fenretinide and Disease-Models--Animal

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. In advanced disease stages, prognosis is poor and treatments have limited efficacy, thus novel strategies are warranted. The synthetic retinoid fenretinide (HPR) induces apoptosis in NB and melanoma cell lines. We reported an in vitro potentiation of HPR effects on melanoma cells when the drug is incorporated into GD2-targeted immunoliposomes (anti-GD2-SIL-HPR). Here, we investigated the antitumor activity of anti-GD2-SIL-HPR against NB cells, both in vitro and in vivo. Anti-GD2-immunoliposomes (anti-GD2-SIL) showed specific, competitive binding to, and uptake by, various NB cell lines. Moreover, anti-GD2-SIL-HPR presented increased selectivity and efficacy in inhibiting NB cell proliferation through the induction of apoptosis, compared to free drug and SL-HPR. In an in vivo NB metastatic model, we demonstrated that anti-GD2-SIL-HPR completely inhibited the development of macroscopic and microscopic metastases in comparison to controls. However, similar, but significantly less potent antitumor effect was observed also in mice treated with anti-GD2 immunoliposomes without HPR (anti-GD2-SIL-blank) or anti-GD2 mAb alone (P=0.0297 and P=0.0294, respectively, vs. anti-GD2-SIL-HPR). Moreover, our results clearly demonstrated that, although anti-GD2 mAb had a strong antitumor effect in this in vivo NB model, 100% curability was obtained only following treatment with anti-GD2-SIL-HPR (P<0.0001). Anti-GD2 liposomal HPR should receive clinical evaluation as adjuvant therapy of neuroblastoma.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Division; Disease Models, Animal; Fenretinide; Gangliosides; Humans; Liposomes; Mice; Neuroblastoma; Tumor Cells, Cultured

The magnitude of the problem of prostate cancer, and the failure of conventional chemotherapy and surgery to effect a marked diminution in the total number of deaths from this disease, now indicate that chemoprevention of prostatic carcinogenesis must be seriously considered. We describe the development of a new system for quantitating the process of prostatic carcinogenesis in an experimental animal, and the use of this system to demonstrate that the retinoid, 4-hydroxyphenylretinamide, the deltanoid, Ro24-5531, and the estrogen analog, tamoxifen, all are effective agents for prevention of experimental prostate cancer.

Topics: Animals; Anticarcinogenic Agents; Calcitriol; Disease Models, Animal; Drugs, Investigational; Fenretinide; Male; Neoplasm Staging; Prostatic Neoplasms; Rats; Tamoxifen; Treatment Outcome

Cystic fibrosis is the most common genetic disease, in which symptoms may be alleviated but not fully eliminated. Ceramides have long been implicated in the inflammatory etiology of cystic fibrosis, with contradicting reports with regards to their role. Recently, significant biological and biophysical differences have been observed between long- and very long-chain ceramides. This work reveals that long-chain ceramides are upregulated whereas very long-chain ceramides are downregulated in cell lines, mouse animal model, and patients with cystic fibrosis, compared with their controls. Treatment with fenretinide decreases the levels of long-chain ceramides and increases the levels of very long-chain ceramides. Our results show that restoration of cystic fibrosis conductance regulator (CFTR) expression is associated with normalization of aberrant levels of specific ceramides. This demonstrates for the first time a correlation between CFTR protein expression and regulation of specific ceramide levels. Furthermore, using cystic fibrosis lung epithelial cell lines, we demonstrate that this effect can be attributed to the transcriptional downregulation of ceramide synthase 5 (Cers5) enzyme. We also discovered a partial synergism between fenretinide and zinc (Zn. Long- and very long-chain ceramides (LCCs and VLCCs) are biochemically distinct. LCCs are upregulated whereas VLCCs are downregulated in cystic fibrosis. Fenretinide downregulates the levels of LCCs and upregulates the levels of VLCCs. Fenretinide changes the balance of LCCs and VLCCs by downregulating Cers5 enzyme. Fenretinide and zinc ions cooperate in the modulation of ceramide levels.

Topics: Adolescent; Adult; Animals; Cell Line; Ceramides; Cystic Fibrosis; Disease Models, Animal; Down-Regulation; Female; Fenretinide; Humans; Male; Mice, Inbred C57BL; Mice, Knockout; Middle Aged; PPAR gamma; Sphingosine N-Acyltransferase; Transcriptional Activation; Young Adult

Fenretinide (4-HPR), a synthetic retinoid, has attracted attention for its anti-inflammation activity. However, few studies have evaluated the effects of 4-HPR on ulcerative colitis (UC). The present study was performed to investigate the therapeutic effects of 4-HPR on UC, and to explore the mechanisms mainly focused on macrophage polarization involved in this progress. Intraperitoneally administered 4-HPR particularly at dose of 100 mg/kg obviously alleviated UC symptoms and restrained the mRNA expression of colonic IL-1β, IL-6, and TNF-α in dextran sulfate sodium (DSS)-induced mice. Further analysis showed that 4-HPR decreased the mRNA expression of M1 macrophage markers IL-12 and iNOS, while increased M2 macrophage markers Ym1, Arg1 and MRC1 in colonic tissue of mice received DSS. Consistently, an

Topics: Animals; Cell Polarity; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Fenretinide; Macrophages; Male; Mice; Mice, Inbred C57BL; Protective Agents; RAW 264.7 Cells

Amyotrophic lateral sclerosis (ALS) is the most frequent motor neuron disease for which effective treatment options are still lacking. ALS occurs in sporadic and familial forms which are clinically indistinguishable; about 20% of familial ALS cases are linked to mutations of the superoxide dismutase 1 (SOD1) gene. Fenretinide (FEN), a cancer chemopreventive and antiproliferative agent currently used in several clinical trials, is a multi-target drug which also exhibits redox regulation activities. We analyzed the effects of FEN on mutant SOD1 (mSOD1) toxicity in motoneuronal (NSC34) and a muscle (C2C12) cell lines and evaluated the impacts of chronic administration of a new nanomicellar fenretinide formulation (NanoMFen) on ALS disease progression in the SOD1

Topics: Amyotrophic Lateral Sclerosis; Animals; Disease Models, Animal; Female; Fenretinide; Mice; Mice, Transgenic; Mutant Proteins; Superoxide Dismutase; Superoxide Dismutase-1

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Fenretinide, a synthetic retinoid derivative first investigated for cancer prevention and treatment, has been shown to ameliorate glucose tolerance, improve plasma lipid profile and reduce body fat mass. These effects, together with its ability to inhibit ceramide synthesis, suggest that fenretinide may have an anti-atherosclerotic action.. To this aim, nine-week-old apoE-knockout (EKO) female mice were fed for twelve weeks a Western diet, without (control) or with (0.1% w/w) fenretinide. As a reference, wild-type (WT) mice were treated similarly. Growth and metabolic parameters were monitored throughout the study. Atherosclerosis development was evaluated in the aorta and at the aortic sinus. Blood and lymphoid organs were further characterized with thorough cytological/histological and immunocytofluorimetric analyses.. Fenretinide treatment significantly lowered body weight, glucose levels and plasma levels of total cholesterol, triglycerides, and phospholipids. In the liver, fenretinide remarkably reduced hepatic glycogenosis and steatosis driven by the Western diet. Treated spleens were abnormally enlarged, with severe follicular atrophy and massive extramedullary haematopoiesis. Severe renal hemosiderin deposition was observed in treated EKO mice. Treatment resulted in a threefold increase of total leukocytes (WT and EKO) and raised the activated/resting monocyte ratio in EKO mice. Finally, atherosclerosis development was markedly increased at the aortic arch, thoracic and abdominal aorta of fenretinide-treated mice.. We provide the first evidence that, despite beneficial metabolic effects, fenretinide treatment may enhance the development of atherosclerosis.

