Suppression of natural killer cell function and production of soluble ICAM-1: endometrial stroma versus melanoma

PROBLEM: It has been suggested that specific mechanisms commonly used by different cellular systems to evade immunologic recognition are involved in the development of endometriosis. To gain insight into this aspect, we looked at the relationship between two of these mechanisms in endometrial stroma and the melanoma system for which the ability to create an environment of immune privilege has been well established. METHOD OF STUDY: Media conditioned by endometrial stromal cultures and malignant melanoma A375 were examined to test their effects on peripheral blood mononuclear cell-mediated cytotoxicity directed against K562 target. Moreover, these media were tested for the concentration of the soluble form of intercellular adhesion molecule-1 (sICAM-1), which has been suggested as a marker for spreading potential. RESULTS: Media conditioned by endometrial stromal cultures exerted a significant suppressive effect on cell cytotoxicity when compared with those derived from malignant melanoma Moreover, the constitutive release of sICAM-1 was significantly higher in supernatants from endometrial stromal than in melanoma cells. CONCLUSIONS: These results indicate that two specific properties suggested to be involved in the ability of tumor cells to evade the immune system are more pronounced in the endometrium than in a malignant melanoma. Since the properties evaluated have been previously demonstrated to be even more notable in endometrial samples derived from endometriosis patients, a role of these mechanisms in the development of the disease may be hypothesized.