miR-149 Inhibits Non-Small-Cell Lung Cancer Cells EMT by Targeting FOXM1

Comprehensive analysis of microRNA-regulated protein interaction network reveals the tumor suppressive role of microRNA-149 in human hepatocellular carcinoma via targeting AKT-mTOR pathway

BACKGROUND

Our previous study identified AKT1, AKT2 and AKT3 as unfavorable prognostic factors for patients with hepatocellular carcinoma (HCC). However, limited data are available on their exact mechanisms in HCC. Since microRNAs (miRNAs) are implicated in various human cancers including HCC, we aimed to screen miRNAs targeting AKTs and investigate their underlying mechanisms in HCC by integrating bioinformatics prediction, network analysis, functional assay and clinical validation.

METHODS

Five online programs of miRNA target prediction and RNAhybrid which calculate the minimum free energy (MFE) of the duplex miRNA:mRNA were used to screen optimized miRNA-AKT interactions. Then, miRNA-regulated protein interaction network was constructed and 5 topological features ('Degree', 'Node-betweenness', 'Edge-betweenness', 'Closeness' and 'Modularity') were analyzed to link candidate miRNA-AKT interactions to oncogenesis and cancer hallmarks. Further systematic experiments were performed to validate the prediction results.

RESULTS

Six optimized miRNA-AKT interactions (miR-149-AKT1, miR-302d-AKT1, miR-184-AKT2, miR-708-AKT2, miR-122-AKT3 and miR-124-AKT3) were obtained by combining the miRNA target prediction and MFE calculation. Then, 103 validated targets for the 6 candidate miRNAs were collected from miRTarBase. According to the enrichment analysis on GO items and KEGG pathways, these validated targets were significantly enriched in many known oncogenic pathways for HCC. In addition, miRNA-regulated protein interaction network were divided into 5 functional modules. Importantly, AKT1 and its interaction with mTOR respectively had the highest node-betweenness and edge-betweenness, implying their bottleneck roles in the network. Further experiments confirmed that miRNA-149 directly targeted AKT1 in HCC by a miRNA luciferase reporter approach. Then, re-expression of miR-149 significantly inhibited HCC cell proliferation and tumorigenicity by regulating AKT1/mTOR pathway. Notably, miR-149 down-regulation in clinical HCC tissues was correlated with tumor aggressiveness and poor prognosis of patients.

CONCLUSION

This comprehensive analysis identified a list of miRNAs targeting AKTs and revealed their critical roles in HCC malignant progression. Especially, miR-149 may function as a tumor suppressive miRNA and play an important role in inhibiting the HCC tumorigenesis by modulating the AKT/mTOR pathway. Our clinical evidence also highlight the prognostic potential of miR-149 in HCC. The newly identified miR-149/AKT/mTOR axis might be a promising therapeutic target in the prevention and treatment of HCC.

miR-320 enhances the sensitivity of human colon cancer cells to chemoradiotherapy in vitro by targeting FOXM1

miR-320 expression level is found to be down-regulated in human colon cancer. To date, however, its underlying mechanisms in the chemo-resistance remain largely unknown. In this study, we demonstrated that ectopic expression of miR-320 led to inhibit HCT-116 cell proliferation, invasion and hypersensitivity to 5-Fu and Oxaliplatin. Also, knockdown of miR-320 reversed these effects in HT-29 cells. Furthermore, we identified an oncogene, FOXM1, as a direct target of miR-320. In addition, miR-320 could inactive the activity of Wnt/β-catenin pathway. Finally, we found that miR-320 and FOXM1 protein had a negative correlation in colon cancer tissues and adjacent normal tissues. These findings implied that miR-320-FOXM1 axis may overcome chemo-resistance of colon cancer cells and provide a new therapeutic target for the treatment of colon cancer.

