title: Somatostatin receptor scintigraphy with 111In-DOTA-lanreotide and 111In-DOTA-Tyr3-octreotide in patients with stage IV melanoma: in-vitro and in-vivo results.
abstract: The overexpression of somatostatin receptors (SST-Rs) on various tumour cells provides the molecular basis for the successful use of radiolabelled SST analogues in clinical oncology. The objective of the study was to evaluate the tumour binding of In-1,4,7,10-tetraazacyclo-dodecane-N,N',N'',N'''-tetraacetic acid-lanreotide (In-DOTA-LAN) and In-DOTA-tyrosine-octreotide (In-DOTA-Tyr-OCT) in patients with stage IV melanoma. In addition, we evaluated the potential antiproliferative effect of SST analogues, together with an assessment of the functionality of SST-Rs, on four melanoma cell lines. Twenty-three patients with advanced metastatic melanoma underwent scintigraphy. Thirty-eight of 61 lesions (62%) were positively imaged with In-DOTA-LAN, whereas 23 (37%) were negative. With In-DOTA-Tyr-OCT, 10 of the 23 documented lesions (43%) were positive and 13 (56%) were negative. In vitro, cell lines showed no growth inhibition in the presence of SST analogues and no influence on cell cycle distribution was found with the addition of SST analogues to cultured cells. In addition, no functional surface SST-Rs could be demonstrated on these cell lines. Taken together, our results demonstrate the visualization of metastatic melanoma in a high percentage of patients, probably due to binding of SST analogues to SST-Rs on tumour vessels or infiltrating immune cells. Judging from our data, however, there is no evidence of functional SST-R expression on melanoma cells.
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria. julia.valencak@meduniwien.ac.at
authors.forename: Julia
authors.initials: J
authors.lastname: Valencak
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Heere-Ress
authors.forename: Tatjana
authors.initials: T
authors.lastname: Traub-Weidinger
authors.forename: Markus
authors.initials: M
authors.lastname: Raderer
authors.forename: Achim
authors.initials: A
authors.lastname: Schneeberger
authors.forename: Theresia
authors.initials: T
authors.lastname: Thalhammer
authors.forename: Sylvia
authors.initials: S
authors.lastname: Aust
authors.forename: Gerhard
authors.initials: G
authors.lastname: Hamilton
authors.forename: Irene
authors.initials: I
authors.lastname: Virgolini
authors.forename: Hubert
authors.initials: H
authors.lastname: Pehamberger
mesh_terms: D000328:Adult; D000368:Aged; D045744:Cell Line, Tumor; D005260:Female; D006571:Heterocyclic Compounds / Q000493:pharmacokinetics; D006801:Humans; D007205:Indium Radioisotopes; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D009367:Neoplasm Staging; D015282:Octreotide / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D010456:Peptides, Cyclic / Q000493:pharmacokinetics; D011877:Radionuclide Imaging / Q000379:methods; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D017481:Receptors, Somatostatin / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D006571:Heterocyclic Compounds; D007205:Indium Radioisotopes; D010456:Peptides, Cyclic; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; C116409:indium 111-DOTA-lanreotide; C121107:octreotide, DOTA-Tyr(3)-; D015282:Octreotide