title: A tryptophanol-derived oxazolopiperidone lactam is cytotoxic against tumors via inhibition of p53 interaction with murine double minute proteins.
abstract: Inactivation of the p53 tumor suppressor protein by interaction with murine double minute (MDM) proteins, MDM2 and MDMX, is a common event in human tumors expressing wild-type p53. In these tumors, the simultaneous inhibition of these interactions with MDMs, for a full p53 reactivation, represents a promising anticancer strategy. Herein, we report the identification of a dual inhibitor of the p53 interaction with MDM2 and MDMX, the (S)-tryptophanol derivative OXAZ-1, from the screening of a small library of enantiopure tryptophanol-derived oxazolopiperidone lactams, using a yeast-based assay. With human colon adenocarcinoma HCT116 cell lines expressing wild-type p53 (HCT116 p53(+/+)) and its p53-null isogenic derivative (HCT116 p53(-/-)), it was shown that OXAZ-1 induced a p53-dependent tumor growth-inhibitory effect. In fact, OXAZ-1 induced p53 stabilization, up-regulated p53 transcription targets, such as MDM2, MDMX, p21, Puma and Bax, and led to PARP cleavage, in p53(+/+), but not in p53(-/-), HCT116 cells. In addition, similar tumor cytotoxic effects were observed for OXAZ-1 against MDMX-overexpressing breast adenocarcinoma MCF-7 tumor cells, commonly described as highly resistant to MDM2-only inhibitors. In HCT116 p53(+/+) cells, the disruption of the p53 interaction with MDMs by OXAZ-1 was further confirmed by co-immunoprecipitation. It was also shown that OXAZ-1 potently triggered a p53-dependent mitochondria-mediated apoptosis, characterized by reactive oxygen species generation, mitochondrial membrane potential dissipation, Bax translocation to mitochondria, and cytochrome c release, and exhibited a p53-dependent synergistic effect with conventional chemotherapeutic drugs. Collectively, in this work, a novel selective activator of the p53 pathway is reported with promising antitumor properties to be explored either alone or combined with conventional chemotherapeutic drugs. Moreover, OXAZ-1 may represent a promising starting scaffold to search for new dual inhibitors of the p53-MDMs interaction.
authors: UCIBIO/REQUIMTE, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313 Porto, Portugal; Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313, Porto, Portugal.
authors: Joana
authors: J
authors: Soares
authors: UCIBIO/REQUIMTE, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313 Porto, Portugal; Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313, Porto, Portugal.
authors: Liliana
authors: L
authors: Raimundo
authors: Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal.
authors: Nuno A L
authors: NA
authors: Pereira
authors: REQUIMTE, Departamento de Química e Bioquímica, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal.
authors: Daniel J V A
authors: DJ
authors: dos Santos
authors: Laboratory of Organic Chemistry, Faculty of Pharmacy and Institute of Biomedicine, University of Barcelona, Av. Joan XXIII, s/n, 08028 Barcelona, Spain.
authors: Maria
authors: M
authors: Pérez
authors: UCIBIO/REQUIMTE, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313 Porto, Portugal; Laboratório de Farmacologia, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313, Porto, Portugal.
authors: Glória
authors: G
authors: Queiroz
authors: UCIBIO/REQUIMTE, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313 Porto, Portugal; Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313, Porto, Portugal.
authors: Mariana
authors: M
authors: Leão
authors: Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal. Electronic address: mariasantos@ff.ulisboa.pt.
authors: Maria M M
authors: MM
authors: Santos
authors: UCIBIO/REQUIMTE, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313 Porto, Portugal; Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 164, 4050-313, Porto, Portugal. Electronic address: lucilia.saraiva@ff.up.pt.
authors: Lucília
authors: L
authors: Saraiva
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D018797:Cell Cycle Proteins; D002470:Cell Survival / Q000187:drug effects; D004357:Drug Synergism; D045325:HCT116 Cells; D006801:Humans; D061986:MCF-7 Cells; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D015394:Molecular Structure; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010080:Oxazoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D010881:Piperidones / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000737:chemistry; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D018797:Cell Cycle Proteins; C482775:MDM4 protein, human; D009687:Nuclear Proteins; C000605896:OXAZ-1 compound; D010080:Oxazoles; D010881:Piperidones; D011518:Proto-Oncogene Proteins; D017382:Reactive Oxygen Species; D016159:Tumor Suppressor Protein p53; C069544:tryptophanol; D014364:Tryptophan; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2
keywords: Antitumor activity; Doxorubicin (PubChem CID: 443939); Etoposide (PubChem CID: 36462); Mitochondria-mediated apoptosis; Murine double minute proteins; Nutlin-3a (PubChem CID: 11433190); Oxazolopiperidone lactam; SJ-172550 (PubChem CID: 1317464); p53; p53–MDMs interaction