Antitumor effect of recombinant human interleukin-1 beta alone and in combination with natural human tumor necrosis factor-alpha

Serum concentrations of cytokines and lung cancer survival in African Americans and Caucasians

Accumulating evidence suggests a role for inflammation in the development and progression of cancer. Our group recently identified a cytokine gene signature in lung tissue associated with lung cancer prognosis. Therefore, we hypothesized that concentrations of circulating cytokines in serum may be associated with lung cancer survival. Ten serum cytokines, namely, interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, granulocyte macrophage colony-stimulating factor, interferon (IFN)-gamma, and tumor necrosis factor-alpha, were assessed in 353 non-small cell lung cancer cases from a case-control study of lung cancer in the greater Baltimore, Maryland area. Cytokines were measured using an ultrasensitive electrochemiluminescence immunoassay. IL-6 serum concentrations (>or=4.0 pg/mL) were associated with significantly poorer survival in both African Americans [hazard ratio (HR), 2.71; 95% confidence interval (CI), 1.26-5.80] and Caucasians (HR, 1.71; 95% CI, 1.22-2.40). IL-10 (HR, 2.62; 95% CI, 1.33-5.15) and IL-12 (HR, 1.98; 95% CI, 1.14-3.44) were associated with lung cancer survival only in African Americans. Some evidence for an association of tumor necrosis factor-alpha levels with survival in Caucasians was observed, although these results were not significant. These hypothesis-generating findings indicate that selected serum cytokine concentrations are associated with lung cancer survival, and indicate that further research is warranted to better understand the mechanistic underpinnings of these associations.

Tumour necrosis factor-alpha and transforming growth factor-beta are significantly associated with better prognosis in non-small cell lung carcinoma: putative relation with BCL-2-mediated neovascularization

Recent in vivo and in vitro studies have demonstrated a wide spectrum of biologic activities of cytokines in the pathogenesis and progression of malignancy. Tumour necrosis factor alpha (TNF-alpha) and transforming growth factor beta (TGF-beta) have emerged as two of the many host-derived mediators that seem to interfere with both antiproliferative and tumorigenic effects in malignant tumours including lung cancer. However, their association with tumour prognosis or prognostic factors has not yet been completely clarified. In this study, we assessed TNF-alpha and TGF-beta mRNA expression by RT-PCR technique in 61 NSCLC samples, demonstrating the presence of TNF-alpha and TGF-beta mRNA in 55.74% and 45.9% of cases, respectively. We also evaluated the expression of the two distinct transmembrane TNF receptors. TNFR-I and TNFR-II, with a PCR-positive signal in 70.49% and 65.57% of cases, respectively. In 49 of the 61 cases, we evaluated the prognostic impact of the two growth-inhibiting factors using the Kaplan-Meier analysis. In the univariate analysis patients without nodal metastatic involvement (P = 0.02), less advanced tumour stage (P = 0.02) or TNF-alpha and TGF-beta positive cancers (P = 0.01 and P = 0.03) showed a favourable prognosis in terms of overall survival. Since our previous studies demonstrated a significant association between NSCLC behaviour, neoangiogenesis and bcl-2 expression, we investigated the putative relation between TNF-alpha and TGF-beta on the one hand, and vascular count (as a measure of tumour angiogenesis) and bcl-2 protein expression, on the other hand. Our results showed a significant direct association between TNF-alpha and bcl-2 (P = 0.05) and an inverse association between TNF-alpha and microvessel count (P = 0.03). Moreover, as previously demonstrated, we observed a significant inverse correlation between bcl-2 protein expression and vascular count (P = 0.05), suggesting that the favourable effect of TNF-alpha on clinical outcome may be related to a bcl-2-mediated low neovascular development.

Cytokines in animal models of cancer

Cytokines are a complex family of mediators that play a wide role in development, immunity, inflammation and tissue repair. Their use in therapy is still in its infancy and animal models have a key role to play in optimizing doses and schedules. Whilst xenogeneic and syngeneic transplantable systems have traditionally been used to look at the effects of cytokines in tumour models, oncogene transgenic mice prone to develop cancer, may now have a role to play. Moreover, gene therapy has allowed the investigation of ectopically expressed high and continuous levels of cytokines. We will attempt to review the literature on the effect of cytokines and their combinations in these models of cancer.

The synergistic antitumor effect of recombinant interleukin-1 and low-dose of cyclophosphamide in tumor-bearing mice

Intraperitoneal (i.p.) treatment of MOPC104E ascitic tumor-bearing BALB/c mice with interleukin-1 (IL-1) followed by a low dose of cyclophosphamide (CPA) resulted in synergistic prolongation of their survival time. This antitumor effect was abolished when administration of CPA preceded that of IL-1. The combined i.p. therapy also eradicated subcutaneous (s.c.) tumors, indicating a systemically operating antitumor mechanism. In Winn assay, splenocytes from MOPC104E-bearing mice treated with the combined therapy completely suppressed the growth of MOPC104E cells, but not that of another syngeneic tumor cell line, RL female-8 cells. This tumor-neutralizing activity was completely abrogated by treatment with anti-asialo-GM1 or anti-Thy1.2 and complement, and reduced by treatment with anti-Lyt2.2 and complement. Treatment of splenocytes with 1-leucine methyl ester (Leu0Me), which depletes natural killer (NK) cells and macrophages in vitro, did not affect the neutralizing activity.

Tumor necrosis factor activities and cancer therapy--a perspective

Tumor necrosis factor (TNF) is a multifunctional cytokine which has excited and fascinated numerous investigators and commercial entities due to its promise as a therapeutic agent against cancer and as a target for drugs treating septic shock. TNF is a protein having cytotoxic, cytostatic, immunomodulatory as well as several other activities and is also involved in septic shock. This review covers the structure of TNF and its receptors, various in vitro activities and in vivo activities based on studies in animal model systems. The role of TNF as an anticancer therapeutic agent, based on various phase I and phase II clinical studies, has also been considered. The review concludes with several considerations for increasing the therapeutic utility of TNF in terms of targeting, toxicity and half-life.