Influence of Immunotherapy (IL2 + LAK + Inhibition of Prostaglandin Synthesis) on Peripheral Blood Immune Parameters and in vitro Cytokine Production in Metastatic Renal Cell Carcinoma

Abstract

Previous results on the peripheral blood immune status of renal cell carcinoma had indicated immunosuppression in metastatic disease, possibly mediated by prostaglandin E₂ (PGE₂). In the present study the immunologic effects of inhibition of PG synthesis by piroxicam in combination with interleukin 2 (IL 2) + lymphokine-activated killer (LAK) cell therapy were tested by immunomonitoring. In additon to peripheral blood parameters (lymphocyte subpopulations, neopterin, β₂-microglobulin, TNF, IL 1, IFNγ) we recorded in vitro cellular activity by incubating the patients’ peripheral blood mononuclear cells (PBMC) in media containing fetal calf serum (FCS) or autologous serum, and either IL 2 or buffer. After 24 h of incubation we measured PGE₂ and cytokine levels in supernatants. Systemic application of IL 2 induced in vivo lymphocyte proliferation and clearly influenced the serum levels of neopterin, β₂-microglobulin and TNF. There was minor affection of IFNγ and none of IL 1. PBMC in vitro produced high amounts of PGE₂, IL 1 and TNF pretherapeutically, during therapy in vitro synthesis of these parameters decreased. Consistent production of IFNγ was detected in supernatants only when FCS and IL 2 were added to the medium. Lack of affection of IFNγ production in the autologous system during therapy indicated impaired cellular activity, which could neither be improved by therapy of the patient using IL 2 nor by adding IL 2 to the culture medium. Immunosuppression seems to interfere in a complex way with immunotherapy. Therapeutical influence of immunosuppression based on the results of immunomonitoring, however, seems to be a promising strategy for improving the still limited clinical results of immunotherapy.

Cyclooxygenase-2 as a Potential Target in the Prevention and Treatment of Genitourinary Tumors: A Review

“…64,65 Favorable responses to current immunotherapy have been observed in patients in whom therapy resulted in decreased PG levels, while conversely those with tumor progression and resistance to therapy have had persistently elevated PG. 66,67 It has also been shown that inhibitors of PG biosynthesis may enhance the therapeutic response. Because of this putative role of PGs in renal cell carcinoma progression and treatment response, and because PGs are directly derived from the COX-2 catalyzed metabolism of arachidonic acid, COX-2 inhibitors may potentially function to decrease PG levels and may have antineoplastic effects in renal tumors.…”