title: MicroRNA-181b negatively regulates the proliferation of human epidermal keratinocytes in psoriasis through targeting TLR4.
abstract: Our study aims to explore the role of microRNA-181b (miR-181b) and TLR in the regulation of cell proliferation of human epidermal keratinocytes (HEKs) in psoriasis. Twenty-eight patients diagnosed with psoriasis vulgaris were selected as a case group with their lesional and non-lesional skin tissues collected. A control group consisted of 20 patients who underwent plastic surgery with their healthy skin tissues collected. Real-time quantitative fluorescence polymerase chain reaction (RT-qPCR), in situ hybridization and immunohistochemistry were used to detect the expressions of miR-181b and TLR4 in HEKs of healthy skin, psoriatic lesional skin and non-lesional skin respectively. The 3' untranslated region (3'UTR) of TLR4 combined with miR-181b was verified by a dual-luciferase reporter assay. Western blotting and bromodeoxyuridine were applied for corresponding detection of TLR4 expression and cell mitosis. The expression of miR-181b in HEKs of psoriatic lesional skin was less than healthy skin and psoriatic non-lesional skin. In psoriatic lesional and non-lesional skin, TLR4-positive cell rates and the number of positive cells per square millimetre were higher than healthy skin. The dual-luciferase reporter assay verified that miR-181b targets TLR4. HEKs transfected with miR-181b mimics had decreased expression of TLR4, along with the decrease of mitotic indexes and Brdu labelling indexes. However, HEKs transfected with miR-181b inhibitors showed increased TLR4 expression, mitotic indexes and Brdu labelling indexes. HEKs transfected with both miR-181b inhibitors and siTLR4 had decreased mitotic indexes and Brdu labelling indexes. These results indicate that miR-181b can negatively regulate the proliferation of HEKs in psoriasis by targeting TLR4.
authors.affiliation: Aesthetic Plastic Department of Peking Union Medical Collage Hospital, Beijing, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Feng
authors.affiliation: Aesthetic Plastic Department of Peking Union Medical Collage Hospital, Beijing, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Bai
authors.affiliation: Aesthetic Plastic Department of Peking Union Medical Collage Hospital, Beijing, China.
authors.forename: Nan-Ze
authors.initials: NZ
authors.lastname: Yu
authors.affiliation: Aesthetic Plastic Department of Peking Union Medical Collage Hospital, Beijing, China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Wang
authors.affiliation: Aesthetic Plastic Department of Peking Union Medical Collage Hospital, Beijing, China.
authors.forename: Zeng
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000328:Adult; D001483:Base Sequence; D049109:Cell Proliferation / Q000235:genetics; D004817:Epidermis / Q000473:pathology*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D011565:Psoriasis / Q000235:genetics* / Q000473:pathology*; D015203:Reproducibility of Results; D051197:Toll-Like Receptor 4 / Q000235:genetics* / Q000378:metabolism
chemical_list: C540193:MIrn181 microRNA, human; D035683:MicroRNAs; D051197:Toll-Like Receptor 4
keywords: 
  TLR4
  ; Western blotting; immunohistochemistry; keratinocytes; microRNA-181b; psoriasis; psoriatic lesions; qRT-PCR