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We recently reported that swelling resulting from 2,4,6-trinitrochlorobenzene (TNCB) challenge might be associated with recruitment of neutrophils. However, it is not known whether neutrophil recruitment is affected by scratching at inflamed sites or not. Therefore, the effects of an Elizabethan collar on the TNCB-induced upregulation of ELR-positive chemokines (CXCL1, CXCL2, and CXCL5) and neutrophil recruitment were investigated. Mice were sensitized by the application of TNCB on abdominal skin. Then, the mice were challenged three times with TNCB to auricle of the ear. To prevent scratching at inflamed sites, an Elizabethan collar was placed on the mice from just before the first challenge until the end of the experiment. The effects of the Elizabethan collar on the TNCB-induced upregulation of CXCLs chemokines and recruitment of neutrophil were investigated. The increase of ear swelling by TNCB challenge was inhibited by the Elizabethan collar. TNCB-challenge-induced upregulation of TNF-α, IL-1β, IL-6, ELR+ chemokines, MPO, and ELA2 was also attenuated by the Elizabethan collar. The gene expression of CXCL1, CXCL2, and CXCL5 human homolog IL-8 was enhanced by TNF-α and IL-1β in human dermal fibroblasts and epidermal keratinocytes. We here suggest that scratching the site of inflammation leads to neutrophil accumulation mediated by TNF-α and IL-1β/ELR+ chemokines in TNCB-challenge-induced contact dermatitis in mice. [ABSTRACT FROM AUTHOR]

The compound 5-fluorouracil (5- FU) is used in cancer chemotherapy and is known to cause diarrhoea. We recently reported that chemokine (C-X-C motif) ligand 1 ( CXCL1) and neutrophils in the colonic mucosa were markedly increased by the administration of 5- FU in mice. Curcumin has anti-inflammatory, antitumour and antioxidant properties. Therefore, we examined the effect of curcumin on 5- FU-induced diarrhoea development and CXCL1 and CXCL2 up-regulation in the colon. Mice were given 5- FU (50 mg/kg, i.p.) daily for 4 days. Curcumin (100 or 300 mg/kg, p.o.) was administered on the day before the first administration of 5- FU and administered 30 min. before the administration of 5- FU. Gene expression levels of CXCL1 and CXCL2 in the colon were examined by real-time RT- PCR. Curcumin reduced the 5- FU-induced diarrhoea development. Under this condition, the CXCL1 and CXCL2 gene up-regulated by 5- FU administration was inhibited by curcumin. The gene expression of CXCL1 and CXCL2 was also enhanced by 5- FU application in vitro. The 5- FU-induced up-regulated CXCL1 and CXCL2 gene expressions were inhibited by curcumin, Bay-117082 and bortezomib, nuclear factor kappa B ( NF-κB) inhibitors, C646, a p300/cyclic adenosine monophosphate response element-binding protein-histone acetyltransferase ( HAT) inhibitor. In conclusion, these findings suggested that curcumin prevented the development of diarrhoea by inhibiting NF-κB and HAT activation. [ABSTRACT FROM AUTHOR]

Objective: Trastuzumab has been used for the treatment of HER2-positive breast cancer (BC). However, a subset of BC patients exhibited resistance to trastuzumab therapy. Thus, clarifying the molecular mechanism of trastuzumab treatment will be beneficial to improve the treatment of HER2-positive BC patients. In this study, we identified trastuzumab-responsive microRNAs that are involved in the therapeutic effects of trastuzumab. Methods and Results: RNA samples were obtained from HER2-positive (SKBR3 and BT474) and HER2-negetive (MCF7 and MDA-MB-231) cells with and without trastuzumab treatment for 6 days. Next, we conducted a microRNA profiling analysis using these samples to screen those microRNAs that were up- or down-regulated only in HER2-positive cells. This analysis identified miR-26a and miR-30b as trastuzumab-inducible microRNAs. Transfecting miR-26a and miR-30b induced cell growth suppression in the BC cells by 40% and 32%, respectively. A cell cycle analysis showed that these microRNAs induced G1 arrest in HER2-positive BC cells as trastuzumab did. An Annexin-V assay revealed that miR-26a but not miR-30b induced apoptosis in HER2-positive BC cells. Using the prediction algorithms for microRNA targets, we identified cyclin E2 (CCNE2) as a target gene of miR-30b. A luciferase-based reporter assay demonstrated that miR-30b post-transcriptionally reduced 27% (p = 0.005) of the gene expression by interacting with two binding sites in the 3'-UTR of CCNE2. Conclusion: In BC cells, trastuzumab modulated the expression of a subset of microRNAs, including miR-26a and miR-30b. The upregulation of miR-30b by trastuzumab may play a biological role in trastuzumab-induced cell growth inhibition by targeting CCNE2. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are endogenous non-coding RNAs that function as negative regulators of gene expression. Alterations in miRNA expression have been shown to affect tumor growth and response to chemotherapy. In this study, we explored the possible role of miRNAs in cisplatin resistance in esophageal squamous cell carcinoma (ESCC). First we assessed the sensitivity of nine human ESCC cell lines (KYSE series) to cisplatin using an in vitro cell viability assay, and then we compared the miRNA profiles of the cisplatin-sensitive and -resistant cell lines by miRNA microarray analysis. The two groups showed markedly different miRNA expression profiles, and 10 miRNAs were found to be regulated differentially between the two groups. When miR-141, which was the most highly expressed miRNA in the cisplatin-resistant cell lines, was expressed ectopically in the cisplatin-sensitive cell lines, cell viability after cisplatin treatment was increased significantly. Furthermore, we found that miR-141 directly targeted the 3′-untranslated region of YAP1, which is known to have a crucial role in apoptosis induced by DNA-damaging agents, and thus downregulated YAP1 expression. Our study highlights an important regulatory role for miR-141 in the development of cisplatin resistance in ESCC. [ABSTRACT FROM AUTHOR]