Topics: Animals; Antineoplastic Agents; Aorta; Aortic Diseases; Atherosclerosis; Blood Glucose; Diet, Western; Disease Models, Animal; Disease Progression; Energy Metabolism; Female; Fenretinide; Lipids; Liver; Mice, Inbred C57BL; Mice, Knockout, ApoE; Plaque, Atherosclerotic; Spleen; Weight Loss

Cystic fibrosis (CF) is the most common genetic disease in Caucasians. CF is manifested by abnormal accumulation of mucus in the lungs, which serves as fertile ground for the growth of microorganisms leading to recurrent infections and ultimately, lung failure. Mucus in CF patients consists of DNA from dead neutrophils as well as mucins produced by goblet cells. MUC5AC mucin leads to pathological plugging of the airways whereas MUC5B has a protective role against bacterial infection. Therefore, decreasing the level of MUC5AC while maintaining MUC5B intact would in principle be a desirable mucoregulatory treatment outcome. Fenretinide prevented the lipopolysaccharide-induced increase of MUC5AC gene expression, without affecting the level of MUC5B, in a lung goblet cell line. Additionally, fenretinide treatment reversed the pro-inflammatory imbalance of fatty acids by increasing docosahexaenoic acid and decreasing the levels of arachidonic acid in a lung epithelial cell line and primary leukocytes derived from CF patients. Furthermore, for the first time we also demonstrate the effect of fenretinide on multiple unsaturated fatty acids, as well as differential effects on the levels of long- compared to very-long-chain saturated fatty acids which are important substrates of complex phospholipids. Finally, we demonstrate that pre-treating mice with fenretinide in a chronic model of P. aeruginosa lung infection efficiently decreases the accumulation of mucus. These findings suggest that fenretinide may offer a new approach to therapeutic modulation of pathological mucus production in CF.

Topics: Administration, Oral; Animals; Arachidonic Acid; Cell Line; Cystic Fibrosis; Disease Models, Animal; Docosahexaenoic Acids; Fenretinide; Humans; Lung; Mice; Mice, Inbred CFTR; Mucin 5AC; Mucin-5B; Mucus; Phospholipids; Pneumonia; Pseudomonas aeruginosa; Pseudomonas Infections; Rats; Respiratory Mucosa

To assess the efficacy of the novel clinical formulation of fenretinide (LAU-7b) for the treatment of allergic asthma. To study the association between LAU-7b treatment in allergic asthma and the modulation of very long chain ceramides (VLCC).. We used two allergens (OVA and HDM) to induce asthma in mouse models and we established a treatment protocol with LAU-7b. The severity of allergic asthma reaction was quantified by measuring the airway resistance, quantifying lung inflammatory cell infiltration (Haematoxylin and eosin stain) and mucus production (Periodic acid Schiff satin). IgE levels were measured by ELISA. Immunophenotyping of T cells was done using Fluorescence-activated cell sorting (FACS) analysis. The analysis of the specific species of lipids and markers of oxidation was performed using mass spectrometry.. Our data demonstrate that 10 mg/kg of LAU-7b was able to protect OVA- and HDM-challenged mice against increase in airway hyperresponsiveness, influx of inflammatory cells into the airways, and mucus production without affecting IgE levels. Treatment with LAU-7b significantly increased percentage of regulatory T cells and CD4. 9 days of 10 mg/kg of LAU-7b daily treatment protects the mice against allergen-induced asthma and restores VLCC levels in the lungs and plasma.

Topics: Allergens; Animals; Asthma; Ceramides; Clinical Protocols; Disease Models, Animal; Drug Compounding; Female; Fenretinide; Male; Methylcellulose; Mice; Ovalbumin; Pyroglyphidae

There is a major clinical need for new therapies for the treatment of chronic itch. Many of the molecular components involved in itch neurotransmission are known, including the neuropeptide NPPB, a transmitter required for normal itch responses to multiple pruritogens in mice. Here, we investigated the potential for a novel strategy for the treatment of itch that involves the inhibition of the NPPB receptor NPR1 (natriuretic peptide receptor 1). Because there are no available effective human NPR1 (hNPR1) antagonists, we performed a high-throughput cell-based screen and identified 15 small-molecule hNPR1 inhibitors. Using in vitro assays, we demonstrated that these compounds specifically inhibit hNPR1 and murine NPR1 (mNPR1). In vivo, NPR1 antagonism attenuated behavioral responses to both acute itch- and chronic itch-challenged mice. Together, our results suggest that inhibiting NPR1 might be an effective strategy for treating acute and chronic itch.

Topics: Animals; Behavior, Animal; Cell-Free System; Dermatitis, Contact; Disease Models, Animal; Ganglia, Spinal; Humans; Mice, Inbred C57BL; Mice, Knockout; Neurons; Pruritus; Receptors, Atrial Natriuretic Factor; Reproducibility of Results; Signal Transduction; Small Molecule Libraries

Recurrent high-risk neuroblastoma is a childhood cancer that often fails to respond to therapy. Fenretinide (4-HPR) is a cytotoxic retinoid with clinical activity in recurrent neuroblastoma and venetoclax (ABT-199) is a selective inhibitor of the antiapoptotic protein B-cell lymphoma-2 (BCL-2). We evaluated activity of 4-HPR + ABT-199 in preclinical models of neuroblastoma. Patient-derived cell lines and xenografts from progressive neuroblastoma were tested. Cytotoxicity was evaluated by DIMSCAN, apoptosis by flow cytometry, and gene expression by RNA sequencing, quantitative RT-PCR, and immunoblotting. 4-HPR + ABT-199 was highly synergistic against high BCL-2-expressing neuroblastoma cell lines and significantly improved event-free survival of mice carrying high BCL-2-expressing patient-derived xenografts (PDX). In 10 matched-pair cell lines [established at diagnosis (DX) and progressive disease (PD) from the same patients], BCL-2 expression in the DX and PD lines was comparable, suggesting that BCL-2 expression at diagnosis may provide a biomarker for neuroblastomas likely to respond to 4-HPR + ABT-199. In a pair of DX (COG-N-603x) and PD (COG-N-623x) PDXs established from the same patient, COG-N-623x was less responsive to cyclophosphamide + topotecan than COG-N-603x, but both DX and PD PDXs were responsive to 4-HPR + ABT-199. Synergy of 4-HPR + ABT-199 was mediated by induction of NOXA via 4-HPR stimulation of reactive oxygen species that induced expression of ATF4 and ATF3, transcription factors for NOXA. Thus, fenretinide + venetoclax is a synergistic combination that warrants clinical testing in high BCL-2-expressing neuroblastoma.

Topics: Animals; Antineoplastic Agents; Bridged Bicyclo Compounds, Heterocyclic; Cell Culture Techniques; Cell Line, Tumor; Disease Models, Animal; Female; Fenretinide; Humans; Mice; Neuroblastoma; Proto-Oncogene Proteins c-bcl-2; Sulfonamides

Fungal keratitis is a major cause of corneal ulcers, resulting in significant visual impairment and blindness. Fenretinide, a derivative of vitamin A, has been shown to suppress inflammation in a multitude of diseases. In this study, we aimed to characterize the effect of fenretinide in Aspergillus fumigatus keratitis of the eye in a mouse model.. In vivo and in vitro experiments were performed in mouse models and THP-1 macrophage cell cultures infected with A. fumigatus, respectively. Experimental subjects were first pretreated with fenretinide, and then the effect of the compound was assessed with clinical evaluation, neutrophil staining, myeloperoxidase assay, quantitative polymerase chain reaction (qRT-PCR), and western blot.. We confirmed that fenretinide contributed to protection of corneal transparency during early mouse A. fumigatus keratitis by reducing neutrophil recruitment, decreasing myeloperoxidase (MPO) levels and increasing apoptosis. Compared with controls, fenretinide impaired proinflammatory cytokine interleukin 1 beta (IL-1β) production in response to A. fumigatus exposure with contributions by lectin-type oxidized LDL receptor 1 (LOX-1) and c-Jun N-terminal kinase (JNK).. Together, these findings demonstrate that fenretinide may suppress inflammation through reduced neutrophil recruitment and inflammatory cytokine production in A. fumigatus keratitis.

