{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T09:41:11Z","timestamp":1790674871406,"version":"4.1.0"},"reference-count":30,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,5,4]],"date-time":"2020-05-04T00:00:00Z","timestamp":1588550400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"La fabbrica dei sogni 2 - New developments for Rett syndrome","award":["---"],"award-info":[{"award-number":["---"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Among gliomas, primary tumors originating from glial cells, glioblastoma (GBM) identified as WHO grade IV glioma, is the most common and aggressive malignant brain tumor. We have previously shown that the Escherichia coli protein toxin cytotoxic necrotizing factor 1 (CNF1) is remarkably effective as an anti-neoplastic agent in a mouse model of glioma, reducing the tumor volume, increasing survival, and maintaining the functional properties of peritumoral neurons. However, being unable to cross the blood\u2013brain barrier (BBB), CNF1 requires injection directly into the brain, which is a very invasive administration route. Thus, to overcome this pitfall, we designed a CNF1 variant characterized by the presence of an N-terminal BBB-crossing tag. The variant was produced and we verified whether its activity was comparable to that of wild-type CNF1 in GBM cells. We investigated the signaling pathways engaged in the cell response to CNF1 variants to provide preliminary data to the subsequent studies in experimental animals. CNF1 may represent a novel avenue for GBM therapy, particularly because, besides blocking tumor growth, it also preserves the healthy surrounding tissue, maintaining its architecture and functionality. This renders CNF1 the most interesting candidate for the treatment of brain tumors, among other potentially effective bacterial toxins.<\/jats:p>","DOI":"10.3390\/toxins12050291","type":"journal-article","created":{"date-parts":[[2020,5,5]],"date-time":"2020-05-05T06:41:20Z","timestamp":1588660880000},"page":"291","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Cnf1 Variants Endowed with the Ability to Cross the Blood\u2013Brain Barrier: A New Potential Therapeutic Strategy for Glioblastoma"],"prefix":"10.3390","volume":"12","author":[{"given":"Andrea","family":"Colarusso","sequence":"first","affiliation":[{"name":"Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario M. S. Angelo, Via Cintia, 80126 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zaira","family":"Maroccia","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9002-5409","authenticated-orcid":false,"given":"Ermenegilda","family":"Parrilli","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario M. S. Angelo, Via Cintia, 80126 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena Angela Pia","family":"Germinario","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Fortuna","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Loizzo","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Ricceri","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4978-6839","authenticated-orcid":false,"given":"Maria Luisa","family":"Tutino","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario M. S. Angelo, Via Cintia, 80126 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1707-6282","authenticated-orcid":false,"given":"Carla","family":"Fiorentini","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"},{"name":"Association for Research on Integrative Oncological Therapies (ARTOI), 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3075-3367","authenticated-orcid":false,"given":"Alessia","family":"Fabbri","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanit\u00e0, Viale Regina Elena 299, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"803","DOI":"10.1007\/s00401-016-1545-1","article-title":"The 2016 world health organization classification of tumors of the central nervous system: A summary","volume":"131","author":"Louis","year":"2016","journal-title":"Acta Neuropathol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"334","DOI":"10.1016\/j.brainresbull.2019.09.012","article-title":"Glioblastoma: Targeting the autophagy in tumorigenesis","volume":"153","author":"Yang","year":"2019","journal-title":"Brain Res. Bull."