Abstract: Mutations in PTEN-induced putative kinase 1 (PINK1) cause recessive form of Parkinson’s disease (PD). PINK1 acts upstream of parkin, regulating mitochondrial integrity and functions. Here, we show that PINK1 in combination with parkin results in the perinuclear mitochondrial aggregation followed by their elimination. This elimination is reduced in cells expressing PINK1 mutants with wild-type parkin. Although wild-type PINK1 localizes in aggregated mitochondria, PINK1 mutants localization remains diffuse and mitochondrial elimination is not observed. This phenomenon is not observed in autophagy-deficient cells. These results suggest that mitophagy controlled by the PINK1/parkin pathway might be associated with PD pathogenesis. Structured summary: MINT-7557195: PINK1 (uniprotkb:Q9BXM7) physically interacts (MI:0915) with LC3 (uniprotkb:Q9GZQ8) by anti tag coimmunoprecipitation (MI:0007) MINT-7557109: LC3 (uniprotkb:Q9GZQ8) and PINK1 (uniprotkb:Q9BXM7) colocalize (MI:0403) by fluorescence microscopy (MI:0416) MINT-7557121: tom20 (uniprotkb:Q15388) and PINK1 (uniprotkb:Q9BXM7) colocalize (MI:0403) by fluorescence microscopy (MI:0416) MINT-7557138: parkin (uniprotkb:O60260), PINK1 (uniprotkb:Q9BXM7) and tom20 (uniprotkb:Q15388) colocalize (MI:0403) by fluorescence microscopy (MI:0416) MINT-7557173: LC3 (uniprotkb:Q9GZQ8) physically interacts (MI:0915) with PINK1 (uniprotkb:Q9BXM7) by anti bait coimmunoprecipitation (MI:0006) [Copyright &y& Elsevier]

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by inhibiting translation and/or inducing degradation of target mRNAs, and they play important roles in a wide variety of biological functions including cell differentiation, tumorigenesis, apoptosis and metabolism. However, there is a paucity of information concerning the regulatory mechanism of miRNA expression. Here we report identification of growth factor-regulated miRNAs using the PC12 cell line, an established model of neuronal growth and differentiation. We found that expression of miR-221 and miR-222 expression were induced by nerve growth factor (NGF) stimulation in PC12 cells, and that this induction was dependent on sustained activation of the extracellular signal-regulated kinase 1 and 2 (ERK1/2) pathway. Using a target prediction program, we also identified a pro-apototic factor, the BH3-only protein Bim, as a potential target of miR-221/222. Overexpression of miR-221 or miR-222 suppressed the activity of a luciferase reporter activity fused to the 3′ UTR of Bim mRNA. Furthermore, overexpression of miR-221/222 decreased endogenous Bim mRNA expression. These results reveal that the ERK signal regulates miR-221/222 expression, and that these miRNAs might contribute to NGF-dependent cell survival in PC12 cells. [ABSTRACT FROM AUTHOR]

