955 resultados para targeted alpha therapy


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Terbium-149 is among the most interesting therapeutic nuclides for medical applications. It decays by emission of short-range α-particles (Eα = 3.967 MeV) with a half-life of 4.12 h. The goal of this study was to investigate the anticancer efficacy of a 149Tb-labeled DOTA-folate conjugate (cm09) using folate receptor (FR)-positive cancer cells in vitro and in tumor-bearing mice. 149Tb was produced at the ISOLDE facility at CERN. Radiolabeling of cm09 with purified 149Tb resulted in a specific activity of ~1.2 MBq/nmol. In vitro assays performed with 149Tb-cm09 revealed a reduced KB cell viability in a FR-specific and activity concentration-dependent manner. Tumor-bearing mice were injected with saline only (group A) or with 149Tb-cm09 (group B: 2.2 MBq; group C: 3.0 MBq). A significant tumor growth delay was found in treated animals resulting in an increased average survival time of mice which received 149Tb-cm09 (B: 30.5 d; C: 43 d) compared to untreated controls (A: 21 d). Analysis of blood parameters revealed no signs of acute toxicity to the kidneys or liver in treated mice over the time of investigation. These results demonstrated the potential of folate-based α-radionuclide therapy in tumor-bearing mice.

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Functionally critically located gliomas represent a challenging subgroup of intrinsic brain neoplasms. Standard therapeutic recommendations often cannot be applied, because radical treatment and preservation of neurological function are contrary goals. The successful targeting of gliomas with locally injected beta radiation-emitting (90)Y-DOTAGA-substance P has been shown previously. However, in critically located tumours, the mean tissue range of 5 mm of (90)Y may seriously damage adjacent brain areas. In contrast, the alpha radiation-emitting radionuclide (213)Bi with a mean tissue range of 81 microm may have a more favourable toxicity profile. Therefore, we evaluated locally injected (213)Bi-DOTA-substance P in patients with critically located gliomas as the primary therapeutic modality.

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Molekyylimarkkerit ja pitkäaikainen alfainterferonihoito munuaissyövässä Munuaissyöpäpotilaiden viiden vuoden elossaololuku on noin 50 %. Aikaisempien tutkimuksien mukaan viiden vuoden elossaololuku metastasoituneessa munuaissyövässä on 3-16 %, kun käytettiin alfainterferonia sisältävää hoitoa. Tyypillisesti alfainterferonia on käytetty vähemmäin kuin 6 kuukautta. Avoimia kysymyksiä ovat alfainterferonin optimaalinen hoitoannos ja hoidon kesto yksin tai yhdessä uusien täsmähoitojen kanssa. Tärkeimmät tavoitteet olivat tutkia 1) jaksotetun pitkäaikaisen alfainterferonihoidon tehoa ja siedettävyyttä metastasoituneessa munuaissyövässä ja 2) p53-, Ki-67- ja COX-2-proteiinituotannon ennusteellista merkitystä munuaissyövässä. Tutkimuksessa 117 metastasoituneelle munuaissyöpää sairastaneelle potilaalle etsittiin yksilöllinen hänen sietämänsä maksimaalinen hoitoannos rekombinanttia alfa2a-interferonia (Roferon-ATM). Hoitoa pyrittiin jatkamaan 24 kuukauden ajan. Kolmen hoitoviikon jälkeen pidettiin yhden viikon tauko. Hoito lopetettiin, jos ilmaantui vakavia haittavaikutuksia tai tauti eteni. Toisessa tutkimuksessa proteiinituotanto analysoitiin immunohistokemiallisesti munuaissyöpäpotilaiden kasvainnäytteistä, joita oli säilytetty parafiinissa. Kasvainnäytteet oli otettu talteen munuaisen poistoleikkauksen yhteydessä. Nämä potilaat jaettiin kolmeen eri ryhmään: metastasointi primaarivaiheessa (n=29), metastasointi myöhemmin (n=37) ja ei metastasointia (n=51). Keskimääräinen alfainterferonihoidon kesto oli 11 kuukautta (kk) [0,5 – 32 kk]. Objektiivinen hoitovaste todettiin 17 %:lla, tautitilanne pysyi ennallaan 42 %:lla ja myöhäinen vaste (yli 12 kk:tta hoidon aloittamisesta) todettiin 3 %:lla. Aika vasteen saavuttamisesta taudin etenemiseen oli keskimäärin 8 kk ja elinaika 19,1 kk. Viiden vuoden elossaololuku oli 16 %. Jos metastasoituneella munuaissyöpäpotilaalla oli keuhkometastasointi, hän selvisi todennäköisemmin viisi vuotta kuin muut potilaat. Henkeä uhkaavia sivuvaikutuksia ei todettu. Yli 12 kk:n ajan kestävä alfainterferonihoito on hyödyllistä niille potilaille, jotka ovat saaneet objektiivisen hoitovasteen tai tautitilanne on pysynyt ennallaan. Positiivinen p53- ja Ki-67-ekspressio yhdessä viittaavat suureen metastasoinnin todennäköisyyteen. Positiivinen COX-2-ekspressio viittaa viivästyneeseen metastaasien ilmaantumiseen. Metastasoituneilla potilailla positiiviset p53- ja Ki-67-ekspressiot viittaavat huonoon ennusteeseen, mutta positiivinen COX-2 ekspressio viittaa suotuisaan ennusteeseen. Positiivinen COX-2- ja negatiivinen Ki-67-ekspressio yhdessä viittaavat parantuneeseen ennusteeseen metastasoituneessa munuaissyövässä.