Association of the miR-149 Rs2292832 polymorphism with papillary thyroid cancer risk and clinicopathologic characteristics in a Chinese population

(1) Background: The genetic predisposition to papillary thyroid cancer (PTC) is far from clearly elucidated. Rs2292832 is a genetic polymorphism that located in the precursor of mir-149 and has been studied in diverse cancers. Thus far, the role of rs2292832 in PTC tumorigenesis and progression was unclear; (2) Method: Rs2292832 was genotyped in 838 PTCs, 495 patients with thyroid benign tumors (BNs) and 1006 controls in a Chinese Han population. Clinicopathological data was collected and compared. The expression level of mature mir-149 was examined in 55 normal thyroid tissue samples; (3) Results: The CC genotype of rs2292832 was significantly associated with an increased risk of PTC compared with TT homozygote (OR = 1.60, 95% CI: 1.72–2.20, p = 0.003) and TT/TC combined genotype (OR = 1.54, 95% CI: 1.14–2.09, p = 0.005). Rs2292832 is an independent risk factor correlated with tumor invasion (p = 0.006) and higher T stage in PTC patients (p = 0.007), but uncorrelated with short-term disease persistence of PTC. PTC subjects carrying CC genotype have lower mir-149-5p expression than those with TC genotype (p = 0.002). Twelve predicted target genes have been identified by collaboratively using computational tools; (4) Conclusion: Rs2292832 was possibly involved in the susceptibility and local progression of PTC in Chinese patients, by altering the expression level of mir-149-5p and its target genes.

Epigenetics in the Pathogenesis of Esophageal Adenocarcinoma

Epigenetic influences, such as DNA methylation, histone acetylation, and up-regulation/down-regulation of genes by microRNAs, change the genetic makeup of an individual without affecting DNA base-pair sequences. Indeed, epigenetic changes play an integral role in the progression from normal esophageal mucosa to Barrett's esophagus to esophageal adenocarcinoma via dysplasia-metaplasia-neoplasia sequence. Many genes involved in esophageal adenocarcinoma display hypermethylation, leading to their down-regulation. The classes of these genes include cell cycle control, DNA and growth factor repair, tumor suppressors, antimetastasis, Wnt-related genes, and proapoptotic genes. Histone acetylation in the pathophysiology of esophageal diseases has not been thoroughly investigated, and its critical role in the development of esophageal adenocarcinoma is less defined. Many microRNAs have been associated with the development of Barrett's esophagus and esophageal adenocarcinoma. Here, we critically addressed the specific steps most closely influenced by microRNAs in the progression from Barrett's esophagus to esophageal adenocarcinoma. However, microRNAs can target up to hundreds of genes, making it difficult to correlate directly with a given phenotype of the disease. Esophageal adenocarcinoma progressing from premalignant condition of Barrett's esophagus carries an extremely poor prognosis. Risk stratification for patients based on their epigenetic profiles may be useful in providing more targeted and directed treatment to patients.

Prognostic role of common microRNA polymorphisms in cancers: evidence from a meta-analysis

BACKGROUND

The morbidity and mortality of cancer increase remarkably every year. It's a heavy burden for family and society. The detection of prognostic biomarkers can help to improve the theraputic effect and prolong the lifetime of patients. microRNAs have an influential role in cancer prognosis. The results of articles discussing the relationship between microRNA polymorphisms and cancer prognosis are inconsistent.

METHODS

We conduct a meta-analysis of 19 publications concerning the association of four common polymorphisms, mir-146a rs2910164, mir-149 rs2292832, mir-196a2 rs11614913 and mir-499 rs3746444, with cancer prognosis. Pooled Hazard Ratios with 95% Confidence Intervals for the relationship between four genetic polymorphisms and Overall Survival, Recurrence-free Survival, Disease-free survival, recurrence are calculated. Subgroup analysis by population and type of tumor are conducted.

RESULTS

GG genotype of mir-146a may be the protective factor for overall survival, especially in Caucasian population. C-containing genotypes of mir-196a2 act as a risk role for overall survival. The same result exists in Asian population, in Non-Small Cell Lung Cancer and digestive cancer. The patients with C allele of mir-149 have a better overall survival, especially in Non-Small Cell Lung Cancer. No significant results are obtained for mir-499 polymorphisms.

CONCLUSIONS

Genetic polymorphisms in mir-146a, mir-196a2 and mir-149 may be associated with overall survival. This effect varies with different types of cancer. Genetic polymorphism in mir-499 may have nothing to do with cancer prognosis.

