title: Efficacy of 5-aminolevulinic acid based photodynamic therapy in pituitary adenomas-experimental study on rat and human cell cultures.
abstract: BACKGROUND
  Incomplete resection of pituitary adenomas may result in recurrence. As adjuvant irradiation is not riskless, alternative treatment options should be investigated. 5-aminolevulinic acid based photodynamic therapy (5-ALA based PDT) showed promising results for malignant gliomas. The present study examined the efficacy of 5-ALA PDT in vitro on benign pituitary adenoma cell cultures.
  
  
  METHODS
  In group I experiments were performed on immortalized rat pituitary adenoma cells (GH3). The cultured cells were treated with different 5-ALA concentrations ranging from 7.5-16.5μg/ml. In Group II human pituitary adenoma cell cultures were obtained from surgically resected adenoma tissue (n=15). These were incubated with 5-ALA concentrations from 12.5-100μg/ml. The concentration ranges had been determined in preliminary dose-finding tests. For both groups incubation time was four hours and PDT was performed by exposition to laser light (635nm, 625s, 18.75J/cm(2)). Cell viability was examined by WST-1 assay.
  
  
  RESULTS
  In both groups PDT showed a 5-ALA concentration-dependent effect on cell death. In group I lower 5-ALA concentrations were necessary to destroy all cells as compared to group II. Moreover, in group II, the different subtypes of human adenomas showed different sensitivities to 5-ALA-based PDT (secreting vs. non-secreting). Especially corticotroph adenomas were highly sensitive to 5-ALA PDT.
  
  
  CONCLUSIONS
  The GH3 cell line was an useful in vitro model to optimize different PDT parameters. Human pituitary adenoma cells could also be killed by 5-ALA PDT, however this required higher 5-ALA concentrations. Furthermore, the results suggested different 5-ALA sensitivities between different human adenoma cell types. More experiments are necessary to confirm these preliminary results.
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany.
authors.forename: Lisa Margarete
authors.initials: LM
authors.lastname: Neumann
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany.
authors.forename: Kerim
authors.initials: K
authors.lastname: Beseoglu
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany.
authors.forename: Philipp Joerg
authors.initials: PJ
authors.lastname: Slotty
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Senger
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany.
authors.forename: Marcel Alexander
authors.initials: MA
authors.lastname: Kamp
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany; Department of Neurosurgery, Medical Faculty, Ruprecht-Karls-University Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Hänggi
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany.
authors.forename: Hans Jakob
authors.initials: HJ
authors.lastname: Steiger
authors.affiliation: Department of Neurosurgery, Medical Faculty, Heinrich-Heine-University, Moorenstraße 5, 40225 Düsseldorf, Germany. Electronic address: cornelius@hhu.de.
authors.forename: Jan Frederick
authors.initials: JF
authors.lastname: Cornelius
mesh_terms: D000236:Adenoma / Q000532:radiotherapy*; D000622:Aminolevulinic Acid; D000818:Animals; D001681:Biological Assay; D045744:Cell Line, Tumor; D002470:Cell Survival; D003124:Colorimetry; D004305:Dose-Response Relationship, Drug; D006801:Humans; D010778:Photochemotherapy; D010911:Pituitary Neoplasms / Q000532:radiotherapy; D051381:Rats
chemical_list: D000622:Aminolevulinic Acid
keywords: 5-ALA; PDT; Photodynamic therapy; Pituitary adenoma; Recurrence