title: Interleukin-10 production in malignant melanoma: preferential detection of IL-10-secreting tumor cells in metastatic lesions.
abstract: IL-10 mRNA expression and protein production in established melanoma cell lines and freshly cultured primary and metastatic melanoma cells was examined. The in situ distribution of IL-10 in native melanoma tissue was also investigated by immunohistochemistry in primary tumors, metastases, benign melanocytic nevi and normal skin of healthy persons and melanoma patients. IL-10 mRNA, but not IL-10 protein in the culture supernatant, was found in 1 of 4 cultured melanoma cells of primary tumors, while 3 of 6 melanoma-metastasis-derived cultures expressed both IL-10 mRNA and protein. No IL-10 was detected in skin biopsies of healthy volunteers or in the healthy skin of melanoma patients; nor was IL-10 found in congenital melanocytic nevi. In only 1 of the 11 examined primary malignant melanomas was IL-10 immunoreactivity detected within the cytoplasm of cells in the tumor. On the other hand, 4 of 9 metastases clearly displayed scattered IL-1O+ cells. In all sections with IL-10-positive cells, the cells were positive for HMB-45. No co-expression of CD3 and IL-10 was observed. The data suggest that melanoma cells themselves are the main origin of IL-10 in tumor specimens in vivo. The preferential expression of IL-10 in metastatic lesions and in cultured cells from metastases might indicate an increased spreading potential of IL-10-secreting melanoma-cell clones.
authors.affiliation: Department of Dermatology, University of Würzburg, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Dummer
authors.forename: B C
authors.initials: BC
authors.lastname: Bastian
authors.forename: N
authors.initials: N
authors.lastname: Ernst
authors.forename: C
authors.initials: C
authors.lastname: Schänzle
authors.forename: A
authors.initials: A
authors.lastname: Schwaaf
authors.forename: E B
authors.initials: EB
authors.lastname: Bröcker
mesh_terms: D001483:Base Sequence; D001706:Biopsy; D006801:Humans; D016753:Interleukin-10 / Q000032:analysis / Q000096:biosynthesis* / Q000378:metabolism; D008545:Melanoma / Q000378:metabolism* / Q000556:secondary*; D008969:Molecular Sequence Data; D009506:Nevus / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012867:Skin / Q000737:chemistry; D012878:Skin Neoplasms / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D012333:RNA, Messenger; D016753:Interleukin-10