The Metastasis-Associated microRNA miR-516a-3p Is a Novel Therapeutic Target for Inhibiting Peritoneal Dissemination of Human Scirrhous Gastric Cancer

Abstract

Although aberrant microRNA (miRNA) is expressed in different types of human cancer tissues, its pathophysiologic role and the relevance of tumorigenesis and metastasis are still largely unknown. Here, we defined miRNAs involved in cancer metastasis (metastamirs) using an established mouse model for peritoneal dissemination of human scirrhous gastric carcinoma cells. Highly metastatic derivatives (44As3 cells) were derived from the parental cells originally isolated from patients (HSC-44PE cells). Using microarray analysis to identify differentially expressed miRNAs in 44As3 and HSC-44PE cells, we focused on miR-516a-3p as a candidate antimetastatic miRNA (antimetastamir) whose functions in cancer had not been studied. We confirmed attenuated expression of miR-516a-3p in 44As3 cells compared with HSC-44PE cells by Northern blot analysis and quantitative reverse transcriptase PCR. Stable ectopic overexpression in 44As3-miR-516a-3p cells permitted identification of sulfatase 1 as a direct target of the miRNA, through use of the isobaric tagging reagent iTRAQ and the QSTAR Elite Hybrid LC-MS/MS system. Sulfatase 1 is known to remove 6-O-sulfates from heparan sulfate proteoglycans on the cell surface, causing release of membrane-bound Wnt ligands from cells. Consistent with this function, Western blot analyses revealed high levels of Wnt3a, Wnt5a, and nuclear b-catenin accumulation in 44As3 cells but relatively reduced levels in 44As3-miR-516a-3p cells. Notably, orthotopic inoculation of nude mice with 44As3-miR-516a-3p cells yielded significantly longer survival periods compared with mice inoculated with control 44As3 cells. Through atelocollagen-mediated delivery of an miR-516a-3p expression vector into orthotopic 44As3 tumors, we documented its feasibility as a treatment agent. Our findings define the miRNA miR-516-3p as an antimetastamir with potential therapeutic applications in blocking metastatic dissemination of gastric cancers. Cancer Res; 71(4); 1442-53. Ó2010 AACR.

MicroRNA-409 suppresses tumour cell invasion and metastasis by directly targeting radixin in gastric cancers

“…Recently, compelling evidence has shown that miRNAs exert significant impacts on the migration, invasion and metastasis of human cancers, and even demonstrates that miRNAs have the therapeutic potential. 34 However, only a few miRNAs (miR-218, 15 miR-516a-3p, 16 miR-107, 35 Let-7f 18 ) have been reported to be involved in the metastasis of GC. So identifying more miRNAs related to GC metastasis is important for clarifying the complicated mechanisms underlying GC metastasis.…”

“…11,12 Currently, many miRNAs are reported to be involved in proliferation, Helicobacter pylori infection, multidrug resistance, disease diagnosis and prognosis of GC. 13,14 However, only a few miRNAs, including miR-218, 15 miR516a-3p, 16 miR-107 17 and Let-7f, 18 are known to be involved in the metastasis of GC. These miRNAs may have the potential to act as either biomarkers or therapeutic targets for advanced GC.…”

Aberrant hypermethylation ofmiR-9genes in gastric cancer

“…Recent studies have indicated that several miRNAs, including miR-34b/c, miR-129, miR-137, miR-181C, miR-199a, miR-212, miR-512 and miR-516, were dysregulated and showed aberrant methylation patterns in gastric cancer cells. 6,9,[14][15][16][17][18][19][20][21] The three pri-miR-9 transcripts are all located within non-protein coding transcripts (Fig. 2A).…”

The microRNA miR-516a-3p regulates the Wnt pathway by targeting extracellular sulfatase 1 in human scirrhous gastric cancers: Anti-metastatic therapy via miRNA-based medicine

“…The results of an miRNA array among the above four lines showed that the miR-516a-3p levels were significantly lower in both of the metastatic lines than in their parent lines [12]. A stable line of 44As3 cells exhibiting ectopic overexpression of the miRNA miR-516a-3p (44As3-miR-516a-3p) exhibited decreased cell proliferation, migration, and invasion in vitro, and also decreased ascites fluid and peritoneal dissemination upon orthotopic inoculation into nude mice, when compared with an empty vector-inoculated group [12].…”

“…miRNAs exhibit differential expression in cancers and play important roles in their progression and metastasis [10,11]. Recently, we identified various miRNAs [12] associated with peritoneal dissemination using our orthotopic inoculation models [13,14]. In subsequent studies, we used our two established parent cell lines (HSC-44PE and HSC-58) from individual scirrhous gastric cancer patients [13], and further isolated two clones (44As3 and 58As9) with a highly metastatic character [14] from the corresponding parental cells.…”