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1.
Drug Discov Today ; 24(10): 2096-2104, 2019 10.
Article in English | MEDLINE | ID: mdl-31228613

ABSTRACT

Low-molecular-weight heparin (LMWH) has attracted increasing attention as a tumor treatment because of its board range of physiological functions. Over the past decade, diverse LMWH derivatives have increased the variety of antitumor strategies available, serving not only as anti-tumor agents, but also as drug delivery platforms. In this review, we introduce the basic strategy for structural modification of LMWH to attenuate its antitumor activity while reducing its risk of bleeding and immune responses, as well as highlighting current applications of LMWH and its derivatives in cancer therapy. We select representative drug delivery systems involving LMWH derivatives and discuss the construction principles and therapeutic effects associated with their use. We also analyze progress made in the development of antitumor combination therapies, in which LMWH has shown synergistic or combined effects with other treatment strategies.


Subject(s)
Antineoplastic Agents/therapeutic use , Drug Design , Drug Therapy, Combination/methods , Heparin, Low-Molecular-Weight/therapeutic use , Heparin, Low-Molecular-Weight/analogs & derivatives , Humans
2.
Cornea ; 36(4): 497-501, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27941385

ABSTRACT

PURPOSE: To compare the therapeutic and preventive effects of topically administered 7-taurocholic acid-conjugated low-molecular-weight heparin (LHT7) and bevacizumab in experimentally induced corneal neovascularization (CoNV). METHODS: CoNV was induced using sutures in the right eyes of 24 mice. To investigate the therapeutic effects, CoNV was allowed to develop for 1 week before treatment. To ascertain the preventive effects, the treatments were applied immediately after the suture. In each experiment, 12 eyes were divided into 3 groups and treated topically using bevacizumab (bevacizumab group), LHT7 (LHT7 group), and normal saline (control group). The treatments were instilled 3 times daily for 2 weeks. The CoNV area was measured before instillation and after 1 and 2 weeks after instillation. RESULTS: In the investigation of therapeutic effects, the CoNV area had decreased significantly 1 week after treatment in the bevacizumab group (1.58-0.75 mm; P = 0.036) and LHT7 group (1.38-0.74 mm; P = 0.018). Two weeks after treatment, the CoNV area was significantly smaller in the bevacizumab groups (0.60 mm; P = 0.005) and LHT7 group (0.64 mm; P = 0.015) than in the control group (1.68 mm), but the bevacizumab group did not differ significantly from the LHT7 group. In the experiment addressing the preventive effects, CoNV was less developed in the bevacizumab group (0.70 mm; P = 0.003) and LHT7 group (0.54 mm; P = 0.003) than in the control group (1.75 mm), and the CoNV area was smaller in the LHT7 group than in the bevacizumab group (P = 0.021). CONCLUSIONS: The effects of LHT7 on CoNV regression are comparable to those of bevacizumab. Topical administration of LHT7 prevents CoNV more effectively than bevacizumab.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Bevacizumab/therapeutic use , Corneal Neovascularization/drug therapy , Disease Models, Animal , Heparin, Low-Molecular-Weight/analogs & derivatives , Taurocholic Acid/analogs & derivatives , Administration, Topical , Animals , Corneal Neovascularization/pathology , Corneal Neovascularization/prevention & control , Heparin, Low-Molecular-Weight/therapeutic use , Mice , Mice, Inbred BALB C , Ophthalmic Solutions , Taurocholic Acid/therapeutic use , Vascular Endothelial Growth Factor A/antagonists & inhibitors
3.
Biomaterials ; 86: 56-67, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26890038

