Human telomerase reverse transcriptase is a novel target of Hippo-YAP pathway.

Telomerase plays a pivotal role in tumorigenesis by maintaining telomere homeostasis, a hallmark of cancer. However, the mechanisms by which telomerase is reactivated or upregulated during tumorigenesis remain incompletely understood. Here, we report that the Hippo pathway effector Yes-associated protein (YAP) regulates the expression of human telomerase reverse transcriptase (hTERT). Ectopic expression or physiological activation of YAP increases hTERT expression, whereas knockdown of YAP decreases the expression of hTERT. YAP binds to the hTERT promoter through interaction with the TEA domain family transcription factors and activates hTERT transcription. Furthermore, sustained YAP hyperactivation promotes telomerase activity and extends telomere length, with increased hTERT expression. In addition, we show that hTERT expression is positively correlated with YAP activation in human liver cancer tissues. Together, our results demonstrate that YAP promotes hTERT expression, which could contribute to tumor progression.

Disease managing capacities and mechanisms of host effects of lactic acid bacteria.

Consumption of lactic acid bacteria (LAB) has been suggested to confer health-promoting effects on the host. However, effects of LABs have been reported to be species- and strain-specific and the mechanisms involved are subjects of discussion. Here, the possible mechanisms by which LABs induce antipathogenic, gut barrier enhancing and immune modulating effects in consumers are reviewed. Specific strains for which it has been proven that health is improved by these mechanisms are discussed. However, most strains probably act via several or combinations of mechanisms depending on which effector molecules they express. Current insight is that these effector molecules are either present on the cell wall of LAB or are excreted. These molecules are reviewed as well as the ligand binding receptors in the host. Also postbiotics are discussed. Finally, we provide an overview of the efficacy of LABs in combating infections caused by Helicobacter pylori, Salmonella, Escherichia coli, Streptococcus pneumoniae, and influenza virus, in controlling gut inflammatory diseases, in managing allergic disorders, and in alleviating cancer.

Functions and Mechanisms of Long Noncoding RNAs in Ovarian Cancer.

Long noncoding RNAs (lncRNAs) are longer than 200-nucleotide, noncoding transcripts in length, have a variety of biological functions, and are closely associated with tumor development. Ovarian cancer, as 1 of the 3 common gynecological malignancies, is the leading cause of death in women with gynecological malignant tumor. In this study, a review of the literature found that lncRNAs H19, LSINCT5, and XIST have a close relationship to the development of ovarian cancer occurrence, growth, invasion, and metastasis, and they can promote ovarian cancer cell proliferation. Hence, in this article, the progress of above-mentioned 3 kinds of lncRNAs in ovarian cancer was reviewed and designed to help in the diagnosis, treatment, and prognosis of ovarian cancer.

Suppression of dust mite allergy by mucosal delivery of a hypoallergenic derivative in a mouse model.

Allergic asthma caused by house dust mite (HDM) is becoming a public health problem. Specific immunotherapy is considered to be the only curative treatment, but it is always associated with IgE-mediated side effects in the therapy process. A few studies showed that the disruption of allergen IgE epitopes could reduce IgE reactivity and thus reduce allergenic activity. In this study, a hypoallergenic derivative of the major HDM allergen Der p2 was constructed by genetic engineering. This derivative was confirmed to have a considerably reduced IgE reactivity compared with Der p2. For its application in vivo, recombinant Lactococcus lactis (LL-DM) was engineered to deliver the Der p2 derivative to the intestinal mucosal surface. Oral administration of LL-DM significantly alleviated Der p2-induced airway inflammation, as shown by reduced inflammatory infiltration and a reduction in Th2 cytokines in bronchoalveolar lavage. This protective effect was associated with an up-regulation of specific IgG2a and a decrease in IL-4 level in the spleen which may affect specific IgE response. Moreover, the levels of regulatory T cells in the mesenteric lymph nodes and spleen were markedly increased in mice fed with LL-DM, suggesting that LL-DM can inhibit allergic responses via the induction of regulatory T cell. Our results indicate that the Der p2 derivative is a promising therapeutic molecule for specific immunotherapy and recombinant lactic acid bacteria could be developed as a promising treatment or prevention strategy for allergic diseases.

Modulation of peanut-induced allergic immune responses by oral lactic acid bacteria-based vaccines in mice.

