Tumor suppressive microRNA‑429 regulates cellular function by targeting VEGF in clear cell renal cell carcinoma

Non-coding RNA and gene expression analyses of papillary renal neoplasm with reverse polarity (PRNRP) reveal distinct pathological mechanisms from other renal neoplasms

Papillary renal neoplasm with reversed polarity (PRNRP) is a recently described rare renal neoplasm. Traditionally, it was considered a variant of papillary renal cell carcinoma (PRCC). However, several studies reported significant differences between PRNRP and PRCC in terms of clinical, morphological, immunohistochemical and molecular features. Nonetheless, PRNRP remains a poorly understood entity. We used microarray analysis to elucidate the non-coding RNA (ncRNA) and gene expression profiles of 10 PRNRP cases and compared them with other renal neoplasms. Unsupervised cluster analysis showed that PRNRP had distinct expression profiles from either clear cell renal cell carcinoma (ccRCC) or PRCC cases at the level of ncRNA but were less distinct at the level of gene expression. An integrated omic approach determined miRNA:gene interactions that distinguished PRNRP from PRCC and we validated 10 differentially expressed miRNAs and six genes by quantitative RT-PCR. We found that levels of the miRNAs, miR-148a, miR-375 and miR-429, were up-regulated in PRNRP cases compared to ccRCC and PRCC. miRNA target genes, including KRAS and VEGFA oncogenes, and CXCL8, which regulates VEGFA, were also differentially expressed between renal neoplasms. Gene set enrichment analysis (GSEA) determined different activation of metabolic pathways between PRNRP and PRCC cases. Overall, this study is by far the largest molecular study of PRNRP cases and the first to investigate either ncRNA expression or their gene expression by microarray assays.

Estradiol mediates the interaction of LINC01541 and miR-429 to promote angiogenesis of G1/G2 endometrioid adenocarcinoma in-vitro: A pilot study

Background

Endometrioid adenocarcinoma (EAC) is the most common subtype of endometrial cancer (EC) and is an estrogen-related cancer. In this study, we sought to investigate the expressions and mechanism of action of 17β-estradiol (E2) and long noncoding RNA (lncRNA) LINC01541 in G1/G2 EAC samples.

Methods

The expressions of estrogen receptor β (ESR2), LINC01541, miR-200s, and VEGFA were evaluated using real-time PCR in human EAC tissues (n = 8) and adjacent normal tissues (n = 8). Two EC cell lines (Ishikawa and RL95-2) were selected for validation in vitro. Bioinformatics analyses and luciferase reporter analyses were performed to verify potential binding sites. qRT-PCR, Western blot, and CCK-8 were used to identify the regulatory mechanisms of related genes in cell biological behavior.

Results

Compared with adjacent normal tissues, LINC01541 and miR-200s family (except miR-200c) were highly expressed in EAC tissues (n=8), while ESR2 and VEGFA were lowly expressed in EAC tissues (* P < 0.05; ** P < 0.01). In vitro: E2 inhibited the expression of LINC01541 and miR-429 in both cell lines, and estrogen antagonist (PHTPP) could reverse this effect, in addition, PHTPP could promote the proliferation of these two cancer cells, cell transfection LINC01541 also had this effect after overexpression of plasmid and miR-429 mimic. E2 promotes the expression of VEGFA in both cell lines, and PHTPP can also reverse this effect. LINC01541 interacts with miR-429 to promote the expression of each other, and both inhibit the synthesis of VEGFA in EAC cells after overexpression. Through the double validation of bioinformatics analysis and dual fluorescein reporter gene, it was confirmed that miR-429 targets the regulation of VEGFA expression (* P < 0.05; ** P < 0.01).

Conclusion

E2 promotes the synthesis of VEGFA by altering the expression levels of LINC01541 and miR-429 in EAC, thereby affecting the angiogenesis process of EAC. Also, E2-mediated LINC01541/miR-429 expression may affect cell migration in EAC. In addition, we identified a reciprocal promotion between LINC01541 and miR-429.

Low expression of miR-138 inhibit the proliferation, migration and invasion of colorectal cancer and affect patient survival by targeting SIRT1

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers in the world, resulting in about 600,000 deaths every year. It is urgent to explore the molecular mechanism and find new effective therapy. Abnormal molecular expression in cancer is considered as a screening biomarker and therapeutic target for tumors, MicroRNA (miRNA) as one of the important molecules, plays an important role in the regulation of tumorigenesis.