ABSTRACT

Targeting multiple stages in metastatic breast cancer is one of the effective ways to inhibit metastatic progression. To target human metastatic breast cancer as well as improving patient compliance, we developed an orally active low molecular weight heparin (LMWH)-taurocholate conjugated with tetrameric deoxycholic acid, namely LHTD4, which followed by physical complexation with a synthetic bile acid enhancer, DCK. In breast cancer, both transforming growth factor-ß1 (TGF-ß1) and CXCL12 exhibit enhanced metastatic activity during the initiation and progression stages of breast cancer, thus we direct the focus on investigating the antimetastatic effect of LHTD4/DCK complex by targeting TGF-ß1 and CXCL12. Computer simulation study and SPR analysis were performed for the binding confirmation of LHTD4 with TGF-ß1 and CXCL12. We carried out in vitro phosphorylation assays of the consecutive receptors of TGF-ß1 and CXCL12 (TGF-ß1R1 and CXCR4, respectively). Effects of LHTD4 on in vitro cell migration (induced by TGF-ß1) and chemotaxis (mediated by CXCL12) were investigated. The in vivo anti-metastatic effect of LHTD4 was evaluated in an accelerated metastasis model and an orthotopic MDA-MB-231 breast cancer model. The obtained KD values of TGF-ß1 and CXCL12 with LHTD4 were 0.85 and 0.019 µM respectively. The simulation study showed that binding affinities of LHTD4 fragment with either TGF-ß1 or CXCL12 through additional electrostatic interaction was more stable than that of LMWH fragment. In vitro phosphorylation assays of TGF-ß1R1 and CXCR4 showed that the effective inhibition of receptor phosphorylation was observed with the treatment of LHTD4. The expressions of epithelial to mesenchymal transition (EMT) marker proteins such as vimentin and Snail were prevented by LTHD4 treatment in in vitro studies with TGF-ß1 treated MDA-MB-231 cells. Moreover, we observed that LHTD4 negatively regulated the functions of TGF-ß1 and CXCL12 on migration and invasion of breast cancer cell. In several advanced orthotopic and experimental breast cancer metastasis murine models, the treatment with LHTD4 (5 mg/kg daily, p.o.) significantly inhibited metastasis compared to the control. Overall, LHTD4 exhibited anti-metastatic effects by inhibiting TGF-ß1 and CXCL12, and the clinically relevant dose of orally active LHTD4 was found to be effective in preclinical studies without any apparent toxicity.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Deoxycholic Acid/therapeutic use , Heparin, Low-Molecular-Weight/therapeutic use , Neoplasm Metastasis/prevention & control , Taurocholic Acid/therapeutic use , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Breast/drug effects , Breast/metabolism , Breast/pathology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Movement/drug effects , Chemokine CXCL12/metabolism , Deoxycholic Acid/analogs & derivatives , Deoxycholic Acid/pharmacology , Epithelial-Mesenchymal Transition/drug effects , Female , Heparin, Low-Molecular-Weight/analogs & derivatives , Heparin, Low-Molecular-Weight/pharmacology , Humans , Mice, SCID , Molecular Targeted Therapy , Neoplasm Metastasis/pathology , Phosphorylation/drug effects , Taurocholic Acid/analogs & derivatives , Taurocholic Acid/pharmacology , Transforming Growth Factor beta1/metabolism
4.
Org Biomol Chem ; 13(46): 11208-19, 2015 Dec 14.
Article in English | MEDLINE | ID: mdl-26381107

ABSTRACT

d-Glucosamine derivatives bearing latent O4 functionality provide modified H/HS-type disaccharide donors for a final stage capping approach enabling introduction of conjugation-suitable, non-reducing terminal functionality to biologically important glycosaminoglycan oligosaccharides. Application to the synthesis of the first O4-terminus modified synthetic LMWH decasaccharide and an HS-like dodecasaccharide is reported.


Subject(s)
Anticoagulants/chemistry , Disaccharides/chemistry , Glucosamine/analogs & derivatives , Glycosaminoglycans/chemistry , Heparin, Low-Molecular-Weight/analogs & derivatives , Heparin/analogs & derivatives , Oligosaccharides/chemistry , Alkylation , Anticoagulants/chemical synthesis , Crystallography, X-Ray , Disaccharides/chemical synthesis , Glucosamine/chemical synthesis , Glycosaminoglycans/chemical synthesis , Heparin/chemical synthesis , Heparin, Low-Molecular-Weight/chemical synthesis , Models, Molecular , Oligosaccharides/chemical synthesis
5.
Pharm Res ; 32(7): 2318-27, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25585956

ABSTRACT

PURPOSE: To overcome definite limitations of angiogenesis inhibitors such as insufficient therapeutic efficacy as a single drug and resisting or conflicting effect under chronic treatment, it is required to develop a new regimen to improve the therapeutic effect. METHODS: The combination effect of a multi-targeting angiogenesis inhibitor (LHT7) and a selective cyclooxygenase-2 inhibitor (celecoxib) on neovascularization in tumor growth was studied both in vitro and vivo experiments. RESULTS: While hypoxia-mediated COX-2 overexpression and macrophage recruitment were observed at LHT7-treated tumor tissues, it was well-controlled by the combination of celecoxib and LHT7. On the other hand, the in vitro tube formation and the in vivo tumor vessel formation and structure were inhibited by either LHT7 or celecoxib, but the inhibition effect was further enhanced by using them together. However, the combination therapy did not further enhance the inhibitory effect on tumor growth in terms of volume compared to single drug uses, which attributed not to increased cellular apoptosis but to decreased cell proliferation. CONCLUSIONS: COX-2 inhibition could enhance the therapeutic effect of anti-angiogenic drugs both by inhibiting the inflammatory reactions induced by hypoxia and by altering the vascular stabilization that is mediated by an assembly with mural cells.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Celecoxib/pharmacology , Cyclooxygenase 2 Inhibitors/pharmacology , Heparin, Low-Molecular-Weight/analogs & derivatives , Neovascularization, Pathologic/drug therapy , Taurocholic Acid/analogs & derivatives , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/therapeutic use , Animals , Celecoxib/administration & dosage , Celecoxib/chemistry , Celecoxib/therapeutic use , Cell Hypoxia/drug effects , Cyclooxygenase 2/biosynthesis , Cyclooxygenase 2 Inhibitors/administration & dosage , Cyclooxygenase 2 Inhibitors/therapeutic use , Dose-Response Relationship, Drug , Drug Therapy, Combination , Heparin, Low-Molecular-Weight/administration & dosage , Heparin, Low-Molecular-Weight/chemistry , Heparin, Low-Molecular-Weight/pharmacology , Heparin, Low-Molecular-Weight/therapeutic use , Human Umbilical Vein Endothelial Cells , Humans , Male , Mice, Inbred Strains , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Taurocholic Acid/administration & dosage , Taurocholic Acid/chemistry , Taurocholic Acid/pharmacology , Taurocholic Acid/therapeutic use , Xenograft Model Antitumor Assays
6.
J Control Release ; 197: 180-9, 2015 Jan 10.
Article in English | MEDLINE | ID: mdl-25445701

