Apigenin intervenes in liver fibrosis by regulating PKM2-HIF-1α mediated oxidative stress.

Apigenin (API) is a natural flavonoid compound with antioxidant, anti fibrotic, anti-inflammatory and other effects, but there is limited research on the effect of API on liver fibrosis. This study aims to explore the effect and potential mechanism of API on liver fibrosis induced by CCl4 in mice. The results indicate that API reduces oxidative stress levels, inhibits hepatic stellate cell (HSC) activation, and exerts anti liver fibrosis effects by regulating the PKM2-HIF-1α pathway. We observed that API alleviated liver tissue pathological damage and collagen deposition in CCl4 induced mouse liver fibrosis model, promoting the recovery of liver function in mice with liver fibrosis. In addition, the API inhibits the transition of Pyruvate kinase isozyme type M2 (PKM2) from dimer to tetramer formation by regulating the EGFR-MEK1/2-ERK1/2 pathway, thereby preventing dimer from entering the nucleus and blocking PKM2-HIF-1α access. This change leads to a decrease in malondialdehyde (MDA) and Catalase (CAT) levels and an increase in glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) levels, as well as total antioxidant capacity (T-AOC) in the liver of liver fibrosis mice. At the same time, API downregulated the expression of α-smooth muscle actin (α-SMA), Vimentin and Desmin in the liver tissue of mice with liver fibrosis, inhibited the activation of HSC, and reduced collagen deposition. These results indicate that API can inhibit HSC activation and alleviate CCl4 induced liver fibrosis by inhibiting the PKM2-HIF-1α pathway and reducing oxidative stress, laying an important foundation for the development and clinical application of API as a novel drug for treating liver fibrosis.

[Research on fault diagnosis of patient monitor based on text mining].

The conventional fault diagnosis of patient monitors heavily relies on manual experience, resulting in low diagnostic efficiency and ineffective utilization of fault maintenance text data. To address these issues, this paper proposes an intelligent fault diagnosis method for patient monitors based on multi-feature text representation, improved bidirectional gate recurrent unit (BiGRU) and attention mechanism. Firstly, the fault text data was preprocessed, and the word vectors containing multiple linguistic features was generated by linguistically-motivated bidirectional encoder representation from Transformer. Then, the bidirectional fault features were extracted and weighted by the improved BiGRU and attention mechanism respectively. Finally, the weighted loss function is used to reduce the impact of class imbalance on the model. To validate the effectiveness of the proposed method, this paper uses the patient monitor fault dataset for verification, and the macro F1 value has achieved 91.11%. The results show that the model built in this study can realize the automatic classification of fault text, and may provide assistant decision support for the intelligent fault diagnosis of the patient monitor in the future.

Exploring the mechanism of Chaihujia Longgu Muli decoction in the treatment of epilepsy in rats based on the RhoA/ROCK signaling pathway.

BACKGROUND: The Chinese herbal formula Chaihujia Longgu Muli Decoction (CD) has a good antiepileptic effect, but its mechanisms remain unclear. Therefore, in this study we explored the molecular mechanisms of CD against epilepsy. METHODS: Twelve-day-old SD rats were randomly divided into a normal group, model group, valproic acid group, and CD high, medium, and low groups. Except for the normal group, the other groups were given an intraperitoneal injection of pentylenetetrazol (PTZ) to establish epilepsy models, and the Racine score was applied for model judgment. After 14 consecutive days of dosing, the Morris water maze test was performed. Then, hippocampal Nissl staining and immunofluorescence staining were performed, and synaptic ultrastructure was observed by transmission electron microscopy (TEM). RhoA/ROCK signaling pathway proteins were detected. RESULTS: In PTZ model rats, the passing times were reduced, and the escape latency was prolonged in the Morris water maze test. Nissl staining showed that some hippocampal neurons swelled and ruptured, Nissl bodies in the cytoplasm were significantly reduced, and neurons were lost. Immunofluorescence detection revealed that the expression of PSD95 and SYP was significantly reduced. Electron microscopy results revealed that the number of synapses in hippocampal neurons was significantly reduced and the postsynaptic membrane length was significantly reduced. Western blot analysis showed that the RhoA/ROCK signaling pathway was activated, while SYP, SPD95, and PTEN expression was significantly decreased. After treatment with CD, neurobehavioral abnormalities and neuronal damage caused by epileptic seizures were improved. CONCLUSION: CD exerted an antiepileptic effect by inhibiting the activation of the RhoA/ROCK signaling pathway.

