MicroRNA-7 Exerts Antiangiogenic Effect on Colorectal Cancer via ERK Signaling

Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7

OBJECTIVE

To observe the angiogenesis effect of electroacupuncture (EA) at Shuigou acupoint (GV 26) in the treatment of cerebral ischemia, and explore the value of miRNA-7 (miR-7) in it.

METHODS

First, 48 mice were randomly divided into sham operation, middle cerebral artery occlusion (MCAO) model, and EA treatment groups. Then 9 mice were divided into carrier control group, miR-7 knockout group and miR-7 overexpression group (n=3 each group). Finally, 20 mice were divided into model and carrier control group, model and miR-7 knockout group, EA treatment and carrier control group and EA treatment and miR-7 overexpression group, with 3-6 mice in each group. The MCAO model was established in the MCAO and EA groups. Neurological deficit score and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to evaluate the severity of cerebral ischemia. Hematoxylin-eosin staining was used to describe basic pathological changes. Immunohistochemistry was used to quantify cerebral microvessel density. Real-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor (KLF4/VEGF) and angiopoietin-2 (ANG-2) in the ischemic cerebral cortex.

RESULTS

After EA, neurological deficit scores and infarction volumes decreased, and the density of cerebral microvessels increased. In the MCAO group, miR-7 expression was higher than that in the sham group (P<0.01). After EA at GV 26, miR-7 expression decreased (P<0.01) and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group (P<0.01). After EA combined with overexpression of miR-7, the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group (P<0.01). After miR-7 knockdown, the expression of KLF4/VEGF and ANG-2 increased (P<0.05 or P<0.01).

CONCLUSIONS

EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEGF and ANG-2.

Circular RNA, hsa_circRNA_102049, promotes colorectal cancer cell migration and invasion via binding and suppressing miRNA‑455‑3p

Colorectal cancer (CRC) is the second most prevalent malignant gastrointestinal tumor type worldwide, displaying poor prognosis. Accumulating studies have reported the significance of circular RNAs (circRNAs) and microRNAs (miRNAs) in CRC carcinogenesis and development. At present, the functions and mechanisms of action underlying the circular RNA, hsa_circRNA_102049, in CRC are not completely understood. The present study aimed to establish the involvement of hsa_circRNA_102049 in CRC, as well as the associated mechanisms. The expression levels of hsa_circRNA_102049 and miRNA-455-3p were measured in CRC cell lines and tissues via reverse transcription-quantitative PCR. CRC progression was evaluated by performing Cell Counting Kit-8, flow cytometry, wound healing and Transwell invasion assays. The results demonstrated that hsa_circRNA_102049 was highly expressed in both CRC tissues and cell lines, which was associated with enhanced CRC cell proliferation, migration and invasion. Furthermore, miR-455-3p expression was downregulated in CRC cells and served as a target of has_circRNA_102049, which was validated by performing the dual luciferase reporter assay. hsa_circRNA_102049 knockdown significantly increased miR-455-3p expression, which was significantly reversed by co-transfection with the miR-455-3p inhibitor. Notably, miRNA-455-3p overexpression alleviated hsa_circRNA_102049-mediated induction of CRC cell proliferation, migration and invasion. The present study clearly demonstrated that miRNA-455-3p was a target of hsa_circRNA_102049. Moreover, the results indicated that the circular RNA, hsa_circRNA_102049, may function as a tumor promoter in CRC via directly sponging miRNA-455-3p.

miR-7, miR-10a and miR-143 Expression May Predict Response to Bevacizumab Plus Chemotherapy in Patients with Metastatic Colorectal Cancer

Purpose

Bevacizumab is a monoclonal antibody that binds to vascular endothelial growth factor A. It is currently used in combination with chemotherapy to treat metastatic colorectal cancer. This therapy is not equally effective in every patient; in some, mechanisms of resistance arise that remain poorly understood. The aim of the present work was to determine whether the expression of 26 miRNAs could be associated with the effectiveness of bevacizumab plus chemotherapy, with progression-free survival (PFS), and with overall survival (OS) in metastatic colorectal cancer.

Patients and Methods

Paraffin-embedded biopsies from 76 patients with metastatic colorectal cancer were collected to isolate miRNAs. The expression of 26 miRNAs was analyzed by quantitative RT-PCR. For the purpose of analysis, patients were classified as either “responders” (PFS ≥6 months since beginning treatment) or “non-responders” (PFS <6 months). For the analysis of PFS and OS, patients were classified into two groups using the median gene expression value as the cut-off point (“high” [≥50% percentile] or “low” [<50% percentile]). Time-to-event data were analyzed using the Kaplan–Meier method and compared by the log rank test. Cox regression was used to estimate hazard ratios (HR) and their 95% confidence intervals.