ABSTRACT

Angiogenesis is a key feature of cancer development, thus it is a good target for cancer therapy. However, drugs that have been designed to block angiogenesis mainly capture growth factors in circulation, resulting not only in the transient inhibition of tumor progression but also in producing undesirable side effects. Nanoparticular drug delivery systems, on the other hand, may help overcome such drawbacks and improve the efficacy of anti-angiogenic therapies by altering the biodistribution and pharmacokinetics, improving tumor targeting ability, and reducing side effects. In this light, we propose a new approach of anti-angiogenic therapy that combines strategies of long circulating, passive tumor targeting, and anti-angiogenesis efficacy using a new polyelectrolyte complex system that combines LHT7, a previously developed heparin-based angiogenesis inhibitor, with a protamine to form a self-assembling nanocomplex with a mean diameter of 200nm, which is effective for anti-angiogenesis therapy. At first, LHT7 was modified with polyethylene glycol (PEG). We observed that PEG-LHT7/protamine nanocomplex was stable in buffer and slowly dissociated in plasma (9% dissociation for 24h). Compared to the free form of PEG-LHT7, the mean residence time of PEG-LHT7/protamine nanocomplex was found higher (15.9h) with its increased accumulation in tumor. Most importantly, PEG-LHT7/protamine nanocomplex was diffused and extravasated through the dense collagen matrix of the tumor. Thus, the study describes a successful application of functionalized PEG-LHT/protamine nanocomplex that can inhibit angiogenesis with long circulating, passive targeting, and tumor extravasating ability.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Heparin, Low-Molecular-Weight/analogs & derivatives , Nanostructures/administration & dosage , Neoplasms/drug therapy , Neovascularization, Pathologic/drug therapy , Protamines/administration & dosage , Taurocholic Acid/analogs & derivatives , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/pharmacokinetics , Angiogenesis Inhibitors/toxicity , Animals , Cell Line, Tumor , Heparin, Low-Molecular-Weight/administration & dosage , Heparin, Low-Molecular-Weight/chemistry , Heparin, Low-Molecular-Weight/pharmacokinetics , Heparin, Low-Molecular-Weight/toxicity , Humans , Male , Mice, Inbred C3H , Mice, Nude , Nanostructures/chemistry , Nanostructures/toxicity , Neoplasms/pathology , Neovascularization, Pathologic/pathology , Polyethylene Glycols/chemistry , Protamines/chemistry , Protamines/pharmacokinetics , Protamines/toxicity , Rats, Sprague-Dawley , Taurocholic Acid/administration & dosage , Taurocholic Acid/chemistry , Taurocholic Acid/pharmacokinetics , Taurocholic Acid/toxicity , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
7.
J Appl Toxicol ; 35(1): 104-15, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24532548

ABSTRACT

In our previous studies, taurocholic acid (TA)-conjugated low-molecular-weight heparin derivative (LHT7) has been proven to be a potent anti-angiogenic agent by demonstrated successful blockage capability of vascular endothelial growth factors (VEGF). Preliminary safety evaluations were conducted based on its mechanism of action and chemical behavior. For this purpose, acute toxicity study, and hematological and serological evaluations were carried out. Additionally, in order to evaluate mechanism-related side effects, both blood pressure and the occurrence of proteinuria were measured using a treatment regime of multiple high doses of LHT7 in a biodistribution study. LD50 values for LHT7 in female and male mice were 56.9 and 64.7 mg kg(-1) doses, respectively. There were no vital fluctuations in the serological and hematological parameters, except for the elevated levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) at 100 and 200 mg kg(-1) doses of LHT7, representing vital changes in the liver function. Moreover, the results of mechanism-related studies showed that blood pressure at 50 mg kg(-1) did not change but showed elevated levels of protein in urine. In the biodistribution study, a slight accumulation of LHT7 in the kidney and the liver were observed at the 50 mg kg(-1) repeated dose owing to the presence of bile acid. No fatal damage was observed in this study; most observations were related to the chemical composition or the mechanism of action of the material.


