chiniofon and Prostatic-Neoplasms

Prostate cancer is the mostly commonly diagnosed non-skin cancer in males. The culmination of the last 70 years of clinical drug development has documented that androgen ablation plus taxane-based systemic chemotherapy enhances survival, but is not curative, in metastatic prostate cancer. To effect curative therapy, additional drugs must be developed that enhance the response when combined with androgen ablation/taxane therapy.. The history of the discovery and development of tasquinimod as a second-generation oral quinoline-3-carboxamide analogue for prostate cancer will be presented.. The mechanism for such anticancer efficacy is via tasquinimod's ability to inhibit the 'angiogenic switch' within cancer sites required for their continuous lethal growth.. Tasquinimod is a novel inhibitor of tumor angiogenesis that enhances the therapeutic anticancer response when combined with other standard-of-care modalities (radiation, androgen ablation, and/or taxane-based chemotherapies) in experimental animal models, but does not inhibit normal wound healing. It has successfully completed clinical Phase II testing in humans and will shortly enter registration Phase III evaluation for the treatment of metastatic prostate cancer.

Topics: Administration, Oral; Angiogenesis Inhibitors; Animals; Clinical Trials as Topic; Drug Evaluation, Preclinical; Humans; Hydroxyquinolines; Male; Prostatic Neoplasms; Quinolines; Quinolones

Carbostyrils are quinolone derivatives, with possible growth inhibition properties on cancer cells. Unlike many tumors, 15-Lipoxygenase-1 (15-LOX-1) is highly expressed in prostate cancer (PCa) cells and has oncogenic properties. Here, with the hypothesis that 6-, 7- and 8-geranyloxycarbostyril (GQ) have inhibitory properties on 15-LOX-1, their effects were assessed on PCa cells. Their cytotoxic effects were evaluated by MTT assay and mechanism of cell death was investigated using annexin V/PI staining. Finally, the anti-tumor properties of 8-GQ were assessed in immunocompromised C57BL/6 mice bearing human PCa cells. Accordingly, these compounds could effectively inhibit 15-LOX activity in PCa cells. MTT and flow cytometry tests confirmed their toxic effects on PCa cells, with no significant toxicity on normal cells, and apoptosis was the main mechanism of cell death. In vivo results indicated that use of 8-GQ at 50 mg/kg had stronger anti-tumor effects than 5 mg/kg cisplatin, with fewer side effects on normal tissues. Therefore, 8-GQ can be introduced as a potential drug candidate with 15-LOX-1 inhibitory potency, which can be effective in treatment of prostate cancer, and should be considered for further drug screening investigations.

Topics: Animals; Antineoplastic Agents; Arachidonate 15-Lipoxygenase; Dose-Response Relationship, Drug; HeLa Cells; Humans; Hydroxyquinolines; Lipoxygenase Inhibitors; Male; Mice; Mice, Inbred C57BL; Prostatic Neoplasms; Quinolones; Xenograft Model Antitumor Assays

Human lysine demethylase (KDM) enzymes (KDM1-7) constitute an emerging class of therapeutic targets, with activities that support growth and development of metastatic disease. By interacting with and co-activating the androgen receptor, the KDM4 subfamily (KDM4A-E) promotes aggressive phenotypes of prostate cancer (PCa). Knockdown of KDM4 expression or inhibition of KDM4 enzyme activity reduces the proliferation of PCa cell lines and highlights inhibition of lysine demethylation as a possible therapeutic method for PCa treatment. To address this possibility, we screened the ChemBioNet small molecule library for inhibitors of the human KDM4E isoform and identified several compounds with IC

Topics: Benzimidazoles; Cell Line, Tumor; Cell Proliferation; Demethylation; Enzyme Inhibitors; Histone Demethylases; Histones; Humans; Hydroxyquinolines; Jumonji Domain-Containing Histone Demethylases; Lysine; Male; PC-3 Cells; Prostatic Neoplasms; Pyrazolones; Receptors, Androgen; Transcription, Genetic

Copper 8-hydroxyquinoline-2-carboxaldehyde-thiosemicarbazide (CuHQTS) and copper 8-hydroxyquinoline-2-carboxaldehyde-4,4-dimethyl-3-thiosemicarbazide (CuHQDMTS) are two copper thiosemicarbazone complexes with potent anticancer activity on cisplatin-resistant neuroblastoma cells. This study aimed to evaluate anti-prostate cancer activity of these two copper complexes in vitro. Both CuHQTS and CuHQDMTS inhibited proliferation of prostate cancer cells and showed cytotoxicity on prostate cancer cells carrying green fluorescent protein (GFP) by fluorescent microscopic imaging. The findings of this study demonstrated anti-prostate cancer activity of CuHQTS and CuHQDMTS and suggested that GFP-carrying prostate cancer cells might be used for testing anticancer activity of copper complexes by fluorescent microscopic imaging.