Over the last decade, DNA microarray technology has provided a great contribution to the life sciences. The MicroArray Quality Control (MAQC) project demonstrated the way to analyze the expression microarray. Recently, microarray technology has been utilized to analyze a comprehensive microRNA expression profiling. Currently, several platforms of microRNA microarray chips are commercially available. Thus, we compared repeatability and comparability of five different microRNA microarray platforms (Agilent, Ambion, Exiqon, Invitrogen and Toray) using 309 microRNAs probes, and the Taqman microRNA system using 142 microRNA probes. This study demonstrated that microRNA microarray has high intraplatform repeatability and comparability to quantitative RT-PCR of microRNA. Among the five platforms, Agilent and Toray array showed relatively better performances than the others. However, the current lineup of commercially available microRNA microarray systems fails to show good inter-platform concordance, probably because of lack of an adequate normalization method and severe divergence in stringency of detection call criteria between different platforms. This study provided the basic information about the performance and the problems specific to the current microRNA microarray systems. [ABSTRACT FROM AUTHOR]

Objectives: Gene expression profiling using pretreatment biopsies has been limited due to their small sample sizes. This study evaluated the usefulness of an ultrasensitive new DNA microarray chip, which has a unique array structure, for the clinical diagnosis of esophageal cancer using preoperative biopsies. Methods: Paired cancer and normal esophageal epithelial tissues from 56 patients who underwent esophagectomy and from 48 patients who underwent preoperative endoscopy were studied. Among 2 feature gene sets selected by a reference DNA chip discriminating malignant status of samples, 20 feature genes were selected for the development of the new DNA chip. The new DNA chip was hybridized with 0.1 μg of total RNA per slide without RNA amplification. Results: Twenty feature genes, including RRM-2 and XRCC-3, for the new DNA chip could discriminate cancer from noncancer at a 95.2% rate of accuracy in 42 biopsies (sensitivity 95.7%, specificity 94.7%). A receiver operating characteristic (ROC) curve analysis showed that the area under ROC curve for the prediction was 0.966. Conclusions: The gene expression profiles from the preoperative biopsies could diagnose esophageal cancer accurately, using the ultrasensitive DNA chip without RNA amplification. This new DNA chip technology might contribute further to the development of customized therapeutic strategies for various cancer patients. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel method for sparse logistic regression with non-convex regularization Lp (p <1). Based on smooth approximation, we develop several fast algorithms for learning the classifier that is applicable to high dimensional dataset such as gene expression. To the best of our knowledge, these are the first algorithms to perform sparse logistic regression with an Lp and elastic net (Le) penalty. The regularization parameters are decided through maximizing the area under the ROC curve (AUC) of the test data. Experimental results on methylation and microarray data attest the accuracy, sparsity, and efficiency of the proposed algorithms. Biomarkers identified with our methods are compared with that in the literature. Our computational results show that Lp Logistic regression (p <1) outperforms the L1 logistic regression and SCAD SVM. Software is available upon request from the first author. [ABSTRACT FROM AUTHOR]

