Project description:NADPH oxidases (NOXs) are a family of transmembrane proteins that generates reactive oxygen species. We previously reported that patients with colon cancer who had high NOX5 expression had poor prognosis. However, no studies have studied the cellular functions of NOX5 in colon cancer. This study aimed to clarify the relationship between NOX5 and cancer development using an in vitro model. Real-time quantitative PCR was performed to determine the NOX5 expressions levels of colon cancer cell lines. NOX5 knockdown experiments were conducted, and the impact on cell proliferation, migration, and invasion were analyzed. In addition, mRNA microarray was conducted to assess changes in gene profile. NOX5 mRNA expression was high in HCT116 cells and moderate in SW48 cells. NOX5 knockdown significantly inhibited cell migration and invasion in both HCT116 and SW48 cells; however, NOX5 knockdown reduced cell proliferation in only HCT116 cells. mRNA microarrays showed a strong relationship between NOX5 expression levels and integrin-linked kinase signaling pathways. The NOX5 expression in colon cancer cells affects cancer progression, especially cell motility. NOX5 may be a novel therapeutic target for the future development of treatments for colon cancer.
Project description:Mycobacterium tuberculosis’success as a pathogen comes from itsability to evade degradation by macrophages. Normally macro-phages clear microorganisms that activate pathogen-recognitionreceptors (PRRs) through a lysosomal-trafficking pathway called“LC3-associated phagocytosis”(LAP). AlthoughM.tuberculosisac-tivates numerous PRRs, for reasons that are poorly understoodLAP does not substantially contribute toM.tuberculosiscontrol.LAP depends upon reactive oxygen species (ROS) generated byNADPH oxidase, butM.tuberculosisfails to generate a robustoxidative response. Here, we show that CpsA, a LytR-CpsA-Psr(LCP) domain-containing protein, is required forM.tuberculosisto evade killing by NADPH oxidase and LAP. Unlike phagosomescontaining wild-type bacilli, phagosomes containing theΔcpsAmutant recruited NADPH oxidase, produced ROS, associated withLC3, and matured into antibacterial lysosomes. Moreover, CpsAwas sufficient to impair NADPH oxidase recruitment to fungal par-ticles that are normally cleared by LAP. Intracellular survival of theΔcpsAmutant was largely restored in macrophages missing LAPcomponents (Nox2,Rubicon,Beclin,Atg5,Atg7,orAtg16L1) butnot in macrophages defective in a related, canonical autophagypathway (Atg14,Ulk1,orcGAS). TheΔcpsAmutant was highlyimpaired in vivo, and its growth was partially restored in micedeficient in NADPH oxidase,Atg5,orAtg7, demonstrating thatCpsA makes a significant contribution to the resistance ofM.tu-berculosisto NADPH oxidase and LC3 trafficking in vivo. Overall,our findings reveal an essential role of CpsA in innate immuneevasion and suggest that LCP proteins have functions beyond theirpreviously known role in cell-wall metabolism.
Project description:NADPH dependent phagocytic oxidase, by producing hydroxyradicals such as hydrogen peroxide, is essential for host defense against Salmonella infection. We used gene array analysis to identify Salmonella enterica serovar Typhimurium genes regulated by NADPH dependent phagocytic oxidase intracellularly in comparison to those expressed in vitro by hydrogen peroxide.
Project description:Small nucleolar RNAs (snoRNAs) guide nucleotide modifications of cellular RNAs in the nucleus. We have previously shown that box C/D snoRNAs from the Rpl13a locus are unexpected mediators of physiologic oxidative stress, independent of their predicted ribosomal RNA modifications. Here, we demonstrate that oxidative stress induced by doxorubicin causes rapid cytoplasmic accumulation of the Rpl13a snoRNAs through a mechanism that requires superoxide and a nuclear splice variant of NADPH oxidase. RNA-sequencing analysis reveals that box C/D snoRNAs as a class are present in the cytoplasm, where their levels are dynamically regulated by NADPH oxidase. These findings suggest that snoRNAs may orchestrate the response to environmental stress through molecular interactions outside of the nucleus.
Project description:Plasma membrane NADPH oxidases (NOXs) are major producers of reactive oxygen species (ROS) in plant cells under normal growth and stress conditions. Rice NOXs have multiple homologs but their functional mechanisms are largely unknown. We used microarrays to detail the global gene expression profiles in rice wild-type (WT, Dongjin) and a mutant osnox2 which loss the functions of OsNOX2 protein under drought and identified distinct classes of genes between the two type rice plants under both normal growth and drought stressed conditions.
Project description:Genetic defects in neutrophil function or trafficking are highly associated with oral inflammation and periodontitis. The leukocyte NADPH oxidase enzymes complex is a multi-subunit enzyme that has been described to play important immunomodulatory roles in limiting the inflammatory responses of neutrophils and macrophages. Here, we determined the impact of loss of NADPH oxidase dependent reactive oxygen species (ROS) generation in gingival inflammatory responses using a model of ligature induced murine periodontitis.
Project description:Daunorubicin (DNR) and Cytarabin (Ara-C) are the main chemotherapeutic drugs used for Acute Myeloid Leukemias (AML) treatment. However, their mode of action is not well understood. To decipher if these drug would induce rapid transcriptional reprogramming, we treated HL-60 AML cell line with DNR or Ara-C for 3 hours and carried out a transcriptomic analyses. In addition, we had shown that Reactive Oxigen Species (ROS) produced by NADPH oxidases (NOX) are involved in DNR-induced gene expression. We therefore also performed a transcriptomic analyses in HL-60 cells treated with DNR and VAS2870, an NADPH oxidase inhibitor. HL-60 cells were treated or not for 3 hours with 2 µM Ara-C, 1 µM DNR or 1 µM DNR + 20µM VAS 2870. RNAs were purified from 3 independent experiments and used to probe Affymetrix Human Gene 2.0 ST Genechips