METHODS

In this study, we aimed to elucidate the molecular mechanism by which mir-138 regulates the development and progression of CRC, and to find new molecular targets for the diagnosis and therapy of CRC. We have used qRT-PCR to study the expression of miR-138 and SIRT1 in CRC cells and tissues, CCK8 assay was used to test the proliferation ability of CRC cells, and invasion and migration ability of CRC cells in vitro were studied by Transwell assay.

RESULTS

We found that miR-138 was significantly decreased in CRC tissues and cell lines by qRT-PCR, the level of miR-138 was significantly correlated with lymph node metastasis and distant metastasis, the CRC patients with high miR-138 level whose overall survival and disease-free survival were significantly longer. We also found that the level of SIRT1 in CRC tissues and cell lines is higher, and through Dual-luciferase reporter assay, we found that SIRT1 is a new target of miR-138 in CRC, and SIRT1 knockdown could inhibit CRC proliferation, migration and invasion in vitro.

CONCLUSIONS

Thus, we found that miR-138 could inhibit CRC cell proliferation, migration and invasion by targeting SIRT1 firstly, and that will provide a new idea for the therapy of CRC.

Bioinformatic gene analysis for possible biomarkers and therapeutic targets of hypertension-related renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is one of the most prevalent malignant tumors of the urinary system. Hypertension can cause hypertensive nephropathy (HN). Meanwhile, Hypertension is considered to be related to kidney cancer. We analyzed co-expressed genes to find out the relationship between hypertension and RCC and show possible biomarkers and novel therapeutic targets of hypertension-related RCC.

METHODS

We identified the differentially expressed genes (DEGs) of HN and RCC through analyzing Gene Expression Omnibus (GEO) datasets GSE99339, GSE99325, GSE53757 and GSE15641 by means of bioinformatics analysis, respectively. Then we evaluated these genes with protein-protein interaction (PPI) networks, Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and CTD database. Subsequently, we verified co-expressed DEGs with Gene Expression Profiling Interactive Analysis (GEPIA) database. Finally, corresponding predicted miRNAs of co-expressed DEGs were identified and verified via mirDIP database and Starbase, respectively.

RESULTS

We identified 9 co-expressed DEGs, including BCAT1, CORO1A, CRIP1, ESRRG, FN1, LYZ, PYCARD, SAP30, and PTRF. CRIP1 and ESRRG and their corresponding predicted miRNAs, especially hsa-miR-221-5p, hsa-miR-205-5p, hsa-miR-152-3p and hsa-miR-137 may be notably related to hypertension-related RCC.

CONCLUSIONS

CRIP1 and ESRRG genes have great potential to become novel biomarkers and therapeutic targets concerning hypertension-related RCC.

[Inhibitory effect of miR-429 on expressions of ZO-1, Occludin, and Claudin-5 proteins to improve the permeability of blood spinal cord barrier in vitro]

OBJECTIVE

To explore the feasibility and mechanism of inhibiting miR-429 to improve the permeability of the blood spinal cord barrier (BSCB) in vitro, and provide a new gene therapy target for enhancing the spinal cord microenvironment.

METHODS

First, the immortalized human brain microvascular endothelial cell line (hCMEC/D3) was transfected with the anti-miR-429 antagonist (antagomiR-429) and its negative control (antagomiR-429-NC), respectively. The miR-429 expression of hCMEC/D3 cells was observed by fluorescence microscopy and real-time fluorescence quantitative PCR to verify the transfection efficiency of antagomiR-429. Then the effect of miR-429 on BSCB permeability was observed in vitro. The experiment was divided into 4 groups. The blank control group (group A) was constructed of normal hCMEC/D3 cells and Ha-sc cells to prepare the BSCB model, the hypoxia-induced group (group B), the hypoxia-induced+antagomiR-429-NC group (group C), and the hypoxia-induced+antagomiR-429 group (group D) were constructed of normal, antagomiR-429-NC transfected, and antagomiR-429 transfected hCMEC/D3 cells and Ha-sc cells to prepare the BSCB models and hypoxia treatment for 12 hours. The permeability of BSCB in vitro was measured by horseradish peroxidase (HRP) permeability. Real-time fluorescence quantitative PCR, Western blot, and immunofluorescence staining were used to observe the expressions of ZO-1, Occludin, and Claudin-5.