Methylation-regulated miR-149 modulates chemoresistance by targeting GlcNAc N-deacetylase/N-sulfotransferase-1 in human breast cancer

Dysregulation of microRNA is strongly implicated in the chemoresistance of cancer. In this study, we found that miR-149 was downregulated and involved in chemoresistance in adriamycin (ADM)-resistant human breast cancer cells (MCF-7/ADM). Downregulation of miR-149 was related to hypermethylation of its 5'-UTR; this methylation also affected the expression of the glypican 1 gene, which is both the host and the target gene of miR-149. Furthermore, we found that miR-149 modulated chemoresistance through targeting the expression of GlcNAc N-deacetylase/N-sulfotransferase-1 (NDST1). With downregulated miR-149, NDST1 expression was increased in chemoresistant MCF-7/ADM cells versus control MCF-7 wild-type cells. The increased NDST1 then activated a heparan sulfate-related pathway involving activation of heparanase. Finally, expression of miR-149 and NDST1 was confirmed in clinical chemoresistant samples of breast cancers receiving anthracycline/taxane-based chemotherapies. The high expression of NDST1 was also an unfavorable predictor for distant relapse-free survival in Her2 and basal breast cancers. Taken together, our findings demonstrate that miR-149 is regulated by methylation, and is a modulator of cancer chemoresistance by targeting NDST1.

microRNA-548l is involved in the migration and invasion of non-small cell lung cancer by targeting the AKT1 signaling pathway

PURPOSE

microRNAs (miRNAs) have been documented playing a critical role in cancer development and progression. In this study, we investigated the role of miR-548l in non-small cell lung cancer (NSCLC) migration and invasion.

METHODS

microRNAs microarray analysis was used to detect the differentially expressed miRNAs between various metastatic levels of NSCLC cells and further confirmed by real-time PCR analysis. To facilitate the delineation of the role of selected miR-548l in NSCLC pathology, we detected its expression in 22 NSCLC tissues. Proliferation, apoptosis, invasion and metastasis effects of the miRNA were evaluated using MTT, flow cytometry, wound healing and invasion assay following transfection with mimics and inhibitors. Luciferase assay and Western blot analysis were performed to assess miR-548l binding to AKT1 gene. AKT1 expression in the clinical tissues was evaluated using immunohistochemical staining.

RESULTS

The results showed a negative relationship between miR-548l expression and lymph node metastasis of NSCLC. Functional assays showed that over-expression of miR-548l suppressed NSCLC cell migration and invasion. Luciferase assays confirmed that miR-548l could directly bind to the 3' untranslated region of AKT1. Further data showed that the over-expression of AKT1 could rescue the effects of miR-548l in NSCLC cells, and the miR-548l expression was inversely correlated with AKT1 expression in NSCLC tissues. These results indicated that AKT1 was involved in miR-548l-induced suppression of NSCLC cell migration and invasion.

CONCLUSION

These results suggested that miR-548l may play a causal role through AKT1 in NSCLC invasion and metastasis.

miR149 rs71428439 polymorphism and risk of clear cell renal cell carcinoma: a case-control study

Clear cell renal cell carcinoma (CCRCC) is the most common subtype of renal cell cancer and accounts for 70 % of renal cell cancer. CCRCC remains an enigmatic tumor type, as the molecular genetic mechanisms are still unclear. MicroRNA (miR) 149 functions as a tumor suppressor and plays an important role in the carcinogenesis of renal cells. In this study, we enrolled 1,000 CCRCC patients and 1,000 cancer-free controls to evaluate the association of miR149 rs71428439 with the risk of CCRCC by a case-control study to determine the effects on CCRCC risk. miR149 rs71428439 was significantly associated with increased CCRCC risk (odds ratio (OR) for trend = 1.53, P for trend = 4.04 × 10(-11)), with ORs (95 % confidence intervals (CIs)) of 1.42 (1.17-1.72) associated with AG genotype and 2.27 (1.76-2.94) associated with GG genotype, compared with subjects with AA genotype. The expression levels of miR149 in cancer tissues were significantly lower than those in adjacent normal tissues (P = 0.005), and per G allele has significantly lower miR149 levels in both tumor tissues and adjacent normal tissues. Our data suggest that the GG genotypes of miR149 rs71428439 predispose their carriers to CCRCC, and miR149 rs71428439 may be a new biomarker for predicting the risk of CCRCC.

