RESISTANCE TO PGE(2) INHIBITION OF PWM-STIMULATED LYMPHOCYTES FROM NEOPLASTIC PATIENTS

PGE(2) treatment of mononuclear cells from patients with different typ es of neoplasias was unable to decrease either the number of plaque-fo rming cells or the expression of CD71 and CD25 in PWM-driven cultures, In contrast, in previous studies, PGE(2) inhibited these parameters i n cultured mononuclear cells from normal volunteers. Surgical treatmen t of cancer patients did not modify the lymphocyte sensitivity to PGE( 2) after 1 week, but at 2 and 6 months after therapeutical treatment, the inhibition values of the parameters studied were almost similar or very similar to those of normal lymphocytes. The reduction of PGE(2) sensitivity in cancer patients was related to the increase of PGE(2) l evels and, probably, to a PGE(2) receptor saturation. A restoration of PGE(2)-induced inhibition some months after therapy could be due to t he decrease in PGE(2) levels and to receptor unsaturation. (C) 1998 Ac ademic Press.