miR-922 regulates CYLD expression and promotes the cell proliferation of human hepatocellular carcinoma

MiR-182-5p Is Upregulated in Hepatic Tissues from a Diet-Induced NAFLD/NASH/HCC C57BL/6J Mouse Model and Modulates Cyld and Foxo1 Expression

Non-alcoholic fatty liver disease (NAFLD) is considered a relevant liver chronic disease. Variable percentages of NAFLD cases progress from steatosis to steatohepatitis (NASH), cirrhosis and, eventually, hepatocellular carcinoma (HCC). In this study, we aimed to deepen our understanding of expression levels and functional relationships between miR-182-5p and Cyld-Foxo1 in hepatic tissues from C57BL/6J mouse models of diet-induced NAFL/NASH/HCC progression. A miR-182-5p increase was detected early in livers as NAFLD damage progressed, and in tumors compared to peritumor normal tissues. An in vitro assay on HepG2 cells confirmed Cyld and Foxo1, both tumor-suppressor, as miR-182-5p target genes. According to miR-182-5p expression, decreased protein levels were observed in tumors compared to peritumor tissues. Analysis of miR-182-5p, Cyld and Foxo1 expression levels, based on datasets from human HCC samples, showed results consistent with those from our mouse models, and also highlighted the ability of miR-182-5p to distinguish between normal and tumor tissues (AUC 0.83). Overall, this study shows, for the first time, miR-182-5p overexpression and Cyld-Foxo1 downregulation in hepatic tissues and tumors from a diet-induced NAFLD/HCC mouse model. These data were confirmed by the analysis of datasets from human HCC samples, highlighting miR-182-5p diagnostic accuracy and demonstrating the need for further studies to assess its potential role as a biomarker or therapeutic target.

SOX4 induces drug resistance of colorectal cancer cells by downregulating CYLD through transcriptional activation of microRNA-17

Exposure to high doses of anticancer drugs can induce the emergence of a subpopulation of weakly proliferative and drug-tolerant cells. Drug tolerance can reduce the benefits obtained from canonical treatment and reduce the survival rate of patients. Regulation of SRY-related HMG box transcription factor 4 (SOX4) has been proved to affect drug sensitivity. The current study aimed to explore the role of SOX4 in drug resistance of colorectal cancer (CRC) cells as well as the related molecular mechanisms. Expression patterns of SOX4, microRNA-17 (miR-17), and CYLD in both CRC tissues and cells were determined with their relationship analyzed by bioinformatics analysis, dual-luciferase reporter gene assay, and ChIP. Loss- and gain-function assays were performed to ascertain the effect of SOX4, miR-17, and CYLD on biological cellular processes and drug resistance to 5-FU. SOX4 and miR-17 were found to be highly expressed while CYLD was poorly expressed in CRC tissues and cells. Silencing of SOX4 resulted in the suppression of cellular proliferation, invasion, migration as well as a reduction in CRC drug resistance. Mechanically, CYLD was specifically targeted by miR-17, while SOX4 upregulated the expression of miR-17. Functionally, SOX4 triggered drug resistance of CRC cells to 5-FU through the miR-17/CYLD axis. Taken together, the key findings of the present study provides evidence suggesting that SOX4 elevates miR-17 to decrease CYLD, thus inducing chemotherapy resistance of CRC cells.

CREB1 acts via the miR‑922/ARID2 axis to enhance malignant behavior of liver cancer cells

There is little information on the role of microRNA (miR)‑922 in the malignant behavior of liver cancer. The present study investigated the regulation of miR‑922 expression levels by cAMP response element binding protein 1 (CREB1) in liver cancer tissue, its role in regulating malignant behavior and its potential targets in liver cancer. miR‑922 expression in liver cancer cells and tissue was determined by reverse transcription‑quantitative PCR. The binding of CREB1 to the promoter region of mir‑922 was tested by chromatin immunoprecipitation‑PCR. The predicted AT‑rich interactive domain 2 (ARID2) and fidgetin, microtubule severing factor targets of miR‑922 were characterized by dual luciferase reporter assay. The effects of altered ARID2 expression levels on miR‑922‑enhanced malignant behavior of liver cancer cells were tested. CREB1 bound to the promoter region of miR‑922. Elevated miR‑922 transcripts were inversely associated with ARID2 expression in liver cancer tissue and cells. miR‑922 inhibited ARID2‑regulated luciferase expression and was present in the miR/argonaute RISC catalytic component 2 complex. ARID2 significantly decreased malignant behavior of liver cancer MHCC97L cells. Similarly, ARID2 over‑expression inhibited growth of xenograft liver cancer tumors and decreased miR‑922, Bcl‑2, proliferating cell nuclear antigen, cyclin D1, MMP3 and MMP9 expression and serum VEGF and TNF‑α levels, but enhanced Bax expression levels in tumors. ARID2 over‑expression abrogated malignant behavior promoted by miR‑922 over‑expression and enhanced miR‑922‑decreased malignant behavior of liver cancer cells. CREB induced miR‑922 transcription, which targeted ARID2 to enhance malignant behavior of liver cancer cells, indicating that the CREB1/miR‑922/ARID2 axis may be a potential target for liver cancer treatment.

