title: The effect of resveratrol in combination with irradiation and chemotherapy: study using Merkel cell carcinoma cell lines.
abstract: OBJECTIVE
  Merkel cell carcinoma (MCC) is a rare, but highly malignant tumor of the skin. In case of systemic disease, possible therapeutic options include irradiation or chemotherapy. The aim of this study was to evaluate whether the flavonoid resveratrol enhances the effect of radiotherapy or chemotherapy in MCC cell lines.
  
  
  METHODS
  The two MCC cell lines MCC13 and MCC26 were treated with increasing doses of resveratrol. Combination experiments were conducted with cisplatin and etoposide. Colony forming assays were performed after sequential irradiation with 1, 2, 3, 4, 6, and 8 Gy and apoptosis was assessed with flow cytometry. Expression of cancer drug targets was analyzed by real-time PCR array.
  
  
  RESULTS
  Resveratrol is cytotoxic in MCC cell lines. Cell growth is inhibited by induction of apoptosis. The combination with cisplatin and etoposide resulted in a partially synergistic inhibition of cell proliferation. Resveratrol and irradiation led to a synergistic reduction in colony formation compared to irradiation alone. Evaluation of gene expression did not show significant difference between the cell lines.
  
  
  CONCLUSIONS
  Due to its radiosensitizing effect, resveratrol seems to be a promising agent in combination with radiation therapy. The amount of chemosensitizing depends on the cell lines tested.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Heiduschka
authors.forename: C
authors.initials: C
authors.lastname: Lill
authors.forename: R
authors.initials: R
authors.lastname: Seemann
authors.forename: M
authors.initials: M
authors.lastname: Brunner
authors.forename: R
authors.initials: R
authors.lastname: Schmid
authors.forename: R
authors.initials: R
authors.lastname: Houben
authors.forename: J
authors.initials: J
authors.lastname: Bigenzahn
authors.forename: D
authors.initials: D
authors.lastname: Thurnher
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D015266:Carcinoma, Merkel Cell / Q000473:pathology* / Q000628:therapy*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D059248:Chemoradiotherapy / Q000379:methods*; D002945:Cisplatin / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005047:Etoposide / Q000008:administration & dosage; D006801:Humans; D000077185:Resveratrol; D013267:Stilbenes / Q000008:administration & dosage*; D016896:Treatment Outcome
chemical_list: D013267:Stilbenes; D005047:Etoposide; D002945:Cisplatin; D000077185:Resveratrol