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Crohn´s disease (CD) is a chronic transmural inflammation of the gastrointestinal tract of unknown cause. Malnutrition associated with active CD has been reduced although obesity has increased. Dietary strategies such as those with high-protein have been proposed to reduce body fat. This study compares the effects of two supplements on the nutritional status of CD patients. 68 CD patients were randomized in two groups: whey protein group (WP) and soy protein group (SP). Using bioimpedance analysis, anthropometry and albumin and pre-albumin dosages the nutritional status was measured before starting the intervention and after 8 and 16 weeks. The disease activity was determined by Crohn's Disease Activity Index and serum C-reactive protein dosage and dietary intake by 24h dietary recalls. Forty-one patients concluded the study and both supplements changed body composition similarly. Triceps skin fold thickness (p< 0.001) and body fat percentage (p=0.001) decreased, whereas mid-arm muscle circumference (p=0.004), corrected arm muscle area (p=0.005) and body lean percentage (p=0.001) increased. For Crohn's disease patients undergoing anti TNF-alpha and azatioprine therapies, supplementation with whey and soy proteins changes body composition through reduction of body fat and thus contributes to control inflammation.

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Beh double dagger et`s disease (BD) is a multisystem chronic inflammatory disorder characterized by oral and genital ulceration and ocular involvement. Recurrent oral and genital ulcers are the most common symptoms of BD and occur in more than 80% of patients. The treatments of these disease manifestations include colchicine, corticosteroids and immunosuppressive drugs in severe cases. Anti-TNF-alpha therapy may be useful in refractory severe BD, particularly for ocular, central nervous system, gastrointestinal and refractory mucocutaneous lesions. During a 2-year period, 280 patients suffering from rheumatic diseases received anti-TNF-alpha agents at the infusion center of our University Hospital. Two patients (0.7%) presented BD; one of them had celiac disease as well, with recalcitrant mucocutaneous lesions that were not responsive to immunosuppressive drugs. We reported those patients who were successfully treated with infliximab and adalimumab, despite their late response.

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BACKGROUND: The purpose of this study is to describe the experience of Jules Gonin Eye Hospital on the long-term outcome of anti-TNF-alpha therapy in chronic non-infectious uveitis. PATIENTS AND METHODS: We identified and followed those patients with chronic non-infectious uveitis who received systemic anti-TNF-alpha therapy. Anti-TNF-alpha therapy was administered when no response had been obtained with classical immunosuppressive therapies or in the presence of severe rheumatoid disease. RESULTS: Fifteen patients (28 eyes), 7 male and 8 female (mean age, 43 years; range: 7 to 70 years) were identified. Diagnoses included HLA-B27-associated anterior uveitis (n = 4), sarcoidosis (n = 2), juvenile idiopathic arthritis (n = 2), idiopathic retinal vasculitis with uveitis (n = 2), pars planitis (n = 2), Adamantiades-Behçet disease (n = 1), birdshot retinochoroidopathy (n = 1), and Crohn's disease (n = 1). Mean duration of ocular disease was 8 years (range: 1 to 29 years). Treatment with infliximab (n = 11), etanercept (n = 2), or adalimumab (n = 2) was initiated. One patient with etanercept was switched to infliximab due to lack of clinical response. Clinical and angiographic regression of uveitis was observed within the first two months of therapy in all patients, and was maintained throughout the entire follow-up period (mean 18 months; range: 3 - 72 months). Recurrence was observed in 3 patients, and resolved after adjustment of therapy. Adverse events were recorded in only one patient (arterial hypotension). CONCLUSIONS: In this series of patients with chronic non-infectious uveitis, anti-TNF-alpha therapy was effective and safe. Further clinical studies are needed to determine an adequate duration of therapy.