Anti-oncogenic effects of SOX2 silencing on hepatocellular carcinoma achieved by upregulating miR-222-5p-dependent CYLD via the long noncoding RNA CCAT1

In this study, we determined the involvement of SOX2 and its downstream signaling molecules in hepatocellular carcinoma (HCC) progression. We carried out lentiviral transfection in HepG2 cells to determine the roles of SOX2, CCAT1, EGFR, miR-222-5p, and CYLD in HepG2 cells. We first determined the interaction between SOX2 and CCAT1 and that between miR-222-5p and CYLD and their effect on tumor growth in vivo was analyzed in HCC-xenograft bearing nude mice xenografts. SOX2 and CCAT1 were highly expressed in HCC tissues and HepG2 cells. SOX2 bound to the regulatory site of CCAT1. Silencing of SOX2 or CCAT1 inhibited HepG2 cell proliferation, migration, and invasion as well as decreased the expression of CCAT1 and EGFR. CCAT1 silencing reduced EGFR expression, but EGFR expression was increased in HCC tissues and HepG2 cells, which promoted proliferation, migration, and invasion in vitro. EGFR upregulated miR-222-5p, leading to downregulation of CYLD. miR-222-5p inhibition or CYLD overexpression repressed cell functions in HepG2 cells. SOX2 silencing decreased CCAT1, EGFR, and miR-222-5p expression but increased CYLD expression. Loss of SOX2 also reduced the growth rate of tumor xenografts. In summary, SOX2-mediated HCC progression through an axis involving CCAT1, EGFR, and miR-222-5p upregulation and CYLD downregulation.

Maternally expressed 3 protects the intestinal barrier from cardiac arrest-induced ischemia/reperfusion injury via miR-34a-3p/sirtuin 1/nuclear factor kappa B signaling

BACKGROUND

Cardiac arrest (CA), a common disease with a high mortality rate, is a leading cause of ischemia/reperfusion (I/R)-induced dysfunction of the intestinal barrier. Long non-coding RNAs (lncRNAs) play crucial roles in multiple pathological processes. However, the effect of the lncRNA maternally expressed 3 (MEG3) on intestinal I/R injury and the intestinal barrier has not been fully determined. Therefore, this study aimed to investigate the function of MEG3 in CA-induced intestinal barrier dysfunction.

METHODS

The oxygen and glucose deprivation (OGD) model in the human colorectal adenocarcinoma Caco-2 cells and in vivo cardiac arrest-induced intestinal barrier dysfunction model in Sprague-Dawley (SD) rats were established. The effect and underlying mechanism of MEG3 on the intestinal barrier from cardiac arrest-induced ischemia/reperfusion injury were analyzed by methyl thiazolyl tetrazolium (MTT) assays, Annexin V-FITC/PI apoptosis detection kit, Terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) staining, quantitative polymerase chain reaction (qPCR) assays, Western blot analysis, luciferase reporter gene assays, transepithelial electrical resistance (TEER) measurements, immunofluorescence analysis, and enzyme-linked immunosorbent assay (ELISA) assays.