Topics: Antineoplastic Agents; Cell Proliferation; Copper; Humans; Hydroxyquinolines; Image Processing, Computer-Assisted; Male; Microscopy, Fluorescence; Prostatic Neoplasms; Semicarbazides; Structure-Activity Relationship; Tumor Cells, Cultured

Linomide, Figure 1, produces robust and consistent in vivo growth inhibition of prostate cancer models via its anti-angiogenic activity and inhibition of autoimmune encephalomyelitis models of multiple sclerosis (MS). MS clinical trials were discontinued because of unacceptable toxicity, due to dose-dependent induction of proinflammation.. Therefore, linomide analogs were initially screened to determine their in vivo potency to inhibit growth of the Dunning R-3327 AT-1 rat prostate cancer model in rats and their potency to inhibit angiogenesis in a Matrigel assay in mice.. Based upon its superior potency (i.e., 30- to 60-fold more potent than linomide) in these assays and its lack of a proinflammation in the Beagle-dog, ABR-215050 (tasquinimod), Figure 1, was characterized for dose-response ability to inhibit the growth of a series of four additional human and rodent prostate cancer models in mice. Pharmacokinetic analysis following oral dosing documented that blood and tumor tissue levels of ABR-215050 as low as 0.5-1 microM are therapeutically effective. This efficacy is correlated with inhibition of angiogenesis in a variety of assays (endothelial capillary tube formation, aortic ring assay, chorioallantoic membrane assay, real-time tumor blood flow and PO(2) measurements, tumor blood vessel density, and tumor hypoxic and apoptotic fractions).. Based upon its robust and consistent anti-angiogenic activity and thus tumor growth, ABR-215050 has entered clinical trials for the treatment of prostate cancer.

Topics: Angiogenesis Inhibitors; Animals; Cell Growth Processes; Cell Line, Tumor; Dogs; Humans; Hydroxyquinolines; Male; Mice; Neovascularization, Pathologic; Prostatic Neoplasms; Quinolines; Quinolones; Rats; Xenograft Model Antitumor Assays

The synthesis and anti-angiogenic activities of linomide and its analogues are reported. Three of the analogues are 3.3-69 times more potent than linomide at inhibiting blood vessel formation in the CAM angiogenesis assay. These compounds possessed considerable anti-proliferative activity against isolated HUVEC cells with no activity against epithelial-derived prostate tumor cells.

Topics: Allantoin; Angiogenesis Inhibitors; Animals; Cell Division; Chick Embryo; Endothelium, Vascular; Humans; Hydroxyquinolines; Male; Membranes; Muscle, Smooth, Vascular; Prostatic Neoplasms; Regional Blood Flow; Structure-Activity Relationship; Tumor Cells, Cultured

It has been demonstrated that quinoline-3-carboxamide, linomide, inhibited angiogenesis and reduced the volume of tumors grown from human hormone-resistant prostate cancer cell lines after subcutaneous implantation in mice. However, subcutaneous xenograft models may not mimic human conditions due to the absence of prostatic stromal cells at the ectopic site. Therefore, we investigated the influence of linomide on local tumor growth and metastasis of the human hormone-resistant prostate cancer cell line PC-3 in an orthotopic model.. In 30 athymic nude mice, 5x10(5) PC-3 cells were injected into the dorsal prostate after surgical exposure. After 7 days, group 1 (n = 15 mice) received linomide 100 mg/kg/day in the drinking water (per os). The other 15 mice (group 2) served as controls. All mice were sacrificed after 38 days followed by macroscopical and histological evaluation of local tumor growth and metastasis. Microvessel density was determined by immunohistochemical staining for von Willebrand factor as well as silver staining followed by morphometric analysis in an area of highest vessel density.. In the control group, local tumorigenicity and locoregional lymph node metastasis was 100%. The mean weight of the local tumor was 894 mg (395- 1,261 mg). The mean transversal diameter of the lymph node metastases was 4.0 mm (1.5-5. 4 mm). In the treatment group, local tumor growth and lymph node metastasis was 100% with a mean local tumor weight of 869 mg (232-1, 131 mg) and a mean lymph node metastasis diameter of 4.6 mm (1.3-5.9 mm). Microvessel density of the local tumor in the control and treatment group did not differ significantly.. Contrary to the results reported in subcutaneous animal models, linomide per os has no effect on net tumor growth and metastasis after orthotopic implantation of the human hormone-resistant prostate cancer cell line PC-3 in nude mice.