RESULTS

The antagomiR-429 and antagomiR-429-NC were successfully transfected into hCMEC/D3 cells under a fluorescence microscope, and the transfection efficiency was about 90%. Real-time fluorescence quantitative PCR results showed that the relative expression of miR-429 in antagomiR-429 group was 0.109±0.013, which was significantly lower than that of antagomiR-429-NC group (0.956±0.004, P<0.05). HRP permeability measurement, real-time fluorescence quantitative PCR, and Western blot results showed that the HRP permeability of groups B and C were significantly higher than those of groups A and D ( P<0.05), and the relative expressions of ZO-1, Occludin, and Claudin-5 proteins and mRNAs were significantly lower in groups B and C than in groups A and D ( P<0.05) and in group D than in group A ( P<0.05); there was no significant difference between groups B and C ( P>0.05). Immunofluorescence staining showed that the immunofluorescence of ZO-1, Occudin, and Claudin-5 at the cell membrane boundary in group D were stronger than those in groups B and C, but not as strong as that in group A.

CONCLUSION

Inhibition of miR-429 expression can promote the expressions of ZO-1, Occludin, and Claudin-5 proteins in microvascular endothelial cells, thereby improving the increased permeability of BSCB due to hypoxia.

miR-429-CRKL axis regulates clear cell renal cell carcinoma malignant progression through SOS1/MEK/ERK/MMP2/MMP9 pathway

The pathogenesis and tumorigenesis of clear cell renal cell carcinoma (ccRCC) remain unclear. The deregulations of miR-429, a member of miR-200 family, and v-crk sarcoma virus CT10 oncogene homologue (avian)-like (CRKL), an adaptor protein of CRK family, are involved in the development, metastasis and prognosis of various cancers. Current study aimed to demonstrate the differential expressions of miR-429 and CRKL with their correlationship and molecular regulation mechanism in ccRCC malignancy. miR-429 and CRKL separately showed suppressing and promoting effects in ccRCC. Lower miR-429 expression and higher CRKL expression were negatively correlated in surgical cancerous tissues by promoting the advance of ccRCC. By binding to the 3'-UTR of CRKL, miR-429 reversely regulated CRKL for its functionalities in ccRCC cells. CRKL knockdown and overexpression separately decreased and increased the in vitro migration and invasion of 786-O cells, which were consistent with the influences of miR-429 overexpression and knockdown on 786-O through respectively downregulating and upregulating CRKL via SOS1/MEK/ERK/MMP2/MMP9 pathway. The enhancements of CRKL expression, migration and invasion abilities and SOS1/MEK/ ERK/MMP2/MMP9 activation induced by TGF-β stimulation in 786-O cells could be antagonized by miR-429 overexpression. Exogenous re-expression of CRKL abrogated miR-429 suppression on the migration and invasion of 786-O cells. Collectively, miR-429 deficiency negatively correlated with CRKL overexpression promoted the aggressiveness of cancer cells and advanced the clinical progression of ccRCC patients. miR-429-CRKL axial regulation provides new clues to the fundamental research, diagnosis and treatment of ccRCC.

MicroRNA-429 inhibits cancer cell proliferation and migration by targeting AKT1 in renal cell carcinoma

MicroRNAs (miRNAs or miR) serve as oncogenes and tumor suppressors. In a previous study, it was revealed that has-miRNA-429 (miR-429) is a tumor suppressor in 786-O renal cell carcinoma (RCC) cells. However, its mechanism in RCC remains to be determined. The present study aimed to explain the functional role and mechanism of miR-429 in RCC pathogenesis. Luciferase reporter assays demonstrated that miR-429 overexpression reduced the transcriptional activity of AKT serine/threonine kinase 1 (AKT1). Reverse transcripton-quantitative (RT-q) PCR and western blot analysis indicated that the mRNA and protein expression of AKT1 was downregulated in 786-O RCC cell lines when miR-429 was overexpressed, indicating that miR-429 may directly target AKT1 in RCC. Therefore, miR-429 overexpression enhanced the inhibition of tumor size and weight in nude mice in vivo. The current study indicated that the novel miR-429-regulated pathway may provide insights into RCC oncogenesis and metastasis.

miR-452 promotes cell metastasis and the epithelial to mesenchymal by targeting SOX7 in clear-cell renal-cell carcinoma

