Measurement of the soluble membrane receptors for tumor necrosis factor and lymphotoxin in the sera of patients with gynecologic malignancy.

The shed portion of the 55 and 75 kDa membrane receptors for tumor necrosis factor (TNF) and lymphotoxin (LT) have been described in the serum of patients with cancer. This study was designed to determine whether serum levels of the 55 and 75 kDa soluble TNF/LT receptors (sTNFr) had clinical significance in patients with gynecologic malignancies. Serum samples from 79 patients with ovarian, endometrial, or cervical cancer were assayed for CA 125 levels by RIA and the 55 and 75 kDa sTNFr levels by ELISA. Receptor and CA 125 levels were also analyzed with respect to disease status and response to treatment in banked serum samples from 14 patients with epithelial ovarian cancer who had been followed clinically for 1-3 years. Patients resulted were compared to serum samples tested from normal donors. We found that serum levels of both sTNFr's were elevated in the 79 patients with various gynecologic malignancies [55 kDa of 3.07 +/- 3.79 ng/ml (P < 0.02) and 75 kDa of 2.93 +/- 1.27 ng/ml (P < 0.001)] compared to 16 normal controls (55 kDa of 0.65 +/- 0.22 ng/ml and 75 kDa of 1.62 +/- 0.37 ng/ml). Serum levels of 55 and 75 kDa TNF/LT receptors were a more sensitive indicator of active cancer and had greater predictive value for detecting tumor in patients with ovarian cancer than CA 125. The sTNFr's were also more sensitive than CA 125 in detecting persistent or recurrent tumor and measuring response to therapy. These preliminary results suggest that measurement of serum levels of 55 and 75 kDa sTNFr's, even though not tumor specific, may be a uniquely new method for identifying and monitoring patients with gynecologic malignancy.

Blocking factors (soluble membrane receptors) for tumor necrosis factor and lymphotoxin detected in ascites and released in short-term cultures obtained from ascites and solid tumors in women with gynecologic malignancy.

Studies were conducted to identify and establish the cell and tissue source of blocking factors (BF), materials that inhibit the bioactivity of human TNF and LT in vitro. Ascites and samples of solid tumors were collected from women with various gynecologic malignancies. Supernatants were collected from cultures of tumor and ascites cells after 24, 48, and 72 h. Cell-free ascites (CFA) and culture supernatants were tested for their ability to block human recombinant TNF and LT-induced lysis of L929 cells in vitro. Levels of soluble forms of the 55- and 75-kDa TNF/LT receptors were measured by ELISA assay in the same samples. CFA and culture supernatants contained TNF/LT blocking factors and high levels of one or both soluble 55- and 75-kDa TNF/LT membrane receptors. Levels of BF bioactivity and receptors appeared rapidly, peaked at 24 h, and declined thereafter. Soluble TNF/LT receptors may be the active BF in these samples, and tumor tissues and ascitic cells may be a source of these receptors in the ascites fluid of these patients.

Trafficking of syngeneic murine lymphokine activated killer T cells following intraperitoneal administration in normal and tumor bearing mice.

Nongenetically restricted T cells may be important host effector cells in women with ovarian cancer receiving intraperitoneal (ip) IL-2 therapy. We developed an in vitro technique to produce murine lymphokine-activated killer T cells. Murine splenocytes were cultured in the presence of 1000 U/ml IL-2 for 10 to 15 days. Phenotypical analysis showed 95% of total cells to express the pan T phenotype Thy 1.2 and no NK cell phenotypes by Day 7 in culture. These cells were labeled with 51Cr and their trafficking pattern after ip administration into normal and M5067 tumor bearing mice was examined. Various organs and tissues were collected at different timepoints and monitored for radioactivity. Within 4 hr., about 60% of the counts were associated with the bowel, peritoneum, and omentum of both normal and tumor bearing mice. About 15% of counts were associated with the blood, lung, kidney, spleen, and liver of both normal and tumor bearing mice.

Immunotherapy of ovarian cancer. II. In vitro generation and characterization of lymphokine-activated killer T cells from the peripheral blood of recurrent ovarian cancer patients.