RESULTS

Interestingly, we found that MEG3 could protect Caco-2 cells from oxygen-glucose deprivation (OGD)/reoxygenation-induced I/R injury by modulating cell proliferation and apoptosis. Moreover, MEG3 relieved OGD-induced intestinal barrier dysfunction in vitro, as demonstrated by its significant rescue effect on transepithelial electrical resistance and the expression of tight junction proteins such as occludin and claudin-1 (CLDN1), which were impaired in OGD-treated Caco-2 cells. Mechanistically, MEG3 inhibited the expression of inflammatory factors including interleukin (IL)-1β, tumor necrosis factor (TNF)-α, interferon-gamma (IFN)-γ, inflammatory factors including interleukin (IL)-10, and transforming growth factor beta (TGFb)-1, as well as nuclear factor-kappa B (NF-κB) signaling. In response to OGD treatment in vitro, MEG3 also activated the expression of sirtuin 1 (SIRT1) by Caco-2 cells via sponging miR-34a-3p. Furthermore, MEG3 relieved CA-induced intestinal barrier dysfunction through NF-κB signaling in vivo.

CONCLUSIONS

LncRNA MEG3 can protect the intestinal barrier from cardiac arrest-induced I/R injury via miR-34a-3p/SIRT1/NF-κB signaling. This finding provides new insight into the mechanism by which MEG3 restores intestinal barrier function following I/R injury, presenting it as a potential therapeutic candidate or strategy in intestinal injury.

Six Candidate miRNAs Associated With Early Relapse in Pediatric B-Cell Acute Lymphoblastic Leukemia

BACKGROUND/AIM

Few studies have evaluated the role of miRNAs in pediatric acute lymphoblastic leukemia (ALL) relapse and a consensus of a clinically significant miRNA signature is yet to be identified. In this study, we evaluated miRNAs associated with pediatric B-ALL early relapse in two independent sample sets.

MATERIALS AND METHODS

We performed global miRNA profiling on diagnostic bone marrow specimens from six early relapse (≤3 years after diagnosis) and six age- and cytogenetics-matched prolonged remission (≥4 years) patients (first set) and an independent set of 14 early relapse and 14 matched prolonged remission specimens (second set).

RESULTS

Twelve and 39 top differentially expressed miRNAs were observed in the first and second sets, respectively; however, there was no overlap between the top candidates. In post-hoc analyses six miRNAs (miR-101-3p, miR-4774-5p, miR-1324, miR-631, miR-4699-5p and miR-922) among the top candidates in the second, but not the first set, were consistently upregulated in early relapse compared to remission specimens in both first (fold change=1.13-2.19, q<0.38) and second (fold change=1.48-4.78, all q<0.05) sets. Four (miR-631, mir-101-3p, miR-922 and miR-1324) of these miRNAs have been previously implicated in key functional oncogenic pathways in adult cancers.

CONCLUSION

This study suggests that six candidate miRNAs, not previously implicated in pediatric ALL, are associated with early relapse in pediatric B-ALL. Validation and investigation of mechanistic roles of these miRNAs in a larger cohort are warranted, so that they may be used as prognostic markers for early relapse of pediatric B-ALL.

CCHE1 accelerated the initiation of oral squamous cell carcinoma through enhancing PAK2 expression by sponging miR-922

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a normal form of mouth cancer, comprising the majority of oral cancers. A large number of long non-coding RNAs (lncRNAs) have been reported due to their oncogenic function in cancers. Recent studies show that lncRNA CCHE1 is an oncogene in a wide range of cancers. Whether CCHE1 accelerates the progression of OSCC is still undiscovered.

METHODS

The qRT-PCR analysis was used to determine CCHE1, miR-922, and PAK2 expression levels. CCK8 and colony formation assays were applied to evaluate OSCC cell proliferative ability. Transwell assay was performed to investigate the capability of cell migration and invasion. Cell apoptosis was assessed by flow cytometry analysis. The distribution of CCHE1 in OSCC cells was confirmed via subcellular fractionation assay. Luciferase reporter assay was used to verify the connection between miR-922 and CCHE1 or PAK2.

RESULTS

qRT-PCR analysis identified the upregulation of CCHE1 in OSCC cells. Knockdown of CCHE1 curbed the proliferation, migration, and invasion and hastened the apoptosis in OSCC cell lines. Moreover, it was found that miR-922 could interact with CCHE1. Besides, PAK2 was identified as the target gene of miR-922 and its expression was negatively modulated by miR-922 and positively regulated by CCHE1. Restoration assay manifested that the suppressing influence of CCHE1 depletion on OSCC progression was rescued by amplified PAK2.

