Synthesis, structure and antitumor activity of new benz[d,e]isoquinoline-1,3-diones.

New benz[d,e]isoquinoline-1,3-diones related to mitonafide (CAS 54824-17-8) and amonafide (CAS 69408-81-7) with double substitution on the chromophore and branched side chains have been synthesized and their biological activity determined. Molecular modeling studies of 3a based on X-ray crystallographic data of mitonafide have shown that the aromatic system intercalates between GC steps of DNA. The in vitro cytotoxic test data using CX-1 and LX-1 cells showed higher cytotoxic activities in disubstituted derivatives compared to both lead compounds.

Benzimidazo[1,2-c]quinazolines: a new class of antitumor compounds.

A series of substituted benzimidazo[1,2-c]quinazolines have been synthesized. This class of compound has been designed by structural comparison with other intercalator patterns. The determination of in vitro activities has shown high inhibitory values.

Synthesis of new derivatives of flavone-8-acetic acid.

The synthesis of new flavone-8-acetic acid derivatives is described. It is studied the influence of a dialkylaminomethyl group in the 3-position on the activity. None of the new compounds showed cytostatic activity.

Bis-naphthalimides: a new class of antitumor agents.

A series of bis-intercalators bearing the 1,8-naphthalimide chromophore has been synthesized and in vitro activities determined. Most compounds have higher activities in HT-29 than the leader compounds Mitonafide and Amonafide. One of them (22) was selected for in vivo studies and presents an interesting activity in MX-1 and OVCAR models.

In vivo administration of tumor necrosis factor-alpha is associated with antiviral activity in human peripheral mononuclear cells.

Tumor necrosis factor-alpha (TNF-alpha) has a spectrum of biologic effects and has been shown to exert antiviral effects in fibroblasts in vitro. The in vivo administration of TNF-alpha (40-160 micrograms/m2 intravenously over 2 hr) and its effects on vesicular stomatitis virus (VSV) replication in peripheral blood mononuclear cells (PBMC) from patients with malignancy was investigated. Blood was obtained before, during, and after infusion.

Effect of intraperitoneal recombinant human tumour necrosis factor alpha on malignant ascites.

29 patients with refractory malignant ascites due to metastatic peritoneal spread of adenocarcinomas originating from the ovary, gastrointestinal tract, liver, breast and uterus were treated in a phase I trial of intraperitoneal infusions of recombinant human tumour necrosis factor alpha (rhTNF-alpha). Patients received 40-350 micrograms/m2 rhTNF-alpha intraperitoneally once weekly for 2 months or for a shorter period in case of early resolution of ascites. Systemic side-effects resembled those reported for rhTNF-alpha given intravenously.

Circumvention of multidrug resistance mediated by P-170 glycoprotein using calcium antagonists in primary human renal cell carcinoma.

In experimental cell lines and in some human tumors, calcium antagonists reversed multidrug resistance mediated by P-170 glycoprotein in vitro. So far, clinical trials have not been very rewarding as intrinsic cardiovascular activities of these compounds impeded sufficient dosage. Renal cell carcinomas are considered to be good models for the evaluation of this new therapeutic concept.

[Therapy of ascites with tumor necrosis factor in ovarian cancer].

The biotechnological production of human recombinant tumour necrosis factor (rHuTNF) makes this drug available for clinical application. This endogenous compound exhibits tumouricidal activity and regulatory functions within the immune system. 20 out of 23 (87%) patients with refractory recurrent malignant ascites from ovarian cancer were successfully treated in a phase-I and II-study.

Effects of calcium antagonists in multidrug resistant primary human renal cell carcinomas.

Human renal cell carcinomas display a characteristically high degree of intrinsic chemoresistance to a multitude of chemotherapeutic agents. It was suggested previously, that P-170 glycoprotein contributes to this phenomenon in renal cell carcinoma indicated by elevated MDR-1 gene mRNA levels and by the expression of this specific resistance characteristic. The P-170-related efflux mechanism can be inactivated by certain calcium antagonists.

Monoclonal antibodies to human tumor necrosis factor alpha: in vitro and in vivo application.

