Expression of minichromosome maintenance 5 protein in proliferative and malignant skin diseases.
BACKGROUND
The entire minichromosome maintenance (MCM) family (MCM2-7) play roles in the initiation and elongation of DNA replication. Many studies have demonstrated that MCM proteins may be better indicators of a wide variety of proliferative or cancer cells in malignant tissues.


OBJECTIVE
To characterize the pattern and frequency of MCM5 expression in proliferative and malignant skin diseases in comparison with those of proliferating cell nuclear antigen (PCNA).


METHODS
Twelve normal skin specimens, 12 specimens of psoriasis, 21 specimens of bowenoid papulosis (BP), 16 specimens of Bowen's disease (BD), 38 specimens of skin squamous cell carcinoma (SCC), and 11 specimens of basal cell carcinoma (BCC) were subjected to immunohistochemical staining for MCM5 and PCNA. Results MCM5 protein was expressed in the lower layers of epidermis in psoriasis, while MCM5 protein were present throughout the tumor cells in BP, BD, and moderately/poorly differentiated SCC. MCM5 protein was preferentially expressed in the periphery of well-differentiated SCC or bigger nests of BCC, although some small nests of BCC seemingly showed diffuse staining patterns. The percentages of MCM5-positive cells were 15.7% in normal skin, 21.8% in psoriasis, 75.9% in BP, 83.8% in BD, 63.5% in well-differentiated SCC, 77.5% in moderately differentiated SCC, 79.8% in poorly differentiated SCC, and 21.2% in BCC in average. Well-differentiated SCC showed a significantly lower percentage of positive cells than did moderately differentiated SCC or poorly differentiated SCC. MCM5 staining basically show a similar staining pattern to that of PCNA, but more cells tended to be stained with MCM5 than with PCNA.


CONCLUSIONS
Our results demonstrate pattern and frequency of MCM5 expression in various skin diseases and suggest that MCM5 may be a useful marker to detect cell proliferation in skin tissue sections.
Liu
Houjun
H
Department of Dermatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Takeuchi
Satoshi
S
Moroi
Yoichi
Y
Lin
Nengxing
N
Urabe
Kazunori
K
Kokuba
Hisashi
H
Imafuku
Shinichi
S
Dainichi
Teruki
T
Uchi
Hiroshi
H
Furue
Masutaka
M
Tu
Yating
Y
D001913:Bowen's Disease / Q000378:metabolism; D002280:Basal Cell Carcinoma / Q000737:chemistry; D002294:Carcinoma, Squamous Cell / Q000737:chemistry; D018797:Cell Cycle Proteins / Q000032:analysis*; D002467:Cell Nucleus / Q000737:chemistry; D004817:Epidermis / Q000737:chemistry / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D011565:Psoriasis / Q000378:metabolism; D012867:Skin / Q000737:chemistry / Q000648:ultrastructure; D012871:Skin Diseases / Q000378:metabolism*; D012878:Skin Neoplasms / Q000737:chemistry*
D018797:Cell Cycle Proteins; C489423:MCM5 protein, human; D018809:Proliferating Cell Nuclear Antigen