Topics: Animals; Antineoplastic Agents; Apoptosis; Aspergillosis; Aspergillus fumigatus; Cornea; Disease Models, Animal; DNA; Eye Infections, Fungal; Female; Fenretinide; Gene Expression Regulation; Interleukin-1beta; Keratitis; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; Polymerase Chain Reaction

The rapid spread of Zika virus (ZIKV) in recent years has highlighted the severe diseases associated with ZIKV infection, such as Guillain-Barré syndrome in adults and microcephaly in newborns; yet no vaccines or antivirals currently exist to prevent or treat ZIKV infection. We and others have previously identified N-(4-hydroxyphenyl) retinamide (fenretinide or 4-HPR) as an antiviral compound that inhibits dengue virus 2 (DV2) and other flaviviruses by limiting the steady-state accumulation of viral RNA. Here we show that 4-HPR potently inhibits ZIKV in mammalian cell culture and significantly reduces both serum viremia and brain viral burden in a murine model of ZIKV infection. Consistent with previous observations with dengue virus, this antiviral activity is associated with a significant reduction in the steady-state abundance of viral genomic RNA. We show this reduction is due to a major decrease in the rate of viral RNA synthesis, though not via direct inhibition of the activity of the viral replicase. These results establish 4-HPR's mode of action against DV and ZIKV and, taken with previous clinical trials that established 4-HPR's safety and tolerability, illustrate the potential utility of 4-HPR as an agent for treatment of ZIKV infection.

Topics: Animals; Antiviral Agents; Cell Line; Dengue Virus; Disease Models, Animal; Female; Fenretinide; Humans; Male; Mice; Mice, 129 Strain; RNA, Viral; Viral Load; Viral Plaque Assay; Virus Replication; Zika Virus; Zika Virus Infection

ABT-751 is a colchicine-binding site microtubule inhibitor. Fenretinide (4-HPR) is a synthetic retinoid. Both agents have shown activity against neuroblastoma in laboratory models and clinical trials. We investigated the antitumor activity of 4-HPR + the microtubule-targeting agents ABT-751, vincristine, paclitaxel, vinorelbine, or colchicine in laboratory models of recurrent neuroblastoma. Drug cytotoxicity was assessed in vitro by a fluorescence-based assay (DIMSCAN) and in subcutaneous xenografts in nu/nu mice. Reactive oxygen species levels (ROS), apoptosis, and mitochondrial depolarization were measured by flow cytometry; cytochrome c release and proapoptotic proteins were measured by immunoblotting. 4-HPR + ABT-751 showed modest additive or synergistic cytotoxicity, mitochondrial membrane depolarization, cytochrome c release, and caspase activation compared with single agents in vitro; synergism was inhibited by antioxidants (ascorbic acid, α-tocopherol). 4-HPR + ABT-751 was highly active against four xenograft models, achieving multiple maintained complete responses. The median event-free survival (days) for xenografts from 4 patients combined was control = 28, 4-HPR = 49, ABT-751 = 77, and 4-HPR + ABT-751 > 150 (P < 0.001). Apoptosis (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, TUNEL) was significantly higher in 4-HPR + ABT-751-treated tumors than with single agents (P < 0.01) and was inhibited by ascorbic acid and α-tocopherol (P < 0.01), indicating that ROS from 4-HPR enhanced the activity of ABT-751. 4-HPR also enhanced the activity against neuroblastoma xenografts of vincristine or paclitaxel, but the latter combinations were less active than 4-HPR + ABT-751. Our data support clinical evaluation of 4-HPR combined with ABT-751 in recurrent and refractory neuroblastoma. Mol Cancer Ther; 15(11); 2653-64. ©2016 AACR.

Topics: Animals; Antineoplastic Agents; Antioxidants; Apoptosis; Caspases; Cell Line, Tumor; Cell Survival; Cytochromes c; Disease Models, Animal; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Fenretinide; Humans; Membrane Potential, Mitochondrial; Mice; Neoplasm Recurrence, Local; Neuroblastoma; Reactive Oxygen Species; Sulfonamides; Tumor Burden; Xenograft Model Antitumor Assays

Fenretinide is a novel anticancer agent reported to exhibit anti-invasive and antimetastatic activities. It has also been shown to improve obesity and diabetes, although the effects of fenretinide on hypertension are still unknown, and the detailed mechanisms remain unclear. In this study, we have shown that treatment with lipopolysaccharide (LPS) decreased the expression of peroxisome proliferator-activated receptor γ (PPARγ) in RAW264.7 macrophages, and pretreatment with fenretinide reversed the effect of LPS on PPARγ expression. In addition, LPS-induced pro-inflammatory cytokine production, including tumor necrosis factor-α, interleukin 6, and monocyte chemoattractant protein 1 were dose-dependently reversed by fenretinide, and the effects of fenretinide on LPS-induced pro-inflammatory cytokine production were blocked by treatment with PPARγ antagonist. Moreover, fenretinide decreased LPS-induced inducible nitric oxide synthase expression and nitrogen oxide production. These effects were blocked by the pretreatment with PPARγ antagonist in a dose-dependent manner, indicating fenretinide activated PPARγ to exert anti-inflammation activity. In view of the role of inflammation in hypertension and the anti-inflammatory action of fenretinide, we found that administration of fenretinide in spontaneously hypertensive rats significantly decreased blood pressure. Taken together, these results indicate that fenretinide might be a potent antihypertensive agent that works by suppressing inflammation via activating PPARγ.

Topics: Animals; Anti-Inflammatory Agents; Antihypertensive Agents; Blood Pressure; Disease Models, Animal; Dose-Response Relationship, Drug; Fenretinide; Hypertension; Lipopolysaccharides; Macrophage Inflammatory Proteins; Macrophages; Mice; Nitric Oxide; Nitric Oxide Synthase Type II; PPAR gamma; Rats, Inbred SHR; RAW 264.7 Cells; Signal Transduction

Dengue virus (DENV) is estimated to cause 390 million infections each year, but there is no licensed vaccine or therapeutic currently available.. We describe a novel, high-throughput screen to identify compounds inhibiting the interaction between DENV nonstructural protein 5 and host nuclear transport proteins. We document the antiviral properties of a lead compound against all 4 serotypes of DENV, antibody-dependent enhanced (ADE) infection, and ex vivo and in vivo DENV infections. In addition, we use quantitative reverse-transcription polymerase chain reaction to examine cellular effects upon compound addition.. We identify N-(4-hydroxyphenyl) retinamide (4-HPR) as effective in protecting against DENV-1-4 and DENV-1 ADE infections, with 50% effective concentrations in the low micromolar range. 4-HPR but not the closely related N-(4-methoxyphenyl) retinamide (4-MPR) could reduce viral RNA levels and titers when applied to an established infection. 4-HPR but not 4-MPR was found to specifically upregulate the protein kinase R-like endoplasmic reticulum kinase arm of the unfolded protein response. Strikingly, 4-HPR but not 4-MPR restricted infection in peripheral blood mononuclear cells and in a lethal ADE-infection mouse model.. 4-HPR is a novel antiviral that modulates the unfolded protein response, effective against DENV1-4 at concentrations achievable in the plasma in a clinical setting, and provides protection in a lethal mouse model.