Melatonin Ameliorates Cisplatin-Induced Renal Tubular Epithelial Cell Damage through PPARα/FAO Regulation.

Previous studies revealed that melatonin ameliorated acute renal injury induced by cisplatin, but the mechanisms remain unclear. Peroxidase proliferative receptor α (PPARα) is considered the major regulator of fatty acid oxidation (FAO), which is an important source of energy for renal tubular epithelial cells. In this study, the aim was to investigate the role of melatonin in cisplatin-induced NRK-52E (rat renal tubular epithelial cell line) cell damage and the underlying mechanisms. We established a cisplatin-stimulated NRK-52E model in vitro. We assessed the levels of apoptotic proteins, including caspase-3, caspase-9, and B-cell lymphoma 2-associated X protein (Bax), as well as PPARα and FAO-related genes (Acadm, Acat1, Acsm2, Acsm3, PGC-1α, Pecr, Bdh2, and Echs1). Furthermore, we detected the effects of miR-21 and PPARα antagonist on the above indicators. We found that melatonin reduced the protein expression levels of caspase-3, caspase-9, and Bax, and increased the expression levels of the PPARα gene and protein and PPARα activity, as well as FAO-related genes, in NRK-52E cells. However, miR-21 mimics and PPARα antagonists partially antagonized the above effects of melatonin. Our data indicated that melatonin could alleviate cisplatin-induced cell damage through the upregulation of PPARα/FAO.

BCREval: a computational method to estimate the bisulfite conversion ratio in WGBS.

BACKGROUND: Whole genome bisulfite sequencing (WGBS) also known as BS-seq has been widely used to measure the methylation of whole genome at single-base resolution. One of the key steps in the assay is converting unmethylated cytosines into thymines (BS conversion). Incomplete conversion of unmethylated cytosines can introduce false positive methylation call. Developing a quick method to evaluate bisulfite conversion ratio (BCR) is benefit for both quality control and data analysis of WGBS. RESULTS: Here we provide a computational method named "BCREval" to estimate the unconverted rate (UCR) by using telomeric repetitive DNA as native spike-in control. We tested the method by using public WGBS data and found that it is very stable and most of BS conversion assays can achieve> 99.5% efficiency. The non-CpG DNA methylation at telomere fits a binomial model and may result from a random process with very low possibility (the ratio < 0.4%). And the comparison between BCREval and Bismark (Krueger and Andrews, Bioinformatics 27:1571-1572, 2011), a widely used BCR evaluator, suggests that our algorithm is much faster and more efficient than the latter. CONCLUSION: Our method is a simple but robust method to QC and speculates BCR for WGBS experiments to make sure it achieves acceptable level. It is faster and more efficient than current tools and can be easily integrated into presented WGBS pipelines.

The nucleoside diphosphate kinase NDK-1/NME1 promotes phagocytosis in concert with DYN-1/Dynamin.

Phagocytosis of various targets, such as apoptotic cells or opsonized pathogens, by macrophages is coordinated by a complex signaling network initiated by distinct phagocytic receptors. Despite the different initial signaling pathways, each pathway ends up regulating the actin cytoskeletal network, phagosome formation and closure, and phagosome maturation leading to degradation of the engulfed particle. Herein, we describe a new phagocytic function for the nucleoside diphosphate kinase 1 (NDK-1), the nematode counterpart of the first identified metastasis inhibitor NM23-H1 (nonmetastatic clone number 23) nonmetastatic clone number 23 or nonmetastatic isoform 1 (NME1). We reveal by coimmunoprecipitation, Duolink proximity ligation assay, and mass spectrometry that NDK-1/NME1 works in a complex with DYN-1/Dynamin (Caenorhabditis elegans/human homolog proteins), which is essential for engulfment and phagosome maturation. Time-lapse microscopy shows that NDK-1 is expressed on phagosomal surfaces during cell corpse clearance in the same time window as DYN-1. Silencing of NM23-M1 in mouse bone marrow-derived macrophages resulted in decreased phagocytosis of apoptotic thymocytes. In human macrophages, NM23-H1 and Dynamin are corecruited at sites of phagosome formation in F-actin-rich cups. In addition, NM23-H1 was required for efficient phagocytosis. Together, our data demonstrate that NDK-1/NME1 is an evolutionarily conserved element of successful phagocytosis.-Farkas, Z., Petric, M., Liu, X., Herit, F., Rajnavölgyi, É., Szondy, Z., Budai, Z., Orbán, T. I., Sándor, S., Mehta, A., Bajtay, Z., Kovács, T., Jung, S. Y., Afaq Shakir, M., Qin, J., Zhou, Z., Niedergang, F., Boissan, M., Takács-Vellai, K. The nucleoside diphosphate kinase NDK-1/NME1 promotes phagocytosis in concert with DYN-1/dynamin.