Three stable murine hybridoma cell lines, which secrete monoclonal antibodies (mAb) to human tumor necrosis factor alpha (TNF alpha), were established. None of the monoclonal antibodies cross-reacted with lymphotoxin, interleukin 2 (IL 2) or Interferon gamma (IFN gamma). The highly species-specific monoclonal antibody, designated as mAb 195, neutralizes the cytotoxic activity of human and chimpanzee TNF alpha.

[Role of calcium antagonists in the treatment of chemoresistant cancer of the kidney].

In experimental cell lines and in some human tumors, calcium antagonists reversed multidrug resistance in vitro. So far, clinical trials have not been very rewarding as intrinsic cardiovascular activities of these compounds impeded a sufficient dosage. Renal cell carcinomas are considered to be good models for the evaluation of this new therapeutic concept.

Chemosensitivity testing of primary human renal cell carcinoma by a tetrazolium based microculture assay (MTT).

MTT staining procedures have been used in chemosensitivity testing of established cell lines of human and other sources as well as of human leukaemias, but only limited information on its application in primary solid human tumors is presently available. We have evaluated MTT staining in primary human Renal Cell Carcinomas (RCCs), studied various factors interfering with the optimal use, and finally applied it in subsequent chemosensitivity testing. The method depends on the conversion of a water-soluble tetrazolium salt (MTT) to a purple colored formazan precipitate, a reaction effected by enzymes active only in living cells.

Tumour necrosis factor production and natural killer cell activity in peripheral blood during treatment with recombinant tumour necrosis factor.

Tumour necrosis factor (TNF) has been found to be an important immunomodulator. Among other functions TNF activates natural killer (NK) cells and stimulates monocytes/macrophages in an autocrine fashion. TNF production and NK activity in peripheral blood mononuclear cells were determined in a clinical phase I study in which recombinant human (rh) TNF was administered as a continuous infusion weekly for a period of 8 weeks.

Phase I study of recombinant human tumor necrosis factor alpha in advanced malignant disease.

A phase I study with recombinant human tumor necrosis factor alpha (rhuTNF-alpha; Knoll AG, Ludwigshafen, FRG) in patients with advanced malignant disease was undertaken to evaluate drug toxicity (organ specificity, time course, predictability, reversibility, maximal tolerated dose), effectiveness, antigenicity and pharmacokinetics. TNF was administered as a test dose followed by daily i.v.

Phase-I trial of intravenous continuous infusion of tumor necrosis factor in advanced metastatic carcinomas.

Fifteen patients with advanced metastatic adenocarcinomas were treated in a phase-I study with continuous intravenous 24 h infusion of recombinant tumor necrosis factor alpha (TNF-alpha) in order to determine the maximum tolerated dose (MTD) and associated side-effects. Patients received 40-400 micrograms/m2 TNF-alpha once (arm A) or twice (arm B) weekly for a scheduled treatment period of 2 months. The observed systemic side-effects resembled those reported for interferons and included fever, chills, fatigue, headaches, myalgias, thrombocytopenia, prostration, and malaise.

Decrease of natural killer cell activity and monokine production in peripheral blood of patients treated with recombinant tumor necrosis factor.

Tumor necrosis factor (TNF), a protein predominantly produced by activated macrophages/monocytes, is presently available in recombinant, purified form for clinical trials. Intensive studies in many laboratories have shown that besides the tumorcytotoxic effects, TNF acts on a large array of different cells and has potent immunomodulatory activities. In a clinical phase I study, some immunologic functional parameters of blood cells from patients who received 24-hour infusions of recombinant human TNF (rhTNF) were analyzed.

Immune response by biological response modifiers.

Several biological response modifiers (BRMs) were demonstrated to increase myelopoiesis and effector cell responses (M phi and natural killer cell activity) in vivo. The increased myelopoiesis was reflected by an increase in bone marrow cellularity and granulocyte-M phi colony-forming cells (GM-CFU-C). The increase in myelopoiesis appeared to be related to a concomitant increase in colony-stimulated factor (CSF) production and secretion by M phi and bone marrow cells.