Topics: Active Transport, Cell Nucleus; Animals; Antiviral Agents; Carrier Proteins; Cell Line; Dengue; Dengue Virus; Disease Models, Animal; eIF-2 Kinase; Fenretinide; Humans; Mice; Protein Binding; Protein Transport; Signal Transduction; Tretinoin; Unfolded Protein Response; Viral Nonstructural Proteins; Virus Replication

Excessive accumulation of lipofuscin is associated with pathogenesis of atrophic age-related macular degeneration (AMD) and Stargardt disease. Pharmacologic inhibition of the retinol-induced interaction of retinol-binding protein 4 (RBP4) with transthyretin (TTR) in the serum may decrease the uptake of serum retinol to the retina and reduce formation of lipofuscin bisretinoids. We evaluated in vitro and in vivo properties of the new nonretinoid RBP4 antagonist, A1120.. RBP4 binding potency, ability to antagonize RBP4-TTR interaction, and compound specificity were analyzed for A1120 and for the prototypic RBP4 antagonist fenretinide. A1120 ability to inhibit RPE65-mediated isomerohydrolase activity was assessed in the RPE microsomes. The in vivo effect of A1120 administration on serum RBP4, visual cycle retinoids, lipofuscin bisretinoids, and retinal visual function was evaluated using a combination of biochemical and electrophysiologic techniques.. In comparison to fenretinide, A1120 did not act as a RARα agonist, while exhibiting superior in vitro potency in RBP4 binding and RBP4-TTR interaction assays. A1120 did not inhibit isomerohydrolase activity in the RPE microsomes. A1120 dosing in mice induced 75% reduction in serum RBP4, which correlated with reduction in visual cycle retinoids and ocular levels of lipofuscin fluorophores. A1120 dosing did not induce changes in kinetics of dark adaptation.. A1120 significantly reduces accumulation of lipofuscin bisretinoids in the Abca4(-/-) animal model. This activity correlates with reduction in serum RBP4 and visual cycle retinoids confirming the mechanism of action for A1120. In contrast to fenretinide, A1120 does not act as a RARα agonist indicating a more favorable safety profile for this nonretinoid compound.

Topics: Animals; Antineoplastic Agents; ATP-Binding Cassette Transporters; Cattle; Disease Models, Animal; Fenretinide; Humans; Hydrolases; Ligands; Lipofuscin; Macular Degeneration; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Mutant Strains; Piperidines; Prealbumin; Retinoids; Retinol-Binding Proteins, Plasma

The major limitation to successful chemotherapy of neuroblastoma (NB) is the toxicity and the poor bioavailability of traditional drugs.. We synthesised an amphiphilic dextrin derivative (DX-OL) able to host fenretinide (4-HPR) by complexation. In this study, we have investigated the effects of 4-HPR-loaded amphipilic dextrin (DX-OL/4-HPR) in comparison with 4-HPR alone both in vitro on human NB cells and in vivo in pseudometastatic NB models. The haemolysis assay was used as a measure of the potential damage caused by the pharmaceutical formulation in vivo. Pharmacokinetic experiments were performed to assess drug plasma levels in mice treated with free or complexed 4-HPR.. DX-OL/4-HPR exerted a more potent cytotoxic activity on NB cells. Complexed 4-HPR significantly increased the proportion of sub-G1 cells with respect to free 4-HPR. Dextrin derivatives showed no haemolytic activity, indicating their suitability for parenteral administration. DX-OL/4-HPR increased the lifespan and the long-term survival of treated mice over controls. The analysis of drug plasma levels indicates that the complexed drug has a higher AUC due to a reduced clearance from the blood.. Our data suggest that DX-OL/4-HPR is an injectable formulation that is able to improve drug aqueous solubility and bioavailability.

Topics: Animals; Antineoplastic Agents; Apoptosis; Biological Availability; Cell Division; Cell Line, Tumor; Disease Models, Animal; Drug Delivery Systems; Female; Fenretinide; Humans; Infusions, Intravenous; Mice; Mice, Nude; Neuroblastoma

The inflammatory response is thought to contribute to secondary damage after spinal cord injury (SCI). Polyunsaturated fatty acids (PUFAs) play an important role in the onset and resolution of inflammation. Arachidonic acid (AA), an omega-6 PUFA, contributes to the initiation of inflammatory responses, whereas docosahexaenoic acid (DHA), an omega-3 PUFA, has antiinflammatory effects. Therefore, decreasing AA and increasing DHA levels after SCI might be expected to attenuate inflammation after SCI and promote tissue protection and functional recovery. We show here that daily oral administration of fenretinide after spinal cord contusion injury led to a significant decrease in AA and an increase in DHA levels in plasma and injured spinal cord tissue. This was accompanied by a significant reduction in tissue damage and improvement in locomotor recovery. Fenretinide also reduced the expression of proinflammatory genes and the levels of oxidative stress markers after SCI. In addition, in vitro studies demonstrated that fenretinide reduced TNF-alpha (tumor necrosis factor-alpha) expression by reactive microglia. These results demonstrate that fenretinide treatment after SCI can reduce inflammation and tissue damage in the spinal cord and improve locomotor recovery. These beneficial effects may be mediated via the ability of fenretinide to modulate PUFA homeostasis. Since fenretinide is currently in clinical trials for the treatment of cancers, this drug might be a good candidate for the treatment of acute SCI in humans.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Anticarcinogenic Agents; Arachidonic Acid; Biomarkers; Cytoprotection; Disease Models, Animal; Docosahexaenoic Acids; Drug Administration Schedule; Fatty Acids, Unsaturated; Female; Fenretinide; Gene Expression Regulation; Inflammation Mediators; Mice; Mice, Inbred BALB C; Microglia; Nerve Degeneration; Neuroprotective Agents; Oxidative Stress; Recovery of Function; Spinal Cord Injuries; Tumor Necrosis Factor-alpha

Patients with cystic fibrosis (CF) and Cftr-knockout mice (CF mice) display an imbalance in fatty acids, with high arachidonic acid (AA) and low docosahexaenoic acid (DHA) concentrations. Our recent studies demonstrated defects in another class of lipids, ceramides, in patients with CF and in CF mice. This study investigates the relationship between ceramide, AA, DHA, and the correction of lipid imbalances in CF mice after treatment with fenretinide. Concentrations of AA, DHA, and ceramide were assessed in plasma from 58 adult patients with CF and 72 healthy control subjects. After 28 days of treatment with fenretinide, the same analysis was performed in wild-type and CF mice from plasma and organs (lung, ileum, pancreas, and liver). Low ceramide levels were associated with high AA and low DHA concentrations in patients with CF. No correlation was observed in healthy control subjects. Greater deficiencies were seen in patients with CF who were diagnosed before the age of 18, specifically with statistically significant higher levels of AA. Treatment with fenretinide (N-(4-hydroxyphenyl)retinamide; 4-HPR) normalized high levels of AA and low levels of ceramide, and increased the levels of DHA in CF mice. As in patients with CF, low ceramide levels correlated with higher AA and lower DHA levels in plasma of CF mice. Lipid abnormalities correlated with ceramide deficiencies in patients with CF and CF mice. We found that fenretinide treatment normalizes the fatty acid imbalance in CF mice with reducing AA to WT levels and increasing DHA. We propose that fenretinide treatment might improve this pathological phenotype in patients with CF.