MKP2 inhibits TGF-ß1-induced epithelial-to-mesenchymal transition in renal tubular epithelial cells through a JNK-dependent pathway.

Epithelial-to-mesenchymal transition (EMT) is a phenotypic conversion that plays a crucial role in renal fibrosis leading to chronic renal failure. Mitogen-activated protein kinase phosphatase 2 (MKP2) is a member of the dual-specificity MKPs that regulate the MAP kinase pathway involved in transforming growth factor-ß1 (TGF-ß1)-induced EMT. However, the function of MKP2 in the regulation of EMT and the underlying mechanisms are still largely unknown. In the present study, we detected the expression of MKP2 in an animal model of renal fibrosis and evaluated the potential role of MKP2 in tubular EMT induced by TGF-ß1. We found that the expression of MKP2 was up-regulated in the tubular epithelial of unilateral ureter obstruction rats. Meanwhile, we also demonstrated that TGF-ß1 up-regulated MKP2 expression in NRK-52E cells during their EMT phenotype acquisition. Importantly, overexpression of MKP2 inhibited c-Jun amino terminal kinase (JNK) signaling and partially reversed EMT induced by TGF-ß1. Moreover, reducing MKP2 expression enhanced JNK phosphorylation, promoted the E-cadherin suppression and induced α-SMA expression and fibronectin secretion in response to TGF-ß1, which could be rescued by a JNK inhibitor. These results provide the first evidence that MKP2 is a negative feedback molecule induced by TGF-ß1, and MKP2 overexpression inhibits TGF-ß1-induced EMT through the JNK signaling pathway. MKP2 could be a promising target to be used in gene therapy for renal fibrosis.

Semaphorin-3A and Netrin-1 predict the development of kidney injury in children with congenital hydronephrosis.

Congenital obstructive nephropathy is amongst the main causes of chronic renal failure in children. Early diagnosis and initiation of the treatment will delay progressive renal tubular atrophy and interstitial fibrosis with the loss of nephrons. The aim of this study was to evaluate whether urinary (u) semaphorin-3A (SEMA-3A) and Netrin-1 may be potential biomarkers in children with congenital hydronephrosis due to ureteropelvic junction obstruction (UPJO). The study consisted of 42 children with severe hydronephrosis who needed surgery and two control groups (Control One: 42 children with mild, non-obstructive hydronephrosis; Control Two: 44 healthy children). All children had normal renal function. Urinary semaphorin-3A and Netrin-1 levels were measured in different groups using immunoenzymatic ELISA commercial kits. Compared with Control One and Control Two groups, the preoperative median uSEMA-3A/creatinine (cr.) and uNetrin-1/cr. levels increased significantly in the children with severe hydronephrosis (p < .01). One month after surgery, uSEMA-3A/cr. and uNetrin-1/cr. levels had decreased significantly in the children with severe hydronephrosis (p < .01), but were still higher than those in both control groups (p < .05). Receiver operator characteristic (ROC) analyses revealed a good diagnostic profile for uSEMA-3A and uNetrin-1 in terms of identifying children with a differential renal function of <40% [area under the curve (AUC) 0.825 and 0.745, respectively]. Our results indicate that increased concentrations of uSEMA-3A and uNetrin-1 are found in urine from children with severe hydronephrosis and that their concentrations are related to the degree of obstruction.