Peanut allergy (PNA) has becoming a non-negligible health concern worldwide. Thus far, allergen-specific immunotherapy aimed at inducing mucosal tolerance has widely been regarded as a major management strategy for PNA. The safety profiles and the intrinsic probiotic properties of lactic acid bacteria (LAB) render them attractive delivery vehicles for mucosal vaccines. In the present study, we exploited genetically modified Lactococcus lactis to produce peanut allergen Ara h 2 via different protein-targeting systems and their immunomodulatory potency for allergic immune responses in mice were investigated. By comparison with the strain expressing the cytoplasmic form of Ara h 2 (LL1), the strains expressing the secreted and anchored forms of Ara h 2 (LL2 and LL3) were more potent in redirecting a Th2-polarized to a non-allergic Th1 immune responses. Induction of SIgA and regulatory T cells were also observed at the local levels by orally administration of recombinant L. lactis. Our results indicate that allergen-producing L. lactis strains modulated allergic immune responses and may be developed as promising mucosal vaccines for managing allergic diseases.

Promotion of BST2 expression by the transcription factor IRF6 affects the progression of endometriosis.

Background: Endometriosis (EM) is a benign, multifactorial, immune-mediated inflammatory disease that is characterized by persistent activation of the NF-κB signaling pathway and some features of malignancies, such as proliferation and lymphangiogenesis. To date, the pathogenesis of EM is still unclear. In this study, we investigated whether BST2 plays a role in the development of EM. Methods: Bioinformatic analysis was performed with data from public databases to identify potential candidate targets for drug treatment. Experiments were conducted at the cell, tissue, and mouse EM model levels to characterize the aberrant expression patterns, molecular mechanisms, biological behaviors of endometriosis as well as treatment outcomes. Results: BST2 was significantly upregulated in ectopic endometrial tissues and cells compared with control samples. Functional studies indicated that BST2 promoted proliferation, migration, and lymphangiogenesis and inhibited apoptosis in vitro and in vivo. The transcription factor (TF) IRF6 induced high BST2 expression by directly binding the BST2 promoter. The underlying mechanism by which BST2 functions in EM was closely related to the canonical NF-κB signaling pathway. New lymphatic vessels may serve as a channel for the infiltration of immune cells into the endometriotic microenvironment; these immune cells further produce the proinflammatory cytokine IL-1ß, which in turn further activates the NF-κB pathway to promote lymphangiogenesis in endometriosis. Conclusion: Taken together, our findings provide novel insight into the mechanism by which BST2 participates in a feedback loop with the NF-κB signaling pathway and reveal a novel biomarker and potential therapeutic target for endometriosis.

Rapid quantification of 50 fatty acids in small amounts of biological samples for population molecular phenotyping.

Efficient quantification of fatty-acid (FA) composition (fatty-acidome) in biological samples is crucial for understanding physiology and pathophysiology in large population cohorts. Here, we report a rapid GC-FID/MS method for simultaneous quantification of all FAs in numerous biological matrices. Within eight minutes, this method enabled simultaneous quantification of 50 FAs as fatty-acid methyl esters (FAMEs) in femtomole levels following the efficient transformation of FAs in all lipids including FFAs, cholesterol-esters, glycerides, phospholipids and sphingolipids. The method showed satisfactory inter-day and intra-day precision, stability and linearity (R2 > 0.994) within a concentration range of 2-3 orders of magnitude. FAs were then quantified in typical multiple biological matrices including human biofluids (urine, plasma) and cells, animal intestinal content and tissue samples. We also established a quantitative structure-retention relationship (QSRR) for analytes to accurately predict their retention time and aid their reliable identification. We further developed a novel no-additive retention index (NARI) with endogenous FAMEs reducing inter-batch variations to 15 seconds; such NARI performed better than the alkanes-based classical RI, making meta-analysis possible for data obtained from different batches and platforms. Collectively, this provides an inexpensive high-throughput analytical system for quantitative phenotyping of all FAs in 8-minutes multiple biological matrices in large cohort studies of pathophysiological effects.

Dickkopf-1 expression is a novel prognostic marker for gastric cancer.