Subject(s)
Angiogenesis Inhibitors/toxicity , Heparin, Low-Molecular-Weight/analogs & derivatives , Taurocholic Acid/analogs & derivatives , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Angiogenesis Inhibitors/pharmacokinetics , Animals , Blood Pressure/drug effects , Body Weight/drug effects , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Female , Heparin, Low-Molecular-Weight/pharmacokinetics , Heparin, Low-Molecular-Weight/toxicity , Kidney/drug effects , Kidney/metabolism , Lethal Dose 50 , Liver/drug effects , Liver/metabolism , Liver Function Tests , Male , Mice, Inbred ICR , Molecular Structure , Organ Size/drug effects , Rats, Sprague-Dawley , Taurocholic Acid/pharmacokinetics , Taurocholic Acid/toxicity , Tissue Distribution , Toxicity Tests, Acute
8.
Biomaterials ; 37: 271-8, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25453957

ABSTRACT

Despite the therapeutic benefits of the angiogenesis inhibitors shown in the clinics, they have encountered an unexpected limitation by the occurrence of acquired resistance. Although the mechanism of the resistance is not clear so far, the upregulation of alternative angiogenic pathways and stabilization of endothelium by mural cells were reported to be responsible. Therefore, blocking multiple angiogenic pathways that are crucial in tumor angiogenesis has been highlighted to overcome such limitations. To develop an angiogenesis inhibitor that could block multiple angiogenic factors, heparin is an excellent lead compound since wide array of angiogenic factors are heparin-binding proteins. In previous study, we reported a heparin-derived angiogenesis inhibitor, LHT7, as a potent angiogenesis inhibitor and showed that it blocked VEGF signaling pathway. Here we show that LHT7 could block the fibroblast growth factor 2 (FGF2) and platelet-derived growth factor B (PDGF-B) in addition to VEGF. Simultaneous blockade of these angiogenic factors resulted in inhibition of multiple stages of the angiogenic process, including initial angiogenic response to maturation of the endothelium by pericyte coverage in vitro. In addition, the treatment of LHT7 in vivo did not show any sign of vascular normalization and directly led to decreased blood perfusion throughout the tumor. Our findings show that LHT7 could effectively inhibit tumor angiogenesis by blocking multiple stages of the angiogenesis, and could potentially be used to overcome the resistance.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Fibroblast Growth Factor 2/metabolism , Heparin, Low-Molecular-Weight/analogs & derivatives , Neovascularization, Pathologic/drug therapy , Neovascularization, Pathologic/metabolism , Proto-Oncogene Proteins c-sis/metabolism , Taurocholic Acid/analogs & derivatives , Vascular Endothelial Growth Factor A/metabolism , Angiogenesis Inhibitors/therapeutic use , Animals , Cell Line , Chemotaxis/drug effects , Coculture Techniques , Collagen/metabolism , Contrast Media , Drug Combinations , Endothelium, Vascular/drug effects , Female , Heparin, Low-Molecular-Weight/pharmacology , Heparin, Low-Molecular-Weight/therapeutic use , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/drug effects , Humans , Kinetics , Laminin/metabolism , Magnetic Resonance Imaging , Male , Mice, Inbred BALB C , Neoplasms/blood supply , Pericytes/cytology , Pericytes/drug effects , Proteoglycans/metabolism , Signal Transduction/drug effects , Taurocholic Acid/pharmacology , Taurocholic Acid/therapeutic use
9.
Anticancer Drugs ; 25(9): 1061-71, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25003253

ABSTRACT

To achieve a clinically rational regimen for cancer chemoprevention with improved efficacy and safety, the combination effect of celecoxib and newly developed oral angiogenesis inhibitor, LHD4, on chemoprevention was evaluated. The chemopreventive effects of celecoxib, LHD4, and the combination of celecoxib and LHD4 were evaluated in a murine colorectal carcinogenesis model. After 17 experimental weeks, mouse colon tissues were collected and examined in terms of polyp volume and degree of carcinogenesis, inflammation, and angiogenesis. Mice in the celecoxib-treated or LHD4-treated groups had total polyp volumes of 47.0±9.7 and 120.1±45.2 mm, respectively, which represented decreases of 65.6 and 22.3% from the control (154.5±33.5 mm). However, the polyp volume in the combination group was 22.8±9.3 mm, a decrease of 85.2% from the control. In the comparison of carcinogenesis, the percentage of normal tissue (i.e. excluding proliferative tissue) was found to be 40.6% in the control, 51.7% in the celecoxib, 56.9% in the LHD4, and 81.7% in the combination group. In accordance with attenuated carcinogenesis, both inflammation and angiogenesis were also well controlled. Together, these results suggest that the combinatory use of celecoxib and a newly developed oral heparin conjugate could be a promising regimen for chemoprevention by intervening in both inflammation and angiogenesis.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Anticarcinogenic Agents/therapeutic use , Carcinogenesis/drug effects , Colorectal Neoplasms/prevention & control , Cyclooxygenase Inhibitors/therapeutic use , Deoxycholic Acid/analogs & derivatives , Heparin, Low-Molecular-Weight/analogs & derivatives , Pyrazoles/therapeutic use , Sulfonamides/therapeutic use , Administration, Oral , Animals , Azoxymethane , Carcinogenesis/chemically induced , Celecoxib , Colon/blood supply , Colon/pathology , Colonic Polyps/chemically induced , Colonic Polyps/pathology , Colonic Polyps/prevention & control , Colorectal Neoplasms/chemically induced , Colorectal Neoplasms/pathology , Deoxycholic Acid/therapeutic use , Dextran Sulfate , Drug Therapy, Combination , Heparin, Low-Molecular-Weight/therapeutic use , Inflammation/chemically induced , Inflammation/prevention & control , Male , Mice, Inbred ICR , Neovascularization, Pathologic/chemically induced , Neovascularization, Pathologic/prevention & control , Tumor Burden
10.
J Control Release ; 189: 80-9, 2014 Sep 10.
Article in English | MEDLINE | ID: mdl-24973719