MiR-1246 Promotes LPS-Induced Inflammatory Injury in Chondrogenic Cells ATDC5 by Targeting HNF4γ.

BACKGROUND/AIMS: Osteoarthritis (OA) is a common inflammatory joint disease. miRNAs are associated with OA and functionally implicated in the pathogenesis of the disease. In the present study, we investigated the role of miR-1246 in the lipopolysaccharide (LPS)-induced inflammatory injury of ATDC5 cells. METHODS: ATDC5 cells were cultured and treated with LPS in a series of concentration (0, 1, 5, and 10 µg/ml) for 5 h. The cells were transfected with miR-1246-mimic, inhibitor, si-HNF4γ or negative control, then were assessed for cell viability using CCK8 assay, apoptosis by flow-cytometry and expressions of miR-1246 and pro-inflammatory cytokines by qRT-PCR and western blot analysis. RESULTS: Cell viability was significantly reduced and cell apoptosis was added in ATDC5 cells injured with LPS at the dosage of 5 and 10 µg/ml. Relative mRNA expressions of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8 and TNF-α) were significantly increased. miR-1246 was up-regulated in ATDC5 cells treated with LPS. Moreover, miR-1246 overexpression aggravated LPS-induced decrease in cell viability, increase in apoptosis and overproduction of pro-inflammatory factors. mRNA and protein expressions of HNF4γ were significantly suppressed in cells transfected with miR-124-mimic. Further, miR-1246 knockdown alleviated LPS-induced inflammatory injury by up-regulating the expression of HNF4γ and activation of PI3K/AKT and JAK/STAT pathways. CONCLUSIONS: Suppression of miR-1246 alleviated LPS-induced inflammatory injury in chondrogenic ADTC5 cells by up-regulation of HNF4γ and activation of PI3K/AKT and JAK/STAT pathways. The findings of this study will provide a novel viewpoint regarding miR-1246 target for clinical.

The potential application of strategic released apigenin from polymeric carrier in pulmonary fibrosis.

AIM: The capability of reducing fibrotic and inflammatory responses in lung tissues represents a gold standard for evaluating the efficacy of therapeutic interventions for treating idiopathic pulmonary fibrosis (IPF). A wide variety of therapeutic strategies have been employed in clinic to treat PF, but limited success has been obtained. Apigenin (4, 5, 7-trihydroxyflavone) is a member of flavonoid family that exerts anti-inflammatory and anti-fibrosis effects. In this study, we explore the potential therapeutic effect of apigenin in lung fibrosis. MATERIALS AND METHODS: Apigenin was employed to treat IPF in a bleomycin-induced PF rat model. Apigenin was loaded onto a biodegradable polymer carrier (nanoparticle, NP) to improve its bio-solubility and bio-availability. The properties (e.g. size, apigenin loading and release profile) of the apigenin loaded polymer carrier were well-characterized. In vitro study was performed to assess the impact of apigenin on pulmonary cell viability, growth, as well as inflammatory and pro-fibrosis responses in pulmonary cells. The impact of apigenin on the production of inflammatory cytokines (e.g. TGF-ß, TNF-α) and pro-fibrosis factors in bronchoalveolar lavage fluid and pulmonary cells from lung tissues was also investigated. RESULTS: Our results showed, apigenin has anti-fibrosis effect by inhibition fibrosis related cytokines expression. And compared with apigenin in soluble form, the strategic release of apigenin is more effective in inhibiting pulmonary fibrosis and inflammation. CONCLUSION: Our finding suggested that apigenin loaded on polymeric carrier might be an effective treatment for pulmonary fibrosis patients.

Urinary heme oxygenase-1 as a potential biomarker for early diabetic nephropathy.

