piperidines and Fibrosarcoma

Canine oral fibrosarcoma (COF) is one of the most common oral tumors in dogs and carries a guarded prognosis due to a lack of effective systemic therapeutic options. Mastinib and imatinib are two commonly used tyrosine kinase inhibitors (TKIs) in veterinary oncology but their potential efficacy against COF is uncharacterized. To begin investigating the rationale for use of these TKIs against COF, the present study tested for the presence TKI targets PDGFR-α, PDGFR-β, Kit, and VEGFR-2 and examined the in vitro effects on cell viability after TKI treatment alone or with doxorubicin. Immunohistochemistry for PDGFR-α, PDGFR-β, Kit, and VEGFR-2 was performed in 6 COF tumor biopsies. Presence of these same receptors within 2 COF cell lines was probed by reverse transcription-polymerase chain reaction and, for those with mRNA detected, confirmed via western blot. Effects on cell viability were assessed using an MTS assay after masitinib or imatinib treatment alone (0-100 μM), or in combination with doxorubicin (0-3000 nM doxorubicin). Anti-PDGFRB siRNA knockdown was performed and the effect on cell viability quantified.. Expression of the TKI targets evaluated was similar between the 2 COF cell lines and the 6 COF tumor biopsies: PDGFR-α and PDGFR-β were detected in neoplastic cells from most COF tumor biopsies (5/6 and 6/6, respectively) and were present in both COF cell lines; KIT and KDR were not detected in any sample. Masitinib and imatinib IC50 values ranged from 7.9-33.4 μM, depending on the specific TKI and cell line tested. The addition of doxorubicin resulted in synergistic cytotoxicity with both TKIs. Anti-PDGFRB siRNA transfection reduced PDGFR-β protein expression by 77% and 67% and reduced cell viability by 24% (p < 0.0001) and 28% (0 = 0.0003) in the two cell lines, respectively.. These results provide rationale for further investigation into the use of TKIs, possibly in combination with doxorubicin, as treatment options for COF.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Benzamides; Cell Line, Tumor; Cell Proliferation; Dog Diseases; Dogs; Doxorubicin; Fibrosarcoma; Imatinib Mesylate; Mouth Neoplasms; Piperidines; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-kit; Pyridines; Receptor, Platelet-Derived Growth Factor alpha; Receptor, Platelet-Derived Growth Factor beta; Thiazoles; Vascular Endothelial Growth Factor Receptor-2

Emerging findings suggested the efficacy of the cannabinoid CB1 receptor antagonist rimonabant (SR141716) in several pathological conditions included tumours. In this study we investigated in vitro the effects of SR141716 on viability and the molecular pathways of methylcholanthrene-induced fibrosarcoma (Meth-A) cells and in vivo its anti-tumour properties in Meth-A-bearing mice. We evaluated in vitro the effect of SR141716 on Meth-A cell viability by trypan blue staining assay. Cell cycle progression and apoptosis were assessed by flow cytometry. Protein expression was investigated by Western blot. The anti-tumour efficacy of SR141716 was evaluated in vivo monitoring weight increase and survival of Meth-A injected mice. SR141716 affects Meth-A cell viability inducing apoptosis and controls cell cycle progression by modulation of the levels of the cell cycle inhibitor p21waf, cyclins E, D1 and NF-kB molecules. Importantly, SR141716 affects AKT/pFoxO1 pathway which promotes cell survival and regulates the cell cycle. The molecular effects observed are accompanied by reduced COX2 expression and induction of the CB1 receptor expression. Finally, SR141716 was able to reduce the tumour size and prolong animal survival, when administered in vivo during tumour growth. Our findings shed light on a novel molecular pathway associated with control of tumour growth by SR141716 and confirm the anti-cancer and anti-inflammatory properties of this drug suggesting its potential applications in the treatment of cancer.

Topics: Animals; Antineoplastic Agents; Apoptosis; Ascites; Cell Cycle; Cell Line, Tumor; Cell Survival; Female; Fibrosarcoma; Gene Expression Regulation, Neoplastic; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Piperidines; Pyrazoles; Receptor, Cannabinoid, CB1; Rimonabant; Sarcoma

