BackgroundMicroRNAs are non-coding RNA molecules that posttranscriptionally regulate expression of target genes and have been implicated in the progress of cancer proliferation, differentiation and apoptosis. The aim of this study was to determine whether microRNA-21 (miR-21), a specific microRNA implicated in multiple aspects of carcinogenesis, impacts breast cancer invasion by regulating the tissue inhibitor of metalloproteinase 3 (TIMP3) gene.MethodsmiR-21 expression was investigated in 32 matched breast cancer and normal breast tissues, and in four human breast cancer cell lines, by Taqman quantitative real-time PCR. Cell invasive ability was determined by matrigel invasion assay in vitro, in cells transfected with miR-21 or anti-miR-21 oligonucleotides. In addition, the regulation of tissue inhibitor of metalloproteinase 3 (TIMP3) by miR-21 was evaluated by western blotting and luciferase assays.ResultsOf the 32 paired samples analyzed, 25 breast cancer tissues displayed overexpression of miR-21 in comparison with matched normal breast epithelium. Additionally, incidence of lymph node metastasis closely correlated with miR-21 expression, suggesting a role for miR-21 in metastasis. Similarly, each of the four breast cancer cell lines analyzed overexpressed miR-21, to varied levels. Further, cells transfected with miR-21 showed significantly increased matrigel invasion compared with control cells, whereas transfection with anti-miR-21 significantly decreased cell invasion. Evaluation of TIMP3 protein levels, a peptidase involved in extarcellular matrix degredation, inversely correlated with miR-21 expression.ConclusionAs knockdown of miR-21 increased TIMP3 protein expression and luciferase reporter activity, our data suggests that miR-21 could promote invasion in breast cancer cells via its regulation of TIMP3.

Inflammation occurs throughout the progression of cerebral ischemia/reperfusion and mediates myriads of pathological events following an ischemic insult.

Background Information about the about the prevalence and correlates of self-reported medication nonadherence using multiple measures in older adults with chronic cardiovascular conditions is needed. Objective To examine the prevalence and correlates of self-reported medication nonadherence among community-dwelling elders with chronic cardiovascular conditions. Methods Participants (n=897) included members from the Health, Aging and Body Composition study with coronary heart disease, diabetes mellitus, and/or hypertension at year 10. Self-reported nonadherence was measured by the 4-item Morisky Medication Adherence Scale (MMAS-4) and 2-item cost-related nonadherence (CRN-2) scale at year 11. Factors (demographic, health status, and access to care) were examined for association with the MMAS-4 and then for association with the CRN-2 scale. Results Nonadherence per the MMAS-4 and CRN-2 scale was reported by 40.7% and 7.7% of participants, respectively, with little overlap (3.7%). Multivariable logistic regression analyses found that black race was significantly associated with nonadherence per the MMAS-4 (p=0.002) and the CRN-2 scale (p=0.005). Other correlates of nonadherence per the MMAS-4 (with independent associations) included having cancer (p=0.04), a history of falls (p=0.02), sleep disturbances (p=0.04) and having a hospitalization in the previous 6 months (p=0.005). Conversely, being unmarried (p=0.049), having worse self-reported health (p=0.04) and needs being poorly met by income (p=0.02) showed significant independent associations with nonadherence per the CRN-2 scale. Conclusions Self-reported medication nonadherence was common in older adults with chronic cardiovascular conditions and only one factor – race – was associated with both types. The research implication of this finding is that it highlights the need to measure both types of self-reported nonadherence in older adults. Moreover, the administration of these quick measures in the clinical setting should help identify specific actions such as patient education or greater use of generic medications or pill boxes that may address barriers to medication nonadherence.