CONCLUSIONS

CCHE1 increases the expression of PAK2 to promote the progression of OSCC by competitively binding to miR-922 in OSCC cells.

miR-922 regulates apoptosis, migration, and invasion by targeting SOCS1 in gastric cancer

Gastric cancer (GC) is the second leading cause of cancer-related death worldwide. Studies have shown that miR-922 facilitates the development of various diseases and tumors. However, the role of miR-922 in GC and related molecular mechanisms are still unrevealed. Current study indicated that miR-922 was overexpressed in GC tissues and cells. The survival rate of patients in high miR-922 expression group is significantly lower than that in low miR-922 expression group. In addition, overexpression of miR-922 observably restrained the apoptosis of SGC7901 cells and promoted SGC7901 cell proliferation, migration, and invasion. TargetScan predicted that suppressors of cytokine signaling 1 (SOCS1) was a potential target of miR-922. miR-922 upregulation profoundly inhibited the expression of SOCS1. Furthermore, the mRNA level of SOCS1 in GC tissues was significantly lower than that in adjacent tissues, indicating that miR-922 promoted the proliferation, invasion, and migration, and inhibited apoptosis of SGC7901 cells by downregulating the level of SOCS1. In conclusion, miR-922 may have potential for diagnosis of GC.

A detailed image of rutin underlying intracellular signaling pathways in human SW480 colorectal cancer cells based on miRNAs-lncRNAs-mRNAs-TFs interactions

Natural dietary ingredients like flavonoids are important for body improvement against diseases. The flavonol rutin is widely found in fruits and vegetables and shows significant anticancer properties. However, the underlined signaling pathways have not been elucidated yet. In this study, the impacts of various doses of rutin (400-700 mM/ml) have been examined on human colon cancer SW480 cells metabolism, cell cycle, and apoptosis. The transcriptome was analyzed by bioinformatics tools and the interactions between rutin modulated microRNAs (miRNAs), long noncoding RNAs (lncRNAs), messenger RNAs (mRNAs), and transcription factors (TFs) were built, filtered and enriched. A dose of 600 mM of rutin significantly decreased cells metabolic activity, halved the population and arrested the cell cycle at the sub-G1 phase. The enrichment analysis of miRNAs-lncRNAs-mRNAs-TFs network showed that these effects were mediated through alteration of glucose, lipid, and protein metabolism, modulating endoplasmic reticulum stress responses, negative regulation of cell cycle process, and inducing the extrinsic and intrinsic apoptotic signaling pathways. Additionally, the key parent nodes of each annotation were illustrated. These findings create a detailed image of rutin underlying intracellular signaling pathways in CRC and also help us to better understand the role of dietary natural compounds in cancer treatment.

eNOS expression and NO release during hypoxia is inhibited by miR-200b in human endothelial cells

The nitric oxide (NO) secreted by vascular endothelium is required for the maintenance of cardiovascular homeostasis. Diminished release of NO generated by endothelial NO synthase contributes to endothelial dysfunction. Hypoxia and ischemia reduce endothelial eNOS expression via posttranscriptional mechanisms that result in NOS3 transcript destabilization. Here, we examine whether microRNAs contribute to this mechanism. We followed the kinetics of hypoxia-induced changes in NOS3 mRNA and eNOS protein levels in primary human umbilical vein endothelial cells (HUVECs). Utilizing in silico predictive protocols to identify potential miRNAs that regulate eNOS expression, we identified miR-200b as a candidate. We established the functional miR-200b target sequence within the NOS3 3′UTR, and demonstrated that manipulation of the miRNA levels during hypoxia using miR-200b mimics and antagomirs regulates eNOS levels, and established that miR-200b physiologically limits eNOS expression during hypoxia. Furthermore, we demonstrated that the specific ablation of the hypoxic induction of miR-200b in HUVECs restored eNOS-driven hypoxic NO release to the normoxic levels. To determine whether miR-200b might be the only miRNA that had this effect, we utilized Next Generation Sequencing (NGS) to follow hypoxia-induced changes in the miRNA levels in HUVECS and found 83 novel hypoxamiRs, with two candidate miRNAs besides miR-200b that could potentially influence eNOS levels. Taken together, the data establish miR-200b-eNOS regulation as a first hypoxamiR-based mechanism that limits NO bioavailability during hypoxia in endothelial cells, and show that hypoxamiRs could become useful therapeutic targets for cardiovascular diseases and other hypoxic-related diseases including various types of cancer.