Estrogen Receptor and Aromatase in Squamous Cell Carcinoma of the Skin
K Abe, M Mori, Y Miki, T Inoue, K Ono, Y Shibahara, J Akahira, H Sasano. Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan; Biological Science Laboratories, Kao Corporation, Tochigi, Japan
Background: Estrogen has been known to be involved in development and/or progression of tumor cells arising in several organs including breast, endometrium, ovary, and others. Human skin is also considered the target organs of estrogens, which play some roles in the age-related dermal changes. In primary squamous cell carcinoma (SCC) of the skin, past history of burn and irradiation have been in general considered one of the important local carcinogenetic factors. In normal skin, fibroblasts in dermis have been demonstrated to express aromatase, one of the estrogen-producing enzymes, has also been proposed based on these findings but their details remain unknown. These injuries to skin above may also be considered to result in the disruption of estrogen-related physiological functions of the skin, which cause tumor. In this study, we therefore examined whether estrogen receptor (ER) α, ERβ and aromatase are expressed in SCC of the skin or not.
Design: Forty-eight cases (male: female 33:15, age range 44-99 yo.) with primary SCC of the skin were retrieved for imuunohistochemical study of ERα, ERβ, aromatase and Ki67. The specimens had been all fixed in 10% formaldehyde solution and embedded in paraffin. Serial tissue sections were used for hematoxylin-eosin staining and immunohistochemistry, performed by LSAB method. Nuclear immunoreactivity for ERα and ERβ was evaluated in 500 cancer cells, and the percentage of positive cells was subsequently obtained. Cytoplasmic immunoreactivity for armoatase with more than 10% of carcinoma cells was defined as “positive “. Ki67 labeling index was also obtained by counting 500 carcinoma cells. The statistical calculations, STATA version 7 (College Station, Texas) was used. P value under 0.05 was considered significant. Research protocols for this study were approved by Ethics Committee at University School of Medicine.
Results: ERα, ERβ and aromatase were positive in 93.75% (45/48 cases), 97.9% (47/48 cases) and 58.3% (28/48 cases), respectively. The positive rate of ERα among aromatase-positive cases was significantly higher among aromatse-negative cases (p<0.05, Mann-Whitney test). The age of aromatase-positive cases was significantly younger than aromatase-negative ones (p<0.05, Mann-Whitney test).
Conclusions: These results suggest that the combined expression of ERα and aromatase could be related to carcinogenesis and/or progression of SCC of human skin.
Wednesday, March 24, 2010 1:00 PM
Poster Session VI # 93, Wednesday Afternoon