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2.
Eur Arch Otorhinolaryngol ; 280(1): 307-312, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35867153

ABSTRACT

OBJECTIVES: The aim of this study was to assess safety and efficacy of a non-invasive 2940 nm Er:YAG treatment with SMOOTH mode in reducing snoring in adult patients and to compare its efficacy and safety to sham treatment in a randomized controlled trial setting.  METHODS: 40 primary snoring patients (≥ 18 year, AHI < 15e/h, BMI ≤ 30) were randomized to receive either 3 sessions NightLase or sham laser treatment. The main outcome measures were Snore Outcomes Survey (SOS), the Spouse/Bed Partner Survey (SBPS), a visual analogue snoring scale (bed partner) and a visual analogue pain scale. RESULTS: NightLase was well tolerated, no local anaesthesia was required (mean VAS pain score in NightLase group = 3.0 ± 1.7). No complications occurred. SOS, SBPS and VAS snoring scores improved in the NightLase group (33.7 ± 14.1 to 56.2 ± 16.1) (35.0 ± 17.1 to 61.5 ± 16.4) and (7.9 ± 2.0 to 4.7 ± 2.8) while no changing in the sham group (32.2 ± 14.5 vs 32.1 ± 13.0) (36.7 ± 12.1 vs 34.7 ± 12.7) (8.1 ± 1.7 vs 8.0 ± 1.6), respectively. CONCLUSIONS: NightLase is a safe, minimal invasive treatment that significantly reduced snoring compared to sham treatment.


Subject(s)
Lasers, Solid-State , Adult , Humans , Lasers, Solid-State/therapeutic use , Snoring/surgery , Surveys and Questionnaires , Treatment Outcome
4.
Head Neck ; 36(7): 976-84, 2014 Jul.
Article in English | MEDLINE | ID: mdl-23733258

ABSTRACT

BACKGROUND: The purpose of this phase I/II clinical trial was to test safety and effectiveness of 2 doses of vascular targeting cationic liposomes encapsulating paclitaxel (EndoTAG-1 [ET]) in human head and neck squamous cell carcinoma (HNSCC). METHODS: Patients with nonresectable therapy-refractory HNSCC were recruited for both ET treatment groups (3 or 4 patients per group). In cutaneous metastases, laser Doppler blood flow measurements were conducted during infusions. RESULTS: Only adverse events of grade 1 or 2 according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE version 3.0) - in particular fatigue, chills, and hypertension - occurred. Follow-up tumor volume measurements revealed stable disease in 4 of 5 cases. Reproducible dose-dependent blood flow reductions in skin metastases during ET infusions provide evidence of biological effectiveness. CONCLUSION: Infusions of ET seem to be safe and further phase II and III studies are warranted to prove efficacy in the treatment of HNSCC.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Carcinoma, Squamous Cell/drug therapy , Head and Neck Neoplasms/drug therapy , Paclitaxel/administration & dosage , Aged , Angiogenesis Inhibitors/adverse effects , Carcinoma, Squamous Cell/blood supply , Carcinoma, Squamous Cell/pathology , Drug Delivery Systems , Female , Fibrin Fibrinogen Degradation Products/analysis , Head and Neck Neoplasms/blood supply , Head and Neck Neoplasms/pathology , Humans , Infusions, Intravenous , Laser-Doppler Flowmetry , Leukocyte Count , Liposomes , Male , Middle Aged , Paclitaxel/adverse effects , Platelet Count , Prospective Studies , Skin/blood supply , Tumor Necrosis Factor-alpha/blood
5.
Eur Arch Otorhinolaryngol ; 270(4): 1481-7, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23015197

ABSTRACT

The aim of this first-time-in-human non-randomized dose-escalating prospective phase I clinical trial was to analyze safety of two doses of fluorescent rhodamine-labeled cationic liposomes (LDF01) in head and neck squamous cell carcinoma (HNSCC). Patients had resectable UICC stadium I-IV A HNSCCs. LDF01 was administered before tumor resection under general anesthesia as an intravenous infusion with effective lipid doses of 0.5 or 2 mg/kg b.w., respectively. In addition to clinical monitoring for safety assessment, tumor biopsies were taken during the surgical procedure for fluorescence histological analysis. Eight patients were assigned to the two dose groups. During safety follow-up no clinically relevant adverse events occurred. Fluorescence histology revealed some evidence of favorable selectivity of LDF01 for tumor microvessels in the high-dose group. LDF01 is safe applied as infusion at both tested dose levels. Furthermore, LDF01 can be detected in the vicinity of tumor cells and could be assigned to the microvessel target in individual HNSSC cases. Detailed analysis of targeting properties of LDF01 has to be performed in upcoming clinical phase II trials.


