Characterization of a novel PTEN mutation in MDA-MB-453 breast carcinoma cell line

<p>Abstract</p> <p>Background</p> <p>Cowden Syndrome (CS) patients with germ line point mutations in the <it>PTEN </it>gene are at high risk for developing breast cancer. It is believed that cells harboring these mutant <it>PTEN </it>alleles are predisposed to malignant conversion. This article will characterize the biochemical and biological properties of a mutant PTEN protein found in a commonly used metastatic breast cancer cell line.</p> <p>Methods</p> <p>The expression of PTEN in human breast carcinoma cell lines was evaluated by Western blotting analysis. Cell line MDA-MB-453 was selected for further analysis. Mutation analysis of the <it>PTEN </it>gene was carried out using DNA isolated from MDA-MB-453. Site-directed mutagenesis was used to generate a PTEN E307K mutant cDNA and ectopic expressed in PC3, U87MG, MCF7 and <it>Pten</it>^-/-mouse embryo fibroblasts (MEFS). Histidine (His)-tagged PTEN fusion protein was generated in <it>Sf9 </it>baculovirus expression system. Lipid phosphatase and ubiquitination assays were carried out to characterize the biochemical properties of PTEN E307K mutant. The intracellular localization of PTEN E307K was determined by subcellular fractionation experiments. The ability of PTEN E307K to alter cell growth, migration and apoptosis was analyzed in multiple PTEN-null cell lines.</p> <p>Results</p> <p>We found a mutation in the <it>PTEN </it>gene at codon 307 in MDA-MB-453 cell line. The glutamate (E) to lysine (K) substitution rendered the mutant protein to migrate with a faster mobility on SDS-PAGE gels. Biochemically, the PTEN E307K mutant displayed similar lipid phosphatase and growth suppressing activities when compared to wild-type (WT) protein. However, the PTEN E307K mutant was present at higher levels in the membrane fraction and suppressed Akt activation to a greater extent than the WT protein. Additionally, the PTEN E307K mutant was polyubiquitinated to a greater extent by NEDD4-1 and displayed reduced nuclear localization. Finally, the PTEN E307K mutant failed to confer chemosensitivity to cisplatinum when re-expressed in <it>Pten</it>^-/-MEFS.</p> <p>Conclusions</p> <p>Mutation at codon 307 in PTEN C2 loop alters its subcellular distribution with greater membrane localization while being excluded from the cell nucleus. This mutation may predispose breast epithelial cells to malignant transformation. Also, tumor cells harboring this mutation may be less susceptible to the cytotoxic effects of chemotherapeutics.</p

In COVID-19 Health Messaging, Loss Framing Increases Anxiety with Little-to-No Concomitant Benefits: Experimental Evidence from 84 Countries

The COVID-19 pandemic (and its aftermath) highlights a critical need to communicate health information effectively to the global public. Given that subtle differences in information framing can have meaningful effects on behavior, behavioral science research highlights a pressing question: Is it more effective to frame COVID-19 health messages in terms of potential losses (e.g., "If you do not practice these steps, you can endanger yourself and others") or potential gains (e.g., "If you practice these steps, you can protect yourself and others")? Collecting data in 48 languages from 15,929 participants in 84 countries, we experimentally tested the effects of message framing on COVID-19-related judgments, intentions, and feelings. Loss- (vs. gain-) framed messages increased self-reported anxiety among participants cross-nationally with little-to-no impact on policy attitudes, behavioral intentions, or information seeking relevant to pandemic risks. These results were consistent across 84 countries, three variations of the message framing wording, and 560 data processing and analytic choices. Thus, results provide an empirical answer to a global communication question and highlight the emotional toll of loss-framed messages. Critically, this work demonstrates the importance of considering unintended affective consequences when evaluating nudge-style interventions

Predominant role of DNA polymerase eta and p53-dependent translesion synthesis in the survival of ultraviolet-irradiated human cells

Genome lesions trigger biological responses that help cells manage damaged DNA, improving cell survival. Pol eta is a translesion synthesis (TLS) polymerase that bypasses lesions that block replicative polymerases, avoiding continued stalling of replication forks, which could lead to cell death. p53 also plays an important role in preventing cell death after ultraviolet (UV) light exposure. Intriguingly, we show that p53 does so by favoring translesion DNA synthesis by pol eta. In fact, the p53-dependent induction of pol eta in normal and DNA repair-deficient XP-C human cells after UV exposure has a protective effect on cell survival after challenging UV exposures, which was absent in p53- and Pol H-silenced cells. Viability increase was associated with improved elongation of nascent DNA, indicating the protective effect was due to more efficient lesion bypass by pol eta. This protection was observed in cells proficient or deficient in nucleotide excision repair, suggesting that, from a cell survival perspective, proper bypass of DNA damage can be as relevant as removal. These results indicate p53 controls the induction of pol eta in DNA damaged human cells, resulting in improved TLS and enhancing cell tolerance to DNA damage, which parallels SOS responses in bacteria.Fil: Lerner, Leticia K.. Universidade de Sao Paulo; BrasilFil: Francisco, Guilherme. Cancer Institute Of The State Of Sao Paulo; BrasilFil: Soltys, Daniela T.. Universidade de Sao Paulo; BrasilFil: Rocha, Clarissa R.R.. Universidade de Sao Paulo; BrasilFil: Quinet, Annabel. Universidade de Sao Paulo; BrasilFil: Vessoni, Alexandre T.. Universidade de Sao Paulo; BrasilFil: Castro, Ligia P.. Universidade de Sao Paulo; BrasilFil: David, Taynah I.P.. Universidade de Sao Paulo; BrasilFil: Bustos, Silvina O.. Cancer Institute Of The State Of Sao Paulo; BrasilFil: Strauss, Bryan E.. Universidade de Sao Paulo; BrasilFil: Gottifredi, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina. Fundación Instituto Leloir; ArgentinaFil: Stary, Anne. Centre National de la Recherche Scientifique; FranciaFil: Sarasin, Alain. Centre National de la Recherche Scientifique; FranciaFil: Chammas, Roger. Cancer Institute Of The State Of São Paulo; BrasilFil: Menck, Carlos F.M.. Universidade de Sao Paulo; Brasi