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Interferon alpha (IFN-alpha) therapy is associated with a number of immunological side-effects, including autoimmune diseases and a 10% prevalence of thyroiditis. Hepatitis C virus (HCV) infection itself predisposes to autoimmune phenomena including hypothyroidism and myositis. The development of clinical hypothyroidism in the presence of positive thyroid antibodies in patients infected with HCV and treated with IFN-alpha suggests a possible association between the viral disease and the therapy. HCV infection may predispose to autoimmune thyroid disease and IFN-alpha therapy may secondarily lead to the development of thyroid dysfunctions. We report the single case of a female patient who developed a severe proximal myopathy in conjunction with primary hypothyroidism (Hoffmann's syndrome) secondarily to IFN-alpha therapy for HCV infection. This case highlights the need for careful clinical and biological monitoring for potential side-effects in such patients.

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The treatment of stage IV melanoma has witnessed a very impressive pace of innovation in recent years, to a point where the management of these patients has very little in common to what was standard practice 5 years ago. If the gain in overall survival, the high response rates or the induction of a significant fraction of long survivors are all very exciting news for our patients and their families, the path that led to these discoveries is as important. Rather than empirical, the development of these new strategies has been extremely rational, based on state-of-the-art basic biology and immunology, exemplary translational research and, finally, hypothesis-driven targeted trials that led to rapid approval. In this review, we will cover all the new targeted therapies that have emerged as the results of these translational programs, focusing mainly on signaling pathway- and immune checkpoint-targeted therapies. Taken collectively, these new developments set the bar for a new paradigm in future translational and clinical research in both melanoma as well as other tumor types.

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New oral targeted anticancer therapies are revolutionizing cancer treatment by transforming previously deadly malignancies into chronically manageable conditions. Nevertheless, drug resistance, persistence of cancer stem cells, and adverse drug effects still limit their ability to stabilize or cure malignant diseases in the long term. Response to targeted anticancer therapy is influenced by tumor genetics and by variability in drug concentrations. However, despite a significant inter-patient pharmacokinetic variability, targeted anticancer drugs are essentially licensed at fixed doses. Their therapeutic use could however be optimized by individualization of their dosage, based on blood concentration measurements via the therapeutic drug monitoring (TDM). TDM can increase the probability of therapeutic responses to targeted anticancer therapies, and would help minimize the risk of major adverse reactions.

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Interferon (IFN)-alpha receptor mRNA expression in liver of patients with chronic hepatitis C has been shown to be a response to IFN-alpha therapy. The objective of the present study was to determine whether the expression of mRNA for subunit 1 of the IFN-alpha receptor (IFNAR1) in peripheral blood mononuclear cells (PBMC) is associated with the response to IFN-alpha in patients with chronic hepatitis C. Thirty patients with positive anti-HCV and HCV-RNA, and abnormal levels of alanine aminotransferase in serum were selected and treated with IFN-alpha2b for one year. Those with HBV or HIV infection, or using alcohol were not included. Thirteen discontinued the treatment and were not evaluated. The IFN-alpha response was monitored on the basis of alanine aminotransferase level and positivity for HCV-RNA in serum. IFNAR1-mRNA expression in PBMC was measured by reverse transcription-polymerase chain reaction before and during the first three months of therapy. The results are reported as IFNAR1-mRNA/ß-actin-mRNA ratio (mean ± SD). Before treatment, responder patients had significantly higher IFNAR1-mRNA expression in PBMC (0.67 ± 0.15; N = 5; P < 0.05) compared to non-responders (0.35 ± 0.17; N = 12) and controls (0.30 ± 0.16; N = 9). Moreover, IFNAR1-mRNA levels were significantly reduced after 3 months of treatment in responders, whereas there were no differences in IFNAR1 expression in non-responders during IFN-alpha therapy. Basal IFNAR1-mRNA expression was not correlated with the serum level of alanine and aspartate aminotransferases or the presence of cirrhosis. The present results suggest that IFNAR1-mRNA expression in PBMC is associated with IFN-alpha response to hepatitis C and may be useful for monitoring therapy in patients with chronic hepatitis C.