Subject(s)
Carcinoma, Squamous Cell/blood supply , Carcinoma, Squamous Cell/surgery , Drug Delivery Systems/methods , Fluorescent Dyes/administration & dosage , Liposomes/administration & dosage , Microvessels/pathology , Otorhinolaryngologic Neoplasms/blood supply , Otorhinolaryngologic Neoplasms/surgery , Rhodamines/administration & dosage , Aged , Biopsy , Carcinoma, Squamous Cell/pathology , Dose-Response Relationship, Drug , Female , Humans , Infusions, Intravenous , Male , Microscopy, Fluorescence , Middle Aged , Neoplasm Staging , Otorhinolaryngologic Neoplasms/pathology , Prospective Studies
6.
Int J Cancer ; 126(5): 1235-45, 2010 Mar 01.
Article in English | MEDLINE | ID: mdl-19697323

ABSTRACT

Cationic lipid complexed paclitaxel (EndoTAG-1) is a novel vascular targeting agent for the treatment of cancer. Here, the aim was to investigate intratumoral drug distribution after EndoTAG-1 therapy and analyze the impact of EndoTAG-1 scheduling on antitumoral efficacy. The therapeutic effect of EndoTAG-1 in combination with conventional gemcitabine or cisplatin therapy was evaluated in L3.6pl orthotopic pancreatic cancer and a subcutaneous Lewis lung (LLC-1) carcinoma model. Oregon Green paclitaxel encapsulated in cationic liposomes in combination with intravital fluorescence microscopy clearly exhibited delivery of the drug by EndoTAG-1 to the tumor endothelium, whereas Oregon Green paclitaxel dissolved in cremophor displayed an interstitial distribution pattern. The therapeutic efficacy of EndoTAG-1 was critically dependent on the application schedule with best therapeutic results using a metronomic rather than a maximum tolerated dose application sequence. The combination of EndoTAG-1 therapy and cytotoxic chemotherapy significantly enhanced antitumoral efficacy in both tumor models. Interestingly, only EndoTAG-1 in combination with gemcitabine was able to inhibit the incidence of metastasis in pancreatic cancer. In conclusion, vascular targeting tumor therapy by EndoTAG-1 combined with standard small molecular chemotherapy results in markedly enhanced antitumoral efficacy. Therefore, this combination represents a promising novel strategy for clinical cancer therapy.


Subject(s)
Antineoplastic Agents/administration & dosage , Lung Neoplasms/drug therapy , Neovascularization, Pathologic/drug therapy , Paclitaxel/administration & dosage , Pancreatic Neoplasms/drug therapy , Animals , Carcinoma, Lewis Lung , Cisplatin/administration & dosage , Cricetinae , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Drug Administration Schedule , Drug Delivery Systems , Humans , Immunohistochemistry , Lipopeptides , Liposomes , Lung Neoplasms/blood supply , Male , Mice , Pancreatic Neoplasms/blood supply , Gemcitabine
7.
Cancer Biol Ther ; 8(18): 1756-62, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19633422

ABSTRACT

Exposure to static magnetic fields (SMFs) results in a reduced blood flow in tumor vessels as well as in activation and adherence of platelets. Whether this phenomenon may have a significant functional impact on tumors has not been investigated as yet. The aim of our study was to evaluate the effects of prolonged exposure to SMFs on tumor angiogenesis and growth. Experiments were performed in dorsal skinfold chamber preparations of Syrian Golden hamsters bearing syngenic A-Mel-3 melanomas. On 3 d following tumor cell implantation one group of animals was immobilized and exposed to a SMF of 586 mT for three h. Control animals were immobilized for the same duration without SMF exposure. Using in vivo-fluorescence microscopy the field effects on tumor angiogenesis and microcirculation were analyzed for seven days. Tumor growth was assessed by repeated planimetry of the tumor area during the observation period. Exposure to SMFs resulted in a significant retardation of tumor growth ( approximately 30%). Furthermore, histological analysis showed an increased peri- and intratumoral edema in tumors exposed to SMFs. Analysis of microcirculatory parameters revealed a significant reduction of functional vessel density, vessel diameters and red blood cell velocity in tumors after exposure to SMFs compared to control tumors. These changes reflect retarded vessel maturation by antiangiogenesis. The increased edema after SMF exposure indicates an increased tumor microvessel leakiness possibly enhancing drug-uptake. Hence, SMF therapy appears as a promising new anticancer strategy-as an inhibitor of tumor growth and angiogenesis and as a potential sensitizer to chemotherapy.