Background: Adipogenesis, the process of preadipocyte differentiation to mature adipocytes accompanied by accumulation of intracytoplasmic lipid droplets, is regulated by various genetic and environmental factors, and closely associated with the development of obesity. Numerous recent studies suggest that some bioactive peptides and proteins derived from animals, and chemical compounds isolated from plants may be useful for prevention and treatment of obesity and obesity-related chronic diseases. In the present study, we examined the broad spectrum of effects of placental extract, with a focus on the influence of placental extract on adipogenesis. Method: We cultured 3T3-L1 cells, which are widely used as a model of white preadipocytes, under differentiation conditions in the presence of porcine placental extract (PPE) for 8 days, and then stained the lipid droplets accumulated in the cytoplasm with Oil Red O. We also analyzed the effects of PPE on the mitogen-activated protein kinases (MAPKs) signaling, mitotic clonal expansion (MCE) and gene expressions associated with 3T3-L1 differentiation. Results: When we cultured 3T3-L1 cells with PPE under differentiation conditions, the accumulation of lipid droplets and expression of adipocyte differentiation marker genes (Cebpa, Pparg, Slc2a4, Fasn and Adipoq) were dramatically attenuated. The suppressive activity of PPE against adipogenesis was heat-stable and recovered in a low-molecular-weight fraction after ultrafiltration (< 3 kDa) and gel-filtration chromatography (fraction No. 9). We also found that the suppressive activity of PPE affected the early phase of adipocyte differentiation (Days 0–2) without influencing the expression levels of C/EBPβ and C/EBPδ. The PPE and fraction No. 9 obtained from gel-filtration chromatography both promoted mitotic clonal expansion of 3T3-L1 while accelerating p38 MAPK phosphorylation. In addition, SB203580, a p38 MAPK inhibitor, partially restored the accumulation of lipid droplets and the expression of adipocyte differentiation marker genes that were suppressed by fraction No. 9. Conclusion: These results indicate that PPE suppresses the differentiation of preadipocytes via accelerated activation of p38 MAPK during the early phase of adipogenesis, suggesting PPE or its functional component could be a potential therapy for treating obesity. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with a high probability of metastasis and a lack of specific targets and targeted therapeutics. Previously, we have reported that COL8A1, which is highly expressed in the mesenchymal stem-like (MSL) subtype of TNBC, facilitates TNBC growth via FAK/Src activation. Furthermore, we have found that COL8A1 enhances the invasion and metastasis of MDA-MB-231 cells, classified into MSL. However, the mechanism of invasion and metastasis by COL8A1 remains unclear. Here, we investigated the biological function of COL8A1 on the invasion and metastasis of MDA-MB-231 cells. The invasion and metastasis of MDA-MB-231 cells were evaluated using three-dimensional (3D) culture methods and xenograft mouse models. DNA microarray analysis examined the gene expression in COL8A1-overexpressing MDA-MB-231 cells and control cells. Gene expression was verified using RT-qPCR. COL8A1-deficient cells showed little or no metastasis, whereas forced expression of COL8A1 in MDA-MB-231 cells, the MSL subtype of TNBC cell lines, significantly promoted distant metastasis after tumor resection. As with in vivo , 3D invasion assay revealed that COL8A1 increased the invasion capacity of MDA-MB-231 and Hs578T cells, classified into the MSL subtype of TNBC. DNA microarray analysis for COL8A1-overexpressing cells indicated that COL8A1 induces interleukin 1B (IL1B) and matrix metalloproteinase-1 (MMP1) expression, both of which are correlated with COL8A1 expression in the mesenchymal subtypes of TNBC, and the Kaplan–Meier plotter provided evidence that the prognosis in the MSL subtype was strongly associated with both gene expressions and COL8A1 expression. Pharmacological inhibitor treatment showed that COL8A1 regulated IL1B and MMP1 expression through a different pathway. Moreover, the knockdown of each gene expression reduced the invasion capacity of COL8A1-overexpressing MDA-MB-231 and Hs578T cells. Our findings indicate that COL8A1-induced IL1B and MMP1 enhanced the invasion and metastasis of the MSL subtype of TNBC. Considering our previous findings that COL8A1 promotes tumor growth, COL8A1 may be a prognostic and practical therapeutic target in TNBC. [Display omitted] • COL8A1 enhances the invasion and metastasis of MDA-MB-231 cells, classified into MSL. • COL8A1 induces IL1B and MMP1 expression in MDA-MB-231 cells. • Poor prognosis in the MSL subtype was strongly associated with IL1B and MMP1.. • COL8A1 regulated IL1B and MMP1 expression through a different pathway. • Knockdown experiment revealed COL8A1-induced IL1B and MMP1 increased the invasion. [ABSTRACT FROM AUTHOR]

[Display omitted] Patients with cancer often experience muscle atrophy, which worsens their prognosis. Decreased muscle regenerative capacity plays an important role in the complex processes involved in muscle atrophy. Administration of cisplatin, a cancer chemotherapeutic agent, has been implicated as a cause of muscle atrophy. In this study, we examined whether cisplatin affects the differentiation of myoblasts into myotubes. We treated C2C12 myoblasts with a differentiation medium containing cisplatin and its vehicle during for 8 days and observed the changes in the expression of myosin heavy chain (MyHC) and myogenin in the myoblasts. Cisplatin was injected in mice for 4 consecutive days; on Day 5, the mice quadriceps muscles were sampled and examined. The expression of MyHCs increased and that of myogenin decreased after cisplatin treatment. The secretion of acidic cysteine-rich proteins (e.g., Sparc proteins) reportedly promotes C2C12 myoblast differentiation. Therefore, we investigated the Sparc family gene expression during myogenesis in C2C12 myoblasts after cisplatin treatment. Of all the genes investigated, Sparc-like protein 1 (Sparcl1) expression was significantly suppressed by cisplatin on Days 4–8. Simultaneous treatment with recombinant mouse Sparcl1 almost inhibited the cisplatin-induced suppression of total MyHC and myogenin protein levels. Moreover, Sparcl1 expression decreased in the skeletal muscles of mice, leading to cisplatin-induced muscle atrophy. Our results suggest that cisplatin-induced myogenesis suppression causes muscle atrophy and inhibits the expression of Sparcl1 , which promotes C2C12 cell differentiation during myogenesis. [ABSTRACT FROM AUTHOR]