Osteopontin expression in normal skin and non-melanoma skin tumors.
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.
Chang
Pi-Ling
PL
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
Harkins
Louie
L
Hsieh
Yu-Hua
YH
Hicks
Patricia
P
Sappayatosok
Kraisorn
K
Yodsanga
Somchai
S
Swasdison
Somporn
S
Chambers
Ann F
AF
Elmets
Craig A
CA
Ho
Kang-Jey
KJ
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
D053495:Osteopontin