Subject(s)
Magnetic Field Therapy/methods , Melanoma, Experimental/blood supply , Melanoma, Experimental/therapy , Neovascularization, Pathologic/prevention & control , Animals , Cells, Cultured , Cricetinae , Melanoma, Experimental/pathology , Mesocricetus , Microcirculation , Microscopy, Fluorescence , Tumor Burden
8.
Clin Cancer Res ; 14(14): 4603-11, 2008 Jul 15.
Article in English | MEDLINE | ID: mdl-18628475

ABSTRACT

PURPOSE: Paclitaxel encapsulated in cationic liposomes (EndoTAG-1) is a vascular targeting formulation for the treatment of solid tumors. It triggers intratumoral microthrombosis, causing significant inhibition of tumor perfusion and tumor growth associated with endothelial cell apoptosis. Here, we quantified the effects of repeated EndoTAG-1 therapy on tumor microvascular leakiness with respect to leukocyte-endothelial cell interactions, the targeting property of cationic liposomes, and the therapeutic combination with conventional cisplatin chemotherapy. EXPERIMENTAL DESIGN: Using dorsal skinfold chamber preparations in Syrian Golden hamsters, in vivo fluorescence microscopy experiments were done after repeated EndoTAG-1 treatment of A-Mel-3 tumors. Controls received glucose, paclitaxel alone, or cationic liposomes devoid of paclitaxel. Extravasation of rhodamine-labeled albumin was measured to calculate microvessel permeability, and intratumoral leukocyte-endothelial cell interactions were quantified. Subcutaneous tumor growth was evaluated after combination therapy followed by histologic analysis. RESULTS: Microvascular permeability was significantly increased only after treatment with EndoTAG-1, whereas intratumoral leukocyte-endothelial cell interactions were not affected by any treatment. In separate skinfold chamber experiments, fluorescently labeled cationic liposomes kept their targeting property for tumor endothelial cells after repeated EndoTAG-1 treatment and no signs of extravasation were observed. Subcutaneous A-Mel-3 tumor growth was significantly inhibited by the combination of cisplatin and EndoTAG-1. CONCLUSIONS: These data show that vascular targeting with EndoTAG-1 increases tumor microvessel leakiness probably due to vascular damage. This mechanism is not mediated by inflammatory leukocyte-endothelial cell interactions. Manipulating the blood-tumor barrier by repeated tumor microvessel targeting using EndoTAG-1 can effectively be combined with tumor cell-directed conventional cisplatin chemotherapy.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Capillaries/drug effects , Capillary Permeability/drug effects , Melanoma, Experimental/drug therapy , Neovascularization, Pathologic/drug therapy , Paclitaxel/administration & dosage , Animals , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cations , Cisplatin/administration & dosage , Cricetinae , Liposomes , Male , Melanoma, Experimental/blood supply , Mesocricetus
9.
Cancer Biol Ther ; 7(6): 814-9, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18340115

ABSTRACT

Red blood cell flow in capillaries is reduced during exposure to strong static magnetic fields (SMFs). Intratumoral microcirculation is characterized by tortuous microvessels with chaotic architecture and by irregular, sluggish blood flow with unstable rheology. It was the aim of this study to analyze SMF exposure effects on tumor microcirculation with regard to interactions of corpuscular blood components with tumor microvessel walls. In vivo fluorescence microscopy was performed in A-Mel-3 tumors growing in dorsal skinfold chamber preparations of Syrian Golden hamsters. SMFs with varying field strength (< 600 mT) were generated by changing the distance between a strong NdFeB rod magnet and the tissue region of interest. Short-time exposure above a magnetic flux density of about 150 mT resulted in a significant reduction of red blood cell velocity (vRBC) and segmental blood flow in tumor microvessels. At the maximum strength of 587 mT, a reversible reduction of vRBC (approximately 40%) and of functional vessel densitiy (approximately 15%) was observed. Prolongation of the exposure time from 1 min to up to 3 h resulted in comparable reductions. Microvessel diameters and leukocyte-endothelial cell interactions remained unaffected by SMF exposure. However, in contrast to tumor-free striated muscle controls, exposure at the maximum flux density induced a significant increase in platelet-endothelial cell adherence in a time-dependent manner that was reversible after reducing SMF strength. These reversible changes may have implications for functional measurements of tumor microcirculation by MRI and new therapeutic strategies using strong SMFs.


