title: Osteopontin expression in normal skin and non-melanoma skin tumors.
abstract: Osteopontin (OPN) is an adhesive, matricellular glycoprotein, whose expression is elevated in many types of cancer and has been shown to facilitate tumorigenesis in vivo. To understand the role of OPN in human skin cancer, this study is designed to determine whether OPN is expressed in premalignant [solar/actinic keratosis (AK)] and in malignant skin lesions such as squamous cell carcinomas (SCC) and basal cell carcinomas (BCC), as well as in normal skin exposed or not exposed to sunlight. Immunohistochemical analyses showed that OPN is expressed in SCC (20/20 cases) and in AK (16/16 cases), which are precursors to SCC, but is absent or minimally expressed in solid BCC (17 cases). However, positive staining for OPN was observed in those BCC that manifest differentiation toward epidermal appendages such as keratotic BCC. In sunlight-exposed normal skin, OPN is minimally expressed in the basal cell layer, but in contrast to those not exposed to sunlight, OPN is more prominent in the spinous cell layer with increasing intensity toward the granular cell layer. Additionally, OPN is expressed in the hair follicles, sebaceous glands, and sweat glands of normal skin. In conclusion, these data suggest that OPN is associated with keratinocyte differentiation and that it is expressed in AK and SCC, which have metastatic potential, but minimally expressed in solid BCC.
authors.affiliation: Department of Nutrition Sciences, 311 Susan Mott Webb Nutrition Sciences Building, 1675 University Boulevard, University of Alabama at Birmingham, Birmingham, Alabama 35295-3360, USA. plchang@uab.edu
authors.forename: Pi-Ling
authors.initials: PL
authors.lastname: Chang
authors.forename: Louie
authors.initials: L
authors.lastname: Harkins
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Hsieh
authors.forename: Patricia
authors.initials: P
authors.lastname: Hicks
authors.forename: Kraisorn
authors.initials: K
authors.lastname: Sappayatosok
authors.forename: Somchai
authors.initials: S
authors.lastname: Yodsanga
authors.forename: Somporn
authors.initials: S
authors.lastname: Swasdison
authors.forename: Ann F
authors.initials: AF
authors.lastname: Chambers
authors.forename: Craig A
authors.initials: CA
authors.lastname: Elmets
authors.forename: Kang-Jey
authors.initials: KJ
authors.lastname: Ho
mesh_terms: D002280:Basal Cell Carcinoma / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007642:Keratosis / Q000378:metabolism; D053495:Osteopontin / Q000096:biosynthesis*; D010787:Photosensitivity Disorders / Q000378:metabolism; D011230:Precancerous Conditions / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000378:metabolism* / Q000528:radiation effects; D012878:Skin Neoplasms / Q000378:metabolism*; D013472:Sunlight / Q000009:adverse effects
chemical_list: D053495:Osteopontin