Author Correction: A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

Correction to: Nature Human Behaviour https://doi.org/10.1038/s41562-021-01173-x, published online 2 August 2021. In the version of this article initially published, the following authors were omitted from the author list and the Author contributionssection for “investigation” and “writing and editing”: Nandor Hajdu (Institute of Psychology, ELTE Eötvös Loránd University, Budapest,Hungary), Jordane Boudesseul (Facultad de Psicología, Instituto de Investigación Científica, Universidad de Lima, Lima, Perú), RafałMuda (Faculty of Economics, Maria Curie-Sklodowska University, Lublin, Poland) and Sandersan Onie (Black Dog Institute, UNSWSydney, Sydney, Australia & Emotional Health for All Foundation, Jakarta, Indonesia). In addition, Saeideh FatahModares’ name wasoriginally misspelled as Saiedeh FatahModarres in the author list. Further, affiliations have been corrected for Maria Terskova (NationalResearch University Higher School of Economics, Moscow, Russia), Susana Ruiz Fernandez (FOM University of Applied Sciences,Essen; Leibniz-Institut fur Wissensmedien, Tubingen, and LEAD Research Network, Eberhard Karls University, Tubingen, Germany),Hendrik Godbersen (FOM University of Applied Sciences, Essen, Germany), Gulnaz Anjum (Department of Psychology, Simon FraserUniversity, Burnaby, Canada, and Department of Economics & Social Sciences, Institute of Business Administration, Karachi, Pakistan)

Author correction: A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic

Correction to: Nature Human Behaviour https://doi.org/10.1038/s41562-021-01173-x, published online 2 August 2021. In the version of this article initially published, the following authors were omitted from the author list and the Author contributionssection for “investigation” and “writing and editing”: Nandor Hajdu (Institute of Psychology, ELTE Eötvös Loránd University, Budapest,Hungary), Jordane Boudesseul (Facultad de Psicología, Instituto de Investigación Científica, Universidad de Lima, Lima, Perú), RafałMuda (Faculty of Economics, Maria Curie-Sklodowska University, Lublin, Poland) and Sandersan Onie (Black Dog Institute, UNSWSydney, Sydney, Australia & Emotional Health for All Foundation, Jakarta, Indonesia). In addition, Saeideh FatahModares’ name wasoriginally misspelled as Saiedeh FatahModarres in the author list. Further, affiliations have been corrected for Maria Terskova (NationalResearch University Higher School of Economics, Moscow, Russia), Susana Ruiz Fernandez (FOM University of Applied Sciences,Essen; Leibniz-Institut fur Wissensmedien, Tubingen, and LEAD Research Network, Eberhard Karls University, Tubingen, Germany),Hendrik Godbersen (FOM University of Applied Sciences, Essen, Germany), Gulnaz Anjum (Department of Psychology, Simon FraserUniversity, Burnaby, Canada, and Department of Economics & Social Sciences, Institute of Business Administration, Karachi, Pakistan)

In COVID-19 Health Messaging, Loss Framing Increases Anxiety with Little-to-No Concomitant Benefits: Experimental Evidence from 84 Countries.

The COVID-19 pandemic (and its aftermath) highlights a critical need to communicate health information effectively to the global public. Given that subtle differences in information framing can have meaningful effects on behavior, behavioral science research highlights a pressing question: Is it more effective to frame COVID-19 health messages in terms of potential losses (e.g., "If you do not practice these steps, you can endanger yourself and others") or potential gains (e.g., "If you practice these steps, you can protect yourself and others")? Collecting data in 48 languages from 15,929 participants in 84 countries, we experimentally tested the effects of message framing on COVID-19-related judgments, intentions, and feelings. Loss- (vs. gain-) framed messages increased self-reported anxiety among participants cross-nationally with little-to-no impact on policy attitudes, behavioral intentions, or information seeking relevant to pandemic risks. These results were consistent across 84 countries, three variations of the message framing wording, and 560 data processing and analytic choices. Thus, results provide an empirical answer to a global communication question and highlight the emotional toll of loss-framed messages. Critically, this work demonstrates the importance of considering unintended affective consequences when evaluating nudge-style interventions