However, to date, the underlying mechanism for the association of hsa-miR-337-3p with human gastric cancer metastasis is unknown. The hsa-miR-337-3p (miR-337) gene is localized at chromosome 14q32.2. In this chromosome locus, BCL11B may act as a tumor-suppressor gene in T-cell acute lymphoblastic leukemia [20, 21]. However, the relationship

between hsa-miR-337-3p and BCL11B and their AL3818 role in gastric cancer metastasis needs to be further determined. Only a few studies have described the role of hsa-miR-337-3p in human tumorigenesis. For example, a previous study has shown that hsa-miR-337-3p is highly expressed in immortalized fetal lung fibroblast IMR-90 cells and is detectable in immortalized find more human bronchial epithelial HBEC cells [22]. Another study has demonstrated that hsa-miR-337-3p is a modulator of cellular response to taxanes [22]. Furthermore, hsa-miR-337-3p was able to regulate the expression of STAT3 and RAP1A to mediate paclitaxel sensitivity [22]. Indeed, MNK inhibitor constitutive STAT3 activation is associated with various human cancers and commonly suggests poor prognosis [23, 24]. Previous studies have shown that RAP1A is an important player in adhesion

and migration of lymphocytes. Moreover, Rap GTPases are master regulators of integrin activation, cell motility, and the underlying cytoskeletal, adhesion, and membrane dynamics. Rap activation is critical for B-lymphoma cells Cediranib (AZD2171) to undergo transendothelial migration in vitro and in vivo[25]. In addition, altered expression of hsa-miR-337-3p may be critical in renal cell carcinoma (RCC) development, although the analysis of circulating serum levels of hsa-miR-337-3p is unlikely

to provide helpful diagnostic/prognostic information in RCC [26]. However, a previous study has reported that hsa-miR-337-3p is among 24 miRNAs that are significantly upregulated in gastric cancer compared to normal gastric mucosae [27], but that study did not specify how many cases were used in the miRNA array analysis and did not verify their results by qRT-PCR [16]. Thus, besides the technological reasons, the previous contradiction of hsa-miR-337-3p expression in gastric cancer can be explained by their different metastatic potentials accordingly to our current findings. Our current study demonstrated that hsa-miR-337-3p acted as a potential therapeutic agent for gastric cancer. For example, we may use a modified hsa-miR-337-3p oligonucleotide mimic to function as hsa-miR-337-3p to inhibit gastric cancer progression and metastasis. Conclusions Our current study demonstrated hsa-miR-337-3p downregulation in metastatic gastric cancer tissues and gastric cancer cell lines. Our in vitro study showed that restored hsa-miR-337-3p expression suppressed gastric cancer cell invasion, suggesting that hsa-miR-337-3p may be a potential therapeutic agent to inhibit gastric cancer metastasis.