AIM: To investigate the involvement of Dickkopf-1 expression in gastric cancer. METHODS: Dickkopf-1 mRNA and protein expression were determined by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and immunohistochemistry in specimens of primary cancer and their adjacent noncancerous tissues in gastric cancer patients. RESULTS: Dickkopf-1 mRNA and protein expression levels were both significantly upregulated in gastric cancer lesions compared with adjacent noncancerous tissues. Its positive expression was correlated with depth of invasion, vessel invasion, lymph node and distant metastasis, and TNM stage of tumors. Additionally, in stages I, II, and III gastric cancers, the 5- year survival rate of patients with a high expression of Dickkopf-1 was significantly lower than that in patients with low expression. In stage IV, Dickkopf-1 expression did not correlate with the 5-year survival rate. Further multivariate analysis suggested that the up-regulation of Dickkopf-1 was an independent prognostic indicator for gastric cancer. CONCLUSION: A subset of cases with gastric cancer revealed the up-regulation of Dickkopf-1, which was associated with a progressive pathological feature and an aggressive clinical course. Therefore, Dickkopf-1 expression may be predictor for poor prognosis in patients with gastric cancer. This is the first report describing the involvement of Dickkopf-1 in gastric cancer.

Finite-Time L2-Gain Asynchronous Control for Continuous-Time Positive Hidden Markov Jump Systems via T-S Fuzzy Model Approach.

This article investigates the finite-time asynchronous control problem for continuous-time positive hidden Markov jump systems (HMJSs) by using the Takagi-Sugeno fuzzy model method. Different from the existing methods, the Markov jump systems under consideration are considered with the hidden Markov model in the continuous-time case, that is, the Markov model consists of the hidden state and the observed state. We aim to derive a suitable controller that depends on the observation mode which makes the closed-loop fuzzy HMJSs be stochastically finite-time bounded and positive, and fulfill the given L2 performance index. Applying the stochastic Lyapunov-Krasovskii functional (SLKF) methods, we establish sufficient conditions to obtain the finite-time state-feedback controller. Finally, a Lotka-Volterra population model is used to show the feasibility and validity of the main results.

An update on colorectal cancer microenvironment, epigenetic and immunotherapy.

Colorectal cancer (CRC) is considered as the second most common cancer worldwide. For the past few years, the role of immunotherapy has been extensively studied and it has been demonstrated that its related approaches, such as programmed death-1 (PD-1) inhibitors, are promising. In addition to identifying molecular characteristics of tumor cells, recent studies are mainly focused on the profiling of tumor microenvironment. Dissecting immune status of a tumor is interesting, since development of a tumor is associated with deficiencies relate to immune defense, immune surveillance and immune hemostasis. In this review, we discuss main obstacles of immunotherapy including immunosuppressive niche and low immunogenicity of CRC as well as reviewing current achievements in immunotherapy.

The impact of oligosaccharide content, glycosidic linkages and lactose content of galacto-oligosaccharides (GOS) on the expression of mucus-related genes in goblet cells.

Galacto-oligosaccharides (GOS) have been reported to modulate the function of intestinal goblet cells and to improve mucus barrier function. However, GOS is available in many structurally different compositions and it is unknown how GOS structural diversity impacts this modulation of goblet cells. This study aims to investigate the effects of oligosaccharide content and glycosidic linkages of GOS on expression of genes associated with the secretory function of goblet cells. To investigate the effect of oligosaccharide content, LS174T cells were incubated with (ß1 → 4)GOS of variable transgalactosylated oligosaccharides and lactose (Lac) composition. To investigate the effect of glycosidic linkages, we compared the effects of (ß1 → 4)GOS with (ß1 → 3)GOS, and with a mixture of α-linked oligosaccharides (lactose-derived oligosaccharides-LDO). The changes in mRNA expression of mucus-related genes were assessed by RT-PCR. GOS containing Lac significantly enhanced the expression of MUC2, TFF3 and RETNLB but not of Golgi sulfotransferases genes. In contrast, GOS without Lac did not impact these genes. Lac alone significantly enhanced MUC2, TFF3, RETNLB, CHST5, and GAL3ST2 genes suggesting that Lac might be responsible for goblet cell modulation in (ß1 → 4)GOS preparations. (ß1 → 3)GOS induced the expression of MUC2 and TFF3, and downregulated the RETNLB gene. Compared with the (ß1 → 3) and GOS (ß1 → 4)GOS, the α-linked LDO significantly upregulated the expression MUC2, TFF3, RETNLB and the Golgi sulfotransferases genes. We identify structural features of GOS that contribute to enhanced mucus integrity. Our study might lead to better GOS formulations for foods to prevent or treat different types of intestinal disorders.

