Fibroblast growth factor 2 restrains ras-driven proliferation of malignant cells by triggering RhoA-mediated senescence

Fibroblast growth factor 2 (FGF2) is considered to be a bona fide oncogenic factor, although results from our group and others call this into question. Here, we report that exogenous recombinant FGF2 irreversibly inhibits proliferation by inducing senescence in Ras-dependent malignant mouse cells, but not in immortalized nontumorigenic cell lines. We report the following findings in K-Ras-dependent malignant YI adrenocortical cells and H-Ras V12-transformed BALB-3T3 fibroblasts: (a) FGF2 inhibits clonal growth and tumor onset in nude and immunocompetent BALB/c mice, (b) FGF2 irreversibly blocks the cell cycle, and (c) FGF2 induces the senescence-associated -galactosidase with no accompanying signs of apoptosis or necrosis. The tyrosine kinase inhibitor PD173074 completely protected malignant cells from FGF2. In Yl adrenal cells, reducing the constitutively high levels of K-Ras-GTP using the dominant-negative RasN17 mutant made cells resistant to FGF2 cytotoxicity. In addition, transfection of the dominant-negative RhoA-N19 into either YI or 3T3-B61 malignant cell lines yielded stable clonal transfectants that were unable to activate RhoA and were resistant to the FGF2 stress response. We conclude that in Rasdependent malignant cells, FGF2 interacts with its cognate receptors to trigger a senescence-like process involving RboAGTP. Surprisingly, attempts to select FGF2-resistant cells from the Yl and 3T3-B61 cell lines yielded only rare clones that (a) had lost the overexpressed ras oncogene, (b) were dependent on FGF2 for proliferation, and (c) were poorly tumorigenic. Thus, FGF2 exerted a strong negative selection that Rasdependent malignant cells could rarely overcome.

Arginine vasopressin controls p27(KiP1) protein expression by PKC activation and irreversibly inhibits the proliferation of K-Ras-dependent mouse Y1 adrenocortical malignant cells

The neurohypophyseal hormone arginine vasopressin (AVP) is a classic mitogen in many cells. In K-Ras-dependent mouse Y1 adrenocortical malignant cells, AVP elicits antagonistic responses such as the activation of the PKC and the ERK1/2 mitogenic pathways to down-regulate cyclin D1 gene expression, which induces senescence-associated beta-galactosidase (SA-beta Gal) and leads to cell cycle arrest. Here, we report that in the metabolic background of Y1 cells, PKC activation either by AVP or by PMA inhibits the PI3K/Akt pathway and stabilises the p27(Kip1) protein even in the presence of the mitogen fibroblast growth factor 2 (FGF2). These results suggest that p27(Kip1) is a critical signalling node in the mechanisms underlying the survival of the Y1 cells. In Y1 cells that transiently express wild-type p27(Kip1), AVP caused a severe reduction in cell survival, as shown by clonogenic assays. However, AVP promoted the survival of Y1 cells transiently expressing mutant p27-S10A or mutant p27-T187A, which cannot be phosphorylated at Ser10 and Thr187, respectively. In addition, PKC activation by PMA mimics the toxic effect caused by AVP in Y1 cells, and inhibition of PKC completely abolishes the effects caused by both PMA and AVP in clonogenic assays. The vulnerability of Y1 cells during PKC activation is a phenotype conditioned upon K-ras oncogene amplification because K-Ras down-regulation with an inducible form of the dominant-negative mutant H-RasN17 has resulted in Y1 cells that are resistant to AVP`s deleterious effects. These data show that the survival destabilisation of K-Ras-dependent Y1 malignant cells by AVP requires large quantities of the p27(Kip1) protein as well as phosphorylation of the p27(Kip1) protein at both Ser10 and Thr187. (C) 2011 Elsevier B.V. All rights reserved.

Overexpression of Nrp/b (nuclear restrict protein in brain) suppresses the malignant phenotype in the C6/ST1 glioma cell line

Upon searching for glucocorticoid-regulated cDNA sequences associated with the transformed to normal phenotypic reversion of C6/ST1 rat glioma cells, we identified Nrp/b (nuclear restrict protein in brain) as a novel rat gene. Here we report on the identification and functional characterization of the complete sequence encoding the rat NRP/B protein. The cloned cDNA presented a 1767 nucleotides open-reading frame encoding a 589 aminoacids residues sequence containing a BTB/POZ (broad complex Tramtrack bric-a-brac/Pox virus and zinc finger) domain in its N-terminal region and kelch motifs in its C-terminal region. Sequence analysis indicates that the rat Nrp/b displays a high level of identity with the equivalent gene orthologs from other organisms. Among rat tissues, Nrp/b expression is more pronounced in brain tissue. We show that overexpression of the Nrp/b cDNA in C6/ST1 cells suppresses anchorage independence in vitro and tumorigenicity in vivo, altering their malignant nature towards a more benign phenotype. Therefore, Nrp/b may be postulated as a novel tumor suppressorgene, with possible relevance for glioblastoma therapy. (C) 2009 Elsevier Ltd. All rights reserved.

