Synergistic antitumour effect of TNF-SAM2 with melphalan and doxorubicin in isolated limb perfusion in rats.

An isolated limb perfusion model (ILP) using soft tissue sarcoma bearing rats (BN175) was used to study antitumour activity of a tumour necrosis factor alpha mutant (TNF-SAM2) in combination with melphalan and doxorubicin. Progressive disease was demonstrated after ILP without agents (sham) or with 50 micrograms TNF-SAM2. ILP with 40 micrograms melphalan or 400 micrograms doxorubicin resulted in no change of tumour volume or progressive disease five days after perfusion. Partial and complete response rates were demonstrated in 76% of rats when the combination of TNF-SAM2 and melphalan was used. TNF-SAM2 in combination with doxorubicin was synergistic as well with a 70% response rate. Histopathologically these responses consisted of hemorrhagic necrosis of the coagulative type. 2 In conclusion, TNF-SAM2 has similar antitumour activity in combination with melphalan or doxorubicin as rHuTNF in sarcoma-bearing rats and is eligible to be tested in clinical ILP or organ perfusion settings because of its potential decreased toxicity.

Pharmacokinetics of isolated hepatic perfusion with high dose tumor necrosis factor in rat model.

BACKGROUND: Although the application of an isolation procedure with tumor necrosis factor (TNF) to the liver is quite attractive, an animal model is not yet available to evaluate antitumor effects by TNF in isolated hepatic perfusion (IHP). To establish the rat model in IHP, the pharmacokinetics of TNF, both in a perfusate and in a systemic circuit should be examined. METHODS: All rats underwent IHP with TNF. After a 10 min perfusion, a washout procedure was performed for 5 min, after which isolation was terminated. Throughout the procedure and afterward, blood samples were obtained from the systemic blood and concentrations of TNF were assayed by L-929 cytotoxicity. RESULTS: After the administration of 240 micrograms of TNF in the circuit, TNF reached a plateau at about 12.7 micrograms/ml of perfusion fluid, lasting until the end of IHP. As a result of the washout procedure, regional TNF concentrations declined from 12.7 micrograms/ml to 1.5 micrograms/ml. At the beginning of the IHP, all rats exhibited no detectable level of TNF activity in the systemic circulation (< 100 pg/ml). With time, TNF plasma levels quickly increased to reach a plateau of about 0.2 microgram/ml at 15 min. Systemic leakage of TNF is calculated as less than 2% of the total TNF in perfusate during perfusion. CONCLUSION: Rat IHP models with TNF showed that systemic leakage of TNF was higher than that of pig models, although a large enough amount of TNF in perfusate was achieved without death. Rat models might be feasible to evaluate antitumor effect of IHP against liver metastatic tumors.

Reduction of hepatotoxicity of tumor necrosis factor in isolated hepatic perfusion by administration of glucocorticoid as well as lipopolysaccharide.

BACKGROUND: The application of an isolation procedure with tumor necrosis factor (TNF) to the liver is quit attractive, however, one of problems to overcome is reducing the toxicity to the liver caused by high doses of TNF. MATERIALS AND METHODS: Rats underwent isolated hepatic perfusion (IHP) with TNF and pre-treatment of subcutaneous administration of dexamethasone (4 mg/kg) and/or intradermal administration of LPS (50 micrograms/rat). After a 10 min perfusion, a washout procedure was performed for 5 min, after which isolation was terminated. RESULTS: SD or Wister rats and F344 rats tolerated up to 120 mg/rat or 4 micrograms/rat, respectively. Dexamethasone and/or LPS was tolerated at 40 micrograms/rat of TNF in F344 rat and showed a significant reduction of hepatotoxicity, and indicated histologically the suppression of ballooning and of necrosis during and after perfusion by TNF. CONCLUSION: We propose new a protocol for IHP as follows: 1. the intradermal administration of LPS for protection against toxicity of TNF, 2. IHP with TNF-SAM2, a mutain of TNF-alpha, having less toxicity than conventional TNF-alpha, and 3. simultaneous perfusion with chemotherapeutic agents such as 5-fluorouracil (5-FU).

Preservation of metastatic ability of colorectal tumor cells stratified by inducibility of endogenous tumor necrosis factor after orthotopic transplantation in nude mice.