BACKGROUND: Our previous study showed that increases of urinary heme oxygenase-1 (uHO-1) could be a potential biomarker indicating evaluating intrarenal oxidative damage in obstructive nephropathy. Activation of oxidative stress is an important mediator of diabetic nephropathy (DN). The aim of this study was to investigate the clinical implications of uHO-1 levels in patients with type 2 diabetes. METHODS: Eighty-four type 2 diabetic patients with normoalbuminuria (n=28), microalbuminuria (n=28), and macroalbuminuria (n=28) were included in this study. Control samples were collected from healthy volunteers (n=28) who had normal albuminuria and renal function. Urine HO-1 levels were evaluated by enzyme-linked immunosorbent assay. RESULTS: Urinary HO-1/creatinine (cr.) levels were significantly elevated in diabetic patients with microalbuminuria and macroalbuminuria compared to those in diabetic patients with normoalbuminuria (P<0.001) and control subjects (all P<0.001). In diabetic patients with normoalbuminuria, uHO-1/cr. levels were also higher than those in controls (P<0.001). Multivariate regression analyses revealed that uHO-1/cr. levels were positively correlated to urinary albumin/creatinine ratio and inversely correlated to glomerular filtration rate. Receiver operating characteristic (ROC) curve analysis of uHO-1/cr. levels for early diagnosis and detection of DN revealed that the cut-off value of uHO-1/cr. was 4.59 ng/mg (sensitivity 75%, specificity 78.6%). CONCLUSIONS: The findings of this study indicate that increases of urine HO-1 levels can be detected in patients with type 2 diabetes before the onset of significant albuminuria, and associated with renal derangement in patients with established diabetic nephropathy. Urinary HO-1 may be used as an early biomarker for diabetic renal injury.

Pirfenidone suppresses MAPK signalling pathway to reverse epithelial-mesenchymal transition and renal fibrosis.

AIM: Recent studies indicate that pirfenidone (PFD) may have anti-fibrotic effects in many tissues, but the potential molecular mechanism remains unknown. The purpose of this study is to investigate the potential effects of PFD on epithelial-to-mesenchymal transition (EMT) and renal fibrosis in a unilateral ureteral obstruction (UUO) rat model and the involved molecular mechanism related to cultured human renal proximal tubular epithelial cells (HK-2). METHODS: Sixty rats were randomly divided into three groups: sham-operated, vehicle-treated UUO, and PFD-treated UUO. Kidney specimens were collected at day 7 or 14 after UUO. PFD treatment was also performed for human HK-2. The tubulointerstitial injury, interstitial collagen deposition, and expression of type I and III collagen, α-SMA, S100A4, fibronection and E-cadherin were assessed. In addition, extracellular signal regulated kinase (ERK1/2), p38 MAPK (p38), and c-Jun N-terminal kinase/stress-activated protein kinase (JNK) were also detected. RESULTS: In vitro, PFD significantly attenuated TGF-ß1-induced EMT and extracellular matrix (ECM) synthesis, as determined by reducing expression of α-SMA, type I and III collagen, S100A4, fibronection, and increased expression of E-cadherin. PFD treatment attenuated TGF-ß1-induced up-regulation of phosphorylation of ERK1/2, p38 and JNK. In vivo, PFD reduced the degree of tubulointerstitial injury and renal fibrosis, which was associated with reduced expression of TGF-ß1, type III collagen, α-SMA, S100A4, fibronection, and increased expression of E-cadherin. CONCLUSION: These results suggest that pirfenidone is able to attenuate EMT and fibrosis in vivo and in vitro through antagonizing the MAPK pathway, providing a potential treatment to alleviate renal tubulointerstitial fibrosis.

Decreased long noncoding RNA MIR31HG is correlated with poor prognosis and contributes to cell proliferation in gastric cancer.

Long noncoding RNAs (lncRNAs) are emerging as key regulators governing fundamental biological processes, and their disorder expression involves in the development of several human cancers. MIR31HG, an lncRNA located in 9p21.3 and 2166 bp in length, has been found to be upregulated in breast cancer and contributes to cell proliferation and invasion. However, the expression pattern and biological function of MIR31HG in gastric cancer are still not well documented. In this study, we found that MIR31HG expression is decreased in gastric cancer tissues and associated with larger tumor size and advanced pathological stage. Patients with lower MIR31HG expression had a relatively poor prognosis. Furthermore, ectopic over-expression of MIR31HG could inhibit gastric cancer (GC) cell proliferation both in vitro and in vivo, while knockdown of MIR31HG by small interfering RNA (siRNA) promoted cell proliferation in GC cells partly via regulating E2F1 and p21 expression. Our findings present that decreased MIR31HG is involved in GC development and could be identified as a poor prognostic biomarker in GC patients.