Clear-cell renal-cell carcinoma (ccRCC) is the most common renal cell carcinoma (RCC), representing 75%-80% of the cases of RCC, and characterized by a high recurrence rate and poor prognosis. miR-452 acts as a tumor promoter in several tumors, including ccRCC. The purpose of this study was to determine the role of miR-452 in ccRCC. miR-452 and SOX7 messenger RNA and protein levels were calculated by quantitative reverse transcription polymerase chain reaction and Western blot analysis. MTT and Transwell assays were utilized to measure proliferative and invasive abilities. The Kaplan-Meier method was used to evaluate the association between the expression of miR-452 or SOX7 and the overall survival of ccRCC patients. Our results showed that miR-452 was overexpressed in ccRCC tissues and cells, and upregulation of miR-452 predicted a poor 5-year survival in ccRCC patients. In contrast, expression of SOX7 was low and downregulation of SOX7 predicted poor prognosis in ccRCC. In addition, miR-452 promoted cell proliferation, invasion, and the EMT, while SOX7 reversed the function of miR-452 on cell proliferation and invasion in 786-O cells. In conclusion, miR-452 was shown to inhibit cell proliferation, invasion, and the EMT through SOX7 in ccRCC, and the newly identified miR-452/SOX7 axis provided novel insight into the pathogenesis of ccRCC.

LncRNA MIAT facilitated BM-MSCs differentiation into endothelial cells and restored erectile dysfunction via targeting miR-200a in a rat model of erectile dysfunction

BACKGROUND

Bone-marrow derived mesenchymal stem cells (BM-MSCs) implantation effectively restored rats' erectile dysfunction (ED). Long noncoding RNA (LncRNA)-myocardial infarction-associated transcript (MIAT) has been reported to play an important role in regulating endothelial cells (ECs) function via vascular endothelial growth factor (VEGF) that induced BM-MSCs differentiation into ECs. However, the molecular functions and biological roles of lncRNA MIAT in ED remained unclear.

METHODS

The rat model of ED was established. Quantitative real-time PCR (qRT-PCR) and western blotting were used to detect the expression of lncRNA MIAT, von Willebrand factor (vWF), vascular endothelial cadherin (VE-cadherin), endothelial NO synthase (eNOS) and VEGF following BM-MSCs transfection. Erectile function was evaluated by intra-cavernous pressure/mean artery pressure (ICP/MAP). Furthermore, RNA immunoprecipitation (RIP) assay and RNA pull down as well as luciferase reporter assay were carried out to examine the interaction among lncRNA MIAT, miR-200a and VEGF.

RESULTS

BM-MSCs restored ED by upregulating lncRNA MIAT. LncRNA MIAT was upregulated in a time-dependent manner during BM-MSCs differentiation into ECs. LncRNA MIAT regulated VEGF via targeting miR-200a, thereby promoting BM-MSCs differentiation into ECs. LncRNA MIAT knockdown in vivo abolished the effect of BM-MSCs on ED.

CONCLUSION

LncRNA MIAT promoted BM-MSCs differentiation into ECs and restored ED via miR-200a.

MiR-429 Regulated by Endothelial Monocyte Activating Polypeptide-II (EMAP-II) Influences Blood-Tumor Barrier Permeability by Inhibiting the Expressions of ZO-1, Occludin and Claudin-5

The blood-tumor barrier (BTB) hinders delivery of chemotherapeutic drugs to tumors in the brain; previous studies have shown that the BTB can be selectively opened by endothelial monocyte activating polypeptide-II (EMAP-II), but the specific mechanism involved remains elusive. In this study, we found that microRNA-429 (miR-429) expression in glioma vascular endothelial cells (GECs) was far lower than in human brain microvascular endothelial cells (ECs). miR-429 had lower expression in GECs and glioma tissues compared to ECs or normal tissues of the brain. Furthermore, miR-429 had lower expression in high grade glioma (HGG) than in low grade glioma (LGG). In in vitro BTB models, we also found that EMAP-II significantly increased BTB permeability, decreased expression of ZO-1, occludin and claudin-5 in GECs, in a time- and dose-dependent manner. EMAP-II greatly increased miR-429 expression in GECs of the BTB models in vitro. Overexpression of miR-429 in GECs significantly decreased the transepithelial electric resistance (TEER) values in BTB models, and led to enhanced horseradish peroxidase (HRP) flux. Overexpression of miR-429 in GECs significantly decreased the expression of tight junction (TJ)-associated proteins (ZO-1, occludin and claudin-5), and decreased the distribution continuity. Silencing of miR-429 in GECs increased the expression of TJ-associated proteins and the distribution continuity. The dual-luciferase reporter assay revealed that ZO-1 and occludin were target genes of miR-429, and we demonstrated that miR-429 overexpression markedly down-regulated protein expression of p70S6K, as well as its phosphorylation levels. The dual-luciferase reporter assay also showed that p70S6K was a target gene of miR-429; miR-429 overexpression down-regulated expression and phosphorylation levels of p70S6K, and also decreased phosphorylation levels of S6 and increased BTB permeability. Conversely, silencing of miR-429 increased the expression and phosphorylation levels of p70S6K, and increased phosphorylation levels of S6, while decreasing BTB permeability. In conclusion, the results indicated that EMAP-II caused an increase in miR-429 expression that directly targeted TJ-associated proteins, which were negatively regulated; on the other hand, miR-429 down-regulated the expression of TJ-associated proteins by targeting p70S6K, also negatively regulated. As a result, the BTB permeability increased.