Subject(s)
Electromagnetic Fields , Microcirculation , Neoplasms/metabolism , Neoplasms/therapy , Platelet Adhesiveness , Angiogenesis Inhibitors/pharmacology , Animals , Capillaries/metabolism , Cricetinae , Leukocytes/cytology , Magnetic Resonance Imaging/methods , Male , Mesocricetus , Muscles/blood supply , Neovascularization, Pathologic , Rheology
10.
Int J Cancer ; 122(2): 452-60, 2008 Jan 15.
Article in English | MEDLINE | ID: mdl-17918179

ABSTRACT

Paclitaxel encapsulated in cationic liposomes (EndoTAG-1) significantly impairs tumor growth by a significant reduction of functional tumor microcirculation and induction of endothelial cell apoptosis. The aim of the study was to analyze whether platelet activation within the tumor microcirculation contributes to the antivascular effects of vascular targeting chemotherapy using EndoTAG-1. In vitro, FACS analysis revealed a significant activation of platelets upon treatment with EndoTAG-1. In vivo, using A-Mel-3 tumors in Syrian Golden hamsters equipped with dorsal skinfold chamber preparations, the contribution of platelets to the antivascular effects of EndoTAG-1 was evaluated by fluorescence and laser-scanning microscopy. Immediately after a single treatment with EndoTAG-1 or cationic liposomes devoid of paclitaxel, an increase of platelet adherence in tumor microvessels was observed. This was accompanied by an acute impairment of the microcirculation within the treated tumors leading to reduced tumor perfusion. After repetitive therapy, an increase of platelet adherence and subsequent tumor microvessel occlusions occurred only after treatment with EndoTAG-1. Comparing to "tumor free" normal tissue controls these microthromboses were tumor selective. Significantly disbalancing the coagulation system within tumors by targeted induction of microthromboses within the tumor microcirculation appears to be an important mechanism of EndoTAG-1 therapy.


Subject(s)
Antineoplastic Agents/pharmacology , Blood Platelets/metabolism , Drug Delivery Systems , Liposomes/chemistry , Paclitaxel/administration & dosage , Animals , Apoptosis , Cricetinae , Endothelial Cells/pathology , Flow Cytometry , Mesocricetus , Microcirculation , Microscopy, Confocal , Microscopy, Fluorescence , Paclitaxel/pharmacology , Platelet Adhesiveness
11.
Microcirculation ; 15(1): 15-26, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17952798

ABSTRACT

Blood flowing in microvessels is one possible site of action of static magnetic fields (SMFs). We evaluated SMF effects on capillary flow of red blood cells (RBCs) in unanesthetized hamsters, using a skinfold chamber technique for intravital fluorescence microscopy. By this approach, capillary RBC velocities (v(RBC)), capillary diameters (D), arteriolar diameters (D(art)), and functional vessel densities (FVD) were measured in striated skin muscle at different magnetic flux densities. Exposure above a threshold level of about 500 mT resulted in a significant (P < 0.001) reduction of v(RBC) in capillaries as compared to the baseline value. At the maximum field strength of 587 mT, v(RBC) was reduced by more than 40%. Flow reduction was reversible when the field strength was decreased below the threshold level. In contrast, mean values determined at different exposure levels for the parameters D, D(art), and FVD did not vary by more than 5%. Blood flow through capillary networks is affected by strong SMFs directed perpendicular to the vessels. Since the influence of SMFs on blood flow in microvessels directed parallel to the field as well as on collateral blood supply could not be studied, our findings should be carefully interpreted with respect to the setting of safety guidelines.


