title: Two coffins and a funeral: early or late caspase activation determines two types of apoptosis induced by DNA damaging agents.
abstract: Cell cytoskeleton makes profound changes during apoptosis including the organization of an Apoptotic Microtubule Network (AMN). AMN forms a cortical structure which plays an important role in preserving plasma membrane integrity during apoptosis. Here, we examined the cytoskeleton rearrangements during apoptosis induced by camptothecin (CPT), a topoisomerase I inhibitor, in human H460 and porcine LLCPK-1α cells. Using fixed and living cell imaging, we showed that CPT induced two dose- and cell cycle-dependent types of apoptosis characterized by different cytoskeleton reorganizations, time-dependent caspase activation and final apoptotic cell morphology. In the one referred as "slow" (~h) or round-shaped, apoptosis was characterized by a slow contraction of the actinomyosin ring and late caspase activation. In "slow" apoptosis the γ-tubulin complexes were not disorganized and microtubules were not depolymerized at early stages. In contrast, "fast" (~min) or irregular-shaped apoptosis was characterized by early caspase activation followed by full contraction of the actinomyosin ring. In fast apoptosis γ-tubulin complexes were disorganized and microtubules were initially depolymerized. However, after actinomyosin contraction, microtubules were reformed adopting a cortical but irregular disposition near plasma membrane. In addition to distinctive cytoskeleton reorganization kinetics, round and irregular-shaped apoptosis showed different biological properties with respect to AMN maintenance, plasma membrane integrity and phagocytes response. Our results suggest that the knowledge and modulation of the type of apoptosis promoted by genotoxic agents may be important for deciding a better therapeutic option and predicting the immune response in cancer treatment.
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Oropesa-Ávila
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: de la Cruz-Ojeda
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Porcuna
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Villanueva-Paz
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Fernández-Vega
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Mario
authors.initials: M
authors.lastname: de la Mata
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: de Lavera
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Juan Miguel Suarez
authors.initials: JM
authors.lastname: Rivero
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Luzón-Hidalgo
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Álvarez-Córdoba
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Cotán
authors.affiliation: Sistemas Físicos, Químicos y Naturales-Universidad Pablo de Olavide, 41013, Sevilla, Spain.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Zaderenko
authors.affiliation: Facultad de Odontología, Universidad de Sevilla, 41009, Sevilla, Spain.
authors.forename: Mario D
authors.initials: MD
authors.lastname: Cordero
authors.affiliation: Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Carretera de Utrera Km 1, 41013, Sevilla, Spain. jasanalc@upo.es.
authors.forename: José A
authors.initials: JA
authors.lastname: Sánchez-Alcázar
mesh_terms: D000205:Actomyosin / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D002166:Camptothecin / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000187:drug effects; D048430:Cell Shape; D003599:Cytoskeleton / Q000187:drug effects* / Q000502:physiology; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D006801:Humans; D018374:LLC-PK1 Cells; D008870:Microtubules / Q000187:drug effects / Q000648:ultrastructure; D010587:Phagocytosis / Q000187:drug effects; D013552:Swine; D059004:Topoisomerase I Inhibitors / Q000494:pharmacology*; D014404:Tubulin / Q000187:drug effects
chemical_list: D059004:Topoisomerase I Inhibitors; D014404:Tubulin; D000205:Actomyosin; D002166:Camptothecin
keywords: Actin; Apoptosis; Camptothecin; Caspases; Microtubules