Topics: Adolescent; Adult; Aged; Animals; Arachidonic Acid; Case-Control Studies; Ceramides; Cystic Fibrosis; Disease Models, Animal; Docosahexaenoic Acids; Female; Fenretinide; Forced Expiratory Volume; Humans; Ileum; Liver; Lung; Male; Mice; Mice, Inbred CFTR; Middle Aged; Pancreas; Pseudomonas aeruginosa; Pseudomonas Infections; Severity of Illness Index; Young Adult

Fenretinide, N-(4-hydroxyphenyl)retinamide (4-HPR) is an aminophenol-containing synthetic retinoid derivative of all-trans-retinoic acid, which is a potent chemopreventive and antiproliferative agent against various cancers. Clinical studies of 4-HPR have shown side effects consisting of night blindness and ocular toxicity. To maintain potent anticancer activity without side effects, p-dodecylaminophenol (p-DDAP) was designed based on structure-activity relationships of 4-HPR. In our study, we investigate whether p-DDAP shows anticancer activity against human prostate cancer cell line PC-3 when compared with 4-HPR. p-DDAP inhibited PC-3 cell growth progressively from low to high concentration in a dose-dependent manner. p-DDAP was the most potent antiproliferative agent in vitro among 6 p-alkylaminophenols and 3 4-hydroxyphenyl analogs examined including 4-HPR. Cells treated with p-DDAP were shown to undergo apoptosis, based on condensation nuclei, cytofluorimetric analysis, propidium iodide staining and the expression of bcl-2 and caspase 3. p-DDAP arrested the S phase of the cell cycle, while 4-HPR arrested the G(0)/G(1) phase. In addition, both the i.v. and i.p. administration of p-DDAP suppressed tumor growth in PC-3-implanted mice in vivo. p-DDAP showed no effects on blood retinol concentrations, in contrast to reductions after 4-HPR administration. These results indicate that p-DDAP exhibits excellent anticancer efficacy against hormonal independent prostate cancer in vitro and in vivo, and it may have great potential for clinical use in the treatment of prostate cancer with reduced side effects.

Topics: Aminophenols; Animals; Antineoplastic Agents; Apoptosis; Caspase 3; Cell Cycle; Disease Models, Animal; Fenretinide; Humans; Male; Mice; Mice, Inbred BALB C; Prostatic Neoplasms; Proto-Oncogene Proteins c-bcl-2; Tumor Cells, Cultured; Vitamin A

To evaluate the effect of N-4-hydroxyphenyl retinamide (4-HPR) on experimental laser-induced choroidal neovascularization (CNV) and on the expression and secretion of relevant growth factors by cultured human retinal pigment epithelial (RPE) cells.. CNV was induced by laser photocoagulation in C57BL/6 mice. 4-HPR (0.2 or 1 mg) or vehicle, was injected intraperitoneally twice daily for 14 days. Plasma and tissue levels of 4-HPR were measured by HPLC. CNV was evaluated by fluorescein angiography, histology, and quantitative confocal analysis of isolectin B4 histochemistry on days 7 and 14. Induction of apoptosis and expression and secretion of growth factors was studied in 4-HPR-treated RPE cultures.. Mice treated with 4-HPR exhibited time- and dose-dependent increases in plasma and tissue 4-HPR levels. CNV lesions showed increased volume with increased vascular leakage and contained fewer lesion-associated RPE in treated versus untreated mice. Treatment of nonpolarized RPE cultures with 4-HPR in the presence of serum resulted in RPE apoptosis; however, apoptosis was minimal in similarly treated highly polarized RPE. Treatment of RPE cells with 4-HPR resulted in the upregulation of VEGF-A and -C (P < 0.05) and Ang-1 (P < 0.01) mRNA and increased secretion of VEGF-A and -C (P < 0.05), whereas pigment epithelium-derived growth factor (PEDF) and thrombospondin (TSP)-1 mRNA expression and secretion were downregulated (P < 0.05).. 4-HPR increases lesion size and leakage in laser-induced CNV and is associated with the upregulation of key proangiogenic factors and the downregulation of antiangiogenic factors. Consistent with the preferential loss of RPE in CNV lesions in vivo, 4-HPR induces apoptosis of nonpolarized RPE in the presence of serum.

Topics: Angiogenesis Inducing Agents; Angiopoietin-1; Animals; Apoptosis; Blotting, Western; Cells, Cultured; Choroid; Choroidal Neovascularization; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Eye Proteins; Fenretinide; Fluorescein Angiography; In Situ Nick-End Labeling; Injections, Intraperitoneal; Laser Coagulation; Male; Mice; Mice, Inbred C57BL; Nerve Growth Factors; Pigment Epithelium of Eye; RNA, Messenger; Serpins; Thrombospondin 1; Time Factors; Up-Regulation; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor C

4-(N-hydroxyphenyl) retinamide (4-HPR) and the oral contraceptives (OCP) are currently being used alone, and in combination, for the prevention of ovarian cancer. However, the mechanism of their effects has not been studied. Non-human primate models are ideal for studying the role of these and other drugs for cancer chemoprevention because of the genetic similarity between primates and humans in respect to hormone regulation and menstrual cycle. 4-HPR and OCP were administered to sixteen female adult Macacca mulatta (Rhesus macaques) for three months alone and in combination. Laparotomy was performed before and after treatment, and ovarian biopsies were obtained to evaluate the expression of retinoid and hormone receptors, and apoptosis. ER alpha was undetectable, but ER beta, PR, RXR alpha, and RXR gamma were constitutively expressed in the ovaries. 4-HPR induced RXR alpha and RXR gamma expression at a low level and, OCP induced expression of ER beta. However, the combination of 4-HPR with OCP had a larger effect on expression of retinoid receptors. Apoptosis was detected in the 4-HPR group (equivalent dose: 200 mg/day).

Topics: Animals; Anticarcinogenic Agents; Apoptosis; Combined Modality Therapy; Contraceptives, Oral; Disease Models, Animal; Female; Fenretinide; Macaca mulatta; Ovarian Neoplasms; Ovary; Receptors, Estrogen; Receptors, Progesterone; Receptors, Retinoic Acid; Retinoid X Receptors; Reverse Transcriptase Polymerase Chain Reaction

Fenretinide [N-(4-hydroxyphenyl)retinamide or 4-HPR] is a synthetic retinoid analogue with antitumor and chemopreventive activities. N-(4-Methoxyphenyl)retinamide (4-MPR) is the most abundant metabolite of 4-HPR detected in human serum following 4-HPR therapy. We have shown in in vitro studies that 4-HPR and 4-MPR can act independent of the classic nuclear retinoid receptor pathway and that 4-HPR, but not 4-MPR, can also activate nuclear retinoid receptors. In this study, we have compared the chemopreventive effects of topically applied 4-HPR and 4-MPR with the primary biologically active retinoid, all-trans retinoic acid (ATRA), in vivo in the mouse skin two-stage chemical carcinogenesis model. All three retinoids suppressed tumor formation but the effect of 4-HPR and 4-MPR, and not of ATRA, was sustained after their discontinuation. The tumor-suppressive effects of 4-HPR and 4-MPR were quantitatively and qualitatively similar, suggesting that the two may be acting through the same retinoid receptor-independent mechanism(s). We further explored this effect in vitro by analyzing primary cultures of mouse keratinocytes treated with the same retinoids. All three could induce apoptosis with a 48-hour treatment and only ATRA and 4-HPR induced an accumulation of cells in the G1 phase of the cell cycle. This finding is consistent with our previous results showing that the effects of phenylretinamides on the cell cycle are retinoid receptor dependent whereas apoptosis induction is not. A microarray-based comparison of gene expression profiles for mouse skin treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) alone and TPA + 4-HPR or TPA + 4-MPR reveals a high degree of coincidence between the genes regulated by the two phenylretinamides. We propose that 4-HPR may exert therapeutic and chemopreventive effects by acting primarily through a retinoid receptor-independent mechanism(s) and that 4-MPR may contribute to the therapeutic effect of 4-HPR by acting through the same retinoid receptor-independent mechanism(s).

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle; Chemoprevention; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Fenretinide; G1 Phase; Gene Expression Profiling; In Vitro Techniques; Keratinocytes; Mice; Mice, Inbred SENCAR; Oligonucleotide Array Sequence Analysis; Retinoid X Receptors; Skin Neoplasms; Tetradecanoylphorbol Acetate; Tretinoin; Tumor Suppressor Proteins

The objective of this study was to evaluate the intravesical application of N-(4-hydroxyphenyl) retinamide (4-HPR) and adriamycin (ADM), as a treatment modality in a an animal model of chemically-induced bladder cancer. Bladder cancer developed in 50.0% of female Wistar rats, 4-6 weeks after intravesical application of the chemical carcinogen, N-methyl-N-nitrosourea (MNU). There was no significant difference in side effects induced by local versus systemic 4-HPR. Although tumor growth was inhibited by 4-HPR and ADM alone, tumor size was lower when both agents were used together. Apoptosis occurred at a higher rate in the combination group than when 4-HPR or ADM was used alone. The results suggest that intravesical use of 4-HPR and ADM may increase their efficacy in treatment of bladder cancer.

