E. Poggio

Natural killer-mediated cytotoxicity in patients with laryngeal carcinoma

Natural killer (NK)-mediated cytotoxicity against the K562 cell line was evaluated in normal subjects and in patients with laryngeal cancer. Results showed reduced lymphocyte cytotoxicity in patients with neoplastic disease and further reduction in NK activity following postoperative radiation therapy. The authors discuss the possibility of using this test in the immunological monitoring of patients with laryngeal carcinoma.

Production of leukocyte migration inhibition factor by lymphocytes of larynx cancer patients stimulated by laryngeal carcinoma solubilized membrane antigens.

The production of leukocyte migration inhibition factor (LIF) from lymphocytes after stimulation with 3 M KCl soluble tumor and normal mucosa extracts was investigated in 30 patients with laryngeal carcinoma at different development stages and in 30 normal donors. The experiments were performed in heterologous and autologous systems. In heterologous systems 3 M KCl tumor extracts induced LIF production by heterologous lymphocytes from patients in 91 % of the cases, and normal mucosa extracts induced LIF production by heterologous lymphocytes from patients in 73 % of the cases and from normal donors in 90 % of the cases. In autologous systems 3 M KCl tumor extracts induced LIF production by autologous lymphocytes from the same patients in 65 % of the cases, whereas the normal laryngeal mucosa extracts induced LIF production by the same autologous lymphocytes in the 6 % of the cases. The high positivity percentage of the test in heterologous systems could be related to differences in the major histocompatibility complex. The 65 % test positivity in autologous systems using tumor extracts could be related to the presence of tumor associated antigens.

Specific lymphokine responses in cervical nodes of patients with laryngeal cancer

The role of lymphokines in modulating the immune response in patients suffering from neoplastic disease is still controversial. Recent studies indicate that in patients with head and neck cancer, a decrease in LIF (leukocyte migration inhibiting factor) production is usually present in advanced disease. In this study, the authors investigate:

Specific LIF production in laryngeal cancer patients: Evidence of suppressor activity exerted by adherent cells

The specific tumor-induced LIF production in 30 laryngeal cancer patients has been investigated before and after the removal of adherent cells to evaluate the existence of a suppressor activity. LIF production, after challenging lymphocytes with 3 M KCl autologous tumor extracts, was significant in 16 patients and showed a further significant increase after removal of adherent cells. A conversion to significance when the adherent cells were removed was shown in 6 patients, with no previous significant LIF production. These data suggest the existence of a suppressor activity exerted by adherent cells on LIF production in laryngeal cancer patients.

Evaluation of blocking mechanisms against immunological responses in patients with laryngeal carcinoma

The specific tumor‐induced leukocyte inhibition factor (LIF) production in laryngeal cancer patients has been investigated before and after the removal of adherent cells in order to evaluate the existence of a suppressor activity; 20 patients served as subject. The LIF production, after challenging the lymphocytes with 3MKC1 autologous tumor extracts, was significant in 12 patients and showed a further significant increase after the removal of adherent cells. In 3 patients with no previous significant LIF production, there was a conversion to significance when the adherent cells were removed. The other patients did not show any significant variation. These data seem to suggest the existence of a suppressor activity exerted by adherent cells in laryngeal cancer patients on LIF production.