Piperine is a major component of black pepper, Piper nigrum Linn, used widely in traditional medicine. Several previous studies reported that piperine possesses various beneficial biological activities including antioxidant, anti-tumor and anti-inflammation properties. In the present study, we investigated the inhibitory effects of piperine on tumor invasion and migration and the possible mechanisms involved using human fibrosarcoma HT-1080 cells. We found that piperine suppresses PMA-enhanced matrix metalloproteinase-9 (MMP-9) expression at the protein, mRNA, and transcriptional levels through the suppression of NF-κB and AP-1 activation without changing the level of tissue inhibitor of metalloproteinase (TIMP)-1. Piperine also inhibits PMA-enhanced membrane-type 1 MMP expression without changing the level of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. Piperine inhibited PMA-induced NF-κB and c-Jun nuclear translocation, which are upstream of PMA-induced MMP-9 expression and invasion. Furthermore, piperine strongly repressed the PMA-induced phosphorylation of ERK, which are dependent on the PKCα pathway. In conclusion, we demonstrated that the anti-invasive effects of piperine may occur through inhibition of PKCα and ERK phosphorylation and reduction of NF-κB and AP-1 activation, leading to down-regulation of MMP-9 expression. Thus, piperine has potential as a potent anti-cancer drug in therapeutic strategies for fibrosarcoma metastasis.

Topics: Alkaloids; Antineoplastic Agents, Phytogenic; Benzodioxoles; Cell Line, Tumor; Cell Movement; Dose-Response Relationship, Drug; Down-Regulation; Fibrosarcoma; Gene Expression Regulation, Enzymologic; Humans; Matrix Metalloproteinase 9; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Neoplasm Invasiveness; NF-kappa B; Phosphorylation; Piperidines; Polyunsaturated Alkamides; Protein Kinase C-alpha; Proto-Oncogene Proteins c-jun; RNA, Messenger; Signal Transduction; Tetradecanoylphorbol Acetate; Time Factors; Transcription Factor AP-1; Transcription, Genetic; Transfection

Metastatic and primary bone cancers are usually accompanied by severe pain that is difficult to manage. In light of the adverse side effects of opioids, manipulation of the endocannabinoid system may provide an effective alternative for the treatment of cancer pain. The present study determined that a local, peripheral increase in the endocannabinoid 2-arachidonoyl glycerol (2-AG) reduced mechanical hyperalgesia evoked by the growth of a fibrosarcoma tumor in and around the calcaneous bone. Intraplantar (ipl) injection of 2-AG attenuated hyperalgesia (ED(50) of 8.2 μg) by activation of peripheral CB2 but not CB1 receptors and had an efficacy comparable to that of morphine. JZL184 (10 μg, ipl), an inhibitor of 2-AG degradation, increased the local level of 2-AG and mimicked the anti-hyperalgesic effect of 2-AG, also through a CB2 receptor-dependent mechanism. These effects were accompanied by an increase in CB2 receptor protein in plantar skin of the tumor-bearing paw as well as an increase in the level of 2-AG. In naïve mice, intraplantar administration of the CB2 receptor antagonist AM630 did not alter responses to mechanical stimuli demonstrating that peripheral CB2 receptor tone does not modulate mechanical sensitivity. These data extend our previous findings with anandamide in the same model and suggest that the peripheral endocannabinoid system is a promising target for the management of cancer pain.

Topics: Animals; Arachidonic Acids; Benzodioxoles; Bone Neoplasms; Calcaneus; Cannabinoid Receptor Antagonists; Dose-Response Relationship, Drug; Endocannabinoids; Fibrosarcoma; Ganglia, Spinal; Glycerides; Hyperalgesia; Male; Mice; Mice, Inbred C3H; Monoacylglycerol Lipases; Piperidines; Polyunsaturated Alkamides; Receptor, Cannabinoid, CB2; Signal Transduction; Skin; Tibial Nerve

Pain associated with cancer and chronic musculoskeletal disorders can be difficult to control. We used murine models of cancer and inflammatory muscle pain to examine whether the cannabinoid receptor agonist WIN55,212-2 reduces hyperalgesia originating in deep tissues. C3H/He mice were anesthetized and implanted with osteolytic NCTC clone 2472 cells into the humeri or injected with 4% carrageenan into the triceps muscles of both forelimbs. At the time of peak hyperalgesia, WIN55,212-2 (1-30mg/kg) or vehicle was administered intraperitoneally and forelimb grip force was measured 0.5-24h later. WIN55,212-2 produced time- and dose-related antihyperalgesia in both models. A 10mg/kg dose of WIN55,212-2 fully reversed carrageenan-evoked muscle hyperalgesia. However, 30mg/kg of WIN55,212-2 attenuated tumor-evoked hyperalgesia only approximately 50%. After controlling for the difference in magnitude of hyperalgesia between the two models, WIN55,212-2 was still more potent at reducing hyperalgesia in the inflammatory model. In the cancer pain model, the antihyperalgesic effect of WIN55,212-2 was partially blocked by pretreatment with the selective CB1 (SR141716A) but not the CB2 (SR144528) receptor antagonist. In contrast, both antagonists blocked antihyperalgesic effects of WIN55,212-2 on carrageenan-evoked muscle hyperalgesia. Catalepsy and loss of motor coordination, known side effects of cannabinoids, did not account for the antihyperalgesia produced by WIN55,212-2. These data show that cannabinoids attenuate deep tissue hyperalgesia produced by both cancer and inflammatory conditions. Interestingly, cannabinoids differentially modulated carrageenan- and tumor-evoked hyperalgesia in terms of potency and receptor subtypes involved suggesting that differences in underlying mechanisms may exist between these two models of deep tissue pain.