ABSTRACT

Here, we report reduced graphene oxide (rGO) nanosheets coated with an anti-angiogenic anticancer taurocholate derivative of low-molecular-weight heparin (LHT7) as a tumor-targeting nanodelivery platform for anticancer drugs. Surface coating of LHT7 onto rGO was confirmed using fluorescein isothiocyanate-labeled LHT7, monitored as fluorescence quenching due to associated rGO. Unlike plain rGO, LHT7-coated rGO (LHT-rGO) nanosheets maintained a stable dispersion under physiological conditions for at least 24h. Moreover, LHT-rGO provided greater loading capacity for doxorubicin (Dox) compared with uncoated rGO nanosheets. Following intravenous administration into KB tumor-bearing mice, in vivo tumor accumulation of LHT-rGO/Dox was 7-fold higher than that of rGO/Dox 24h post dosing. In tumor tissues, LHT-rGO/Dox was shown to localize not to the tumor vasculature, but rather to tumor cells. Intravenously administered LHT-rGO/Dox showed the greatest anti-tumor effect in KB-bearing mice, reducing tumor volume by 92.5%±3.1% compared to the untreated group 25days after tumor inoculation. TUNEL assays revealed that the population of apoptotic cells was highest in the group treated with LHT-rGO/Dox. Taken together, our results demonstrate that LHT-rGO nanosheets confer improved dispersion stability, tumor distribution and in vivo antitumor effects, and may be further developed as a potential active nanoplatform of various anticancer drugs.


Subject(s)
Antineoplastic Agents/administration & dosage , Doxorubicin/administration & dosage , Drug Carriers/administration & dosage , Graphite/administration & dosage , Heparin, Low-Molecular-Weight/analogs & derivatives , Nanostructures/administration & dosage , Taurocholic Acid/analogs & derivatives , Adsorption , Animals , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Doxorubicin/chemistry , Drug Carriers/chemistry , Drug Stability , Female , Graphite/chemistry , Heparin, Low-Molecular-Weight/administration & dosage , Heparin, Low-Molecular-Weight/chemistry , Humans , Mice, Inbred BALB C , Mice, Nude , Nanostructures/chemistry , Neoplasms/drug therapy , Neoplasms/pathology , Oxidation-Reduction , Taurocholic Acid/administration & dosage , Taurocholic Acid/chemistry , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
11.
Biomaterials ; 35(24): 6543-52, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24816287

ABSTRACT

Angiogenesis, the formation of new blood vessels, plays a pivotal role in tumor progression and for this reason angiogenesis inhibitors are an important class of therapeutics for cancer treatment. Heparin-based angiogenesis inhibitors have been newly developed as one of such classes of therapeutics and possess a great promise in the clinical context. Taurocholate conjugated low molecular weight heparin derivative (LHT7) has been proven to be a potent, multi-targeting angiogenesis inhibitor against broad-spectrum angiogenic tumors. However, major limitations of LHT7 are its poor oral bioavailability, short half-life, and frequent parenteral dosing schedule. Addressing these issues, we have developed an oral formulation of LHT7 by chemically conjugating LHT7 with a tetrameric deoxycholic acid named LHTD4, and then physically complexing it with deoxycholylethylamine (DCK). The resulting LHTD4/DCK complex showed significantly enhanced oral bioavailability (34.3 ± 2.89%) and prolonged the mean residence time (7.5 ± 0.5 h). The LHTD4/DCK complex was mostly absorbed in the intestine by transcellular pathway via its interaction with apical sodium bile acid transporter. In vitro, the VEGF-induced sprouting of endothelial spheroids was significantly blocked by LHTD4. LHTD4/DCK complex significantly regressed the total vessel fractions of tumor (77.2 ± 3.9%), as analyzed by X-ray microCT angiography, thereby inhibiting tumor growth in vivo. Using the oral route of administration, we showed that LHTD4/DCK complex could be effective and chronically administered as angiogenesis inhibitor.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Deoxycholic Acid/pharmacology , Heparin/pharmacology , Administration, Oral , Angiogenesis Inhibitors/blood , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/pharmacokinetics , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Biological Availability , Caco-2 Cells , Cell Proliferation/drug effects , Deoxycholic Acid/chemistry , Heparin/chemistry , Heparin, Low-Molecular-Weight/analogs & derivatives , Heparin, Low-Molecular-Weight/chemical synthesis , Heparin, Low-Molecular-Weight/chemistry , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Intestinal Absorption/drug effects , Intestines/drug effects , Intestines/physiology , Male , Neoplasms/pathology , Neovascularization, Physiologic/drug effects , Oxidation-Reduction , Rats, Sprague-Dawley , Spheroids, Cellular/cytology , Spheroids, Cellular/drug effects , Spheroids, Cellular/metabolism , Taurocholic Acid/analogs & derivatives , Taurocholic Acid/chemical synthesis , Taurocholic Acid/chemistry
12.
J Control Release ; 195: 155-61, 2014 Dec 10.
Article in English | MEDLINE | ID: mdl-24862320