Brain-derived neurotrophic factor (BDNF)-induced mitochondrial motility arrest and presynaptic docking contribute to BDNF-enhanced synaptic transmission.

Appropriate mitochondrial transport and distribution are essential for neurons because of the high energy and Ca(2+) buffering requirements at synapses. Brain-derived neurotrophic factor (BDNF) plays an essential role in regulating synaptic transmission and plasticity. However, whether and how BDNF can regulate mitochondrial transport and distribution are still unclear. Here, we find that in cultured hippocampal neurons, application of BDNF for 15 min decreased the percentage of moving mitochondria in axons, a process dependent on the activation of the TrkB receptor and its downstream PI3K and phospholipase-Cγ signaling pathways. Moreover, the BDNF-induced mitochondrial stopping requires the activation of transient receptor potential canonical 3 and 6 (TRPC3 and TRPC6) channels and elevated intracellular Ca(2+) levels. The Ca(2+) sensor Miro1 plays an important role in this process. Finally, the BDNF-induced mitochondrial stopping leads to the accumulation of more mitochondria at presynaptic sites. Mutant Miro1 lacking the ability to bind Ca(2+) prevents BDNF-induced mitochondrial presynaptic accumulation and synaptic transmission, suggesting that Miro1-mediated mitochondrial motility is involved in BDNF-induced mitochondrial presynaptic docking and neurotransmission. Together, these data suggest that mitochondrial transport and distribution play essential roles in BDNF-mediated synaptic transmission.

Blocking GSK3ß-mediated dynamin1 phosphorylation enhances BDNF-dependent TrkB endocytosis and the protective effects of BDNF in neuronal and mouse models of Alzheimer's disease.

Endocytosis of tropomyosin related kinase B (TrkB) receptors has critical roles in brain-derived neurotrophic factor (BDNF) mediated signal transduction and biological function, however the mechanism that is governing TrkB endocytosis is still not completely understood. In this study, we showed that GSK3ß, a key kinase in neuronal development and survival, could regulate TrkB endocytosis through phosphorylating dynamin1 (Dyn1) but not dynamin2 (Dyn2). Moreover, we found that beta-amyloid (Aß) oligomer exposure could impair BDNF-dependent TrkB endocytosis and Akt activation through enhancing GSK3ß activity in cultured hippocampal neurons, which suggested that BDNF-induced TrkB endocytosis and the subsequent signaling were impaired in neuronal model of Alzheimer's disease (AD). Notably, we found that inhibiting GSK3ß phosphorylating Dyn1 by using TAT-Dyn1SpS could rescue the impaired TrkB endocytosis and Akt activation upon BDNF stimuli under Aß exposure. Finally, TAT-Dyn1SpS could facilitate BDNF-mediated neuronal survival and cognitive enhancement in mouse models of AD. These results clarified a role of GSK3ß in BDNF-dependent TrkB endocytosis and the subsequent signaling, and provided a potential new strategy by inhibiting GSK3ß-induced Dyn1 phosphorylation for AD treatment.

Decreased long noncoding RNA SPRY4-IT1 contributing to gastric cancer cell metastasis partly via affecting epithelial-mesenchymal transition.