Association study of miR‑149 rs2292832 and miR‑608 rs4919510 and the risk of hepatocellular carcinoma in a large‑scale population

Polymorphisms in pre‑microRNAs (miRNAs) or mature miRNAs may influence miRNA processing or target binding, thus contributing to tumorigenesis and cancer development. The present study aimed to evaluate whether miR‑149 rs2292832 (C>T) and miR‑608 rs4919510 (G>C) are associated with the risk and clinical characteristics of hepatocellular carcinoma (HCC) in a large‑scale population. miR‑149 rs2292832 and miR‑608 rs4919510 were genotyped in a total of 993 patients with HCC and 992 unrelated healthy subjects by Sequenom MassARRAY. The results showed that, compared with the reference CC genotype, the TC+TT genotype of miR‑149 was more highly associated with HCC [CC vs. TC+TT: Odds ratio (OR)=1.384, 95% confidence interval (CI)=1.013‑1.892, P=0.041], and was also associated with an increased risk of hepatitis B virus (HBV)‑associated HCC (CC vs. TC+TT: OR=1.453, 95% CI=1.034‑2.042, P=0.031). However, no significant association between miRNA‑608 rs4919510 and the risk of HCC/HBV‑associated HCC was found. In addition, these two SNPs were shown not to be correlated with a range of clinical characteristics. The present study may provide an indicator for identification of the high risk of HCC in patients.

FOXM1: A key oncofoetal transcription factor in health and disease

Forkhead Box M1 (FOXM1) is a bona fide oncofoetal transcription factor, which orchestrates complex temporal and spatial gene expression throughout embryonic and foetal development as well as during adult tissue homeostasis and repair. Controlled FOXM1 expression and activity provides a balanced transcriptional programme to ensure proper growth and maturation during embryogenesis and foetal development as well as to manage appropriate homeostasis and repair of adult tissues. Conversely, deregulated FOXM1 upregulation likely affects cell migration, invasion, angiogenesis, stem cell renewal, DNA damage repair and cellular senescence, which impact tumour initiation, progression, metastasis, angiogenesis and drug resistance. A thorough understanding of the regulation and role of FOXM1 in health and in cancer should contribute to the development of better diagnostics and treatments for cancer as well as congenital disorders and other developmental diseases.

Targeting forkhead box transcription factors FOXM1 and FOXO in leukemia (Review)

Deregulation of forkhead box (FOX) proteins has been found in many genetic diseases and malignancies including leukemia. Leukemia is a common neoplastic disease of the blood or bone marrow characterized by the presence of immature leukocytes and is one of the leading causes of death due to cancer. Forkhead transcription factors, FOXM1 and FOXO family members (FOXOs), are important mediators in leukemia development. Aberrant expression of FOXM1 and FOXOs results in leukemogenesis. Usually the expression of FOXM1 is upregulated, whereas the expression of FOXOs is downregulated due to phosphorylation, nuclear exclusion and degradation in leukemia. On the one hand, FOXOs are bona fide tumor suppressors, on the other hand, active FOXOs maintain leukemia stem cells and stimulate drug resistance genes, contributing to leukemogenesis. FOXM1 and FOXOs have been proven to be potential targets for the development of leukemia therapeutics. They are also valuable diagnostic and prognostic markers in leukemia for clinical applications. This review summarizes the present knowledge concerning the molecular mechanisms by which FOXM1 and FOXOs modulate leukemogenesis and leukemia development, the clinical relevance of these FOX proteins in leukemia and related areas that warrant further investigation.

miR149 functions as a tumor suppressor by controlling breast epithelial cell migration and invasion

Deregulated molecular signaling pathways are responsible for the altered adhesive, migratory, and invasive properties of cancer cells. The different breast cancer subtypes are characterized by the expression of distinct miRNAs, short non-coding RNAs that posttranscriptionally modulate the expression of entire gene networks. Profiling studies have revealed downregulation of miR149 in basal breast cancer. Here, we show that miR149 expression severely impairs cell spreading, migration, and invasion of basal-like breast cancer cells. We identify signaling molecules, including the small GTPases Rap1a and Rap1b, downstream of integrin receptors as miR149 targets, providing an explanation for the defective Src and Rac activation during cell adhesion and spreading upon miR149 expression. Suppression of cell spreading by miR149 could be rescued, at least in part, by expression of constitutively active Rac. Finally, we demonstrate that increased miR149 levels block lung colonization in vivo. On the basis of our findings, we propose that miR149 downregulation in basal breast cancer facilitates the metastatic dissemination of tumor cells by supporting aberrant Rac activation. Cancer Res; 74(18); 5256-65. ©2014 AACR.