Subject(s)
Electromagnetic Fields , Muscle, Striated/blood supply , Regional Blood Flow/physiology , Regional Blood Flow/radiation effects , Skin/blood supply , Animals , Arterioles/physiology , Arterioles/radiation effects , Capillaries/physiology , Capillaries/radiation effects , Cricetinae , Erythrocytes , Mesocricetus , Microcirculation/physiology , Microcirculation/radiation effects , Microscopy, Fluorescence/instrumentation , Microscopy, Fluorescence/methods , Models, Cardiovascular , Rats
12.
Int J Cancer ; 119(2): 423-31, 2006 Jul 15.
Article in English | MEDLINE | ID: mdl-16477628

ABSTRACT

Anti-angiogenesis is a promising strategy for cancer therapy currently evaluated in clinical trials. The aim of the study was to investigate the effects of an antiangiogenic combination therapy inhibiting alpha(v)-integrins by a c(yclic)RGD-peptide (EMD270179) and blocking VEGFR-2 by SU5416 on tumor angiogenesis and progression in vivo. Experiments were performed in dorsal skinfold chamber preparations of Syrian golden hamsters (60 +/- 5 g) bearing A-Mel-3 tumors. From day 3-10 after tumor-cell implantation, animals (n = 6 per group) were treated by monotherapies using the cRGD-peptide (114 mg/kg/day; i.p.), the VEGFR-2 antagonist (6 mg/kg/day; i.p.) or by the combination of both monotherapies. A control group received only the solvent DMSO. Using intravital microscopy parameters of intratumoral microcirculation were analyzed on day 5, 7 and 10. In separate experiments subcutaneous tumor growth and metastasis formation was evaluated starting therapy on day 0. Functional vessel density was significantly reduced by the combination therapy compared to that by all other groups on day 10. Although intratumoral red blood cell velocity and vessel diameters were less affected, blood flow in vessel segments and the microcirculatory perfusion index were lower after combined therapy compared to controls. In addition, we observed a significantly stronger inhibition of subcutaneous tumor growth and metastasis formation using the combination therapy. These data clearly support the concept of antiangiogenic combination therapy and demonstrate that it may especially be effective when scheduled as an early or prophylactic treatment regimen, thus avoiding angiogenesis-dependent tumor and metastasis initiation or tumor recurrence.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Indoles/pharmacology , Integrin alphaV/drug effects , Neovascularization, Pathologic/prevention & control , Pyrroles/pharmacology , Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors , Animals , Cricetinae , Disease Progression , Male , Mesocricetus , Microcirculation/drug effects , Neoplasm Metastasis/prevention & control , Neoplasm Recurrence, Local/prevention & control
13.
Onkologie ; 28(10): 491-5, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16160398

ABSTRACT

OBJECTIVE: The purpose of this pilot study was to evaluate the feasibility and toxicity of concurrent chemotherapy with vinorelbine and mitomycin C in combination with accelerated radiotherapy (RT) in patients with locally advanced cancer of the head and neck. PATIENTS AND METHODS: Between January 2003 and March 2004, 15 patients with T4/N2-3 squamous cell carcinoma (12/15) and with N3 cervical lymph node metastases of carcinoma of unknown primary (3/15) were treated with chemotherapy and simultaneous accelerated RT. RESULTS: 11 patients completed therapy without interruption or dose reduction. Grade 3-4 acute mucosal toxicity was observed in 9/15 patients, grade 4 hematologic toxicity in 6/15 patients. At a median follow-up of 7.5 months, 2 patients have died of intercurrent disease, 2 patients have experienced local relapse; 5 patients are alive with no evidence of disease at the primary tumor site. DISCUSSION: The described regimen is highly effective, but led to remarkable side effects.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/radiotherapy , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/radiotherapy , Aged , Antibiotics, Antineoplastic/administration & dosage , Antineoplastic Agents, Phytogenic/administration & dosage , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/secondary , Chemotherapy, Adjuvant/methods , Head and Neck Neoplasms/mortality , Humans , Lymphatic Metastasis , Male , Middle Aged , Mitomycin/administration & dosage , Radiotherapy, Adjuvant , Risk Assessment/methods , Risk Factors , Survival Rate , Treatment Outcome , Vinblastine/administration & dosage , Vinblastine/analogs & derivatives , Vinorelbine
14.
MMW Fortschr Med ; 147(9): 26-7, 29-30, 2005 Mar 03.
Article in German | MEDLINE | ID: mdl-15794350

ABSTRACT

A swelling in the neck is a common finding. Underlying causes may be enlarged lymph nodes and cysts, but also benign and malignant tumors. The clinical presentation, however, often gives rise to a fear of a malignant process. In children, more than 95% of such swellings are due to infection. In adults older than 40, however, a malignant tumor may be expected in more that 50% of the cases. Sine early detection is associated with a good prognosis, every mass in the neck must be considered to be potentially malignant. In particular when there is additional difficulty in swallowing or hoarseness, indicative of concomitant involvement of the airways or upper alimentary canal, a further careful diagnostic workup is indicated. Cervical lymph nodes measuring appreciably more than 1 cm in diameter, or additional fever, night sweats or loss of weight must immediately prompt the diagnostic steps necessary to diagnose a malignant lymphoma or carcinoma.