Sdo1p, the yeast orthologue of Shwachman-Bodian-Diamond syndrome protein, binds RNA and interacts with nuclear rRNA-processing factors

The Shwachman-Bodian-Diamond syndrome protein (SBDS) is a member of a highly conserved protein family of not well understood function, with putative orthologues found in different organisms ranging from Archaea, yeast and plants to vertebrate animals. The yeast orthologue of SBDS, Sdo1p, has been previously identified in association with the 60S ribosomal subunit and is proposed to participate in ribosomal recycling. Here we show that Sdo1p interacts with nucleolar rRNA processing factors and ribosomal proteins, indicating that it might bind the pre-60S complex and remain associated with it during processing and transport to the cytoplasm. Corroborating the protein interaction data, Sdo1p localizes to the nucleus and cytoplasm and co-immunoprecipitates precursors of 60S and 40S subunits, as well as the mature rRNAs. Sdo1p binds RNA directly, suggesting that it may associate with the ribosomal subunits also through RNA interaction. Copyright (C) 2009 John Wiley & Sons, Ltd.

Restless legs syndrome - en beskrivning av dess inverkan på individens sömn, livskvalitet samt olika behandlingsformer : En systematisk litteraturstudie

Syftet med denna systematiska litteraturstudie var att beskriva hur restless legs inverkar på individens sömn och livskvalitet. Syftet var även att granska vilka olika former av behandlingar som finns att tillgå vid restless legs. För att finna information om detta ämne har endast vetenskapliga artiklar använts. Datainsamlingen har skett via databaser, internet samt Högskolans bibliotek, och artiklar från år 1995 och framåt har valts ut. Inklusionskriterier för denna studie var att de valda artiklarna skulle vara internationella vetenskapliga artiklar i fulltext. De funna artiklarna granskades med avseende på vetenskaplig kvalitet och poängsattes utifrån för ändamålet avsedda granskningsmallar. Denna bedömning resulterade i 21 artiklar. Resultatet visade att restless legs patienter upplever sömnbristen som det största problemet. För flertalet individer som drabbas av restless legs försämrades livskvaliteten och patienterna drabbades vanligtvis av psykologiska och fysiologiska besvär. Det vanligaste sättet att behandla restless legs var att använda dopaminerga läkemedel samt bensodiazepiner, antiepileptika och opioider. Andra former av behandlingar var järn, homeopatiska läkemedel, hypnos samt fysisk aktivitet. Det förekom även att restless legs patienter på eget initiativ använde hasch eftersom det ansågs lindra symtomen.

Omvårdnadsåtgärder som stärker egenvården hos patienter med Irritable Bowel Syndrome

Syftet med denna systematiska litteraturstudie var att belysa hur sjuksköterskans omvårdnad kan stödja egenvårdsförmågan hos patienter med IBS. Den viktigaste omvårdnadsåtgärden var att tidigt i samband med diagnostiseringen av IBS, ge information och kunskap om sjukdomen, dess prognos samt behandling, vilket visades förbättra upplevd livskvalitet samt ge symtom-lindring. IBS skolor startade av sjuksköterskor förbättrade patienternas hälsobeteende samt minskade symtomen. Genom introduktion av guidebok innehållande råd om kost, motion, stresshantering samt symtomkontroll upplevde patienterna en minskning av symtom, vilket även ledde till en minskning av antalet besök inom sjukvården. När sjuksköterskan använde olika frågeformulär i kontakten med patienter med IBS kunde patienternas problem identifieras och strategier för egenvården planeras samt individuella handlingsplaner skapas. Sjuksköterskans kunskap och förståelse om patientens egen sjukdomsupplevelse samt copingstrategi ledde till att patienten tog en mer aktiv roll i sjukdomshantering. Patienters behandling borde inriktas på livsstilsförändringar, som till exempel psykosocial arbetsmiljö, kost, fysisk aktivitet, samt stresshantering. Genom att patienten förde dagbok över kostintag och sedan gjorde jämförelser med ökade eller minskade symtom kunde faktorer identifieras i matvanor samt kostintag som inverkade på symtomen. Dorotea Orems omvårdnadsmodell har legat till grund för denna studie där tron på människans egna resurser framhålls.

Study of Proteinuria: Isolation of Proteins from the Nephrotic Syndrome

One of the most puzzling phenomena of abnormal renal physiology is the occurrence of the nephrotic syndrome. The syndrome has been defined by a collection of clinical and pathological symptoms, but there is no correlation between the clinical and pathological symptoms nor is the etiology of the syndrome known. Proteinuria is probably the most distinguishing feature in the nephrotic syndrome, and there are two possible explanations for its occurrence: (1) the excessive amounts of protein found in nephrotic urine could be due to an increased basement membrane permeability in the glomerulus of the kidney or (2) dysproteinemia. An attempt has been made to evaluate the theory of dysproteinemia in connection with the syndrome. The albumin fractions of nephrotic urine have been studied for their amino acid composition by separating them from the urine by paper electrophoresis, hydrolyzing them, and identifying the amino acids present by two-dimensional chromatography. There seem to be no variations in the qualitative makeup of nephrotic albumin from that of normal albumin, but the literature shows that there are some slight variations in the quantitative amino acid composition of nephrotic albumin compared with normal albumin. More extensive and highly developed experimentation along the lines of protein structure and composition must be done before it can conclusively be stated that dysproteinemia is of importance in the nephrotic syndrome.