MiR-506 suppresses proliferation and induces senescence by directly targeting the CDK4/6-FOXM1 axis in ovarian cancer

Ovarian carcinoma is the most lethal gynaecological malignancy. Better understanding of the molecular pathogenesis of this disease and effective targeted therapies are needed to improve patient outcomes. MicroRNAs play important roles in cancer progression and have the potential for use as either therapeutic agents or targets. Studies in other cancers have suggested that miR-506 has anti-tumour activity, but its function has yet to be elucidated. We found that deregulation of miR-506 in ovarian carcinoma promotes an aggressive phenotype. Ectopic over-expression of miR-506 in ovarian cancer cells was sufficient to inhibit proliferation and to promote senescence. We also demonstrated that CDK4 and CDK6 are direct targets of miR-506, and that miR-506 can inhibit CDK4/6-FOXM1 signalling, which is activated in the majority of serous ovarian carcinomas. This newly recognized miR-506-CDK4/6-FOXM1 axis provides further insight into the pathogenesis of ovarian carcinoma and identifies a potential novel therapeutic agent.

MiR-101 suppresses the epithelial-to-mesenchymal transition by targeting ZEB1 and ZEB2 in ovarian carcinoma

Ovarian carcinoma is the most lethal gynecologic malignancy; the majority of patients succumb to the disease within 5 years of diagnosis. The poor survival rate is attributed to diagnosis at advanced stage, when the tumor has metastasized. The epithelial-to-mesenchymal transition (EMT) is a necessary step toward metastatic tumor progression. Through integrated computational analysis, we recently identified a master microRNA (miRNA) network that includes miR-101 and regulates EMT in ovarian carcinoma. In the present study, we characterized the functions of miR-101. Using reporter gene assays, we demonstrated that miR-101 suppressed the expression of the E-cadherin repressors ZEB1 and ZEB2 by directly targeting the 3'-untranslated region (3'UTR) of both ZEB1 and ZEB2. Introduction of miR-101 significantly inhibited EMT and cell migration and invasion. Introducing cDNAs of ZEB1 and ZEB2 without 3'UTR abrogated miR-101-induced EMT alteration, respectively. Our findings showed that miR-101 represents a redundant mechanism for the miR-200 family that regulates EMT through two major E-cadherin transcriptional repressors.

Post-transcriptional regulatory network of epithelial-to-mesenchymal and mesenchymal-to-epithelial transitions

Epithelial-to-mesenchymal transition (EMT) and its reverse process, mesenchymal-to-epithelial transition (MET), play important roles in embryogenesis, stem cell biology, and cancer progression. EMT can be regulated by many signaling pathways and regulatory transcriptional networks. Furthermore, post-transcriptional regulatory networks regulate EMT; these networks include the long non-coding RNA (lncRNA) and microRNA (miRNA) families. Specifically, the miR-200 family, miR-101, miR-506, and several lncRNAs have been found to regulate EMT. Recent studies have illustrated that several lncRNAs are overexpressed in various cancers and that they can promote tumor metastasis by inducing EMT. MiRNA controls EMT by regulating EMT transcription factors or other EMT regulators, suggesting that lncRNAs and miRNA are novel therapeutic targets for the treatment of cancer. Further efforts have shown that non-coding-mediated EMT regulation is closely associated with epigenetic regulation through promoter methylation (e.g., miR-200 or miR-506) and protein regulation (e.g., SET8 via miR-502). The formation of gene fusions has also been found to promote EMT in prostate cancer. In this review, we discuss the post-transcriptional regulatory network that is involved in EMT and MET and how targeting EMT and MET may provide effective therapeutics for human disease.