Subject(s)
Head and Neck Neoplasms/diagnosis , Hodgkin Disease/diagnosis , Lymphadenitis/diagnosis , Otolaryngology , Patient Care Team , Respiratory Tract Infections/diagnosis , Adult , Child , Diagnosis, Differential , Humans , Hypopharyngeal Neoplasms/diagnosis , Lymphatic Metastasis
15.
Transplantation ; 79(4): 392-400, 2005 Feb 27.
Article in English | MEDLINE | ID: mdl-15729164

ABSTRACT

BACKGROUND: It is still a matter of investigation how angiogenesis and restoration of gland perfusion determine graft function after free parathyroid autotransplantation. We provide a new animal model allowing simultaneous and repetitive in vivo assessment of angiogenesis and endocrine function of parathyroid transplants. METHODS: Fresh human parathyroid tissue from patients with secondary hyperparathyroidism was grafted into dorsal skinfold chamber preparations of athymic nude mice (CD1-nu; n=8). Equivalent pieces of the same human donor specimens were heat-inactivated and served as control grafts (n=7). RESULTS: In all animals receiving parathyroid transplants, intact human parathyroid hormone levels were detectable by species-specific enzyme-linked immunosorbent assay analysis of plasma samples on day 5 after transplantation and increased by 2.5-fold over the observation period (19 days) in contrast with controls. Plasma Ca levels revealed no differences between the groups. On day 5 after transplantation, intravital fluorescence microscopy revealed murine angiogenic microvessels sprouting along nonperfused human donor vessels, and 1 week later functional microvasculature was established in all parathyroid transplants. Histologic analysis revealed well-vascularized endocrine tissue. In contrast, control grafts were necrotic and partly resorbed; they exhibited no angiogenic activity or well-vascularized fat cells indicating fatty degeneration. In addition, species-specific Western blot analysis revealed vascular endothelial growth factor expression of parathyroid transplants rather than functional vessel density as the functional parameter of angiogenesis determining transplant function in vivo. CONCLUSION: This model may serve to understand mechanisms associated with specific parathyroid transplant angiogenesis and its significance for transplant function to optimize clinical success of autotransplantation in therapy-resistant patients.


Subject(s)
Neovascularization, Physiologic , Parathyroid Glands/transplantation , Parathyroid Hormone/blood , Animals , Calcium/blood , Humans , Male , Mice , Models, Animal , Parathyroid Glands/blood supply , Parathyroid Glands/pathology , Transplantation, Heterologous
16.
Drug Resist Updat ; 7(2): 125-38, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15158768

ABSTRACT

Anti-vascular tumor therapy represents a promising new strategy for cancer treatment. Anti-vascular treatment may be divided in anti-angiogenic and vascular targeting therapy. Whereas anti-angiogenic drugs aim on the inhibition of new vessel formation, vascular targeting compounds are designed to selectively destruct preexisting tumor blood vessels leading to secondary tumor cell death. Both anti-angiogenic drugs and vascular targeting agents have proven effective anti-tumoral activity in numerous preclinical studies over the last decade. In vivo, a combination with anti-vascular tumor therapy enhances the effects of other treatment modalities as chemo- and radiotherapy. Phase I clinical studies revealed a number of well-tolerated candidates. As monotherapy, however, anti-angiogenic treatment lacked efficacy in randomized clinical studies so far. In contrast, combination of anti-angiogenic therapy with chemotherapy was highly effective in an encouraging, large randomized phase III trial on metastatic colorectal cancer. This review will outline recent advances in the preclinical and clinical development of anti-vascular therapy with focus on vascular targeting. Conceptual differences between anti-angiogenic and vascular targeting therapies will be discussed with emphasis on specific problems and pitfalls in the conversion into the clinic.