Soft-shelled turtle peptide modulates microRNA profile in human gastric cancer AGS cells

Cancer prevention using natural micronutrition on epigenetic mechanisms primarily revolves around plant extracts. However, the role of macronutrition, including animal peptides, on epigenetic modification in cancer has been elusive. In traditional Chinese medicine, the soft-shelled turtle has a long-history of being a functional food that strengthens immunity through unknown mechanisms. The present study aimed to investigate the impact of soft-shelled turtle peptide on microRNA (miRNA) expression in gastric cancer (GC) cells and to analyze the potential anticancer mechanisms for GC. Affymetrix GeneChip miRNA 3.0 Array and quantitative polymerase chain reaction were used to detect the miRNA expression profile in human GC AGS cells treated with the soft-shelled turtle peptide. The results demonstrated that 101 miRNAs (49 upregulated miRNAs and 52 downregulated miRNAs) were significantly differentially expressed in the AGS cells following soft-shelled turtle peptide treatment. Several tumor suppressor miRNAs were upregulated markedly, including miRNA-375, let-7d, miRNA-429, miRNA-148a/148b and miRNA-34a. Pathway analysis indicated that soft-shelled turtle peptide may function with anticancer properties through the Hippo signaling pathway and the forkhead box O signaling pathway. Therefore, these results demonstrated that soft-shelled turtle peptide has the capacity to influence cancer-related pathways through the regulation of miRNA expression in GC cells.

MiR-367 regulates cell proliferation and metastasis by targeting metastasis-associated protein 3 (MTA3) in clear-cell renal cell carcinoma

Clear-cell renal cell carcinoma (ccRCC) is an aggressive and malignant kidney cancer which has the worst prognosis. Although microRNAs (miRNAs) have recently been identified as a novel class of regulators in oncogenesis and metastasis, there are few studies on their participation in ccRCC. In the present study, we observed that miR-367 expression was increased in both human ccRCC tissues and cell lines. Cell proliferation was evaluated by MTT assay and 5-Ethynyl-2′-deoxyuridine (EdU) assay kit, which indicated that inhibition of miR-367 could suppress the ccRCC proliferation. Forced expression of miR-367 substantially induced cell migration and invasion evidenced by wound-healing and transwell assays, and this carcinogenesis could be abolished by miR-367 inhibitor treatment. Further analysis identified Metastasis-Associated Protein 3 (MTA3) as a direct target of miR-367. QRT-PCR and western blot results indicated the correlative expression of miR-367 and MTA3 in ccRCC tissue samples. Overexpression of MTA3 reversed miR-367-induced cell proliferation, migration and invasion. Our data uncovered a novel molecular interaction between miR-367 and MTA3, indicating a therapeutic strategy of miR-367 for ccRCC.

VEGF-A/VEGFR2 signaling network in endothelial cells relevant to angiogenesis

Vascular endothelial growth factor-A (VEGF-A) is essential for endothelial cell functions associated with angiogenesis. Signal transduction networks initiated by VEGFA/VEGFR2, the most prominent ligand-receptor complex in the VEGF system, leads to endothelial cell proliferation, migration, survival and new vessel formation involved in angiogenesis. Considering its biomedical importance, we have developed the first comprehensive map of endothelial cell-specific signaling events of VEGFA/VEGFR2 system pertaining to angiogenesis. Screening over 20,000 published research articles and following the post-translational modification (PTM) and site specificity of VEGFR2, we have documented 240 proteins and their diverse PTM-dependent reactions involved in VEGFA/VEGFR2 signal transduction. From the ligand-receptor complex, this map has been extended to the level of major transcriptionally regulated genes for which the signaling cascades leading to their transcription factors are reported. We believe that this map would serve as a novel platform for reference, integration, and representation and more significantly, the progressive analysis of dynamic features of VEGF signaling in endothelial cells including their cross-talks with other ligand-receptor systems involved in angiogenesis.