Topics: Angiogenesis Inhibitors; Animals; Cell Division; Humans; Hydroxyquinolines; Male; Mice; Mice, Nude; Neoplasm Metastasis; Neoplasm Transplantation; Prostatic Neoplasms; Tumor Cells, Cultured

Topics: Animals; Antineoplastic Agents; Drug Synergism; Humans; Hydroxyquinolines; Interleukin-12; Macrophages; Male; Melanoma, Experimental; Mice; Neovascularization, Pathologic; Prostatic Neoplasms

Since prostate cancer (PC) development involves a combination of genetic predisposition and promotional mechanisms, especially the metabolic conversion of testosterone to 5alpha dihydrotestosterone (DHT) by 5alpha reductase, how do mechanisms in man relate to prostate-seminal vesicle (P-SV) tumor development in Lobund-Wistar (L-W) rats? The disease in man and in L-W rats shares developmental mechanisms and characteristics to the extent that prevention of P-SV tumors in L-W rats could be predictive of similar results in man. The epidemiology of PC in man and P-SV tumors in L-W rats indicates that both are hormone-related diseases based on genetic predisposition, high production of androgens (which are activated to DHT by 5alpha reductase), and early development of androgen-dependent and metastasizing late androgen-independent stages of adenocarcinomas, all after long latency periods.. L-W rats at risk of developing spontaneous or induced P-SV tumors were subjected to putative antitumor agents or procedures. These included dietary restriction, testosterone ablation, soybean-derived isoflavones, antiangiogenic linomide, tamoxifen, and a vitamin D analogue.. L-W rats subjected to 1) early onset of dietary restriction manifested suppression of spontaneous and induced development of P-SV tumors; 2) testosterone-ablation by nonesterified DHT (NE-DHT) suppressed early onset of induced P-SV tumors and to a lesser extent late onset of spontaneous tumors; 3) diets containing soy protein isolate (high isoflavones) manifested marginal suppressive effects against induced P-SV tumors, but in 12-month-old rats, the development of spontaneous tumors was reduced in incidence; 4) early administrations of antiangiogenic linomide suppressed development of induced P-SV tumors and of transplanted prostate adenocarcinoma III (PA-III) tumors, but linomide had little antitumor effect against large advanced stage tumors; and 5) tamoxifen and vitamin D analogue suppressed development of P-SV tumors. Results in conditions 1-3 were negative when tested against PA-III tumors.. Developing stages of P-SV tumors were prevented in L-W rats with autochthonous spontaneous and induced tumors, but most of the agents tested were of no therapeutic benefit against advanced-stage and transplanted PA-III tumors. However, early administrations of antiangiogenic linomide suppressed early growth of induced and transplanted PA-III tumors.

Topics: Animals; Anticarcinogenic Agents; Antineoplastic Agents; Antineoplastic Agents, Hormonal; Disease Susceptibility; Estrogens, Non-Steroidal; Glycine max; Hydroxyquinolines; Isoflavones; Male; Neovascularization, Pathologic; Phytoestrogens; Plant Preparations; Prostatic Neoplasms; Rats; Rats, Wistar; Tamoxifen; Testosterone; Vitamin D