We examined the in vitro sensitivity of continuous ovarian cancer cells to lymphokine-activated killer T cells (T-LAK) alone or in combination with cytokines. Lymphocyte viability in T-LAK cultures generated from normal donors and ovarian cancer patients declined in the first 2 to 4 days; however, the remaining cells in these cultures maintained a constant rate of proliferation for long periods in vitro. These cells became 90-95% CD3+ TCR+ -alpha/beta T-cells after 7-10 days in culture. The T-LAK cells from normal donors and cancer patients expressed an equal ability to induce lysis of a panel of human target cells (NK-sensitive K562, NK-insensitive RAJI, and two human ovarian tumor lines, SKOV-3 and OVCAR-3), demonstrating that they are nongenetically restricted killers. Preincubation of either the effector or target cells with tumor necrosis factor or interferon-gamma or addition of these cytokines directly to cytolytic assays did not alter the degree of cell lysis in vitro. This is a method for generating large numbers of autologous, cytolytically active T-LAK cells from the blood of ovarian cancer patients that could be employed in adoptive intraperitoneal immunotherapy.

Growth of the endometrial adenocarcinoma cell line AN3 CA is modulated by tumor necrosis factor and its receptor is up-regulated by estrogen in vitro.

We demonstrate that tumor necrosis factor (TNF) has a biphasic effect on the growth of the human endometrial adenocarcinoma cell line AN3 CA in vitro. Low levels (0.2-5 pg/ml) of TNF were moderately growth stimulatory (up to 20% enhancement), while levels over 100 pg were growth inhibitory (up to 45% inhibition). Northern blot analysis showed expression of the 75-kilodalton (kDa) TNF receptor mRNA, but no expression of the 55-kDa TNF receptor mRNA or TNF mRNA. The growth of these cells was not directly affected by physiological concentrations (10(-7)-10(-9) M) of 17 beta-estradiol (E2). However, [125I]TNF binding studies and Scatchard analysis showed that 18-h coculture with 10(-8) M E2 increased the number of TNF receptors expressed on these cells 3-fold. Quantitative mRNA analysis confirmed that 75-kDa TNF receptor mRNA expression increased within 4 h of incubation with E2. These observations suggest an interaction between the endocrine and the immune systems, with an important implication for the homeostasis of endometrial tissues.

Identification of tumor necrosis factor and lymphotoxin blocking factor(s) in the ascites of patients with advanced and recurrent ovarian cancer.

Ascites obtained from human ovarian cancer patients contains material(s) that inhibit the cytolytic activity of tumor necrosis factor (TNF) and lymphotoxin (LT) in vitro. These inhibitor(s) are found in ascites from ovarian cancer patients and are detected in very low amounts in the ascites from patients with nonmalignant hepatic disease. These ascites TNF/LT blocking factors are heat sensitive and heterogeneous with respect to molecular weight. Kinetic studies indicate these factors inhibited cytolysis at the stage of TNF/LT interaction with membrane receptors on L929 cells. Because TNF and LT are key cytokines in host cell-mediated antitumor mechanisms, factor(s) that inhibit these cytokines could have a profound effect on the tumor host interaction and their presence in the ascitic fluid, should be considered before designing clinical trials that employ intraperitoneal administration of TNF or LT for immunotherapy of ovarian cancer.

Enhancement of lymphokine-activated T killer cell tumor necrosis factor receptor mRNA transcription, tumor necrosis factor receptor membrane expression, and tumor necrosis factor/lymphotoxin release by IL-1 beta, IL-4, and IL-6 in vitro.

Co-culture with IL-2 can induce human T lymphocytes to proliferate and become nongenetically restricted, lymphokine-activated killer (LAK) cells in vitro. Our studies were conducted with long term cultured, human T-LAK cells from peripheral blood, which are 95 to 99% CD3+. We found that proliferating 7 to 10-day human T-LAK cells express TNFR, by using a 125I-TNF binding assay. Additional treatment of these cells with the cytokines IL-1 beta, IL-4, or IL-6 rapidly up-regulated 55-kDa TNFR mRNA transcription and doubled TNFR membrane expression. Further studies revealed that these cytokines also increased the release of TNF and lymphotoxin (LT). Antibody neutralization studies indicated that IL-1 induces release of both TNF and LT; however, IL-4 and IL-6 induce primarily LT release. These results further support the concept that these cytokines are involved in the regulation of TNF/LT release, TNFR synthesis, and TNFR membrane expression. It is apparent that cytokines and their membrane receptors are involved in the autocrine/paracrine control of T cell proliferation, differentiation, and expression of functional activity after IL-2 stimulation in vitro.

The presence of antibodies to lymphotoxin and tumor necrosis factor in normal serum.

Lymphotoxin (LT) and tumor necrosis factor (TNF) are cytokines that probably play a role in several autoimmune diseases. In this report, we describe the detection, in normal nonimmune serum, of naturally occurring antibodies that bind to recombinant human LT and TNF. The naturally occurring antibodies that bind to LT and TNF could explain why normal immunoglobulin is effective therapy in idiopathic thrombocytopenic purpura and Kawasaki syndrome.