Topics: Administration, Intravesical; Alkylating Agents; Animals; Antibiotics, Antineoplastic; Antineoplastic Agents; Apoptosis; Cell Cycle; Disease Models, Animal; Doxorubicin; Female; Fenretinide; Flow Cytometry; In Situ Nick-End Labeling; Methylnitrosourea; Rats; Rats, Wistar; Urinary Bladder Neoplasms

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. In advanced disease stages, prognosis is poor and treatments have limited efficacy, thus novel strategies are warranted. The synthetic retinoid Fenretinide (HPR) induces apoptosis in NB and melanoma cell lines. We reported an in vitro potentiation of HPR effects on melanoma cells when the drug is incorporated into GD2-targeted immunoliposomes (anti-GD2-SIL-HPR). We investigated the antitumor activity of anti-GD2-SIL-HPR against NB cells, both in vitro and in vivo. Anti-GD2-SIL showed specific, competitive binding to and uptake by, various NB cell lines. In in vitro cytotoxicity studies, NB cells, incubated with 30 microM HPR entrapped in anti-GD2-immunoliposomes, showed a significant reduction in cellular growth compared to free HPR, HPR entrapped in Ab-free liposomes or anti-GD2 empty liposomes. In an in vivo NB metastatic model, we demonstrated that anti-GD2-SIL-HPR completely inhibited the development of macroscopic and microscopic metastases in comparison to controls. Similar, but significantly less potent, antitumor effect was observed also in mice treated with anti-GD2 immunoliposomes without HPR (anti-GD2-SIL-blank) or anti-GD2 MAb alone (p = 0.0297 and p = 0.0294, respectively, vs. anti-GD2-SIL-HPR). Moreover, our results clearly demonstrated that although anti-GD2 MAb had a strong antitumor effect in this in vivo NB model, 100% curability was obtained only after treatment with anti-GD2-SIL-HPR (p < 0.0001). Anti-GD2 liposomal HPR should receive clinical evaluation as adjuvant therapy of neuroblastoma.

Topics: Animals; Apoptosis; Cell Division; Disease Models, Animal; Fenretinide; Humans; Liposomes; Mice; Mice, Nude; Neoplasm Metastasis; Neoplasm Transplantation; Neuroblastoma; Survival Analysis; Time Factors; Tumor Cells, Cultured

Retinoblastoma arises from a subset of developing retinal cells lacking the RB-1 gene product pRB, which have lost the ability to respond to apoptotic signals. A better understanding of retinoblastoma biological response to therapeutic agents with low toxicity could improve the development of novel approaches for treatment and prevention of the disease. Naturally occurring retinoids inhibit growth and induce differentiation of Y79 human retinoblastoma cells in vitro. The synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) has been shown to induce apoptosis and/or necrosis of tumor cells of neuroectodermal origin. We examined the sensitivity of Y79 retinoblastoma cells to 4HPR in vitro, and in a xenograft model of tumor growth in nude mice in vivo. 4HPR treatment in the range 2.5 to 10 microM induced a loss of Y79 cell viability, as determined by crystal violet, trypan blue exclusion, and long-term clonogenic assays, and impairment of mitochondrial function detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Reactive oxygen species were elevated in 4HPR-treated cells and antioxidants rescued cell viability, indicating that 4HPR-induced cell death was mediated by oxidative stress. 4HPR inhibited growth of Y79 xenografts in vivo in both chemoprevention and intervention settings. Tumor growth inhibition by 4HPR was also associated with significant inhibition of angiogenesis in vivo. These findings could have an important translational value for chemoprevention or early intervention in the treatment of retinoblastoma.

Topics: Animals; Antineoplastic Agents; Cell Death; Cell Survival; Disease Models, Animal; Fenretinide; Humans; Mice; Mice, Nude; Neoplasm Transplantation; Neoplasms, Experimental; Neovascularization, Pathologic; Reactive Oxygen Species; Retinoblastoma; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Moderate reductions (< or = 15%) in body weight gain, similar to those observed after administration of some chemopreventive agents in chemically induced mammary cancer models, will result in decreased mammary cancers (up to 55%). The objective of this study was to determine whether changes in mammary gland differentiation, proliferation, apoptosis, and estradiol and progesterone levels are affected by moderate reductions in body weight induced after chemopreventive agent treatment and dietary restriction. The body weights of female Sprague-Dawley rats were reduced by dietary restrictions to match those of rats receiving 4-hydroxyphenylretinamide (4-HPR) at a dose known to inhibit methylnitrosourea (MNU)-induced mammary cancers. 4-HPR supplementation or dietary restrictions began 1 wk before MNU administration at 50 days of age. Mammary gland differentiation, proliferation, apoptosis, and serum levels of estradiol and progesterone were measured at 50, 57, and 71 days of age. Casein expression, proliferating cellular nuclear antigen expression, and apoptosis were not significantly different from controls in the dietary-restricted group. Proliferating cellular nuclear antigen expression was significantly lower in 4-HPR-treated animals than in controls at 57 days of age. The diameter of the mammary gland ducts was smaller at 71 days of age in the treatment groups. A decrease in estradiol levels for each group was observed at 50 days of age, but not at later time points. Progesterone levels were reduced in the 4-HPR group, but not in the dietary-restricted group, during each time period. It would appear that the observed decrease in mammary cancers observed with moderate reductions in body weight gain might be due to multiple related factors different from those related to 4-HPR treatment.

Topics: Alkylating Agents; Animals; Anticarcinogenic Agents; Apoptosis; Blotting, Northern; Body Weight; Diet, Reducing; Disease Models, Animal; Estradiol; Female; Fenretinide; Mammary Glands, Animal; Mammary Neoplasms, Experimental; Methylnitrosourea; Progesterone; Proliferating Cell Nuclear Antigen; Rats; Rats, Sprague-Dawley

The objective of this study was to explore whether a nonhuman primate model could be developed to test drugs for the prevention of ovarian cancer.. Nineteen adult female Rhesus macaques were given fenretinide (4HPR), oral contraceptives (OCP), the combination (4HPR + OCP), or no medication for 3 months. Exploratory laparotomy was done pre- and postdrug to assess intermediary biomarkers of neoplastic phenotype, proliferation, response pathways, and growth-regulatory and metabolic markers. Fluorescence emission spectra were plotted for each group pre- and postdrug and means were overlaid on these plots and normalized. Fluorescence intensities were compared using the 2-tailed Student t test, (P = 0.1-0.01).. All monkeys tolerated drugs and surgeries without difficulty. Histochemical markers showed no significant trend. However, fluorescence spectroscopy showed increased intensity at 450 nm excitation, 550 nm emission correlating with increased FAD presence. The 4HPR group (P = 0.01) showed higher intensity than the OCP group (P = 0.05-0.07) when compared with the controls. Decreased emission was seen at 350 nm excitation, 450 nm emission correlating with decreased NAD(P)H presence. The OCP group showed the largest change (P < 0.01), and the control group showed the smallest change.. The nonhuman primate is an excellent model to test drug effect on the ovarian surface epithelium and merits additional study. Fluorescence spectroscopy was the most sensitive marker for drug activity and the apparent increase in NAD and FAD in the 4HPR group is consistent with the effect of 4HPR observed in cell culture. The differences between the OCP and the 4HPR groups suggest a different mechanism of activity of these drugs.