Protective effects of lactic acid bacteria on gut epithelial barrier dysfunction are Toll like receptor 2 and protein kinase C dependent.

Lactic acid bacteria (LAB) are recognized for support of host gut homeostasis but the precise mechanisms remain to be identified. LABs interact with Toll-like receptors (TLRs) which might stimulate barrier function of gut epithelial cells. We previously identified six TLR2-signalling LAB strains. As TLR2 is involved in barrier-function enhancement in gut-epithelium, the epithelial barrier-protective effect of these TLR2-signalling strains was studied by using T84 human colorectal cancer cell monolayer as an in vitro gut epithelial barrier model. The protein kinase C (PKC) dependent barrier disruptor A23187 and mitogen-activated protein kinase dependent barrier stressor deoxynivalenol were tested to determine which pathways LAB influenced. We found that exclusively the PKC dependent disruption was prevented by the selected TLR2-signalling LAB strains. This study suggests that TLR2 is a pivotal epithelial barrier modulator, and provides novel insight in the molecular mechanisms by which LAB contribute to intestinal health.

Fibroblasts Impact Goblet Cell Responses to Lactic Acid Bacteria After Exposure to Inflammatory Cytokines and Mucus Disruptors.

SCOPE: Mucus produced by goblet cells contributes to gut barrier function. Lactic acid bacteria (LAB) have been shown to impact mucus production. It is not completely known whether mucus production is influenced by the abundantly present fibroblasts in the intestine. METHODS AND RESULTS: The influence of fibroblasts on mucus-related genes including mucin-2 (MUC2), trefoil factor 3 (TFF3), resistin-like molecule ß (RETNLB), carbohydrate sulfotransferase 5 (CHST5), and galactose-3-O-sulfotransferase 2 (GAL3ST2) is examined after co-culture of LS174T-goblet cells and CCD-18Co colonic fibroblasts in the presence and absence of LAB-strains known to impact mucus function. This is also tested after exposure to TNF-α, IL-13, or the mucin synthesis inhibitor tunicamycin (Tm). Effects of fibroblasts are treatment duration- and bacterial species-dependent under homeostatic conditions. During TNF-α challenge, fibroblasts reverse Lactobacillus (L.) rhamnosus CCFM237-elicited declined TFF3 expression. After IL-13 exposure, L. rhamnosus CCFM237 and L. fermentum CCFM787 attenuate enhanced TFF3 and RETNLB expression, respectively, only in the presence of fibroblasts. LAB has no effects on Tm-induced decreased expression of goblet cell-related genes regardless of the presence of fibroblasts. CONCLUSION: It is demonstrated that goblet cell-fibroblast crosstalk impacts mucus synthesis and influences the effects of LAB on goblet cell-related genes. Effects are LAB-species and stressor dependent.

Lactic Acid Bacteria May Impact Intestinal Barrier Function by Modulating Goblet Cells.

SCOPE: Lactic acid bacteria (LAB) are recognized to promote gastrointestinal health by mechanisms that are not fully understood. LABs might modulate the mucus and thereby enhance intestinal barrier function. Herein, we investigate effects of different LAB strains and species on goblet cell genes involved in mucus synthesis. METHODS AND RESULTS: Gene expression profiles of goblet-cell-associated products (mucin MUC2, trefoil factor 3, resistin-like molecule ß, carbohydrate sulfotransferase 5, and galactose-3-O-sulfotransferase 2) induced by LAB or their derived conditioned medium in human goblet cell line LS174T are studied. Effects of LAB on gene transcription are assessed with or without exposure to TNF-α, IL-13, or the mucus damaging agent tunicamycin. LAB do impact the related genes in a species- and strain-specific fashion and their effects are different in the presence of the cytokines and tunicamycin. Bioactive factors secreted by some strains are also found to regulate goblet cell-related genes. CONCLUSION: Our findings provide novel insights in differences in modulatory efficacy on mucus genes between LAB species and strains. This study further unravels direct interactions between LAB and intestinal goblet cells, and highlights the importance of rationally selecting appropriate LAB candidates to achieve specific benefits in the gut.