We newly genotyped 6,483 cases and 5,488 controls using the Illumina Global Screening Array (GSA), which included two studies (East-GWAS: 4,872 cases and 3,397 controls from Jiangsu province and Shanghai; North-GWAS: 1,611 cases and 2,091 controls from Shandong province, Hebei province and Tianjin). We consecutively recruited histopathologically confirmed gastric cancer cases from hospitals. Cancer-free controls were selected from individuals receiving routine physical examination at hospitals or those participating in community screening for non-communicable diseases. Demographic characteristics of all participants were displayed in Table S1. Onco-GWAS:Histopathologically confirmed gastric cancer cases were consecutively recruited from hospitals in Jiangsu province, China. The cancer-free control subjects were selected from individuals receiving routine physical examination at hospitals or those participating in community screening for non-communicable diseases in Jiangsu province. A total of 1,140 cases and 345 controls were genotyped using the Illumina OncoArray, and 708 controls were genotyped using the Illumina OmniZhongHua chips (Table S1). Detailed study design and genotype calling was provided previously. 1 NJ-GWAS and BJ-GWAS:For the NJ-GWAS and BJ-GWAS, individuals were derived from separate casecontrol studies conducted in Nanjing (565 cases and 1,162 controls) and Beijing (468 cases and 1,123 controls) (Table S1). Individuals were genotyped using the Affymetrix Genome-Wide Human SNP Array (V.6.0), which consisting ~ 900,000 markers. The details of study design and relevant data were reported previously. 2 1.4 SX-GWAS: A total of 1625 gastric cancer cases and 2100 controls were from the Shanxi Upper Gastrointestinal Cancer Genetics Project and the Linxian Nutrition Intervention Trial (Table S1). All participants were genotyped using the Illumina 660W Quad chip. The study was reported elsewhere 3 and the genotype data was downloaded from dbGap (study accession: phs00361.v1.p1). Quality control.The same protocol of quality control procedures on genotyping data was applied for all six GWAS datasets. The genotyped variants were excluded if they had a call rate of <95%, a P value for Hardy-Weinberg Equilibrium (HWE) in controls ≤1.0×10 −6 or a minor allele frequency (MAF) of <1% in controls; and samples were removed if they were with call rates of <95%, outliers (>6 s.d. from the mean) in population stratification analysis and heterozygosity analysis, or duplicated or related individuals (PI_HAT > 0.25).A total of 100,641 samples in the CKB cohort were genotyped with a customized Affymetrix Axiom® CKB array. Samples with call rate < 98% or gender discrepancy, or samples with extreme heterozygosity (F statistic S.D. score <5) were excluded. Variants with call rate <95% were excluded. Variants with call rate ≥ 95% and < 98%, or deviation from the expected frequency as observed in the 1000 Genomes project (the Phase III integrated variant set release, 504 East Asians), or deviation from Hardy-Weinberg disequil...

A wide variety of enveloped viruses infects cells by taking advantage of the low pH in the endocytic pathway to trigger virus-membrane fusion. For alphaviruses such as Semliki Forest virus (SFV), acidic pH initiates a series of conformational changes in the heterodimeric virus envelope proteins E1 and E2. Low pH dissociates the E2/E1 dimer, releasing the membrane fusion protein E1. E1 inserts into the target membrane and refolds to a trimeric hairpin conformation, thus driving the fusion reaction. The means by which E1 senses and responds to low pH is unclear, and protonation of conserved E1 histidine residues has been proposed as a possible mechanism. We tested the role of four conserved histidines by mutagenesis of the wild-type (wt) SFV infectious clone to create virus mutants with E1 H3A, H125A, H331A, and H331A/H333A mutations. The H125A, H331A, and H331A/H333A mutants had growth properties similar to those of wt SFV and showed modest change or no change in the pH dependence of virus-membrane fusion. By contrast, the E1 H3A mutation produced impaired virus growth and a markedly more acidic pH requirement for virus-membrane fusion. The dissociation of the H3A heterodimer and the membrane insertion of the mutant E1 protein were comparable to those of the wt in efficiency and pH dependence. However, the formation of the H3A homotrimer required a much lower pH and showed reduced efficiency. Together, these results and the location of H3 suggest that this residue acts to regulate the low-pH-dependent refolding of E1 during membrane fusion.Enveloped viruses infect cells by fusing their membrane with that of the target cell through the action of transmembrane proteins in the virus envelope (15, 47). These membrane fusion proteins, although differing in structure among different enveloped viruses, nonetheless act through a common mechanism. Following an initial triggering event, the fusion protein interacts with the target membrane via a hydrophobic fusion peptide(s) and refolds into a hairpin-like conformation with the transmembrane domain and fusion peptide at the same end of the molecule. To date, the postfusion structures of all virus fusion proteins are trimeric hairpins. The triggering events for virus membrane fusion include virus-receptor/coreceptor interactions, exposure to a mildly acidic pH, and a combination of these processes. The critical triggering events can occur at the plasma membrane or within the low-pH environment of the endocytic pathway. While there has been remarkable progress in our understanding of the structures of virus membrane fusion proteins, the mechanism of triggering and the process of conversion from the prefusion conformation to the postfusion conformation are not understood.Semliki Forest virus (SFV) is a member of the alphaviruses, a genus of small, enveloped, plus-strand RNA viruses (25). SFV infects cells through a low-pH-triggered fusion reaction mediated by the E1 transmembrane protein (19). E1 is an elongated molecule containing three domains (DI, DII, and DIII) composed p...

