title: Expression of miR-155 and miR-126 in situ in cutaneous T-cell lymphoma.
abstract: Recently, miR-155 has been implicated in cutaneous T-cell lymphoma (CTCL). Thus, elevated levels of miR-155 were observed in skin lesions from CTCL patients as judged from qPCR and micro-array analysis and aberrant, high miR-155 expression was associated with severe disease. Moreover, miR-155 promoted proliferation of malignant T cells in vitro. Little is, however, known about which cell types express miR-155 in vivo in CTCL skin lesions. Here, we study miR-155 expression using in situ hybridization (ISH) with a miR-155 probe, a negative control (scrambled), and a miR-126 probe as a positive control in nine patients with mycosis fungoides, the most frequent subtype of CTCL. We provide evidence that both malignant and non-malignant T cells stain weakly to moderately positive with the miR-155 probe, but generally negative with the miR-126 and negative control probes. Reversely, endothelial cells stain positive for miR-126 and negative for miR-155 and the control probe. Solitary T cells with a malignant morphology display brighter staining with the miR-155 probe. Taken together, our findings suggest that both malignant and non-malignant T cells express miR-155 in situ in CTCL. Moreover, they indicate heterogeneity in miR-155 expression among malignant T cells.
authors.affiliation: Department of International Health, Immunology and Microbiology (UoC), Copenhagen, Denmark.
authors.forename: Katharina L
authors.initials: KL
authors.lastname: Kopp
authors.forename: Ulrik
authors.initials: U
authors.lastname: Ralfkiaer
authors.forename: Boye S
authors.initials: BS
authors.lastname: Nielsen
authors.forename: Robert
authors.initials: R
authors.lastname: Gniadecki
authors.forename: Anders
authors.initials: A
authors.lastname: Woetmann
authors.forename: Niels
authors.initials: N
authors.lastname: Ødum
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Ralfkiaer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D016410:Lymphoma, T-Cell, Cutaneous / Q000235:genetics*; D008297:Male; D035683:MicroRNAs / Q000032:analysis / Q000502:physiology*; D008875:Middle Aged; D012878:Skin Neoplasms / Q000235:genetics*
chemical_list: C527111:MIRN126 microRNA, human; C524942:MIRN155 microRNA, human; D035683:MicroRNAs
keywords: CTCL; ISH; miR-126; miR-155; miRNA