title: 5-Aminolevulinic acid-induced fluorescence in bronchial tumours: dependency on the patterns of tumour invasion.
abstract: 5-ALA-induced protoporphyrin IX (PPIX) fluorescence kinetics was quantified by fluorescence microscopy in three-dimensional organ co-cultures of human bronchial epithelium, which were infiltrated by four different lung tumour cell lines (EPLC-M31, LCLC-103H, NCI-H125 and NCI-H841). Corresponding fluorescence measurements were performed in monolayer cultures of these tumour cell lines and BEAS-2B cells as a model for normal bronchial epithelium by flow cytometry. Significant differences of fluorescence intensities (FI) between the tumours were detected in organ co-cultures as well as in single cell measurements. Relative FI values in organ co-cultures (FI(EPLC-32M1)>FI(LCLC-H103)>FI(NCI-H125)>FI(NCI-H841)) did not correspond to the measurements in single cells (FI(LCLC-H103)>FI(NCI-H125)>FI(NCI-H841)>FI(EPLC-32M1)). Histology of organ co-cultures revealed different patterns of invasion and tumour cell densities depending on the tumour type. After correction of FI in the co-cultures to tumour cell density the correlation coefficient for fluorescence values between both models increased considerably. Thus, additionally to distinctive features of 5-ALA metabolism, patterns of tumour invasion may be a factor determining 5-ALA-induced fluorescence. Considering these results, a pronounced heterogeneity of 5-ALA-induced fluorescence might be expected in different bronchial tumours in vivo. This could interfere with the diagnostic reliability of 5-ALA-induced fluorescence for early tumour detection.
authors.affiliation: Medizinische Klinik--Innenstadt, Klinikum der Ludwig-Maximilians-Universität, Ziemssenstr. 1, 80336 München, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Gamarra
authors.forename: P
authors.initials: P
authors.lastname: Lingk
authors.forename: A
authors.initials: A
authors.lastname: Marmarova
authors.forename: M
authors.initials: M
authors.lastname: Edelmann
authors.forename: H
authors.initials: H
authors.lastname: Hautmann
authors.forename: H
authors.initials: H
authors.lastname: Stepp
authors.forename: R
authors.initials: R
authors.lastname: Baumgartner
authors.forename: R M
authors.initials: RM
authors.lastname: Huber
mesh_terms: D000622:Aminolevulinic Acid / Q000737:chemistry*; D001984:Bronchial Neoplasms / Q000737:chemistry* / Q000473:pathology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000737:chemistry / Q000473:pathology; D045744:Cell Line, Tumor; D005453:Fluorescence; D006801:Humans; D008175:Lung Neoplasms / Q000737:chemistry / Q000473:pathology; D009361:Neoplasm Invasiveness; D017319:Photosensitizing Agents / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid