BACKGROUND: A new compound, betulinic acid, has been found to be cytotoxic against a variety of tumor cells originating from the neural crest. Its efficacy against head and neck squamous cellular carcinoma cell lines has so far not been tested. METHODS: Cell numbers were assayed by automated counting; caspase activation and programmed cell death were determined using an antibody specific for an apoptosis-associated epitope in epithelial cells. The expression pattern of Bcl-2 family members was assessed by Western blotting. RESULTS: In two HNSCC cell lines betulinic acid induced apoptosis, which was characterized by a dose-dependent reduction in cell numbers, emergence of apoptotic cells, and an increase in caspase activity. Western blot analysis of the expression of various Bcl-2 family members in betulinic acid-treated cells showed, surprisingly, a suppression of the expression of the proapoptotic protein Bax but no changes in Mcl-1 or Bcl-2 expression. CONCLUSION: These data clearly demonstrate for the first time that betulinic acid has apoptotic activity against HNSCC cells. Copyright 2003 Wiley Periodicals, Inc. Head Neck 25: 732-740, 2003
BACKGROUND: A new compound, betulinic acid, has been found to be cytotoxic against a variety of tumor cells originating from the neural crest. Its efficacy against head and neck squamous cellular carcinoma cell lines has so far not been tested. METHODS: Cell numbers were assayed by automated counting; caspase activation and programmed cell death were determined using an antibody specific for an apoptosis-associated epitope in epithelial cells. The expression pattern of Bcl-2 family members was assessed by Western blotting. RESULTS: In two HNSCC cell lines betulinic acid induced apoptosis, which was characterized by a dose-dependent reduction in cell numbers, emergence of apoptotic cells, and an increase in caspase activity. Western blot analysis of the expression of various Bcl-2 family members in betulinic acid-treated cells showed, surprisingly, a suppression of the expression of the proapoptotic protein Bax but no changes in Mcl-1 or Bcl-2 expression. CONCLUSION: These data clearly demonstrate for the first time that betulinic acid has apoptotic activity against HNSCC cells. Copyright 2003 Wiley Periodicals, Inc. Head Neck 25: 732-740, 2003
Authors: Christina Eder-Czembirek; Boban M Erovic; Cornelia Czembirek; Markus Brunner; Edgar Selzer; Richard Pötter; Dietmar Thurnher Journal: Strahlenther Onkol Date: 2010-02-22 Impact factor: 3.621
Authors: Wojciech Rzeski; Andrzej Stepulak; Marek Szymański; Marco Sifringer; Józef Kaczor; Katarzyna Wejksza; Barbara Zdzisińska; Martyna Kandefer-Szerszeń Journal: Naunyn Schmiedebergs Arch Pharmacol Date: 2006-09-09 Impact factor: 3.000