Protein deficiency reduces natural antitumor immunity.

Clinical data have shown that neoplastic diseases and/or related therapies frequently result in protein depletion of tumor-bearing patients. Depressions of acquired and specific immunity caused by protein depletion are well known. In an experimental model protein depletion was induced by lack of nutritional protein in otherwise isocaloric conditions in BALB/c and C57BL/6 mice over various time periods (max.

1,25-Dihydroxycholecalciferol-induced differentiation of myelomonocytic leukemic cells unresponsive to colony stimulating factors and phorbol esters.

The murine myelomonocytic leukemia cell line WEHI-3B D+, which differentiates in response to granulocyte colony stimulating factor (G-CSF), can also be induced to differentiate into monocyte-macrophages by phorbol myristate acetate (PMA) treatment, whereas the WEHI-3B D- subline, which is unresponsive to G-CSF and PMA, can be induced to differentiate to granulocytes as well as monocytes by 1,25-dihydroxycholecalciferol [1,25-(OH)2 D3], the biologically active metabolite of vitamin D3. A newly developed variant of the WEHI-3B D+ line, named WEHI-3B D+ G, which was responsive to G-CSF but not to PMA, was also differentiated to granulocytes by 1,25-(OH)2 D3. Although vitamin D3 has been reported to induce macrophage differentiation in responsive tumor cells, this is the first demonstration that 1,25-(OH)2 D3 can induce granulocyte differentiation.

Adjuvant chemoimmunotherapy of cancer: influence of tumor burden and role of functional immune effector cells in mice.

Starting from the observation that success of combined treatment of MBL-2 tumor-bearing mice with the alkylating agent cyclophosphamide (CY; 150 mg/kg) and the immunomodulator maleic anhydride divinyl either copolymer (MVE-2; 25 mg/kg) was dependent upon a 1-3-day interval between treatment with CY and MVE-2, we have further analyzed in vitro and in vivo the relationship between tumor burden and the activity of immune effector cells in an adjuvant chemoimmunotherapy setting with CY and MVE-2. Treatment of MBL-2 tumor-bearing mice with CY (50-200 mg/kg) caused a dose- and time-dependent decrease in the i.p.

Selective killing of human T-lymphotropic virus-I infected leukemic T-cells by monoclonal anti-interleukin 2 receptor antibody-ricin A chain conjugates: potentiation by ammonium chloride and monensin.

Adult T-cell leukemia is a progressive disease produced by infection of mature T-cells with the human T-lymphotropic virus-I (HTLV-I). These retrovirus infected T-cells express large numbers of receptors for interleukin 2 (or T-cell growth factor). Due to the presence of these receptors, these leukemic T-cells can be selectively killed in vitro by monoclonal anti-interleukin 2 receptor antibody covalently linked to the A chain of the plant toxin, ricin (anti-TAC-A), suggesting that such immunotoxins may be useful in the therapy of this disease.

[Protein deficiency, host defense and natural anti-tumor immunity].

Natural immuneffector cells, namely natural killer cells and monocyte/macrophages, have become in recent years an important part of theory and practice of immunotherapy. This is especially the case for therapy of malignant tumors with biological response modifiers (BRMs). Many BRMs increase cytotoxicity against tumor cells and cell numbers of natural immuneffector cells.

In vivo induction of terminal differentiation of malignant myelopoietic progenitor cells by CSF-inducing biological response modifiers.

We have investigated the mechanisms by which colony-stimulating factor (CSF)-inducing biological response modifiers (BRM) may have beneficial effects on tumor-bearing hosts undergoing anti-tumor therapy. First, we have documented that treatment of mice with the chemically defined BRM maleic anhydride divinyl ether copolymer (MVE-2), which induces CSF secretion by macrophages (M phi) and bone marrow cells (BMC), significantly increased growth and differentiation of normal myelopoietic cells and counteracted the myelosuppressive effects of cyclophosphamide (CY). Second, we established that MVE-2 may exert CSF-mediated antitumor effects on certain leukemic tumor cells.