BACKGROUND: Inducibility of endogenous tumor necrosis factor (TNF) by colorectal tumor cells can be regarded as a novel prognostic factor in terms of distant metastasis or local recurrence following curative operation, especially at Duke's stage C. In this study, the metastatic ability of human colorectal tumor cells stratified by inducibility of endogenous TNF was analyzed by orthotopic transplantation in nude mouse. METHODS: Fifty three cases of freshly resected colorectal tumor specimens cut into about 50mg pieces were inoculated into the cecum wall of nude mice. Two to nine months after transplantation, tumor growth on this wall and metastases to the peritoneal wall as well as to the liver were assessed. RESULTS: Of forty one evaluable cases, successful transplantation was observed in twenty nine (70%), and metastases to the peritoneal wall or to the liver was found in thirteen (32%), or eight cases (20%), respectively. In the twenty nine cases with local tumor growth, incidence of the liver metastases in nude mice when tumor specimens from patients with liver metastases (4/8) were used was significantly higher than that from patients without liver metastases (4/21) (P = 0.096). Inducibility of endogenous TNF was separately analyzed in fourteen of the evaluable twenty nine cases. Seven cases belonged to the high group and seven to the low group in terms of the amount of endogenous TNF secreted by tumor cells. Incidence of metastases in mice was 1/7 in the high group and 6/7 in the low group, and there was a statistically significant difference between liver metastases in mice and inducibility of endogenous TNF by colorectal tumor cells (p = 0.0057). CONCLUSION: From these results, it is strongly suggested that inducibility of endogenous TNF by colorectal tumor cells can affect a patient's prognosis since it regulates metastatic ability to the liver.

Endogenous TNF inducibility and prognosis of colorectal cancer.

BACKGROUND: We have demonstrated that the inducibility of endogenous TNF (en-TNF) by colorectal tumor cells is a factor in predicting a patient prognosis. The prognoses of colorectal tumor patients with the K-ras gene mutations in their tumors were poorer to those of patients with the wild type gene. Therefore, we analyzed the possible relationship between the inducibility of en-TNF by colorectal tumor cells during the follow-up of patients with K-ras mutations. MATERIALS AND PATIENTS: In 62 of 154 Dukes Stage C patients who received curative operation from June 1988 to June 1997, the prognoses in terms of the tumor-free rate and survival rate were compared with the inducibility of en-TNF by colorectal tumor cells, which were classified into three groups: grade 1: > or = 500 pg/ml, grade 2: 100-500 pg/ml, and grade 3: < 100 pg/ml. Regardless of the Dukes Stage of the patients, the K-ras gene was analyzed in 21 whose colorectal tumor cells were classified as grade 1: 8, grade 2: 4, and grade 3: 9. RESULTS: The tumor-free rate of the patients with grade 1 was significantly higher than that of the patients with grade 3, and the survival period of the patients with grades 1 and 2 was significantly longer than that of the patients with grade 3. Possible mutations disorder of K-ras were observed in 37.5% (grade 1), 50.0% (grade 2), and 88.9% (grade 3) of cases, respectively. CONCLUSION: The prognostic value of the inducibility of en-TNF by colorectal tumor cells from colorectal cancer patients who received curative operation at Dukes Stage C was confirmed. It is suggested that K-ras mutation may affect patient prognosis through modulation of the quality and/or quantity of cytokines such as TNF produced by tumor cells.

A long-term survivor case of malignant mesothelioma treated by recombinant tumor necrosis factor-SAM2 (TNF-alpha mutein) and 5-fluorouracil (5-FU): a new therapeutic approach based on host-tumor relationship.

BACKGROUND: The prognosis of mesothelioma is very poor, and there is no established method to suppress tumor growth. Immunological approaches have recently been thought to be effective for mesothelioma and several studies using cytokines have been performed. We used a novel recombinant tumor necrosis factor-alpha (rTNF-alpha) we called rTNF-SAM2, in the treatment of a patient with this disease. PATIENT AND METHOD: A 48-year old male patient with ascites was diagnosed with malignant mesothelioma by cytological examination. TNF-SAM2 in an amount of 264 to 576 micrograms (1 to 2.2 x 10(6) U) was injected via a catheter several times. Five hundred mg of 5 fluorouracil (5-FU) was also given via catheter once a week and 5-FU derivative was given orally every day. RESULTS: No apparent tumor progression was observed for 6 years and 6 months and the patient led a normal life. During the therapy, the malignancy of tumor cells from the ascites changed from class V to class VI. CONCLUSION: TNF based therapy may be promising treatment for the suppression of malignant mesothelioma.