title: Tomentosin Induces Telomere Shortening and Caspase-Dependant Apoptosis in Cervical Cancer Cells.
abstract: Tomentosin, a natural sesquiterpene lactone purified from of Inula viscosa L., was investigated for its anti-proliferative, telomere shortening, and apoptotic effects on human cervical cancer HeLa and SiHa cell lines. Tomentosin was found to inhibit the growth of SiHa and HeLa cell lines in dose and time-dependent manner (IC50values of 7.10 ± 0.78 μM and 5.87 ± 0.36 μM, respectively after 96 h of treatment). As evidenced by TTAGGG telomere length assay, tomentosin target specifically the telomeric overhang lengthening. This was confirmed by the evaluation of the cytotoxic effects of tomentosin in the foetal fibroblast Wi38 and JW10 cells which were derived from Wi38 and express hTERT, the telomerase catalytic subunit. We found that JW10 cells are 4.7-fold more sensitive to tomentosin which argues for telomere as its specific target. Furthermore, we found that tomentosin mediate this cytotoxic effect by inducing apoptosis and cell cycle arrest at G2/M phase. Morphological features of treated cells, as evidenced by Hoechst 33324 staining, revealed that the cytotoxic effect was due to induction of apoptosis. This was accompanied by pro-caspase-3 cleavage, an increase in caspase-3 activity and a cleavage of poly (ADP-ribose) polymerase (PARP). Moreover, tomentosin induced a decrease in mitochondrial membrane potential (ΔΨm) and an increase in reactive oxygen species (ROS), accompanied by a decrease in Bcl-2 expression. This indicates that tomentosin-induced apoptosis may involve a mitochondria-mediated signaling pathway. This study provides the first evidence that tomentosin targets telomere machinery and induces apoptosis in cervical cancer cells. The molecular mechanism underlying tomentosin-induced apoptosis may involve a mitochondria-mediated signaling pathway. J. Cell. Biochem. 118: 1689-1698, 2017. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Laboratoire de Biochimie-Immunologie, Faculté des Sciences de Rabat, Agdal, Morocco.|Unité Biologie & Recherche Médicale CNESTEN, Rabat, Morocco.|MEDyC CNRS UMR7369, UFR Sciences, UFR Médecine et UFR Pharmacie, Reims, France.|Green Biotechnology Center, MAScIR (Moroccan foundation for Advanced Science, Innovation and Research), Rabat, Morocco.
authors.forename: Nawel
authors.initials: N
authors.lastname: Merghoub
authors.affiliation: MEDyC CNRS UMR7369, UFR Sciences, UFR Médecine et UFR Pharmacie, Reims, France.
authors.forename: Hassan
authors.initials: H
authors.lastname: El Btaouri
authors.affiliation: Unité Biologie & Recherche Médicale CNESTEN, Rabat, Morocco.
authors.forename: Laila
authors.initials: L
authors.lastname: Benbacer
authors.affiliation: Centre National Pour la Recherche Scientifique et Technique, Rabat, Morocco.
authors.forename: Saïd
authors.initials: S
authors.lastname: Gmouh
authors.affiliation: University of Reims and MNHN, INSERM U565, CNRS UMR 7196, 75005, Paris, France.
authors.forename: Chantal
authors.initials: C
authors.lastname: Trentesaux
authors.affiliation: MEDyC CNRS UMR7369, UFR Sciences, UFR Médecine et UFR Pharmacie, Reims, France.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Brassart
authors.affiliation: Unité Biologie & Recherche Médicale CNESTEN, Rabat, Morocco.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Attaleb
authors.affiliation: MEDyC CNRS UMR7369, UFR Sciences, UFR Médecine et UFR Pharmacie, Reims, France.
authors.forename: Claudie
authors.initials: C
authors.lastname: Madoulet
authors.affiliation: Laboratoire de Pathologie de la cellule B Indolente, UMR CNRS 5239, Faculté de Médecine Lyon Sud, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wenner
authors.affiliation: Laboratoire de Biochimie-Immunologie, Faculté des Sciences de Rabat, Agdal, Morocco.
authors.forename: Saaid
authors.initials: S
authors.lastname: Amzazi
authors.affiliation: MEDyC CNRS UMR7369, UFR Sciences, UFR Médecine et UFR Pharmacie, Reims, France.
authors.forename: Hamid
authors.initials: H
authors.lastname: Morjani
authors.affiliation: Unité Biologie & Recherche Médicale CNESTEN, Rabat, Morocco.
authors.forename: Mohamed
authors.initials: M
authors.lastname: El Mzibri
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D015153:Blotting, Western; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000187:drug effects / Q000235:genetics; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000235:genetics; D005260:Female; D016195:G2 Phase / Q000187:drug effects / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D007783:Lactones / Q000494:pharmacology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D012717:Sesquiterpenes / Q000494:pharmacology*; D016615:Telomere / Q000187:drug effects / Q000235:genetics*; D002583:Uterine Cervical Neoplasms / Q000235:genetics*
chemical_list: D007783:Lactones; D017382:Reactive Oxygen Species; D012717:Sesquiterpenes; C454646:tomentosin; D053148:Caspase 3
keywords: APOPTOSIS; CERVICAL CANCER; CYTOTOXICITY; TELOMERE SHORTENING; TOMENTOSIN