BACKGROUND: Long noncoding RNAs (lncRNAs) are emerging as key regulators governing fundamental biological processes, and their disorder expression involves in tumorigenesis. SPRY4-IT1 (SPRY4 intronic transcript 1), a lncRNA derived from an intron within SPRY4 gene, involves in multiple cancers development. However, the expression pattern and biological function of SPRY4-IT1 in gastric cancer is still not well documented. Hence, we carried out the present study to investigate the potential role of SPRY4-IT1 in gastric carcinogenesis. METHODS: QRT-PCR was performed to detect the expression of SPRY4-IT1 in 61 pairs of gastric cancer samples. Over-expression and RNA interference (RNAi) approaches were used to investigate the biological functions of SPRY4-IT1. The effect of SPRY4-IT1 on proliferation was evaluated by MTT and colony formation assays. Gastric cancer cells transfected with pCDNA-SPRY4-IT1 were injected into nude mice to study the effect of SPRY4-IT1 on tumorigenesis and metastasis in vivo. Protein levels of SPRY4-IT1 targets were determined by western blot or fluorescence immunohistochemistry. ChIP assays were performed to investigate the effect of DNMT1 on SPRY4-IT1 expression. Differences between groups were tested for significance using Student's t test (two-tailed). RESULTS: SPRY4-IT1 expression is decreased in gastric cancer tissues and associated with larger tumor size, advanced pathological stage, deeper depth of invasion and lymphatic metastasis. Patients with lower SPRY4-IT1 expression had a relatively poor prognosis. DNA methylation may be a key factor in controlling the SPRY4-IT1 expression. Furthermore, SPRY4-IT1 contributed to gastric cancer cells metastasis might partly via regulating epithelial-mesenchymal transition (EMT) process. CONCLUSION: Low expression of SPRY4-IT1 is involved in progression and metastasis of gastric cancer and may represent a novel biomarker of poor prognosis in patients with gastric cancer.

MicroRNA-200b stimulates tumour growth in TGFBR2-null colorectal cancers by negatively regulating p27/kip1.

Colorectal cancer (CRC) remains the most common malignancy worldwide. TGF-ß1 is often overexpressed in late stages of colorectal carcinogenesis and promotes tumour growth and metastasis. Several reports have verified that the loss of functional TGFBRII expression contributed to escape the tumour suppressor activity of TGF-ß1 and that the epithelial-to-mesenchymal transition (EMT) responded to TGF-ß1 involved in tumour invasion and metastasis. However, the mechanisms by which TGF-ß1 confers a growth advantage to TGFBRII-null colorectal cancer cells have not been elucidated. MicroRNAs (miRNAs) are post-transcriptional inhibitory regulators of gene expression that act by directly binding complementary mRNA and are key determinants of cancer initiation and progression. In this study, we revealed a role for miR-200b in colorectal cancer. MiR-200b was highly expressed in TGFBRII-null tumour tissues and colorectal cancer cell lines and positively correlated with cell proliferation in tumour tissues and cell lines. In contrast, decreasing the miR-200b level in TGFBRII-null cells suppressed cell proliferation and cell cycle progression. Furthermore, in vivo studies also suggested a stimulating effect of miR-200b on TGFBRII-null cell-derived xenografts. CDKN1B (p27/kip1) and RND3 (RhoE) have miR-200b binding sequences within their 3' untranslated regions and were confirmed to be direct targets of miR-200b using fluorescent reporter assays. Meanwhile, CDKN1B (p27/kip1) played a role in miR-200b-stimulated TGFBR-null CRC. This study suggests that miR-200b plays a tumour-promoting role by targeting CDKN1B (p27/kip1) in CRCs.

Downregulation of BRAF activated non-coding RNA is associated with poor prognosis for non-small cell lung cancer and promotes metastasis by affecting epithelial-mesenchymal transition.

BACKGROUND: Recent evidence indicates that long noncoding RNAs (lncRNAs) play a critical role in the regulation of cellular processes, such as differentiation, proliferation and metastasis. These lncRNAs are found to be dysregulated in a variety of cancers. BRAF activated non-coding RNA (BANCR) is a 693-bp transcript on chromosome 9 with a potential functional role in melanoma cell migration. The clinical significance of BANCR, and its' molecular mechanisms controlling cancer cell migration and metastasis are unclear. METHODS: Expression of BANCR was analyzed in 113 non-small cell lung cancer (NSCLC) tissues and seven NSCLC cell lines using quantitative polymerase chain reaction (qPCR) assays. Gain and loss of function approaches were used to investigate the biological role of BANCR in NSCLC cells. The effects of BANCR on cell viability were evaluated by MTT and colony formation assays. Apoptosis was evaluated by Hoechst staining and flow cytometry. Nude mice were used to examine the effects of BANCR on tumor cell metastasis in vivo. Protein levels of BANCR targets were determined by western blotting and fluorescent immunohistochemistry. RESULTS: BANCR expression was significantly decreased in 113 NSCLC tumor tissues compared with normal tissues. Additionally, reduced BANCR expression was associated with larger tumor size, advanced pathological stage, metastasis distance, and shorter overall survival of NSCLC patients. Reduced BANCR expression was found to be an independent prognostic factor for NSCLC. Histone deacetylation was involved in the downregulation of BANCR in NSCLC cells. Ectopic expression of BANCR impaired cell viability and invasion, leading to the inhibition of metastasis in vitro and in vivo. However, knockdown of BANCR expression promoted cell migration and invasion in vitro. Overexpression of BANCR was found to play a key role in epithelial-mesenchymal transition (EMT) through the regulation of E-cadherin, N-cadherin and Vimentin expression. CONCLUSION: We determined that BANCR actively functions as a regulator of EMT during NSCLC metastasis, suggesting that BANCR could be a biomarker for poor prognosis of NSCLC.