Angiogenesis and antiangiogenesis, as applied to oncology, are phenomena in which (1) tumors acquire a new blood vascular system from the host that is needed for their growth progression and metastasis; and (2) factors are produced that interfere with neovascularization, thereby inhibiting growth and metastasis of the tumor. Linomide, a chemical antiangiogenesis agent, inhibited the growth of transplanted tumors in mice and rats and inhibited the early development of metastasizing tumors induced in the prostate-seminal vesicle (P-SV) complex of genetically susceptible Lobund-Wistar (L-W) rats.. L-W rats with small induced P-SV tumors were treated with a recommended dosage of linomide (100 mg/kg BW/day) by the intraperitoneal and oral routes. The rats were monitored for the next 1-2 months, and the primary and metastatic tumors were compared with related data in drug-free tumor-bearing control rats.. P-SV tumors in linomide-treated and untreated control rats continued to grow, except that in the former (1) the tumors were marginally smaller, (2) the centers of the primary P-SV tumors had failed to grow, (3) the peripheral areas of the tumors contained actively proliferating tumor cells, and (4) metastatic P-SV tumors in the lungs were disrupted with focal areas of necrosis, but areas of intact tumor cells survived. Spread of tumor cells into the peritoneal cavity was not inhibited. Rats on orally administered linomide lived significantly longer than rats inoculated by the intraperitoneal route and untreated control rats. The dosage of linomide used showed evidence of toxicity.. Although primary and metastatic P-SV tumors were damaged in L-W rats treated with linomide, this antiangiogenic drug was of minimal therapeutic benefit to rats in which a palpable P-SV tumor had developed before onset of treatments.

Topics: Animals; Antineoplastic Agents; Body Weight; Genital Neoplasms, Male; Hydroxyquinolines; Male; Neoplasm Metastasis; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Rats, Wistar; Seminal Vesicles

Paclitaxel, bropirimine and linomide therapy was evaluated in a murine prostate cancer model. All drugs were effective in impeding tumor growth but the mechanisms of action varied. Paclitaxel inhibited bcl-2 expression suggesting an apoptotic mechanism. Bropirimine, while inhibiting bcl-2 expression also significantly depressed tumor necrosis factor-alpha (TNF-alpha) expression. In the bropirimine treated group there was also a correlation between angiogenesis and cyclin D expression. Finally, linomide significantly decreased angiogenesis. Since the mechanism of action of these drugs differ, combining them at lower doses might maintain therapeutic efficacy while reducing toxicity.

Topics: Animals; Antineoplastic Agents; Cell Division; Cytosine; Hydroxyquinolines; Immunohistochemistry; Male; Mice; Models, Biological; Paclitaxel; Prostatic Neoplasms; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Inbred F344

Tumor-associated macrophages (TAMs) can either promote angiogenesis (i.e., the formation of new blood vessels) in tumors by secreting tumor necrosis factor-alpha (TNF-alpha) or inhibit angiogenesis by producing granulocyte-macrophage colony-stimulating factor (GM-CSF), which in turn stimulates production of the antiangiogenic protein plasminogen activator inhibitor type 2 (PAI-2). We tested, alone or in combination, the anti-prostate cancer activity of agents that perturb macrophage function.. By use of enzyme-linked immunosorbent assays, we measured the effects of Linomide (roquinimex), thalidomide, pentoxifylline, and genistein on TNF-alpha and GM-CSF production in vitro by virally transformed RAW 264.7 mouse macrophages and on PAI-2 production in vitro by human macrophages. The antitumor effects of these agents were tested in vivo on transplanted Dunning R-3327 MAT-Lu rat prostate cancers; TAM numbers and blood vessel densities in these cancers were determined by use of immunocytochemistry.. Linomide selectively inhibited mouse macrophage secretion of TNF-alpha but not of GM-CSF; however, thalidomide, pentoxifylline, and genistein inhibited the production of both cytokines. Linomide, but not thalidomide or pentoxifylline, increased production of PAI-2 by human macrophages. When administered to rats bearing MAT-Lu tumors, each of the tested agents reduced TAM numbers (Linomide, by 46%; thalidomide, by 94%; pentoxifylline, by 71%; and genistein, by 96%). However, all of the agents reduced tumor blood vessel density and tumor growth, with Linomide being the most effective (44% reduction in blood vessel density and 69% inhibition of tumor growth). None of the other agents potentiated Linomide's antitumor effect.. Linomide is unique among the antiangiogenic agents tested, in that it inhibits the stimulatory effects of TAMs on tumor angiogenesis without eliminating their antiangiogenic effects, and may thus prove to be more effective against prostate cancer.

