[217] The Role of Adipocytes in Mammary Carcinoma Microenvironment

JY Kim, FA Tavassoli. Pusan National University School of Medicine, Busan, Korea; Yale University School of Medicine, New Haven, CT

Background: Recent studies suggest a role for tumor microenvironment in mammary carcinogenesis. The most numerous cell population surrounding breast cancers, adipocytes are surprisingly the least studied cell in this microenvironment. This study examines the expression of a cell cycle regulator, p53, in adipocytes surrounding various ductal proliferative lesions with or without invasive carcinoma.
Design: 293 cases of ductal intraepithelial neoplasia (DIN) were retrieved from the surgical pathology files of our institution. These included 119 DIN associated with invasive carcinoma: and 174 pure DIN. A representative slide from each case was evaluated for immunoexpression of p53 in the adipose tissue. Results were interpreted as follows; negative (0-10%) and positive (>10%). The expression of p53 was correlated with patients' age and type of proliferation.
Results: The p53 expression increased with increasing patient age with the highest expression among patients aged 81 to 96 years (44%), followed by those 51-80 (29%), 41-50 (25%) and 21-40 (17.5%) years of age. The most extensive adipocyte p53 expression was in cases associated with invasive carcinomas (36%) compared to 15% for those without invasive carcinoma. The p53 expression in the adipocytes did not directly correlate with the grade of DIN.
Conclusions: Adipocytes in breast have multiple functions including elaboration of cell cycle regulators that may influence mammary carcinogenesis. The findings in our study of 1) an increase in adipocyte p53 expression with increasing patient age in parallel to the increasing frequency of breast carcinoma with age and 2) the most extensive p53 expression in association with invasive carcinomas support such a role.
Category: Breast

Monday, March 9, 2009 1:00 PM

Poster Session II # 58, Monday Afternoon