title: Expression of gp100 in melanoma metastases resected before or after treatment with IFN alpha and IL-2.
abstract: The melanosomal protein gp100 was recently described as an antigen associated with tumor rejection in adoptive immunotherapy using tumor-infiltrating lymphocytes. In this study, we investigated whether the expression of gp100 in melanoma cells correlates with responsiveness to treatment with interferon-alpha and interleukin-2. Using the monoclonal antibody HMB-45 recognizing gp100, we examined metastatic tissue resected before therapy in 44 patients with melanoma including 9 patients with subsequent complete or partial remission. A very heterogeneous pattern of gp100-expression was found between patients, but the percentage of gp-100 positive cells in different metastases resected from the same patient was rather constant. This suggests that the gp100 expression determined in a single metastasis may be judged as being representative for other metastatic lesions of a patient. We found no correlation between expression of gp100 and responsiveness to subsequent immunotherapy. Our results show that the lack of gp100 before therapy is not associated with decreased responsiveness to subsequent cytokine treatment.
authors.affiliation: Department of Internal Medicine V (Hematology/Oncology/Rheumatology), University of Heidelberg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Scheibenbogen
authors.forename: I
authors.initials: I
authors.lastname: Weyers
authors.forename: D
authors.initials: D
authors.lastname: Ruiter
authors.forename: M
authors.initials: M
authors.lastname: Willhauck
authors.forename: A
authors.initials: A
authors.lastname: Bittinger
authors.forename: U
authors.initials: U
authors.lastname: Keilholz
mesh_terms: D000951:Antigens, Neoplasm / Q000096:biosynthesis*; D006801:Humans; D016233:Immunotherapy, Active; D016898:Interferon-alpha / Q000627:therapeutic use*; D007376:Interleukin-2 / Q000627:therapeutic use*; D008545:Melanoma / Q000737:chemistry* / Q000473:pathology / Q000556:secondary / Q000628:therapy*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D058951:gp100 Melanoma Antigen
chemical_list: D000951:Antigens, Neoplasm; D016898:Interferon-alpha; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; C548637:PMEL protein, human; D058951:gp100 Melanoma Antigen