Topics: Animals; Antineoplastic Agents; Enzyme-Linked Immunosorbent Assay; Genistein; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Hydroxyquinolines; Macrophages; Male; Mice; Neovascularization, Pathologic; Pentoxifylline; Prostatic Neoplasms; Rats; Thalidomide; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

Linomide is a p.o. active antiangiogenic agent that has been demonstrated to be effective in suppressing the in vivo growth of rat and human prostatic cancer xenografts. The present studies were conducted to determine whether the angiogenic molecules, vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) and basic fibroblast growth factor (bFGF) are expressed in vitro by DU-145, PC-3, TSU-PR1, and LnCaP human prostate cancer cell lines and whether Linomide inhibits the secretion of these angiogenic molecules. Additionally, two different androgen-responsive human prostatic cancer xenograft models (i.e., PC-82 and A-2) were used to determine whether androgen ablation-induced reduction in tumor growth is associated with a reduction in tumor VEGF and/or bFGF levels. These studies demonstrated that both VEGF and bFGF proteins are expressed to different degrees in the human prostatic cancer cell lines. The secretion of VEGF but not bFGF is up-regulated by hypoxia. Linomide is unable to inhibit either basal or hypoxia-induced secretion of VEGF. Linomide also has no effect on secreted bFGF levels. Castration inhibited tumor VEGF but had no effect on bFGF levels in both the androgen-responsive PC-82 and A-2 human prostatic cancers when grown in severe combined immunodeficient mice. When given in combination, castration potentiated the inhibition of tumor growth induced by Linomide alone. This potentiation is not due to a further inhibition in tumor VEGF levels induced by castration. Although both castration and Linomide inhibit angiogenesis, the former accomplishes it by inhibiting VEGF secretion, whereas the latter has multiple effects at several steps in the angiogenic process other than VEGF secretion. Based on their different but complementary mechanisms of action, simultaneous combination of androgen ablation with Linomide enhances the anti-prostatic cancer efficacy compared to either monotherapies alone and warrants testing in humans.

Topics: Adenocarcinoma; Androgens; Animals; Cell Hypoxia; Drug Screening Assays, Antitumor; Endothelial Growth Factors; Fibroblast Growth Factor 2; Gene Expression Regulation, Neoplastic; Humans; Hydroxyquinolines; Lymphokines; Male; Mice; Mice, SCID; Neoplasm Proteins; Neoplasm Transplantation; Neoplasms, Hormone-Dependent; Neovascularization, Pathologic; Orchiectomy; Prostatic Neoplasms; Specific Pathogen-Free Organisms; Tumor Cells, Cultured; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

Escape from "castration inhibition," be it surgical or chemically induced, is still the major problem in prostate cancer treatment. New agents that can be given as adjuvant therapy are needed. Linomide has demonstrated both anti-tumor and anti-angiogenic activity with little toxicity in the Dunning R-3327 rat prostate tumor system. Therefore it was deemed essential to study the efficacy of this drug in the adjuvant situation.. Linomide, roquinimex, was administered 3 times a week i.p. alone or in conjunction with castration to rats bearing the Dunning R-3327 PAP rat prostate tumor and its effect on tumor growth analyzed. Similar experiments, in which Linomide 25 mg./kg./day was given in the drinking water were carried out in rats with the Dunning R-3327 G tumor. The effect of treatment on blood vessel density and blood flow in the tumor was also assessed using an image analysis system.. Linomide, 2.5 & 40 mg./kg., administered from the day after castration inhibited the regrowth of the Dunning R-3327 PAP tumors In addition, Linomide 40 mg./kg. administered after tumor regrowth occurred following castration(week 10) inhibited further tumor growth. Inhibition of tumor regrowth after castration was also found in the Dunning G tumor. When Linomide treatment was stopped regrowth of the tumors occurred, either in the same animal or on transplantation to new intact hosts, demonstrating that the tumor cells were still viable. Tumor blood vessel density was decreased both after castration and Linomide treatment alone, 40 and 32% respectively. On combination of castration and Linomide a 60% decrease in blood vessel density was found. This was significantly different from either of the two treatments given alone. The enhancement on combining castration and Linomide was confirmed by a further decrease in blood flow, from 19 and 22 to 12 ml. per minute/gm. tissue respectively.. Linomide, an anti-angiogenic drug, inhibits escape from "castration inhibition".