ABSTRACT

Thrombogenesis is a major cause of morbidity and mortality in cancer patients. Prophylaxis with low-molecular-weight heparin (LMWH) is recommended for cancer patients, but requires non-parenteral delivery methods for long-term treatments. In this study, we sought to generate a new oligomeric-bile acid conjugate of LMWH that can be used for oral delivery. We first synthesized a tetramer of deoxycholic acid (tetraDOCA), which was site-specifically conjugated at the end saccharide of LMWH. When LMWH-tetraDOCA conjugate (LHe-tetraD) was orally administered at a dose of 5 mg/kg in ICR mice, the maximum anti-factor Xa level was increased up to 0.62±0.05 IU/mL without any evidence of liver toxicity, gastrointestinal damage, or thrombocytopenia. The cancer-associated thrombosis was induced in tumor-bearing mice by local heat application, and the fibrin deposition in tumors was evaluated. The oral administration of LHe-tetraD (either a single dose or multiple daily doses for up to 10 days) in mice substantially abolished the coagulation-dependent tropism of fibrinogen in the heated tumors and significantly decreased hemorrhage, compared to the mice treated with saline or subcutaneous injection of LMWH. Thus, the anticoagulation effect of oral LHe-tetraD invokes the benefits of oral delivery and promises to provide an effective and convenient treatment for cancer patients at risk of thrombosis.


Subject(s)
Anticoagulants/administration & dosage , Deoxycholic Acid/analogs & derivatives , Heparin, Low-Molecular-Weight/analogs & derivatives , Thrombosis/prevention & control , Administration, Oral , Animals , Anticoagulants/blood , Anticoagulants/pharmacokinetics , Deoxycholic Acid/administration & dosage , Deoxycholic Acid/blood , Deoxycholic Acid/pharmacokinetics , Factor Xa/metabolism , Fibrinogen/metabolism , Heparin Antagonists/pharmacology , Heparin, Low-Molecular-Weight/administration & dosage , Heparin, Low-Molecular-Weight/blood , Heparin, Low-Molecular-Weight/pharmacokinetics , Humans , Hyperthermia, Induced/adverse effects , Male , Mice, Inbred ICR , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/therapy , Protamines/pharmacology , Rats, Sprague-Dawley , Thrombosis/metabolism
13.
Int J Hematol ; 97(4): 491-7, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23456264

ABSTRACT

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired stem cell disorder characterized by intravascular hemolysis and thrombosis. The most serious complication is thrombosis, the risk of which is augmented by the hyper-coagulable state that occurs during pregnancy; despite this risk, however, young female PNH patients often desire to have a baby. We recently experienced two successful deliveries in PNH patients, who were treated with anticoagulant therapy during their pregnancies. Meanwhile, given the potential benefit of eculizumab (Soliris), a humanized monoclonal antibody against C5, in reducing thrombosis and hemolysis, it represents a promising therapeutic option for the treatment of pregnant PNH patients in combination with, or in replacement of, anticoagulant therapy.


Subject(s)
Anticoagulants/therapeutic use , Hemoglobinuria, Paroxysmal/drug therapy , Adult , Antibodies, Monoclonal, Humanized/therapeutic use , Female , Hemoglobinuria, Paroxysmal/diagnosis , Heparin, Low-Molecular-Weight/analogs & derivatives , Heparin, Low-Molecular-Weight/therapeutic use , Humans , Pregnancy , Pregnancy Outcome , Treatment Outcome
14.
Pulm Pharmacol Ther ; 26(2): 296-304, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23280431