Topics: Animals; Biomarkers, Tumor; Chemoprevention; Contraceptives, Oral; Disease Models, Animal; Female; Fenretinide; Macaca mulatta; Ovarian Neoplasms; Phenotype; Spectrometry, Fluorescence

The objective of the study reported here was to explore whether a nonhuman primate model could be developed for chemoprevention of ovarian cancer.. An initial feasibility trial was done with three monkeys to determine tolerance for these drugs and for acquisition of surgical ovarian biopsy specimens. In the study, 19 female adult Macacca mulatta (rhesus macaques) were given fenretinide (4HPR) oral contraceptive (OCP), the combination of 4HPR+OCP, or no medication for three months. Laparotomy was performed before and after drug administration, and ovarian biopsy specimens were obtained to evaluate the potential for this animal as a model for ovarian cancer chemoprevention, as well as evaluating fluorescence spectroscopy and other potential biomarkers for ovarian cancer prevention studies.. The monkeys tolerated the drugs, surgeries, and acquisition of multiple ovarian biopsy specimens with resultant minimal morbidity. On initial data analysis, fluorescence spectroscopy was the marker that appeared the most promising.. On the basis of results of this study, this model merits further investigation. The rhesus monkey is an excellent candidate for a nonhuman primate model for ovarian cancer chemoprevention.

Topics: Animals; Anticarcinogenic Agents; Biomarkers, Tumor; Biopsy; Contraceptives, Oral, Combined; Disease Models, Animal; Drug Combinations; Female; Fenretinide; Humans; Macaca mulatta; Mestranol; Norethindrone; Ovarian Neoplasms; Ovary; Spectrometry, Fluorescence

The expression of midkine (MK) was investigated in pancreatic ductal hyperplasias, atypical hyperplasias and adenocarcinomas induced by N-nitrosobis(2-oxopropyl)amine (BOP) in hamsters, and in hamster ductal adenocarcinoma cell lines (HPD-1NR, -2NR and -3NR). MK mRNA was clearly overexpressed in invasive pancreatic duct adenocarcinomas (PCs) and the three cell lines as assessed by northern blot analysis, and MK protein expression increased from ductal hyperplasia through atypical hyperplasias, intraductal carcinomas and invasive PCs by immunohistochemistry. The extent of overexpression of MK mRNA in PCs was almost the same as in hamster whole embryonic tissue. MK is reported to be a retinoid-responsive gene, but MK mRNA expression was not affected by treatment with all-trans retinoic acid (tRA) or N-(4-hydroxyphenyl)retinamide (4-HPR) in HPD-1NR cells. The results thus suggest that MK expression is involved in the development and progression of pancreatic ductal adenocarcinomas induced by BOP in hamsters, with loss of upregulation by retinoic acid.

Topics: Animals; Antineoplastic Agents; Blotting, Northern; Carcinoma, Pancreatic Ductal; Carrier Proteins; Cell Division; Cells, Cultured; Cricetinae; Cytokines; Disease Models, Animal; Female; Fenretinide; Gene Expression; Immunohistochemistry; Mesocricetus; Midkine; Nitrosamines; Pancreatic Neoplasms; RNA, Messenger; Tretinoin

The effects of the synthetic retinoid N-(4-hydroxyphenyl) retinamide (4-HPR) on prostate cancer metastasis in vivo were evaluated in the mouse prostate reconstitution (MPR) model. MPRs were produced by infection of either heterozygous (+/-) or nullizygous (-/-) p53-mutant fetal prostatic epithelial cells with the recombinant retrovirus Zipras/myc 9. Previous studies have documented that loss of p53 function potentiates metastasis in this model system. MPRs were grafted into homozygous (+/+) p53 male mice, fed a 4-HPR containing diet or a control diet and maintained until the status of tumor progression dictated sacrifice. Under these experimental conditions, treatment with 4-HPR did not have a significant effect on primary tumor wet weight for either p53 +/- or p53 -/- MPRs. For, p53 +/- MPRs the animals fed the 4-HPR diet had a slight improvement in survival and a significant reduction in the number of mesenteric metastases (P = 0.0477, t-test). Notably, in p53 +/- MPRs the incidence of metastasis to lumbar spine and sternum was 92% in the control animals compared to 54% in the 4-HPR treated animals (P = 0.035, chi2-test). In p53 -/- MPRs there was a trend toward a reduction in the number of soft tissue metastases to lung and liver in the 4-HPR group relative to the control diet group and a statistically significant reduction in the incidence of metastasis to bone was demonstrated in that 50% of control animals versus 30% of 4-HPR treated p53 -/- animals harbored bone metastases (P = 0 < 0.05, chi2-test). Cell lines were established from portions of the primary tumor and from selected metastatic deposits in each experimental group. Clonal analysis, by retroviral integration pattern, indicated increased clonal diversity in both the primary tumors and metastasis-derived cell lines from 4-HPR treated animals relative to the control animals. In vitro treatment with 4-HPR did not reveal discriminating differences between cell lines derived from primary tumors and bone metastases or control and treatment groups in regard to growth arrest or apoptotic responses. Overall these studies indicate limited anti-tumor and anti-metastatic activity in this highly aggressive in vivo mouse model of prostate cancer, yet 4-HPR treatment significantly suppressed the development of bone metastases in p53 +/- and p53 -/- MPRs revealing a novel and potentially clinically useful activity of this retinoid.

Topics: Animals; Antineoplastic Agents; Bone Neoplasms; Cell Division; Diet; Disease Models, Animal; Fenretinide; Male; Mice; Prostatic Neoplasms; Survival Rate; Tumor Cells, Cultured; Tumor Suppressor Protein p53

Retinoids constitute a very promising class of agents for the chemoprevention or treatment of breast cancer. These retinoids exert their biological activity through two distinct classes of retinoic acid (RA) receptors (R), the RAR isotypes (alpha, beta, and gamma) and the three RXR isotypes (alpha, beta, and gamma) and their numerous isoforms which bind as RXR/RAR heterodimers to the polymorphic cis-acting response elements of RA target genes. With respect to these numerous receptor sub-types, the retinoid-induced effects at the biological level include marked modifications with respect to both cell proliferation and cell death (apoptosis), and also in the induction of differentiation processes. The present study aims to characterize the effect which four retinoids (TTNPB, 9-cis-RA, LGD 1069, 4-HPR) with distinct RAR/RXR binding properties induced on various in vitro and in vivo mouse and human breast cancer models. The experiments with the retinoids were carried out in comparison with the anti-estrogen tamoxifen and the anti-progestagen RU-486 compounds. The results show that the 6 compounds under study were markedly more efficient in terms of growth inhibition in the human T-47D cell line when maintained under anchorage-independent culture conditions than when maintained under anchorage-dependent ones. While RU-486 exhibited a weak statistically significant (p < 0.05) influence on the growth of the T-47D stem cells, tamoxifen had a marked inhibitory influence on the growth of these cells. Of the four retinoids, 4-HPR was the least effective since the lowest doses tested (1 and 0.1 nM) exhibited no statistically (p > 0.05) significant influence on the growth of the stem cells. The most efficient retinoid was TTNPB. It was only at the highest dose (10 microM) that tamoxifen and RU-486 showed a weak inhibitory influence on the growth of the T-47D non-stem cells while all 4 retinoids exerted a significant inhibitory influence on the growth of these non-stem cells, with 4-HPR being the most efficient (P < 0.001) at the highest dose, but ineffective (P > 0.05) at the lowest. Tamoxifen and TTNPB were tested in vivo on hormone-sensitive (HS) and hormone-insensitive (HI) strains of the MXT murine mammary carcinoma. While TTNPB appeared to be equally efficient in terms of growth inhibition in both MXT-HS and MXT-HI models, tamoxifen had only a marginal inhibitory influence on the growth of the MXT-HI strain but did inhibit growth in the case of the MXT-HS one. TT