Topics: Animals; Antineoplastic Agents; Castration; Chemotherapy, Adjuvant; Humans; Hydroxyquinolines; Male; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Rats, Inbred Strains

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Female; Humans; Hydroxyquinolines; Male; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Tamoxifen

There are two distinct phases during prostatic carcinogenesis with regard to tumor blood vessel development. During the first or prevascular phase, which may persist for years, cells that have undergone some but not all of the transformation steps undergo a limited amount of net growth, producing premalignant prostatic intraepithelial neoplastic (PIN) lesions. Most of these PIN lesions do not continue net growth and do not progress to produce histologically detectable cancer. Even the PIN lesions that do progress to cancer remain of limited virulence unless they undergo conversion to the second or angiogenic phase. Once this angiogenic phase is reached, new blood vessel development is greatly enhanced within the cancer. It is this enhanced tumor angiogenesis which allows these cancers both to grow continuously and to metastasize. Thus, inhibition of angiogenesis should be an effective chemopreventive approach for prostatic carcinogenesis. Linomide is a low molecular weight, water-soluble agent with excellent p.o. absorption and bioavailability. We have previously demonstrated that daily p.o. treatment with Linomide has antiangiogenic abilities against a series of rat and human prostatic cancer xenografts growing in vivo. In the present studies, we have demonstrated using Matrigel in in vivo angiogenesis assays that daily p.o. Linomide at 25 mg/kg/day inhibits angiogenesis induced by tumor necrosis factor alpha, acidic fibroblast growth factor, basic fibroblast growth factor, and vascular endothelial growth factor. Using an N-methylnitrosourea initiation-androgen promotion model, Linomide was given p.o. at a daily dose as high as 25 mg/kg/day for at least 1 year without major toxicity while inhibiting the development of seminal vesicle/prostate cancers in male rats by >50%. Dose-response analysis demonstrated that a Linomide blood level of 50-100 microM is optimal for such chemoprevention. In addition, Linomide treatment at a dose of 25 mg/kg/day was able to inhibit by approximately 60% the incidence of N-methylnitrosourea and approximately 50% of 7,12-dimethyl-benz(a)anthracine-induced mammary carcinogenesis in female rats.

Topics: Androgens; Animals; Anticarcinogenic Agents; Carcinogens; Female; Genital Neoplasms, Male; Growth Substances; Hydroxyquinolines; Male; Mammary Neoplasms, Experimental; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Rats, Inbred Strains; Rats, Wistar; Seminal Vesicles; Sensitivity and Specificity; Tumor Necrosis Factor-alpha

Linomide, a quinoline-3-carboxamide, has the ability to inhibit the growth of prostatic cancer in vivo but not in vitro (T. Ichikawa et al., Cancer Res., 52: 3022-3028, 1992). The reason for this discrepancy is that linomide inhibits tumor growth not directly but indirectly in vivo via its ability to inhibit the angiogenic response induced within the growing prostatic cancer (J. Vukanovic, et al., Cancer Res., 53: 1833-1837, 1993). Tumor associated macrophages can stimulate angiogenesis via their ability to secrete various cytokines, particularly tumor necrosis factor alpha (TNF-alpha). Treatment of rats with linomide decreases significantly (P < 0.05), by more than 50%, the number of tumor associated macrophages within both locally invasive (i.e., from 20-40 to 10 macrophages/high power field) and highly metastatic primary prostatic cancers (i.e., from 60-70 to 15-37 macrophages/high power field). Monocytes/macrophages isolated from linomide treated rats had a decreased ability to secrete TNF-alpha when challenged in vitro with the bacterial endotoxin, lipopolysaccharide [i.e., 702 +/- 76 (SEM) ng of TNF-alpha/10(5) monocytes/macrophages from control versus 401 +/- 2 ng of TNF-alpha/10(5) monocytes/macrophages from linomide treated rats]. In addition, when rats were treated with linomide and than challenged with lipopolysaccharide in vivo, the resulting elevation in serum TNF-alpha was inhibited by approximately 50% (i.e., 4.56 +/- 1.8 ng/ml of TNF-alpha in control versus 2.9-2.2 ng/ml depending upon the dose of linomide). The ability of linomide to decrease monocyte/macrophage secretion of TNF-alpha is not immediate, however, since the secretion of TNF-alpha induced by lipopolysaccharide challenge of monocytes/macrophages isolated from untreated animals is not decreased by acute (i.e., < 4 h) linomide treatment in vitro. These results demonstrate that the ability of linomide to inhibit the secretion of TNF-alpha by monocytes/macrophages requires either additional time or host factors. To test if natural killer (NK) cells might be one of the additional host factors required for the in vivo abilities of linomide, prostatic cancer bearing rats were treated with appropriate antiserum to deplete NK cells and then tested for their response to linomide treatment. These studies demonstrated that the antitumor, antimetastatic, and antimacrophage effects of linomide were unaffected by NK cell depletion.(ABSTRACT TRUNCATED AT 400 WORDS)

