Possible regulation of soluble icam‐1 levels by interleukin‐1 in a sub‐set of breast cysts

Abstract
There are 2 main groups of breast cysts characterized by their intracystic sodium‐to‐potassium ratios. Women who have intracystic Na/K < 3 may have a higher risk of developing breast cancer than those who have intracystic Na/K > 3. The cell adhesion molecule, ICAM‐1, has been shown to be inducible by interleukin‐1 (IL‐1). Furthermore, ICAM‐1 may be involved in the progression of metastasis in certain malignancies. The aim of this study was to measure intracystic soluble ICAM‐1 (sICAMu‐l) and IL‐1 α/β levels and to assess the relationships between these substances. Wide‐ranging concentrations of sICAM‐1, IL‐1α and IL‐1β were found in breast‐cyst fluid. The high‐electrolyte‐ratio group had intracystic levels of sICAM‐1 and IL‐1β which were significantly higher than those of the low‐electrolyte‐ratio group. No significant difference was found between IL‐1α concentrations in the 2 groups of breast cysts. Strong positive correlations were found between sICAM‐1 and IL‐1α, sICAM‐1 and IL‐1β, and IL‐1α and IL‐1β. The significance of the higher concentrations of sICAM‐1 in the high‐electrolyte‐ratio group remains to be determined, but the results of this study suggest that sICAM‐1 levels in the high‐electrolyte‐ratio group may be regulated in part by IL‐1α and IL‐1β.