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Various miRNAs have been shown to participate in the tumor progression and development of colorectal cancer (CRC). However, the role of miR-3913-5p in CRC are yet to be clearly defined. In the present study, we determine that miR-3913-5p is downregulated in CRC cell lines and CRC tissues. Exogenous miR-3913-5p expression weakens the CRC cells growth, migration and invasion. Mechanistically, miR-3913-5p directly targets the 3'UTR of CREB5. Overexpression of CREB5 reverses the suppression of CRC cells proliferation, migration and invasion induced by miR-3913-5p. Furthermore, ATF2 negatively regulates the transcription of miR-3913-5p by binding to its promoter. CREB5 can cooperate with ATF2. CREB5 is required for ATF2 in regulating miR-3913-5p. Finally, inverse correlations can be found between the expressions of miR-3913-5p and CREB5 or ATF2 in CRC tissues. Thus, a plausible mechanism of ATF2/miR-3913-5p/CREB5 axis regulating CRC progression is elucidated. Our findings suggest that miR-3913-5p functions as a tumor suppressor in CRC. ATF2/miR-3913-5p/CREB5 axis might be a potential therapeutic target against CRC progression. The miRNA miR-3913-5p inhibits colorectal cancer cell proliferation, migration and invasion, in concert with its regulation of and by CREB5 and ATF2. [ABSTRACT FROM AUTHOR]

Purpose: Growing evidence indicates that aberrant expression of microRNAs contributes to tumor development. However, the biological role of microRNA-4490 (miR-4490) in gastric cancer (GC) remains to be clarified. Methods: To explore the function of miR-4490 in GC, we performed colony formation, EdU incorporation, qRT-PCR, Western blotting, in situ hybridization (ISH), immunohistochemistry (IHC), flow cytometry, ChIP and dual-luciferase reporter assays. In addition, the growth, migration and invasion capacities of GC cells were evaluated. Results: We found that miR-4490 was significantly downregulated in primary GC samples and in GC-derived cell lines compared with normal controls, and that this expression level was negatively correlated with GC malignancy. Exogenous miR-4490 expression not only reduced cell cycle progression and proliferation, but also significantly inhibited GC cell migration, invasion and epithelial-mesenchymal transition (EMT) in vitro. Mechanistically, we found that miR-4490 directly targets USP22, which mediates inhibition of GC cell proliferation and EMT-induced metastasis in vitro and in vivo. Moreover, we found through luciferase and ChIP assays that transcription factor POU2F1 can directly bind to POU2F1 binding sites within the miR-4490 and USP22 promoters and, by doing so, modulate their transcription. Spearman's correlation analysis revealed a positive correlation between USP22 and POU2F1 expression and negative correlations between miR-4490 and USP22 as well as miR-4490 and POU2F1 expression in primary GC tissues. Conclusion: Based on our results we conclude that miR-4490 acts as a tumor suppressor, and that the POU2F1/miR-4490/USP22 axis plays an important role in the regulation of growth, invasion and EMT of GC cells. [ABSTRACT FROM AUTHOR]

In human gastric cancer (GC), the upregulation of FOXK1 and vimentin is frequently observed in cancer cells and correlates with increased malignancy. We report that FOXK1 synergizes with vimentin to promote GC invasion and metastasis via the induction of epithelial-mesenchymal transition (EMT). We showed that higher expression levels of FOXK1 were significantly associated with GC development. FOXK1 can physically interact with and stabilize vimentin. Moreover, a positive correlation between the expression of FOXK1 and vimentin was found in GC cells. Higher expression levels of these two proteins were significantly associated with differentiation, lymph node metastasis, AJCC stage, and poorer prognosis. Furthermore, the coexpression of FOXK1 and vimentin enhances cell metastasis through the induction of EMT in GC cells. However, the siRNA-mediated repression of vimentin in FOXK1-overexpressing cells reversed the EMT-like phenotype and reduced GC cell migration and invasion in vitro and in vivo. Altogether, our findings suggest that the vimentin-FOXK1 axis provides new insights into the molecular mechanisms underlying EMT regulation during GC progression and metastasis. [ABSTRACT FROM AUTHOR]

The Editors-in-Chief therefore consider the data reported in this the article to be unreliable. Figure 4f: the AGS and BGC-823 panels for miR-4490/USP22 appear to partially overlap. [Extracted from the article]