Topics: Animals; Hydroxyquinolines; Killer Cells, Natural; Lipopolysaccharides; Lung Neoplasms; Macrophages; Male; Monocytes; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Rats, Inbred Strains; Tumor Necrosis Factor-alpha

Linomide, a quinoline-3-carboxamide, has growth-inhibitory effects against a series of Dunning R-3327 rat prostatic cancers in vivo [Ichikawa et al.: Cancer Res 52:3022-3028, 1992]. In addition, we have demonstrated that daily linomide treatment can inhibit angiogenic responses in nontumor-bearing rats and reduce tumor blood flow in tumor-bearing rats [Vukanovic et al.: Cancer Res 53:1833, 1993]. In the present study we have demonstrated that the reduced tumor blood flow is due to linomide's ability to inhibit tumor angiogenesis, as documented by decreased number of blood vessels in prostatic carcinomas growing in rats treated daily with linomide. Due to linomide's ability to inhibit tumor angiogenesis, and since tumor angiogenesis is required not only for the growth of the primary cancer but also for its ability to metastasize, the effect of linomide on metastasis was directly tested using a quantitation metastasis assay. These in vivo experiments demonstrated that daily linomide treatment decreased by 3-fold the extent of dissemination of cancer cells to the lungs. To test if this antimetastatic response is due to direct effects of linomide on the metastatic cells themselves as well as an induced effect upon inhibition of tumor angiogenesis, additional studies were performed. These studies demonstrated that linomide is not converted in vivo to metabolite(s) which are directly cytotoxic or cytostatic to the prostatic cancer cells themselves. These studies also demonstrated that linomide does not decrease the attachment, migration, or invasive abilities of metastatic cancer cells. These results suggest that the major mechanism for the antitumor and antimetastatic effects of linomide is via its inhibition of tumor angiogenesis. Additional studies have demonstrated that in vivo linomide treatment results in the apoptotic death of thymocytes. This cytotoxic effect is not required for linomide's antitumor effect, nor is it due to elevated plasma levels of glucocorticoid.

Topics: Alkylation; Animals; Antineoplastic Agents; Cell Adhesion; Cell Death; Cell Movement; Glucocorticoids; Hydroxyquinolines; Male; Neoplasm Invasiveness; Neoplasm Metastasis; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Rats, Inbred Strains; Thymus Gland; Time Factors

Human prostatic cancer cells have a remarkably low rate of proliferation even when they have metastasized to the bone and have become androgen independent (Berges et al., Clin. Cancer Res., 1:473-480, 1995). Due to this low proliferation, patients with such androgen-independent metastatic prostatic cancer cells are rarely treated successfully with the presently available chemotherapeutic agents. Therefore, new approaches are urgently needed which are not dependent on the rate of cancer cell proliferation for their effectiveness. One such approach is to inhibit the angiogenic response within localized and metastatic cancer deposits, since the resultant hypoxia-induced tumor cell death does not require cell proliferation. We have previously demonstrated that the quinoline-3-carboxamide, linomide, is an p.o. active agent which inhibits tumor angiogenesis and thus blood flow in a variety of rat prostatic cancers independent of their growth rate, androgen sensitivity, or metastatic ability. Because of its antiangiogenic effects, linomide treatment induces the hypoxic death of rat prostatic cancer cells, thus inhibiting their net growth and metastases. To determine whether human prostatic cancer cells are similarly sensitive to hypoxia-induced death caused by linomide inhibition of tumor angiogenesis, androgen-independent TSU and PC-3 human prostatic cancer cells were xenotransplanted into SCID mice that were either untreated or treated p.o. with linomide. These studies demonstrated that linomide treatment decreases microvessel density in both androgen-independent human prostatic cancers. Microvessel density was decreased from 1.8 +/- 0.4% of the total area in control tumors to 1.0 +/- 0.2% in linomide-treated TSU tumors [i.e., a 44% decrease in microvessel density (P < 0.05)]. Similarly, a 56% decrease (P < 0.05) was observed in the microvessel density of PC-3 tumors (i.e., 2.7 +/- 0.8% of the area in control tumor versus 1.2 +/- 0.2% in the linomide-treated tumors). This inhibition of angiogenesis increased cell death in both TSU and PC-3 cancer cells. This is reflected in both an increase in the area of necrosis and an increase in the apoptotic index in non-necrotic areas. In untreated TSU tumors, 40 +/- 2% of tumor volume was necrotic. Linomide treatment increased this necrotic percentage to 59 +/- 2% [i.e., 48% increase (P < 0.05)]. Linomide therapy also increased apoptotic cell death in non-necrotic tumor areas. In the untreated TSU tumors, 2.9 +/- 0.6% o