Subject(s)
Anti-HIV Agents , Neoplasms/drug therapy , Neovascularization, Pathologic/prevention & control , Animals , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/adverse effects , Anti-HIV Agents/therapeutic use , Drug Delivery Systems/methods , Humans , Indoles/therapeutic use , Neoplasms/blood supply , Protein Kinase Inhibitors/therapeutic use , Pyrroles/therapeutic use , Randomized Controlled Trials as Topic , Sunitinib
17.
Int J Cancer ; 110(1): 117-24, 2004 May 20.
Article in English | MEDLINE | ID: mdl-15054876

ABSTRACT

Cationic liposomes have been shown to be internalized selectively by angiogenic tumor endothelial cells after intravenous injection. Therefore, encapsulation of cytotoxic substances in cationic liposomes is a new approach to target tumor vasculature. It was the aim of our study to quantify the effects of paclitaxel encapsulated in cationic liposomes (MBT-0206) on tumor microvasculature and growth in vivo. Experiments were performed in the dorsal skinfold chamber preparation of Syrian Golden hamsters bearing syngeneic A-Mel-3 melanomas. Tumors were treated with intravenous infusion of MBT-0206 (20 mM) resulting in an effective paclitaxel dose of 5 mg/kg body weight (b.w.). Control animals received conventional paclitaxel in Cremophor EL (Taxol(R); 5 mg/kg b.w.), unloaded cationic liposomes (20 mM) or the solvent 5% glucose, respectively. Using intravital microscopy, tumor growth and effects on intratumoral microvasculature were analyzed. Tumor growth was significantly retarded after treatment with MBT-0206 compared to the treatment with paclitaxel. Analysis of intratumoral microcirculation revealed a reduced functional vessel density in tumors after application of liposomal paclitaxel. At the end of the observation time, vessel diameters were significantly smaller in animals treated with paclitaxel encapsulated in cationic liposomes while red blood cell velocity was less affected. This resulted in a significantly reduced blood flow in vessel segments and a reduced microcirculatory perfusion index in these animals. Histochemical TUNEL stain was vessel-associated after treatment with liposomal paclitaxel in contrast to few apoptotic tumor cells in the control groups. Our data demonstrate that encapsulation of paclitaxel in cationic liposomes significantly increased the antitumoral efficacy of the drug. Remarkable microcirculatory changes indicate that encapsulation of paclitaxel in cationic liposomes resulted in a mechanistic switch from tumor cell toxicity to an antivascular therapy.


Subject(s)
Melanoma, Experimental/blood supply , Melanoma, Experimental/drug therapy , Neovascularization, Pathologic/drug therapy , Paclitaxel/administration & dosage , Animals , Cricetinae , Drug Carriers , Erythrocytes/drug effects , In Situ Nick-End Labeling , Liposomes , Male , Melanoma, Experimental/pathology , Mesocricetus , Microcirculation/drug effects , Regional Blood Flow/drug effects
18.
Clin Cancer Res ; 10(6): 2168-78, 2004 Mar 15.
Article in English | MEDLINE | ID: mdl-15041738

ABSTRACT

Hyperthermia increases the efficiency of various chemotherapeutic drugs and is administered as an adjunct to chemotherapy for the treatment of cancer patients. The temperature-dependent effect can be strongly increased by the use of temperature-sensitive liposomes in combination with regional hyperthermia, which specifically releases the entrapped drug in the heated tumor tissue. The novel lipid 1.2-dipalmitoyl-sn-glycero-3-phosphoglyceroglycerol (DPPGOG), which is closely related to the naturally occurring 1.2-dipalmitoyl-sn-glycero-3-phosphoglycerol, in combination with 1.2-dipalmitoyl-sn-glycero-3-phosphocholine and 1.2-distearoyl-sn-glycero-3-phosphocholine provides long-circulating temperature-sensitive liposomes with favorable properties under mildly hyperthermic conditions (41-42 degrees C). DPPGOG facilitates temperature-triggered drug release from these liposomes (diameter, 175 nm) and leads to a substantially prolonged plasma half-life for the encapsulated drug with t(1/2) = 9.6 h in hamsters and t(1/2) = 5.0 h in rats. Quantitative fluorescence microscopy of amelanotic melanoma grown in the transparent dorsal skin fold chamber of hamsters demonstrated a favorable drug accumulation in heated tissue after i.v. application of these liposomes (42 degrees C for 1 h). The mean area under the curve for tissue drug concentration was increased by more than sixfold by application of the new liposomes compared with nonliposomal drug delivery. In summary, we present a new DPPGOG-based liposomal formulation enabling long circulation time combined with fast and efficient drug release under mild hyperthermia. This adds positively to the results with lipid-grafted polyethylenglycol used thus far in temperature sensitive liposomes and widens the possibilities for clinical applications.


