is an aggressive pediatric malignancy of the muscle that includes fusion positive (FP)-RMS harboring PAX3/7-FOXO1 and fusion negative (FN)-RMS commonly with RAS pathway mutations.…”

Roles of microRNAs in tumorigenesis and metastasis of esophageal squamous cell carcinoma

“…Qi et al [ 73 ] showed that the miR-29b/MMP2 axis inhibited cell invasion in vitro , as well as tumor growth in an animal model, indicating its involvement in both tumor development and metastasis. Other members of the MMP protein family, such as MMP3, MMP13, and MMP14, were found to be regulated by miR-515-3p[ 74 ] , miR-375[ 75 ], and miR-133a[ 76 ], respectively.…”

“…Similarly, SMAD7 can be regulated by miR-424-5p[ 83 ] and miR-106b[ 84 ]. The miR-515-3p/vimentin regulatory axis can reverse EMT and negatively regulate ESCC metastasis[ 74 ]. Another miRNA that targets vimentin, namely, miR-146a, was also reported to suppress ESCC invasion by disrupting fibronectin membrane assembly[ 85 ].…”

“…Another miRNA, miR-27a, had similar tumor-suppressive effect on ESCC tumor growth in vivo after direct injection into implanted tumor[ 104 ]. Most recently, three miRNAs including miR-377, miR-29c, and miR-515-3p proved to have therapeutic potential through systemic delivery via intravenous injection in mouse models[ 38 , 40 , 74 ]. Specifically, systemically administered miR-377 was able to suppress the growth of subcutaneous ESCC tumor xenografts and lung metastasis in a mouse model[ 38 ].…”