Topics: Animals; Benzoxazines; Calcium Channel Blockers; Camphanes; Cannabinoids; Carrageenan; Catalepsy; Disease Models, Animal; Dopamine Antagonists; Dose-Response Relationship, Drug; Drug Interactions; Fibrosarcoma; Haloperidol; Hand Strength; Humerus; Hyperalgesia; Male; Mice; Mice, Inbred C3H; Morpholines; Myositis; Naphthalenes; Neoplasm Transplantation; Neoplasms; Pain; Piperidines; Psychomotor Performance; Pyrazoles; Receptors, Cannabinoid; Receptors, Drug; Rimonabant

Activation of endothelin receptors on the vasculature can produce a variety of responses from potent vasoconstriction to mild vasodilation, depending on the receptor complement within the tissue. To elucidate the potential role of endothelin analogues as tumour blood flow modifiers, we have evaluated the effect of the ET(B) receptor agonist, IRL 1620 ([Suc-(Glu9, Ala(11,15))-ET-1(8-21)]) in CBH/CBi rats bearing an HSN fibrosarcoma. Tissue blood flow and vascular resistance were determined, 20 min following administration of IRL 1620 (bolus intravenous), using the uptake of radiolabelled iodoantipyrine (125I-IAP). Blood flow was unchanged in most tissues. However, at doses > or = 1.0 nmol kg(-1) IRL 1620, blood flow in the brain and heart was increased, whereas in the small intestine it was reduced. Blood flow in the skeletal muscle was reduced at 1.0 nmol kg(-1) only. Tumour blood flow was significantly reduced at 3.0 and 5.0 nmol kg(-1). Vascular resistance was unchanged in most tissues although it was increased in the skeletal muscle at 1.0 nmol kg(-1), in the kidney at 1.0 and 3.0 nmol kg(-1) and in the brain and heart, it was reduced at 5.0 nmol kg(-1) IRL 1620. Vascular resistance was significantly increased in the tumour and the small intestine at doses > or = 1 nmol kg(-1) IRL 1620. Pretreatment of rats with BQ-788, an ET(B) receptor antagonist, selectively attenuated the tumour vascular response to 3 nmol kg(-1) IRL 1620 with no changes observed in the normal tissue responses. Our results demonstrate that the HSN tumour vasculature is selectively responsive to IRL 1620 at doses > 1 nmol kg(-1) compared with the majority of normal tissues with the exception of the small intestine, and that only the tumour response is highly sensitive to BQ-788 antagonism, under the experimental dosing regime investigated. These differences may be exploitable for therapeutic benefit.

Topics: Analysis of Variance; Animals; Antipyrine; Blood Pressure; Endothelins; Fibrosarcoma; Heart Rate; Oligopeptides; Peptide Fragments; Piperidines; Rats; Rats, Inbred Strains; Receptors, Endothelin; Reference Values; Regional Blood Flow; Vascular Resistance

The total synthesis and in vitro activities of a series of chemical inducers of dimerization (CIDs) is described. The use of small-molecule CIDs to control the dimerization of engineered FKBP12-containing fusion proteins has been demonstrated to have broad utility in biological research as well as potential medical applications in gene and cell therapies. The facility and flexibility of preparation make this new class of wholly synthetic compounds exceptionally versatile tools for the study of intracellular signaling events mediated by protein-protein interactions or protein localization. While some congeners possess potency comparable to or better than the first generation natural product-derived CID, FK1012, structure-activity relationships are complex and underscore the need for application-specific compound optimizations.