miR-141 suppresses proliferation and motility of gastric cancer cells by targeting HDGF

miR-141 belongs to the miR-200 family, and has been found to be associated with numerous human malignancies; however, its role in gastric cancer (GC) has not been examined in detail. Here, we validated that miR-141 was decreased in GC tissues and cell lines. Forced expression of miR-141 significantly repressed GC cell proliferation and colony formation. Furthermore, miR-141 suppressed in vitro migration and invasion of GC cells. Hepatoma-derived growth factor (HDGF) was confirmed to be a direct target of miR-141 in GC cells. The suppressive effects of miR-141 on GC cell proliferation, colony formation, in vitro migration, and invasion were partially mediated by suppressing HDGF expression. Moreover, the expression of HDGF was negatively correlated with miR-141 in GC tissues. Our data suggest that miR-141 might be associated and plays essential role in GC progression.

miR-145 suppresses osteogenic differentiation by targeting Sp7

Osteogenesis depends on a coordinated network of transcription factors including Sp7. Emerging evidence indicates that microRNAs (miRNAs) act as pivotal regulators in various biological processes including osteoblast proliferation and differentiation. Here, we investigated the effect of miR-145 on osteogenic differentiation. miR-145 was decreased during osteogenic differentiation, which could suppress the osteogenic differentiation of C2C12 and MC3T3-E1 cells confirmed by gain- and loss-of-function experiments. Moreover, bioinformatic analysis combined with luciferase reporter assay, and Western blot validated that miR-145 negatively regulated Sp7 expression. Inhibition of Sp7 showed similar effect with miR-145 on osteogenic differentiation, whereas overexpression of Sp7 attenuated this effect. Collectively, these data indicate that miR-145 is a novel regulator of Sp7, and it suppresses the osteogenic differentiation of C2C12 and MC3T3-E1 cells.

Downregulation of miR-16 promotes growth and motility by targeting HDGF in non-small cell lung cancer cells

MicroRNAs play important roles in the development and progression of non-small cell lung cancer (NSCLC). miR-16 functions as a tumor-suppressor and is inhibited in several malignancies. Herein, we validated that miR-16 is downregulated in NSCLC tissue samples and cell lines. Ectopic expression of miR-16 significantly inhibited cell proliferation and colony formation. Moreover, miR-16 suppressed cell migration and invasion in NSCLC cells. Hepatoma-derived growth factor (HDGF) was found to be a direct target of miR-16 in NSCLC cell lines. Rescue experiments showed that the suppressive effect of miR-16 on cell proliferation, colony formation, migration, and invasion is partially mediated by inhibiting HDGF expression. This study indicates that miR-16 might be associated with NSCLC progression, and suggests an essential role for miR-16 in NSCLC.

IL-16 variability and modulation by antiallergic drugs in a murine experimental allergic rhinitis model

BACKGROUND

Interleukin-16 (IL-16) is a cytokine that induces selective migration of CD4+ cells and participates in inflammatory diseases including allergic rhinitis. Histamine and prostaglandin D(2) are important chemical mediators of allergic inflammation, and antiallergic drugs are commonly used for the treatment of allergic rhinitis. It remains unknown whether treatment with the drugs affects IL-16.

OBJECTIVE

We evaluated the variability of IL-16 and the effects of the antiallergic drugs fexofenadine (40 mg/kg/day) and ramatroban (30 mg/kg/day) on IL-16 in an OVA-sensitized BALB/c murine experimental allergic rhinitis model.

METHODS

We measured the expression level of IL-16 protein in the mouse nasal septal mucosa by immunohistochemistry, and the serum level of IL-16 by ELISA. Several other parameters associated with allergic rhinitis (nasal symptoms, OVA-specific IgE, eosinophil and T cell infiltration) were also measured.

RESULTS

Local and systemic expressions of IL-16 were significantly increased in OVA-sensitized mice when compared to the nonsensitized group. Fexofenadine and ramatroban significantly inhibited the following OVA-induced allergic features when compared to the nontreated sensitized group: sneezing, nasal rubbing, eosinophil infiltration, IL-16 expressions in nasal tissue, and serum IL-16 level. Serum OVA-specific IgE and local T cell infiltration were reduced, but they did not reach significant values.

CONCLUSIONS

These results suggest that IL-16 was both systemically and locally upregulated in the murine allergic rhinitis model and that IL-16 changed in parallel to allergic state by treatment with the drugs.