Possible regulation of soluble ICAM-1 levels by interleukin-1 in a sub-set of breast cysts.

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-I, has been shown to be inducible by interleukin-I (IL-I). Furthermore, ICAM-I may be involved in the progression of metastasis in certain malignancies. The aim of this study was to measure intracystic soluble ICAM-I (sICAM-I) and IL-I alpha/beta levels and to assess the relationships between these substances. Wide-ranging concentrations of sICAM-I, IL-I alpha and IL-I beta were found in breast-cyst fluid. The high-electrolyte-ratio group had intracystic levels of sICAM-I and IL-I beta which were significantly higher than those of the low-electrolyte-ratio group. No significant difference was found between IL-I alpha concentrations in the 2 groups of breast cysts. Strong positive correlations were found between sICAM-I and IL-I alpha, sICAM-I and IL-I beta, and IL-I alpha and IL-I beta. The significance of the higher concentrations of sICAM-I in the high-electrolyte-ratio group remains to be determined, but the results of this study suggest that sICAM-I levels in the high-electrolyte-ratio group may be regulated in part by IL-I alpha and IL-I beta.