title: In vitro evaluation of Taxol combined with radiations in human squamous cell carcinoma spheroids.
abstract: The effect of Taxol on the radiation sensitivity of human squamous carcinoma of the head and neck region was determined in vitro, using clonogenic assays and multicellular tumor spheroids (MTS). Radiosensitivity parameters were determined by alpha and beta for clonogenic assays, and by the residual/control volume ratios at 2 Gy (RSV2) and the dose inducing 50% decrease in MTS number (SCD50) for spheroids. In HTB43 and CAL27 colonies, the combination was antagonist. In spheroids, Taxol induced a decrease of RSV2 and SCD50 in HTB43 and CAL27 MTS and their combinations with radiation were synergistic and additive, respectively. Therefore, the different results obtained by clonogenic assays and MTS may suggest higher drug incorporation through the multiple cell layers of the spheroids than in monolayers.
authors.affiliation: Laboratoire de Recherche en Oncologie, Centre Alexis Vautrin, Vandoeuvre-les-Nancy, France.
authors.forename: G
authors.initials: G
authors.lastname: Griffon-Etienne
authors.forename: J L
authors.initials: JL
authors.lastname: Merlin
authors.forename: C
authors.initials: C
authors.lastname: Marchal
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology* / Q000528:radiation effects; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D004307:Dose-Response Relationship, Radiation; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D017239:Paclitaxel / Q000494:pharmacology* / Q000528:radiation effects; D011836:Radiation Tolerance / Q000187:drug effects; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology* / Q000528:radiation effects; D018874:Spheroids, Cellular / Q000187:drug effects / Q000528:radiation effects; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000528:radiation effects
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D011838:Radiation-Sensitizing Agents; D017239:Paclitaxel