MicroRNA-194 promotes the growth, migration, and invasion of ovarian carcinoma cells by targeting protein tyrosine phosphatase nonreceptor type 12.

Ovarian carcinoma is the most lethal gynecologic malignancy among women. Ovarian cancer metastasis is the main reason for poor prognosis. MicroRNAs (miRNAs) have been shown to play an important role in tumorigenesis and metastasis in various cancers by affecting the expression of their targets. In this study, we explored the role of miR-194 in ovarian cancer. Real-time polymerase chain reaction assays showed that miR-194 was significantly upregulated in ovarian cancer tissues. Overexpression of miR-194 in ovarian cancer cells promotes cell proliferation, migration, and invasion; in contrast, inhibition of the expression of miR-194 has the opposite effects. Meanwhile, bioinformatics tools were used to identify protein tyrosine phosphatase nonreceptor type 12 (PTPN12) as a potential target of miR-194. The luciferase assay showed that miR-194 directly binds to the 3'-untranslated region of PTPN12. Western blot analysis and quantitative real-time polymerase chain reaction assay revealed that PTPN12 expression was negatively associated with miR-194 expression in both ovarian cancer tissues and cells. Thus, we conclude that miR-194 targets PTPN12 and functions as an oncogene in ovarian cancer cells. This novel pathway may provide a new insight to explain ovarian cancer development and metastasis.

Downregulation of BC200 in ovarian cancer contributes to cancer cell proliferation and chemoresistance to carboplatin.

Previous studies have demonstrated that long non-coding RNAs (lncRNAs) serve an important role in carcinogenesis. BC200 is a lncRNA that is reportedly associated with ovarian cancer. The aim of the present study was to investigate this potential association between BC200 and ovarian cancer, and to subsequently analyze the biological function of BC200 in the disease. BC200 expression was compared in ovarian cancer tissue and normal ovarian tissue samples through the use of quantitative polymerase chain reaction. To allow the biological function of BC200 in ovarian cancer to be analyzed, small interfering RNA was used to knock down the expression of BC200 in SKOV3 and A2780 ovarian cancer cells. The proliferative, invasive and migratory abilities of the cells were identified by means of cell counting kits and Transwell assays. Carboplatin was also used to treat the ovarian cancer cells, and a luminescent cell viability assay was subsequently used to detect the sensitivity of the cells to the carboplatin. The results demonstrated that BC200 expression was reduced in ovarian cancer compared with normal ovarian tissue samples. In the SKOV3 and A2780 cells, BC200 exerted no effect on invasive or migratory ability, however, the inhibition of BC200 was demonstrated to promote cell proliferation. Additionally, it was observed that carboplatin induced BC200 expression in the cell lines, and that the inhibition of BC200 decreased the sensitivity of the cells to the drug. BC200 is therefore likely to have a tumor suppressive function in ovarian cancer by affecting cell proliferation. Furthermore, BC200 appears to serve a role in the mediation of carboplatin-induced ovarian cancer cell death.

Epithelial-mesenchymal interconversions and the regulatory function of the ZEB family during the development and progression of ovarian cancer.

This study assessed the role of epithelial-mesenchymal interconversions and the regulatory functions of the ZEB family during the development and progression of ovarian cancer. E-cadherin, vimentin, ZEB1 and ZEB2 were analyzed using immunohistochemistry in a series of ovarian tissues that included normal tissue, benign tumors, borderline tumors, malignant tumors and metastatic lesions. The correlation between E-cadherin and ZEB was analyzed. We also analyzed the association between the expression of the four factors and clinicopathological features in ovarian cancer. The results revealed that E-cadherin was weakly positive in normal ovarian epithelium. Cytoplasmic E-cadherin was significantly increased in benign tumors (P<0.01) and further increased in borderline tumors and ovarian cancers. However, cytoplasmic E-cadherin was markedly reduced in metastatic lesions (P<0.01). Membranous E-cadherin was increased in benign tumors, but decreased progressively in borderline, malignant and metastatic tumor tissues (P<0.05). The expression profile of vimentin was opposite to that of membranous E-cadherin. Membranous E-cadherin was negatively correlated with ZEB2 expression (r=-0.514). Additionally, cytoplasmic E-cadherin, ZEB1 and ZEB2 were associated with the FIGO stage of ovarian cancer. ZEB1 was also correlated with ascitic fluid volume. Our results suggest that epithelial-mesenchymal interconversions are dynamically regulated during the development and progression of ovarian tumors. ZEB2, but not ZEB1, may regulate the expression of membranous E-cadherin during these processes.