ABSTRACT

No molecule has been found to be effective against emphysema to date primarily because of its complex pathogenesis that involves elastolysis, oxidation and inflammation. We here describe novel unsulfated or sulfated low molecular weight lignins (LMWLs) chemo-enzymatically prepared from 4-hydroxycinnamic acids monomers, as the first potent triple-action inhibitors of neutrophil elastase, oxidation and inflammation. The inhibitory potencies of three different cinnamic acid-based LMWLs were determined in vitro using chromogenic substrate hydrolysis assays, radical scavenging and lung cellular oxidative biomarker reduced glutathione (rGSH) assays, and lung cellular inflammatory biomarker NFκB and IL-8 assays, respectively. Each LWML uniquely displayed triple-action inhibition, among which CDSO3, a sulfated caffeic acid-based LMWL, was most potent. The half-maximal anti-human neutrophil elastase (HNE) potency of CDSO3 was 0.43 µM. This high potency arose from lignin-like oligomerization, which was further potentiated by 6.6-fold due to sulfation. Mechanistically, this elastase inhibition was of mixed-type, time-dependent and more selective to positively charged elastases. The half-maximal anti-oxidative potency of CDSO3 was 3.52 µM, 4.8-fold potentiated from that of the monomer, caffeic acid (CA). In contrast, the half-maximal inhibitory potency to TNFα-induced inflammation was 5-10 µM, despite no activity with the monomer. More intriguingly, this anti-inflammatory activity was essentially identical with different stimuli, okadaic acid and hydrogen peroxide (H(2)O(2)), which implied that CDSO3 acts directly on inflammatory cascades within the cells. Overall, oligomerization and sulfation produced or significantly potentiated the activity, in comparison to the monomer. Thus, sulfated and unsulfated LMWLs are novel non-peptidic 2.8-4.1 kDa macromolecules that exhibit for the first time potent triple inhibitory activity against elastase, oxidation and inflammation, the three major pathogenic mechanisms known to cause emphysema.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Emphysema/drug therapy , Lignin/pharmacology , Proteinase Inhibitory Proteins, Secretory/pharmacology , Heparin, Low-Molecular-Weight/analogs & derivatives , Humans , Interleukin-8/metabolism , Molecular Weight , NF-kappa B/metabolism
15.
Biomaterials ; 34(8): 2077-86, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23245333

ABSTRACT

Various angiogenesis inhibitors and apoptosis-targeting agents have been therapeutically applied in preclinical cancer models, some of which have been tested in clinical trials. In a previous study, we demonstrated that LHT7, a low molecular weight heparin (LMWH)-taurocholate conjugate, has strong antiangiogenic and tumor-suppressive activity and diminished anticoagulant properties. In this study, we developed LHT7-ApoPep-1, an apoptosis-homing peptide-conjugated variant of LHT7. LHT7-ApoPep-1 exhibited antiangiogenic activity in endothelial cell tube-formation assays and apoptotic cell-targeting ability in tumor cell binding assays; it also showed little toxicity toward healthy cells. Administration of LHT7-ApoPep-1 in mouse xenograft models of breast carcinoma delayed tumor growth compared to LHT7-only, and histological evaluations revealed decreased vessel formation and increased apoptotic area in tumor tissues. Moreover, an examination of LHT7-ApoPep-1-Cy7.5 localization within the body using in vivo live imaging showed accumulation at the tumor site of tumor-bearing mice, with a more prolonged circulation time and enhanced intensity compared to LHT7-Cy7.5. Inspection of the tumor microenvironment revealed that Cy5.5-labeled LHT7-ApoPep-1 was located on and near CD31-positive vessels in tumor tissue. We conclude that LHT7-ApoPep-1 has antiangiogenic and apoptosis-targeting properties and exerts antitumor effects by suppressing tumor vessel growth and homing to apoptotic cells within the tumor.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Heparin, Low-Molecular-Weight/analogs & derivatives , Peptides/pharmacology , Taurocholic Acid/analogs & derivatives , Amino Acid Sequence , Angiogenesis Inhibitors/pharmacology , Animals , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Heparin, Low-Molecular-Weight/pharmacology , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/drug effects , Humans , Mice , Mice, Nude , Molecular Sequence Data , Neovascularization, Physiologic/drug effects , Peptides/chemistry , Protein Binding/drug effects , Taurocholic Acid/pharmacology , Tissue Distribution/drug effects , Xenograft Model Antitumor Assays
16.
J Control Release ; 164(1): 8-16, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-23063549

ABSTRACT

LMWH-taurocholate derivative (LHT7) has been reported as a novel angiogenesis inhibitor, due to its ability to bind to several kinds of growth factors, which play critical roles in tumor angiogenesis. In this study, we have highlighted the enhanced antiangiogenic activity of LHT7, by using cyclic RGDyk (cRGD), a targeting moiety that was chemically conjugated to LHT7 via amide bond. The SPR study revealed that cRGD-LHT7 bound to α(v)ß(3) integrin as strongly as cRGD, and it bound to VEGF as strongly as LHT7. Importantly, in vitro anti-angiogenesis studies revealed that cRGD-LHT7 had a significant inhibition effect on HUVEC tubular formation. Finally, cRGD-LHT7 showed a greater inhibitory efficiency on the tumor growth in the U87MG xenograft model than the original LHT7, which was owed to its ability to target the tumor cells. All of these findings demonstrated that cRGD-LHT7 targeted α(v)ß(3) integrin-positive cancer cells and endothelial cells, resulting in a greater anti-angiogenesis effect on the solid tumors.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Heparin, Low-Molecular-Weight/analogs & derivatives , Peptides, Cyclic/chemistry , Taurocholic Acid/analogs & derivatives , Angiogenesis Inhibitors/chemical synthesis , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/therapeutic use , Animals , Cell Line, Tumor , Cell Survival/drug effects , Heparin, Low-Molecular-Weight/chemical synthesis , Heparin, Low-Molecular-Weight/chemistry , Heparin, Low-Molecular-Weight/pharmacology , Heparin, Low-Molecular-Weight/therapeutic use , Human Umbilical Vein Endothelial Cells , Humans , Integrin alphaVbeta3/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Microscopy, Confocal , Microtubules/drug effects , Microtubules/ultrastructure , Molecular Structure , Protein Binding , Taurocholic Acid/chemical synthesis , Taurocholic Acid/chemistry , Taurocholic Acid/pharmacology , Taurocholic Acid/therapeutic use , Xenograft Model Antitumor Assays
17.
Biochem Biophys Res Commun ; 413(2): 348-52, 2011 Sep 23.
Article in English | MEDLINE | ID: mdl-21893043