Topics: Adenocarcinoma; Animals; Apoptosis; Cell Division; Humans; Hydroxyquinolines; In Vitro Techniques; Male; Mice; Mice, SCID; Neoplasm Transplantation; Neovascularization, Pathologic; Prostatic Neoplasms; Transplantation, Heterologous; Tumor Cells, Cultured

Linomide (N-phenylmethyl-1,2-dihydro-4-hydroxyl-1-methyl-2-oxoquinoline-3-carboxa mide) has a reproducible in vivo antitumor effect against a series of both androgen responsive and independent Dunning R-3327 rat prostatic cancers. This antitumor effect of linomide is host mediated. One possible mechanism involving the host is that linomide has antiangiogenic activity. An indication that linomide treatment has antiangiogenic activity is the observation that prostatic cancers from linomide treated rats have more focal necrosis than sized matched tumors from untreated rats. To directly test if linomide has antiangiogenic activity, a newly developed Matrigel based quantitative in vivo angiogenic assay was used. These experiments demonstrated that linomide has dose dependent, antiangiogenic activity in vivo in the rat. Additional studies demonstrated that due to its antiangiogenic activity, linomide treatment of rats bearing prostate cancers resulted in a more than 40% decrease in tumor blood flow. Blood flow to a variety of non-tumor bearing organs was not decreased suggesting that linomide selectively inhibits angiogenesis and does not induce loss of established blood vessels. Using as a model the response of human umbilical vein endothelial cells to linomide treatment in a variety of in vitro assays, linomide was demonstrated to have cytostatic but not cytotoxic effect on human umbilical vein endothelial cells at a medium concentration of > or = 100 micrograms/ml. In addition, both endothelial cell chemotactic migration and invasion are steps in angiogenesis inhibited by linomide treatment.

Topics: Adjuvants, Immunologic; Animals; Antineoplastic Agents; Cell Adhesion; Cell Division; Cell Movement; Cells, Cultured; Endothelium, Vascular; Humans; Hydroxyquinolines; Male; Neovascularization, Pathologic; Prostatic Neoplasms; Rats; Rats, Sprague-Dawley

Linomide (N-phenylmethyl-1,2-dihydro-4-hydroxyl-1-methyl-2-oxo-quinoline-3- carboxamide) is a quinoline 3-carboxamide which previously has been demonstrated to produce immunomodulator and antitumor effects when given in vivo. To test the possible antitumor effects of linomide against prostatic cancers, rats bearing five distinct Dunning R-3327 rat prostatic cancer sublines were treated daily with i.p. injections of linomide. These studies demonstrated that linomide has a reproducible antitumor effect against all of the prostatic cancers tested regardless of their growth rate, degree of morphologic differentiation, metastatic ability, or androgen responsiveness. This antitumor effect is observed only in vivo, not in vitro, and involves a cytotoxic response of the prostatic cancer cells. This cytotoxic response results in the retardation of the growth rate (i.e., increased tumor volume doubling time) of primary prostatic cancers and in metastatic lesions. Linomide's growth retardation is reversible, and thus continuous daily treatment with linomide is required for maximal antitumor response. Pretreatment of rats with linomide before tumor inoculation has no effect in addition to that produced by initiating linomide treatment at the time of tumor inoculation. No enhancement of either natural killer cell number or natural killer cell cytotoxic activity is induced by linomide treatment in the tumor-bearing rats. In addition, depletion of natural killer cell activity via injections of asialo-GM1 antiserum does not prevent the antitumor effects of linomide in vivo. Likewise, the antitumor effects of linomide are also produced in prostatic cancer-bearing athymic nude rats. These results suggest that the requirement for host involvement in the antitumor effects of linomide against rat prostatic cancers may involve both immune and nonimmune host mechanism(s) (e.g., antiangiogenesis).

Topics: Adjuvants, Immunologic; Animals; Antineoplastic Agents; Cell Division; Cell Line; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Hydroxyquinolines; Killer Cells, Natural; Lung Neoplasms; Male; Neoplasm Transplantation; Prostatic Neoplasms; Rats; Rats, Inbred Strains; Spleen; Tumor Cells, Cultured