Results

miR-7-5p and miR-10a-5p were more strongly expressed in non-responders than responders (p=0.049 and p=0.043, respectively), and OS was poorer in patients showing these higher expression levels (HR=2.54, 95% CI 1.42–4.55, p=0. 001, and HR=1.81, 95% CI 1.02–3.20, p=0.039, respectively). The overexpression of miR-143-3p, however, was associated with a better prognosis and significantly better PFS (HR=0.57; 95% CI: 0.33–0.96; p=0.033).

Conclusion

High expression values for miR-7-5p and miR-10a-5p might be considered markers of a poorer prognosis in patients with metastatic colorectal cancer treated with bevacizumab plus chemotherapy, while the same for miR-143-3p might be a marker of better outcomes.

miR‑125a‑5p and miR‑7 inhibits the proliferation, migration and invasion of vascular smooth muscle cell by targeting EGFR

The ectopic proliferation, migration and invasion of vascular smooth muscle cells (VSMCs) contributes to the progression of various human vascular diseases. Accumulating evidence has demonstrated that microRNAs (miRs) exert vital functions in the proliferation and invasion of VSMCs. The current study aimed to elucidate the functions of miR-125a-5p and miR-7 in VSMCs and investigate the associated molecular mechanisms. The results of EdU and reverse transcription-quantitative PCR assays revealed that platelet-derived growth factor (PDGF)-BB enhanced the proliferation of VSMCs and significantly reduced the expression of miR-125a-5p and miR-7. miR-125a-5p or miR-7 overexpression significantly ameliorated PDGF-BB-induced proliferation, migration and invasion of VSMCs. Furthermore, the results demonstrated that epidermal growth factor receptor (EGFR) may be a target mRNA of miR-125a-5p and miR-7 in VSMCs. The results of western blot analysis indicated that co-transfection of miR-125a-5p mimics or miR-7 mimics distinctly decreased the protein expression of EGFR in EGFR-overexpressed VSMCs. Moreover, rescue experiments indicated that EGFR overexpression alleviated the suppressive impact of the miR-125a-5p and miR-7 s on the growth, migration and invasion of VSMCs. In conclusion, the current study identified that miR-125a-5p and miR-7 repressed the growth, migration and invasion of PDGF-BB-stimulated VSMCs by, at least partially, targeting EGFR. The current study verified that miR-125a-5p and miR-7 may be used as feasible therapeutic targets for cardiovascular diseases.

Regulation of angiogenesis by microRNAs in cancer

MicroRNAs (miRs) are endogenous, small, non‑coding RNA molecules with ~22 nucleotides, and are involved in regulating the expression of multiple genes and controlling cellular functions. miRs serve key roles in angiogenesis by regulating the proliferation, differentiation, apoptosis and migration of endothelial cells. Regulation of angiogenesis is essential for several physiological and pathological processes, particularly for tumor development and progression. Therefore, it is important to investigate the roles served by miRs in angiogenesis as this may aid in discovering novel strategies for treating tumors via modulating angiogenesis. In this review, miRNA biogenesis, regulation and functions are described with new information and corresponding references. In particular, the latest advances in the role of various miRs and their target genes involved in tumor angiogenesis were updated. Next, different signaling pathways by which miRNAs could be regulated in different types of tumor progression were addressed. Furthermore, the potential clinical value of miRs as biomarkers for diagnosing and monitoring the response to therapy, as well as their ability to regulate tumor angiogenesis and the mechanism underlying this regulation, were investigated.