Identification of TLR2/TLR6 signalling lactic acid bacteria for supporting immune regulation.

Although many lactic acid bacteria (LAB) influence the consumer's immune status it is not completely understood how this is established. Bacteria-host interactions between bacterial cell-wall components and toll-like receptors (TLRs) have been suggested to play an essential role. Here we investigated the interaction between LABs with reported health effects and TLRs. By using cell-lines expressing single or combination of TLRs, we show that LABs can signal via TLR-dependent and independent pathways. The strains only stimulated and did not inhibit TLRs. We found that several strains such as L. plantarum CCFM634, L. plantarum CCFM734, L. fermentum CCFM381, L. acidophilus CCFM137, and S. thermophilus CCFM218 stimulated TLR2/TLR6. TLR2/TLR6 is essential in immune regulatory processes and of interest for prevention of diseases. Specificity of the TLR2/TLR6 stimulation was confirmed with blocking antibodies. Immunomodulatory properties of LABs were also studied by assessing IL-10 and IL-6 secretion patterns in bacteria-stimulated THP1-derived macrophages, which confirmed species and strain specific effects of the LABs. With this study we provide novel insight in LAB specific host-microbe interactions. Our data demonstrates that interactions between pattern recognition receptors such as TLRs is species and strain specific and underpins the importance of selecting specific strains for promoting specific health effects.

Comprehensive analysis of lncRNA-mRNA co-expression patterns identifies immune-associated lncRNA biomarkers in ovarian cancer malignant progression.

Ovarian cancer (OV) is the most common and lethal gynecological tumor with a poor prognosis for women; however, the regulatory roles of the long non-coding RNAs (lncRNAs) in ovarian malignant progression are insufficiently understood. Here, we investigated the expression patterns of lncRNAs and mRNAs in the high-throughput molecular profiles of 399 OV patients and constructed a functional lncRNA-mRNA co-expression network across OV malignant progression. We found that two protective lncRNAs, RP11-284N8.3.1 and AC104699.1.1, were not only differentially expressed throughout the progression of malignant OV but were also independently predictive of the survival of patients with different OV stages. A functional analysis of the two lncRNAs predicted their roles in immune system activation and other anti-tumor processes in the OV microenvironment. Integrating these two lncRNAs into an OV risk model was able to significantly stratify patients into different risk groups. Overall, our analysis effectively provides insights into the lncRNA association with malignant OV progression. The two-lncRNA signature is a candidate biomarker for the prognosis of patients with OV and may enable a more accurate prediction of survival.

MicroRNA-181a enhances the chemotherapeutic sensitivity of chronic myeloid leukemia to imatinib.

MicroRNA-181 (miR-181) has been recently demonstrated to participate in the differentiation and development of immune cells, including natural killer cells and B and T lymphocytes, and myeloid linages, including erythroid and megakaryocytic cells. The aberrant expression of miR-181, particularly low expression levels, has been observed in a number of leukemia types, including B-cell chronic lymphocytic leukemia and cytogenetically abnormal acute myeloid leukemia. However, the expression and function of miR-181 in chronic myeloid leukemia (CML) remains unknown. In the present study, the aberrant expression of miR-181a was analyzed in a patient with CML and in the CML K562 cell line. In addition, the function and potential mechanisms of miR-181a in K562 cells with regard to their chemotherapeutic sensitivity to imatinib were investigated. The expression levels of miR-181a were significantly reduced in the patient with CML and in the CML K562 cell line. Furthermore, the overexpression of miR-181a in the K562 cells enhanced the chemotherapeutic sensitivity of these cells to imatinib. The potential mechanism mediating these effects may be associated with the capacity of miR-181a to inhibit cell growth and/or to induce cells apoptosis and differentiation in K562 cells. The results of the present study suggested that miR-181a may be a target for the treatment of CML and a useful indicator of the therapeutic sensitivity of CML to imatinib.