[p55 and p75 subunits of the IL 2 receptor, membrane bound and soluble, in peripheral lymphocytes in patients with solid tumors]

The aim of the investigation was to directly study the IL 2 receptor (IL 2 R) and its subunits, p55 and p75 chains, either membrane-bound or soluble, on peripheral blood mononuclear cells (PBMC) of patients with solid malignancies and, indirectly, the same patients' PBMC ability to produce IL 2. Fifty-eight cancer patients, 29 men and 29 women, were studied: their mean age was 57.3 years, range 35-79. Twenty-two healthy age-sex-matched subjects served as controls. The tumors were the most common and the most representative among human cancers, i.e. breast, lung, head and neck, digestive tract and liver, prostate and gynecologic cancers: they were generally in advanced stages and in 23 cases metastatic. The PBMC proliferative response to PHA, PHA plus IL 2 and IL 2 was evaluated along with the response to PHA in presence of anti-p55, anti-p75 monoclonal antibodies, or both. Moreover, membrane-bound IL 2 R, p55 and p75 chains, on PHA-stimulated PBMC were detected, along with soluble IL 2 R in the serum and in the culture supernatants. The conclusions suggest that in solid malignancies: the membrane-bound IL 2 R s, both p55 and p75 chains, are expressed normally, there is an high serum level of soluble IL 2 R, there is a normal release of soluble IL 2 R in culture, and there is an indirect evidence of a lack of IL 2 production. Therefore, no primary impairment of IL 2 R was found in solid tumors.(ABSTRACT TRUNCATED AT 250 WORDS)