Subject(s)
Liposomes/chemistry , Liposomes/pharmacokinetics , 1,2-Dipalmitoylphosphatidylcholine , Animals , Capsules , Cricetinae , Drug Carriers , Half-Life , Liposomes/blood , Molecular Conformation , Phosphatidylcholines
19.
Microvasc Res ; 67(1): 55-63, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14709403

ABSTRACT

Edema formation is the first manifestation of acute pancreatitis. Microcirculatory derangements like leukocyte-endothelial cell interaction and perfusion failure result in enhancement of microvascular permeability to large molecules playing a pivotal role in the progression of the acutely altered pancreatic tissue. Due to the lack of suitable methods the crucial mechanisms of enhanced permeability in vivo are not very well investigated. Sprague-Dawley rats were randomly assigned to three groups: (a) sham operated animals with normal pancreas, (b) the pancreatitis group induced by 60 min temporary occlusion of the arterial supply followed by reperfusion and (c) the histamine group in which the pancreas was superfused with 10(-5)M histamine. The pharmacokinetics of tetramethylrhodamine-labelled BSA in the intravital microscopic images of a capillary network of the pancreas were densitometrically quantified over 20 min. From these data the effective microvascular permeability was calculated taking also into account morphology of microvessels, elimination rate of the tracer from the intravascular space and capillary microhematocrit. In addition macromolecular leakage of gold-labelled BSA was investigated by electron microscopy. Microvascular permeability was 0.10 +/- 0.02 x 10(-7) cm/s, 0.49 +/- 0.04 x 10(-7) cm/s and 1.21 +/- 0.29 x 10(-7) cm/s for control, ischemia and histamine group, respectively (P < 0.05 ischemia, histamine vs. control and ischemia vs. histamine). Electron microscopy revealed albumin extravasation in the last two groups. We established a technique allowing to quantify microvascular permeability in pancreatic tissue by dynamic intravital microscopy being independent of the investigator. This technique enabling accurate pathophysiologic characterisation in terms of edema formation can form the basis for evaluating in the future novel treatment strategies directed against acute pancreatitis.


Subject(s)
Capillary Permeability , Microcirculation/pathology , Microscopy, Fluorescence/methods , Pancreas/blood supply , Pancreatitis/pathology , Animals , Hematocrit , Ischemia , Male , Microscopy, Electron , Models, Statistical , Perfusion , Permeability , Rats , Rats, Sprague-Dawley , Reperfusion Injury , Silver Nitrate/pharmacology , Time Factors
20.
Head Neck ; 25(12): 1004-18, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14648859

ABSTRACT

BACKGROUND: Patients with head and neck cancer are extraordinarily susceptible to depressive traits. Thus, a general screening of these patients at their first admission to the ital is desirable. METHODS: From 1997-2001, 133 patients with head and neck tumors filled in the Self-Rating-Depression-Scale (SDS) at the beginning and end of radiotherapy (ti1/ti2), 6 weeks, and 6 months after radiotherapy (ti3/ti4). RESULTS.: The SDS index increased significantly from 46.44 (ti1) to 48.91(ti2) (p =.025) and then remained stable. The subdomain "somatic-eating-related symptoms" at ti1 was significantly lower than ti2 (p <.001). In contrast to inpatients, outpatients and those with conventional instead of hyperfractionated-accelerated radiotherapy were less impaired by eating-related symptoms. Patients with higher education showed a lower SDS index and cognitive scale. Marital status, tumor stage, histologic grading, and substance abuse had no influence. CONCLUSIONS: Patients with a higher risk of depression should receive long-term monitoring during and after the end of radiotherapy, and prompt intervention strategies should be applied.


Subject(s)
Depression/diagnosis , Depression/etiology , Head and Neck Neoplasms/psychology , Head and Neck Neoplasms/radiotherapy , Adolescent , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Psychological Tests , Radiotherapy/psychology , Risk Factors , Socioeconomic Factors
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