Lnc RNA HOTAIR functions as a competing endogenous RNA to regulate HER2 expression by sponging miR-331-3p in gastric cancer.

BACKGROUND: Accumulating evidence indicates that the long non-coding RNA HOTAIR plays a critical role in cancer progression and metastasis. However, the overall biological role and clinical significance of HOTAIR in gastric carcinogenesis remains largely unknown. METHODS: HOTAIR expression was measured in 78 paired cancerous and noncancerous tissue samples by real-time PCR. The effects of HOTAIR on gastric cancer cells were studied by overexpression and RNA interference approaches in vitro and in vivo. Insights of the mechanism of competitive endogenous RNAs (ceRNAs) were gained from bioinformatic analysis, luciferase assays and RNA binding protein immunoprecipitation (RIP). The positive HOTAIR/HER2 interaction was identified and verified by immunohistochemistry assay and bivariate correlation analysis. RESULTS: HOTAIR upregulation was associated with larger tumor size, advanced pathological stage and extensive metastasis, and also correlated with shorter overall survival of gastric cancer patients. Furthermore, HOTAIR overexpression promoted the proliferation, migration and invasion of gastric carcinoma cells, while HOTAIR depletion inhibited both cell invasion and cell viability, and induced growth arrest in vitro and in vivo. In particular, HOTAIR may act as a ceRNA, effectively becoming a sink for miR-331-3p, thereby modulating the derepression of HER2 and imposing an additional level of post-transcriptional regulation. Finally, the positive HOTAIR/HER2 correlation was significantly associated with advanced gastric cancers. CONCLUSIONS: HOTAIR overexpression represents a biomarker of poor prognosis in gastric cancer, and may confer malignant phenotype to tumor cells. The ceRNA regulatory network involving HOTAIR and the positive interaction between HOTAIR and HER2 may contribute to a better understanding of gastric cancer pathogenesis and facilitate the development of lncRNA-directed diagnostics and therapeutics against this disease.

Downregulated long noncoding RNA MEG3 is associated with poor prognosis and promotes cell proliferation in gastric cancer.

Long noncoding RNAs (lncRNAs) have emerged recently as major players in governing fundamental biological processes, and many of which are altered in expression and likely to have a functional role in tumorigenesis. Maternally expressed gene 3 (MEG3) is an imprinted gene located at 14q32 that encodes a lncRNA associated with various human cancers. However, its biological role and clinical significance in gastric cancer development and progression are unknown. In this study, to investigate the lncRNA MEG3 expression in gastric cancer, quantitative reverse-transcription polymerase chain reaction was conducted. We found that MEG3 levels were markedly decreased in gastric cancer tissues compared with adjacent normal tissues. Its expression level was significantly correlated with TNM stages, depth of invasion, and tumor size. Moreover, patients with low levels of MEG3 expression had a relatively poor prognosis. Furthermore, knockdown of MEG3 expression by siRNA could promote cell proliferation, while ectopic expression of MEG3 inhibited cell proliferation, promoted cell apoptosis, and modulated p53 expression in gastric cancer cell lines. By 5-aza-CdR treatment, we also observed that MEG3 expression can be modulated by DNA methylation. Our findings present that MEG3 downexpression can be identified as a poor prognostic biomarker in gastric cancer and regulate cell proliferation and apoptosis in vitro.