Zeaxanthin (Zea) is a major carotenoid pigment contained in human retina, and its daily supplementation associated with lower risk of age-related macular degeneration. Despite known property of Zea as an antioxidant, its underlying molecular mechanisms of action remain poorly understood. In this study, we aim to study the regulation mechanism of Zea on phase II detoxification enzymes. In normal human retinal pigment epithelium cells, Zea promoted the nuclear translocation of NF-E2-related factor 2 (Nrf2) and induced mRNA and protein expression of phase II enzymes, the induction was suppressed by specific knockdown of Nrf2. Zea also effectively protected against tert-butyl hydroperoxide-induced mitochondrial dysfunction and apoptosis. Glutathione (GSH) as the most important antioxidant was also induced by Zea through Nrf2 activation in a time- and dose-dependent manner, whereas the protective effects of Zea were decimated by inhibition of GSH synthesis. Finally, Zea activated the PI3K/Akt and MAPK/ERK pathway, whereas only PI3K/Akt activation correlated with phase II enzymes induction and Zea protection. In further in vivo analyses, Zea showed effects of inducing phase II enzymes and increased GSH content, which contributed to the reduced lipid and protein peroxidation in the retina as well as the liver, heart, and serum of the Sprague–Dawley rats. For the first time, Zea is presented as a phase II enzymes inducer instead of being an antioxidant. By activating Nrf2-mediated phase II enzymes, Zea could enhance anti-oxidative capacity and prevent cell death both in vivo and in vitro.

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Overexpression or activation of AKT is very well known to control cell growth, survival, and gene expression in solid tumors. Oridonin, an inflammatory medical and diterpenoid compound isolated from , has exhibited various pharmacologic and physiologic properties, including antitumor, antibacterial, and anti-inflammatory effects. In this study, we demonstrated that oridonin is an inhibitor of AKT and suppresses proliferation of esophageal squamous cell carcinoma (ESCC) and The role of AKT in ESCC was studied using immuno-histochemical analysis of a tumor microarray, the effect of AKT knockdown on cell growth, and treatment of cells with MK-2206, an AKT inhibitor. Oridonin blocked AKT kinase activity and interacted with the ATP-binding pocket of AKT. It inhibited growth of KYSE70, KYSE410, and KYSE450 esophageal cancer cells in a time- and concentration-dependent manner. Oridonin induced arrest of cells in the G-M cell-cycle phase, stimulated apoptosis, and increased expression of apoptotic biomarkers, including cleaved PARP, caspase-3, caspase-7, and Bim in ESCC cell lines. Mechanistically, we found that oridonin diminished the phosphorylation and activation of AKT signaling. Furthermore, a combination of oridonin and 5-fluorouracil or cisplatin (clinical chemotherapeutic agents) enhanced the inhibition of ESCC cell growth. The effects of oridonin were verified in patient-derived xenograft tumors expressing high levels of AKT. In summary, our results indicate that oridonin acts as an AKT inhibitor to suppress the growth of ESCC by attenuating AKT signaling. .