},{"key":"ref_3","first-page":"e13138","article-title":"The Escherichia coli protein toxin cytotoxic necrotizing factor 1 induces epithelial mesenchymal transition","volume":"22","author":"Fabbri","year":"2019","journal-title":"Cell. Microbiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1634","DOI":"10.1093\/neuonc\/now114","article-title":"Electrophysiology of glioma: A Rho GTPase-activating protein reduces tumor growth and spares neuron structure and function","volume":"18","author":"Vannini","year":"2016","journal-title":"Neuro. Oncol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/j.freeradbiomed.2015.02.014","article-title":"Mitochondrial free radical overproduction due to respiratory chain impairment in the brain of a mouse model of Rett syndrome: Protective effect of CNF1","volume":"83","author":"Valenti","year":"2015","journal-title":"Free Radic. Biol. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1152","DOI":"10.1038\/npp.2011.301","article-title":"Modulation of RhoGTPases Improves the Behavioral Phenotype and Reverses Astrocytic Deficits in a Mouse Model of Rett Syndrome","volume":"37","author":"Fabbri","year":"2012","journal-title":"Neuropsychopharmacology"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1016\/j.euroneuro.2015.03.012","article-title":"Modulation of Rho GTPases rescues brain mitochondrial dysfunction, cognitive deficits and aberrant synaptic plasticity in female mice modeling Rett syndrome","volume":"25","author":"Valenti","year":"2015","journal-title":"Eur. Neuropsychopharmacol."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Loizzo, S., Rimondini, R., Travaglione, S., Fabbri, A., Guidotti, M., Ferri, A., Campana, G., and Fiorentini, C. (2013). CNF1 Increases Brain Energy Level, Counteracts Neuroinflammatory Markers and Rescues Cognitive Deficits in a Murine Model of Alzheimer\u2019s Disease. PLoS ONE, 8.","DOI":"10.1371\/annotation\/8da0f878-fcab-4f65-bad0-c5bdda8181ed"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Travaglione, S., Ballan, G., Fortuna, A., Ferri, A., Guidotti, M., Campana, G., Fiorentini, C., and Loizzo, S. (2015). CNF1 enhances brain energy content and counteracts spontaneous epileptiform phenomena in aged DBA\/2J mice. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0140495"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Vannini, E., Panighini, A., Cerri, C., Fabbri, A., Lisi, S., Pracucci, E., Benedetto, N., Vannozzi, R., Fiorentini, C., and Caleo, M. (2014). The bacterial protein toxin, cytotoxic necrotizing factor 1 (CNF1) provides long-term survival in a murine glioma model. BMC Cancer, 14.","DOI":"10.1186\/1471-2407-14-449"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"23539","DOI":"10.18632\/oncotarget.15328","article-title":"Progression of motor deficits in glioma-bearing mice: Impact of CNF1 therapy at symptomatic stages","volume":"8","author":"Vannini","year":"2017","journal-title":"Oncotarget"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1534","DOI":"10.1111\/j.1471-4159.2008.05492.x","article-title":"Involvement of the low-density lipoprotein receptor-related protein in the transcytosis of the brain delivery vector Angiopep-2","volume":"106","author":"Demeule","year":"2008","journal-title":"J. Neurochem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1002\/btpr.2574","article-title":"High yield purification and first structural characterization of the full-length bacterial toxin CNF1","volume":"34","author":"Colarusso","year":"2018","journal-title":"Biotechnol. Prog."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3473","DOI":"10.1111\/febs.12874","article-title":"Enhancement of mitochondrial ATP production by the Escherichia coli cytotoxic necrotizing factor 1","volume":"281","author":"Travaglione","year":"2014","journal-title":"FEBS J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1360","DOI":"10.1074\/jbc.M410176200","article-title":"67-kDa laminin receptor promotes internalization of cytotoxic necrotizing factor 1-expressing Escherichia coli K1 into human brain microvascular endothelial cells","volume":"280","author":"Kim","year":"2005","journal-title":"J. Biol. Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"16857","DOI":"10.1074\/jbc.M301028200","article-title":"37-kDa laminin receptor precursor modulates cytotoxic necrotizing factor 1-mediated RhoA activation and bacterial uptake","volume":"278","author":"Chung","year":"2003","journal-title":"J. Biol. Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.1091\/mbc.11.5.1775","article-title":"The p21 Rho-activating toxin cytotoxic necrotizing factor 1 is endocytosed by a clathrin-independent mechanism and enters the cytosol by an acidic-dependent membrane translocation step","volume":"11","author":"Contamin","year":"2000","journal-title":"Mol. Biol. Cell"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1835","DOI":"10.1128\/IAI.01145-08","article-title":"Cleavage of escherichia coli cytotoxic necrotizing factor 1 is required for full biologic activity","volume":"77","author":"Knust","year":"2009","journal-title":"Infect. Immun."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"28999","DOI":"10.1074\/jbc.274.41.28999","article-title":"Identification of the region of Rho involved in substrate recognition by Escherichia coli cytotoxic necrotizing factor 1 (CNF1)","volume":"274","author":"Lerm","year":"1999","journal-title":"J. Biol. Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"283","DOI":"10.3390\/toxins2020282","article-title":"Escherichia coli cytotoxic necrotizing factor 1 (CNF1): Toxin biology, in vivo applications and therapeutic potential","volume":"2","author":"Fabbri","year":"2010","journal-title":"Toxins (Basel)"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1016\/j.tiv.2006.08.013","article-title":"A multinucleating Escherichia coli cytotoxin perturbs cell cycle in cultured epithelial cells","volume":"21","author":"Travaglione","year":"2007","journal-title":"Toxicol. In Vitro"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Fabbri, A., Travaglione, S., Maroccia, Z., Guidotti, M., Pierri, C., Primiano, G., Servidei, S., Loizzo, S., and Fiorentini, C. (2018). The Bacterial Protein CNF1 as a Potential Therapeutic Strategy against Mitochondrial Diseases: A Pilot Study. Int. J. Mol. Sci., 19.","DOI":"10.3390\/ijms19071825"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1038\/nsmb0204-113","article-title":"Barreling through the membrane","volume":"11","author":"Johnson","year":"2004","journal-title":"Nat. Struct. Mol. Biol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"872","DOI":"10.1038\/nrm3013","article-title":"Mitochondrial fusion and fission in cell life and death","volume":"11","author":"Westermann","year":"2010","journal-title":"Nat. Rev. Mol. Cell Biol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Buc, E., Dubois, D., Sauvanet, P., Raisch, J., Delmas, J., Darfeuille-Michaud, A., Pezet, D., and Bonnet, R. (2013). High Prevalence of mucosa-associated E. coli producing cyclomodulin and genotoxin in colon cancer. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0056964"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"528","DOI":"10.1038\/nm0517-528","article-title":"Host with the most: Targeting host cells instead of pathogens to fight infectious disease","volume":"23","author":"Keener","year":"2017","journal-title":"Nat. Med."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1241","DOI":"10.1016\/j.nano.2016.01.004","article-title":"Rational engineering of single-chain polypeptides into protein-only, BBB-targeted nanoparticles","volume":"12","author":"Serna","year":"2016","journal-title":"Nanomedicine"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"13669","DOI":"10.1074\/jbc.273.22.13669","article-title":"The Rho-deamidating cytotoxic necrotizing factor 1 from Escherichia coli possesses transglutaminase activity. Cysteine 866 and histidine 881 are essential for enzyme activity","volume":"273","author":"Schmidt","year":"1998","journal-title":"J. Biol. Chem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1247","DOI":"10.1111\/j.1365-2958.1993.tb01254.x","article-title":"Induction of phagocytic behaviour in human epithelial cells by Escherichia coli cytotoxic necrotizing factor type 1","volume":"9","author":"Falzano","year":"1993","journal-title":"Mol. Microbiol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"680","DOI":"10.1038\/227680a0","article-title":"Cleavage of structural proteins during the assembly of the head of bacteriophage T4","volume":"227","author":"Laemmli","year":"1970","journal-title":"Nature"}],"container-title":["Toxins"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6651\/12\/5\/291\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T13:32:37Z","timestamp":1760362357000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6651\/12\/5\/291"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,5,4]]},"references-count":30,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2020,5]]}},"alternative-id":["toxins12050291"],"URL":"https:\/\/doi.org\/10.3390\/toxins12050291","relation":{},"ISSN":["2072-6651"],"issn-type":[{"value":"2072-6651","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,5,4]]}}}