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The low-energy β− emitter 161Tb is very similar to 177Lu with respect to half-life, beta energy and chemical properties. However, 161Tb also emits a significant amount of conversion and Auger electrons. Greater therapeutic effect can therefore be expected in comparison to 177Lu. It also emits low-energy photons that are useful for gamma camera imaging. The 160Gd(n,γ)161Gd→161Tb production route was used to produce 161Tb by neutron irradiation of massive 160Gd targets (up to 40 mg) in nuclear reactors. A semiautomated procedure based on cation exchange chromatography was developed and applied to isolate no carrier added (n.c.a.) 161Tb from the bulk of the 160Gd target and from its stable decay product 161Dy. 161Tb was used for radiolabeling DOTA-Tyr3-octreotate; the radiolabeling profile was compared to the commercially available n.c.a. 177Lu. A 161Tb Derenzo phantom was imaged using a small-animal single-photon emission computed tomography camera. Up to 15 GBq of 161Tb was produced by long-term irradiation of Gd targets. Using a cation exchange resin, we obtained 80%–90% of the available 161Tb with high specific activity, radionuclide and chemical purity and in quantities sufficient for therapeutic applications. The 161Tb obtained was of the quality required to prepare 161Tb–DOTA-Tyr3-octreotate. We were able to produce 161Tb in n.c.a. form by irradiating highly enriched 160Gd targets; it can be obtained in the quantity and quality required for the preparation of 161Tb-labeled therapeutic agents.

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The efficacy of traditional anti-cancer agents is hampered by toxicity to normal tissues, due to the lack of specificity for malignant cells. Recent advances in our understanding of molecular genetics and tumor biology have led to the identification of signaling pathways and their regulators implicated in tumorigenesis and malignant progression. Consequently, novel biological agents were designed which specifically target key regulators of cell survival and proliferation activated in malignant cells and thus are superior to unspecific cytotoxic agents. Antisense molecules comprising conventional single-stranded antisense oligonucleotides (ASO) and small interfering RNA (siRNA) inhibit gene expression on the transcript level. Thus, they specifically target the genetic basis of cancer and are particularly useful for inhibiting the expression of oncogenes the protein products of which are inaccessible to small molecules or inhibitory antibodies. Despite the somewhat disappointing results of recent antisense oncology trials, the identification of new cancer targets and ongoing progress in ASO and siRNA technology together with improvements in tumor targeted delivery have raised new hopes that this fascinating intervention concept will eventually translate into enhanced clinical efficacy.

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The aim of my Ph. D. thesis is to generalize a method for targeted anti-cancer drug delivery. Hydrophilic polymer-drug conjugates involve complicated synthesis; drug-encapsulated polymeric nanoparticles limit the loading capability of payloads. This thesis introduces the concept of nanoconjugates to overcome difficulties in synthesis and formulation. Drugs with hydroxyl group are able to initiate polyester synthesis in a regio- and chemo- selective way, with the mediation of ligand-tunable Zinc catalyst. Herein, three anti-cancer drugs are presented to demonstrate the high efficiency and selectivity in the method (Chapter 2-4). The obtained particles are stable in salt solution, releasing drugs over weeks in controlled manner. With the conjugation of aptamer, particles are capable to target prostate cancer cells in vitro. These results open the gateway to evaluate the in vivo efficacy of nanoconjugates for target cancer therapy (Chapter 5). Mechanism study of the polymerization leads to the discovery of chemosite selective synthesis of prodrugs with acrylate functional groups. Functional copolymer-drug conjugates will expand the scope of nanoconjugates (Chapter 6). Liposome-aptamer targeting drug delivery vehicle is well studied to achieve reversible cell-specific delivery of non-hydoxyl drugs e.g. cisplatin (Chapter 7). New monomers and polymerization mechanisms are explored for polyester in order to synthesize nanoconjugates with variety on properties (Chapter 8). Initial efforts to apply this type of prodrugs will be focused on the preparation of hydrogels for stem cell research (Chapter 9).