Topics: Apoptosis; Carboxylic Acids; Dimerization; Fibrosarcoma; Humans; Immunophilins; In Vitro Techniques; Inhibitory Concentration 50; Ligands; Piperidines; Proteins; Structure-Activity Relationship; Tacrolimus Binding Proteins; Tumor Cells, Cultured

Modification of blood flow by endothelin-1 (ET-1) was examined in the s.c. HSN fibrosarcoma and compared to normal tissues of anaesthetised CBH/CBi rats. The ET receptor subtypes involved in the response were investigated using the ET(A) and ET(B) receptor antagonists BQ-610 and BQ-788, respectively. Blood flow and vascular resistance were determined using the uptake of radiolabelled iodo-antipyrine (125I-IAP). BQ-610 or BQ-788 was infused for 30 min prior to blood flow determination. ET-1 was administered 15 min into the infusion time. BQ-610 and BQ-788 infused alone did not modify any vascular parameters. Tumour blood flow increased slightly following ET-1, contrasting with most normal tissues, in which blood flow was reduced. Vascular resistance increased in all tissues, including the tumour. Neither antagonist significantly modified the ET-1-induced changes in tumour blood flow or vascular resistance, whereas in the majority of normal tissues BQ-610 attenuated and BQ-788 potentiated the vascular resonse to ET-1. Our results show that the HSN tumour vasculature is only weakly responsive to ET- 1 and antagonism of its effects by BQ-610 and BQ-788. This contrasts with the majority of normal tissues, in which ET- 1 induces an intense vasoconstriction.

Topics: Animals; Blood Flow Velocity; Blood Pressure; Endothelin Receptor Antagonists; Endothelin-1; Female; Fibrosarcoma; Heart Rate; Hemodynamics; Neoplasms, Experimental; Oligopeptides; Piperidines; Rats; Receptor, Endothelin A; Receptor, Endothelin B; Vascular Resistance

A piperidine phospholipid ((+/-)-2-[hydroxy] [1-octadecyloxycarbonylpiperidin-3-yl]methoxy-phosphinyl] oxy]-N,N,N, trimethylethaniminium hydroxide inner salt, SDZ 62-826) has been prepared that exhibited weak direct cytotoxicity and strong macrophage-induced cytotoxicity in vitro against a variety of murine and one human tumor cell lines. This compound was found to be as effective as ET-18-OCH3 and SRI 62-834, phospholipids with both strong direct and macrophage-induced cytotoxicity, in increasing survivors and reducing tumor volume when given either orally or intravenously in the mouse MethA fibrosarcoma model. These findings suggest that the macrophage-induced cytotoxicity exhibited by ET-18-OCH3 and other phospholipids may play an important role in this tumor model.

Topics: Animals; Antineoplastic Agents; Binding, Competitive; Cell Survival; Fibroblasts; Fibrosarcoma; Humans; Lethal Dose 50; Macrophages; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Neoplasm Transplantation; Phospholipid Ethers; Piperidines; Platelet Activating Factor; Platelet Aggregation Inhibitors; Platelet Membrane Glycoproteins; Receptors, Cell Surface; Receptors, G-Protein-Coupled; Receptors, Platelet-Derived Growth Factor; Sarcoma, Experimental; Tumor Cells, Cultured

As shown in earlier studies, the lodgement of circulating tumour cells in the lungs is reduced by thrombocytopenia in both normal and traumatized rats. Other experiments have shown that thrombocytopenia and antiserotonin treatment with ketanserin, which has a selective effect on 5-HT2 receptors, decrease the hepatic lodgement of intraportally injected tumour cells. The present studies show that treatment with ketanserin also reduces the lodgement of i.v.-injected tumour cells in the lungs in both normal and traumatized rats.

Topics: Animals; Femoral Fractures; Fibrosarcoma; Ketanserin; Lung Neoplasms; Neoplasm Transplantation; Neoplastic Cells, Circulating; Piperidines; Rats; Sarcoma, Experimental; Serotonin Antagonists

The hepatic lodgement of intraportally injected fibrosarcoma cells was analysed with a combination of vital fluorescence microscopic, electron microscopic and isotope techniques in normal, thrombocytopenic and antiserotonin treated (Ketanserin) rats. Ketanserin had no effect on the initial arrest of the tumor cells, as measured 5 min after tumor cell injection, which is in analogy with our previous results on thrombocytopenia. Three hours after injection, the number of lodged tumor cells was significantly reduced by both thrombocytopenia and Ketanserin treatment. Thrombocytopenia was more efficient in reducing tumor cell lodgement than antiserotonin treatment. The in vivo and electron microscopic observations indicated that the reduction of tumor cell lodgement was due to an increased destruction of tumor cells. The similar effects of Ketanserin and thrombocytopenia suggest that serotonin, when released from platelets activated in the presence of tumor cells, increases the survival of fibrosarcoma cells lodged in the liver.

Topics: Animals; Female; Fibrosarcoma; Ketanserin; Liver Neoplasms; Male; Microscopy, Electron; Microscopy, Fluorescence; Neoplasm Transplantation; Neoplastic Cells, Circulating; Phagocytosis; Piperidines; Rats; Sarcoma, Experimental; Serotonin Antagonists; Thrombocytopenia