MicroRNAs and angiogenesis: a new era for the management of colorectal cancer

MicroRNAs (miRNAs) are a class of small noncoding RNA molecules containing only 20–22 nucleotides. MiRNAs play a role in gene silencing and translation suppression by targeting and binding to mRNA. Proper control of miRNA expression is very important for maintaining a normal physiological environment because miRNAs can affect most cellular pathways, including cell cycle checkpoint, cell proliferation, and apoptosis pathways, and have a wide range of target genes. With these properties, miRNAs can modulate multiple signalling pathways involved in cancer development, such as cell proliferation, apoptosis, and migration pathways. MiRNAs that activate or inhibit the molecular pathway related to tumour angiogenesis are common topics of research. Angiogenesis promotes tumorigenesis and metastasis by providing oxygen and diffusible nutrients and releasing proangiogenic factors and is one of the hallmarks of tumour progression. CRC is one of the most common tumours, and metastasis has always been a difficult issue in its treatment. Although comprehensive treatments, such as surgery, radiotherapy, chemotherapy, and targeted therapy, have prolonged the survival of CRC patients, the overall response is not optimistic. Therefore, there is an urgent need to find new therapeutic targets to improve CRC treatment. In a series of recent reports, miRNAs have been shown to bidirectionally regulate angiogenesis in colorectal cancer. Many miRNAs can directly act on VEGF or inhibit angiogenesis through other pathways (HIF-1a, PI3K/AKT, etc.), while some miRNAs, specifically many exosomal miRNAs, are capable of promoting CRC angiogenesis. Understanding the mechanism of action of miRNAs in angiogenesis is of great significance for finding new targets for the treatment of tumour angiogenesis. Deciphering the exact role of specific miRNAs in angiogenesis is a challenge due to the high complexity of their actions. Here, we describe the latest advances in the understanding of miRNAs and their corresponding targets that play a role in CRC angiogenesis and discuss possible miRNA-based therapeutic strategies.

Angiogenic Actions of Paeoniflorin on Endothelial Progenitor Cells and in Ischemic Stroke Rat Model

Ischemic stroke is one of the major diseases with high morbidity, mortality, and disability rate all over the world. Chinese herb-derived active components would provide valuable candidate compounds for ischemic stroke therapy. Paeoniflorin (PF) is an active ingredient from Paeoniae Radix which possesses neurovascular effect after ischemia. However, so far, few studies are reported on the efficacy and mechanism of PF from angiogenesis aspects. Results from our in vitro studies showed that the ability for proliferation, migration, and tube formation in bone marrow-derived endothelial progenitor cells (BM-EPCs) was promoted by coculturing with PF (100 [Formula: see text]M). Furthermore, to investigate the angiogenic effects of PF in vivo, we constructed an ischemic stroke model in rats and found that PF could reduce cerebral infarction, alleviate pathological injury, and increase the secretion of pro-angiogenic factors and cerebral vascular density after intraperitonially administration of 40 mg ⋅ kg[Formula: see text] ⋅ day[Formula: see text] for 14 days. Up-regulating the expression of VEGF/VEGF-R₂ might be the mechanism of PF's angiogenic action. In conclusion, the present study provides evidence that PF is an active monomer of Traditional Chinese Medicine which shows angiogenic actions on endothelial progenitor cells and in ischemic stroke rat model.

The Role of miRNA-7 in the Biology of Cancer and Modulation of Drug Resistance

MicroRNAs (miRNAs, miRs) are small non-coding RNA (ncRNA) molecules capable of regulating post-transcriptional gene expression. Imbalances in the miRNA network have been associated with the development of many pathological conditions and diseases, including cancer. Recently, miRNAs have also been linked to the phenomenon of multidrug resistance (MDR). MiR-7 is one of the extensively studied miRNAs and its role in cancer progression and MDR modulation has been highlighted. MiR-7 is engaged in multiple cellular pathways and acts as a tumor suppressor in the majority of human neoplasia. Its depletion limits the effectiveness of anti-cancer therapies, while its restoration sensitizes cells to the administered drugs. Therefore, miR-7 might be considered as a potential adjuvant agent, which can increase the efficiency of standard chemotherapeutics.

MicroRNA‑195 suppresses cell proliferation, migration and invasion in epithelial ovarian carcinoma via inhibition of the CDC42/CCND1 pathway

Epithelial ovarian carcinoma (EOC) is the most common cause of gynecological cancer mortality, and poses a threat to women. MicroRNA-195 (miR-195) has been reported to induce apoptosis of human OVCAR-3 cells by inhibiting the VEGFR2/AKT pathway. However, the role of miR-195 in EOC remains unknown. A previous study reported that cell division cycle 42 (CDC42) can serve as a target gene of miR-195 and mediate malignant progression of esophageal squamous cell carcinoma (ESCC). The aim of the present study was to investigate the role of miR-195 in EOC and the regulation in CDC42/CCND1 pathway. Tissues samples and clinical materials were collected from 78 enrolled patients with EOC to analyze the expression and clinical significance of miR-195, CDC42 and cyclin D1 (CCND1). Human EOC cell lines OVCA420, OVCAR-3, A2780 and SKOV3 cell lines were used to assess the expression and function of miR-195, CDC42 and CCND1 in vitro. Cell proliferation, the cell cycle and apoptosis, as well as the cell migratory and invasive abilities were detected in vitro using BrdU incorporation, colony formation, wound healing and Transwell invasion assays, along with flow cytometry. miR-195 was downregulated, while CDC42 and CCND1 were upregulated in human EOC tissues and cells, and the aberrant expression of both was associated with increased EOC malignancy. Moreover, miR-195 expression was negatively correlated with CDC42 and CCND1 expression levels, and negatively regulated these expression levels. Thus, it was suggested that miR-195 functions as a tumor suppressor, but CDC42 and CCND1 act as tumor promoters based their abilities to enhance cell proliferation, cell cycle entry, migration and invasion, as well as decrease apoptosis in OVCAR-3 cells. the present results demonstrated that miR-195 inhibited human EOC progression by downregulating CDC42 and CCND1 expression. Furthermore, it was identified that miR-195, CDC42 and CCND1 may be effective biomarkers for EOC diagnosis and treatment.