ABSTRACT

Sulfated, low molecular weight lignins (LMWLs), designed recently as macromolecular mimetics of the low molecular weight heparins (LMWHs), were found to exhibit a novel allosteric mechanism of inhibition of human thrombin, factor Xa and plasmin, which translates into potent human blood anticoagulation potential. To identify the site of binding of sulfated LMWLs, a panel of site-directed thrombin mutants was studied. Substitution of alanine for Arg(93) or Arg(175) induced a 7-8-fold decrease in inhibition potency, while Arg(165)Ala, Lys(169)Ala, Arg(173)Ala and Arg(233)Ala thrombin mutants displayed a 2-4-fold decrease. Other exosite 2 residues including those that play an important role in heparin binding, such as Arg(101), Lys(235), Lys(236) and Lys(240), did not induce any deficiency in sulfated LMWL activity. Thrombin mutants with multiple alanine substitution of basic residues showed a progressively greater defect in inhibition potency. Comparison of thrombin, factor Xa, factor IXa and factor VIIa primary sequences reiterated Arg(93) and Arg(175) as residues likely to be targeted by sulfated LMWLs. The identification of a novel site on thrombin with capability of allosteric modulation is expected to greatly assist the design of new regulators based on the sulfated LMWL scaffold.


Subject(s)
Heparin, Low-Molecular-Weight/analogs & derivatives , Lignin/chemistry , Sulfates/chemistry , Thrombin/chemistry , Amino Acid Substitution , Binding Sites/genetics , Crystallography, X-Ray , Heparin, Low-Molecular-Weight/chemistry , Humans , Molecular Weight , Mutagenesis, Site-Directed , Thrombin/genetics
20.
J Control Release ; 148(3): 317-26, 2010 Dec 20.
Article in English | MEDLINE | ID: mdl-20869408

ABSTRACT

Heparin, an anticoagulant that is widely used clinically, is also known to bind to several kinds of proteins through electrostatic interactions because of its polyanionic character. These interactions are mediated by the physicochemical properties of heparin such as sequence composition, sulfation patterns, charge distribution, overall charge density, and molecular size. Although this electrostatic character mediates its binding to many proteins related with tumor progression, thereby providing its antiangiogenic property, the administration of heparin for treating cancer is limited in clinical applications due to several drawbacks, such as its low oral absorption, unsatisfactory therapeutic effects, and strong anticoagulant activity which induces hemorrhaging. Here, we evaluated novel, orally active, low molecular weight heparin (LMWH) derivatives (LHD) conjugated with deoxycholic acid (DOCA) that show reduced anticoagulant activity and enhanced antiangiogenic activity. The chemical conjugate of LMWH and DOCA was synthesized by conjugating the amine group of N-deoxycholylethylamine (EtDOCA) with the carboxylic groups of heparin at various DOCA conjugation ratios. The LMWH-DOCA conjugate series (LHD1, LHD1.5, LHD2, and LHD4) were further formulated with poloxamer 407 as a solubilizer for oral administration. An in vitro endothelial tubular formation and in vivo Matrigel plug assay were performed to verify the antiangiogenic potential of LHD. Finally, we evaluated tumor growth inhibition of oral LHD administration in a SCC7 model as well as in A549 human cancer cell lines in a mouse xenograft model. Increasing DOCA conjugation ratios showed decreased anticoagulant activity, eventually to zero. LHD could block angiogenesis in the tubular formation assay and the Matrigel plug assay. In particular, oral administration of LHD4, which has 4 molecules of DOCA per mole of LMWH, inhibited tumor growth in SCC7 mice model as well as A549 mice xenograft model. LHD4 was orally absorbable, showed minimal anticoagulant activity and inhibits tumor growth via antiangiogenesis. These findings demonstrate the therapeutic potential of LHD4 as a new oral anti-cancer drug.


Subject(s)
Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/therapeutic use , Anticoagulants/chemistry , Anticoagulants/therapeutic use , Deoxycholic Acid/analogs & derivatives , Heparin, Low-Molecular-Weight/analogs & derivatives , Neoplasms/drug therapy , Administration, Oral , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/pharmacology , Animals , Anticoagulants/administration & dosage , Anticoagulants/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Deoxycholic Acid/administration & dosage , Deoxycholic Acid/chemistry , Deoxycholic Acid/pharmacology , Deoxycholic Acid/therapeutic use , Heparin, Low-Molecular-Weight/administration & dosage , Heparin, Low-Molecular-Weight/chemistry , Heparin, Low-Molecular-Weight/pharmacology , Heparin, Low-Molecular-Weight/therapeutic use , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Nude , Neoplasms/pathology , Solubility
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