Topics: Alitretinoin; Animals; Anticarcinogenic Agents; Apoptosis; Benzoates; Bexarotene; Breast Neoplasms; Cell Division; Disease Models, Animal; Female; Fenretinide; Hormone Antagonists; Humans; Mammary Neoplasms, Animal; Mice; Mice, Inbred C57BL; Mifepristone; Retinoids; Tamoxifen; Tetrahydronaphthalenes; Tretinoin; Tumor Cells, Cultured

The activities of the retinoid, N-(4-hydroxyphenyl)-all-trans-retinamide (4-HPR) and the polyamine synthesis inhibitor, alpha-difluoromethylornithine (DFMO), as inhibitors of lymphoma induction in PIM transgenic mice were evaluated. Lymphoma was induced in male PIM mice by a single intraperitoneal injection of 50 mg N-ethyl-N-nitrosourea (ENU) per kg body weight. Continuous dietary administration of 4-HPR (391, 196 or 98 mg/kg diet) or DFMO (1000, 500 or 250 mg/kg diet) was initiated immediately after ENU administration, and was continued until the end of the study at 35 weeks. At 20 weeks post-ENU, the high dose of 4-HPR reduced both lymphoma incidence and associated mortality. However, the protection conferred by 4-HPR represented a delay rather than an inhibition of neoplastic development, since both lymphoma incidence and mortality at study termination were similar in dietary controls and all groups treated with 4-HPR. DFMO had no effect on lymphoma incidence, latency or mortality at any point in the study. These results suggest that 4-HPR or other retinoids may be effective in the prevention of lymphoma induction, whereas inhibition of polyamine biosynthesis does not appear to present a useful mechanistic target for the chemoprevention of lymphoid neoplasia. The PIM transgenic mouse provides a useful in vivo model for the rapid evaluation of chemopreventive agents.

Topics: Animals; Anticarcinogenic Agents; Disease Models, Animal; Dose-Response Relationship, Drug; Eflornithine; Fenretinide; Lymphoma; Male; Mice; Mice, Transgenic

We documented the effect of the retinoid (4-hydroxyphenyl)retinamide on collagen expression in a tissue culture and in an animal model of scleroderma.. We used RNA analysis, chloramphenicol acetyltransferase assays, organ culture, and histologic evaluation.. We showed that (4-hydroxyphenyl)retinamide decreases alpha 1(I) collagen messenger RNA and transcription in cultured cells, and decreases collagen levels in the dermis of tight-skin mice.. These results provide a basis for further experiments to address the efficacy of (4-hydroxyphenyl)retinamide in the treatment of scleroderma.

Topics: Animals; Cell Division; Collagen; Disease Models, Animal; Fenretinide; Fibroblasts; Gene Expression; Humans; Male; Mice; Mice, Mutant Strains; RNA, Messenger; Scleroderma, Systemic; Skin; Transforming Growth Factor beta

The chemopreventive retinoid N-(4-hydroxyphenyl)retinamide (HPR) depresses serum retinol and retinol-binding protein (RBP) concentrations. To study long-term effects of HPR on serum proteins, rats were fed a control diet or a diet containing HPR (737 mumol/kg diet) for 14 d. Serum retinol and RBP of HPR-treated rats decreased to 42 and 41%, respectively, of initial concentrations. Transthyretin, albumin and transferrin did not differ between treatments. Previous studies found that HPR decreased secretion of the retinol-RBP complex into plasma. To investigate acute effects of HPR on RBP metabolism, vitamin A-deficient rats were injected with HPR (51 mumol/kg body wt), retinol (0.52 mumol/rat) or Tween carrier only. Liver RBP concentrations in HPR- and retinol-treated rats were 45 and 18%, respectively, of concentrations in Tween-treated rats, indicating rapid RBP secretion. Tween- and HPR-treated rats maintained relatively constant serum RBP concentrations, whereas retinol-replete rats had 12-fold higher serum RBP after 150 min. Rats treated with HPR and rats treated with retinol had 29- and eightfold higher kidney RBP concentrations, respectively, than Tween-treated rats, indicating rapid clearance of RBP from plasma. We conclude that HPR affects RBP metabolism by inducing secretion of liver RBP into the bloodstream and rapid RBP accumulation in the kidney.

Topics: Analysis of Variance; Animals; Disease Models, Animal; Fenretinide; Kidney; Liver; Male; Prealbumin; Radioimmunoassay; Rats; Rats, Sprague-Dawley; Retinol-Binding Proteins; Retinol-Binding Proteins, Plasma; Serum Albumin; Time Factors; Transferrin; Vitamin A; Vitamin A Deficiency

Dietary calcium glucarate (CGT) increased the activity of non-toxic levels of dietary isotretinoin against pre-established tumors in the chemically-induced rat mammary tumour model. In the range of 1.0-1.5 mmol/kg diet, isotretinoin enhanced tumour growth by 20% over a 4 week course of treatment. Tumour growth inhibition not exceeding 15% was observed only at dosages as high as 2.0 mmol/kg, i.e. in the cumulative toxicity range. Growth inhibition by 64 mmol/kg diet of CGT alone was marginal, varying from zero to 8%. In contrast, the combination of 1.0 mmol/kg of isotretinoin and 64 mmol/kg of CGT caused a reversible inhibition of tumour growth, culminating in a net decrease in tumour volume of 20%. This study documents the marginal enhancement of tumour growth by high sub-optimal concentrations of isotretinoin alone, and describes conditions for inhibition of tumour growth by sub-optimal concentrations of the natural retinoid. Related in vitro studies on retinoid sensitive and insensitive cell lines suggest that the anticancer activity of the combination is dependent on sensitivity of the cells to retinoids.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Division; Diet; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Resistance; Drug Synergism; Female; Fenretinide; Glucaric Acid; Isotretinoin; Mammary Neoplasms, Experimental; Rats; Rats, Inbred Strains; Tretinoin

We studied the effects of oral administration of the retinoid, 4-hydroxyphenyl retinamide (4-HPR), on group A streptococcal cell wall-induced polyarthritis in the rat, a model characterized initially by exudative inflammation of peripheral joints followed by chronic proliferative/erosive synovitis. Experimental arthritis was induced in female LEW/N rats by i.p. injection of streptococcal cell walls in saline (15 micrograms/g body weight). Depending upon the experiment, continuous daily oral administration of the retinoid was begun either 14 days prior to induction of the disease, at the time of cell wall administration and/or 11 days and 31 days after cell wall injection. Dosage was either 1 or 2 mmol 4-HPR/kg of chow. During the course of the disease, severity of clinical illness was assessed by determination of clinical severity index, by histological or radiologic examination, and by measurement of production in vitro of collagenase and prostaglandin E2 by excised synovial tissue. In rats fed the retinoid prior to cell wall injection, both the acute and the chronic responses were suppressed. In rats given the retinoid at the time of cell wall injection, the acute inflammatory response was only partially suppressed on the diet containing 2 mmol 4-HPR/kg chow, but the chronic disease was impressively inhibited in a dose dependent manner. Similarly, in animals with established disease, the drug was also effective; however, the more advanced the illness, the less effective the drug. Clinical observations were paralleled by the histological, radiographical and biochemical analyses. Treated animals showed far less synovial proliferation and joint destruction, and synovial tissues taken from these rats produced lesser amounts of collagenase and prostaglandin E2. No significant toxicity of the retinoid was noted. We conclude that oral administration of 4-HPR suppresses, in a dose and time dependent manner, both the acute and chronic stages of streptococcal cell wall-induced arthritis in rats without apparent significant toxicity. Our data suggest that studies of the effects of this retinoid on patients with chronic inflammatory synovitis are warranted.

Topics: Animals; Arthritis; Cell Wall; Dinoprostone; Disease Models, Animal; Female; Fenretinide; Granuloma; Liver Diseases; Microbial Collagenase; Prostaglandins E; Rats; Rats, Inbred Lew; Streptococcus pyogenes; Tretinoin