MicroRNA-7, synergizes with RORα, negatively controls the pathology of brain tissue inflammation

BACKGROUND

Accumulating evidence has documented that microRNA-7 (miR-7) plays an important role in the pathology of various diseases. However, the potential role of miR-7 in brain tissue inflammation (BTI) remains unclear.

METHODS

We detected the expression of miR-7 in LPS-induced murine BTI model and observed the possible effects of miR-7 deficiency on the pathology of BTI. To elucidate the mechanism, the target gene of miR-7 was screened out by Gene chip assay and its potential roles in BTI were evaluated by Western blot, immunofluorescence, and RNAi assay, respectively.

RESULTS

MiR-7 was upregulated in brain tissue in BTI mice and its deficiency could significantly aggravate the pathology of brain tissue. Moreover, RORα, a new target molecule of miR-7, was upregulated in brain tissue from miR-7 deficiency BTI mice. Of note, downregulation of RORα could remarkably exacerbate the pathology of brain tissue and elevate the transduction of NF-κB and ERK1/2 signaling pathways in brain tissue from miR-7 deficiency BTI mice. Furthermore, RORα and miR-7 were dominantly co-expressed in neurons of BTI mice. Finally, RORα synergized with miR-7 to control the inflammatory reaction of neuronal cells in response to LPS stimulation.

CONCLUSIONS

MiR-7 expression is upregulated in BTI model. Moreover, miR-7 synergizes with its target gene RORα to control the inflammation reaction of neurons, thereby orchestrating the pathology of BTI.

TNIP1 Inhibits Proliferation And Promotes Apoptosis In Clear Cell Renal Carcinoma Through Targeting C/Ebpβ

Background/Purpose

TNF-α-induced protein 3-interacting protein 1 (TNIP1) is active in various cancers, but its expression and function in renal cell carcinoma (RCC) have not been described. This study investigated the role of TNIP1 in clear cell renal cell carcinomas (ccRCC), which accounts for 75–80% of RCC and has a poor prognosis.

Methods

The expression of TNIP1 in human ccRCC tissues and cells was detected by real-time quantitative reverse transcription–polymerase chain reaction (qRT-PCR), Western blot (WB), and immunohistochemical (IHC) staining. Cell proliferation was assayed by a cell counting kit (CCK)-8 assay; cell cycle analysis and apoptosis assay were done by flow cytometry.

Results

TNIP1 is downregulated in both ccRCC human tissues and cells. Besides, TNIP1 downregulation promoted cell proliferation with more cell cycle entry, and inhibited apoptosis. TNIP1 downregulation was associated with increased of expression of the Bcl-2 anti-apoptosis gene and decreased expression of the Bax apoptosis-promoting gene and cleaved-caspase-3 by negatively regulating C/EBPβ expression.

Conclusion

TNIP1 acted as a tumor-inhibitor in ccRCC by targeting C/EBPβ. The results warrant study of TNIP1 as a potential diagnostic marker and therapeutic target of ccRCC.

The Importance of microRNAs in RAS Oncogenic Activation in Human Cancer

microRNAs (miRNAs) regulate gene expression by modulating the translation of protein-coding RNAs. Their aberrant expression is involved in various human diseases, including cancer. Here, we summarize the experimental pieces of evidence that proved how dysregulated miRNA expression can lead to RAS (HRAS, KRAS, or NRAS) activation irrespective of their oncogenic mutations. These findings revealed relevant pathogenic mechanisms as well as mechanisms of resistance to target therapies. Based on this knowledge, potential approaches for the control of RAS oncogenic activation can be envisioned.