Specific distribution patterns of hCDC47 expression in cutaneous diseases.

hCDC47 is a human member of the MCM family, which has been implicated to be concerned with the regulatory machinery causing DNA to replicate once per cell cycle. In a previous paper, we described hCDC47 expression as being localized in the proliferative component of normal tissues, and showed greater expression in squamous cell skin carcinomas than in seborrheic keratosis. In the present study, we compared its expression in another type of skin tumor and various non-neoplastic cutaneous proliferative diseases. Two patterns of distribution of hCDC47-positive cells were observed. Keratoacanthomas showed a peripheral pattern in which only the cells located the basal cell layers were positive. Psoriasis vulgaris also showed this peripheral type of location, with the cells in the suprabasal layers also occasionally expressing hCDC47. Verruca vulgaris demonstrated a diffuse pattern, with positive epithelial cells distributed throughout the layers. Basal cell carcinomas also showed a similar pattern. The keratoacanthomas showed the highest hCDC47 positive cell rate (43.1%), followed by verruca vulgaris (42.5%), psoriasis vulgaris (23.4%), and basal cell carcinoma (17.3%). Our results suggest participation of hCDC47 in these proliferative disorders involving keratinocytes.