972 resultados para Adoptive T Cell Therapy


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PURPOSE: This multicenter phase III study evaluated the efficacy and safety of lapatinib, an epidermal growth factor receptor/ErbB2 inhibitor, administered concomitantly with chemoradiotherapy and as maintenance monotherapy in patients with high-risk surgically treated squamous cell carcinoma of the head and neck (SCCHN). PATIENTS AND METHODS: Patients with resected stage II to IVA SCCHN, with a surgical margin ≤ 5 mm and/or extracapsular extension, were randomly assigned to chemoradiotherapy (66 Gy total radiation dose and cisplatin 100 mg/m(2) per day administered on days 1, 22, and 43) plus placebo or lapatinib (1,500 mg per day) before and during chemoradiotherapy, followed by 12 months of maintenance monotherapy. RESULTS: Six hundred eighty-eight patients were enrolled (lapatinib, n = 346; placebo, n = 342). With a median follow-up time of 35.3 months, the study ended early because of the apparent plateauing of disease-free survival (DFS) events. Median DFS assessed by an independent review committee was 53.6 months and not reached for lapatinib and placebo, respectively (hazard ratio, 1.10; 95% CI, 0.85 to 1.43). Investigator-assessed results confirmed the independent review committee assessment. No significant differences in DFS by human papillomavirus status or overall survival were observed between treatment arms. Similar numbers of patients in both treatment arms experienced adverse events (AEs), with more patients in the lapatinib arm than the placebo arm experiencing serious AEs (48% v 40%, respectively). The most commonly observed treatment-related AEs were diarrhea and rash, both predominantly in the lapatinib arm. CONCLUSION: Addition of lapatinib to chemoradiotherapy and its use as long-term maintenance therapy does not offer any efficacy benefits and had additional toxicity compared with placebo in patients with surgically treated high-risk SCCHN.

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AbstractObjective:In the present study, the authors investigated the in vitrobehavior of radio-resistant breast adenocarcinoma (MDA-MB-231) cells line and radiosensitive peripheral blood mononuclear cells (PBMC), as a function of different radiation doses, dose rates and postirradiation time kinetics, with a view to the interest of clinical radiotherapy.Materials and Methods:The cells were irradiated with Co-60, at 2 and 10 Gy and two different exposure rates, 339.56 cGy.min–1 and the other corresponding to one fourth of the standard dose rates, present over a 10-year period of cobalt therapy. Post-irradiation sampling was performed at pre-established kinetics of 24, 48 and 72 hours. The optical density response in viability assay was evaluated and a morphological analysis was performed.Results:Radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates. MDAMB- 231 cells presented viability decrease only at higher dose and dose rate. The results showed MDA-MB-231 clone expansion at low dose rate after 48–72 hours post-radiation.Conclusion:Low dose rate shows a possible potential clinical impact involving decrease in management of radio-resistant and radiosensitive tumor cell lines in cobalt therapy for breast cancer.

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AbstractRenal cell carcinoma (RCC) is the seventh most common histological type of cancer in the Western world and has shown a sustained increase in its prevalence. The histological classification of RCCs is of utmost importance, considering the significant prognostic and therapeutic implications of its histological subtypes. Imaging methods play an outstanding role in the diagnosis, staging and follow-up of RCC. Clear cell, papillary and chromophobe are the most common histological subtypes of RCC, and their preoperative radiological characterization, either followed or not by confirmatory percutaneous biopsy, may be particularly useful in cases of poor surgical condition, metastatic disease, central mass in a solitary kidney, and in patients eligible for molecular targeted therapy. New strategies recently developed for treating renal cancer, such as cryo and radiofrequency ablation, molecularly targeted therapy and active surveillance also require appropriate preoperative characterization of renal masses. Less common histological types, although sharing nonspecific imaging features, may be suspected on the basis of clinical and epidemiological data. The present study is aimed at reviewing the main clinical and imaging findings of histological RCC subtypes.

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AIMS: Clinical trials suggest that intracoronary delivery of autologous bone marrow-derived cells (BMCs) 1-7 days post-acute myocardial infarction (AMI) may improve left ventricular (LV) function. Earlier time points have not been evaluated. We sought to determine the effect of intracoronary autologous BMC on LV function when delivered within 24 h of successful reperfusion therapy. METHODS AND RESULTS: A multi-centre phase II randomized, double-blind, and placebo-controlled trial. One hundred patients with anterior AMI and significant regional wall motion abnormality were randomized to receive either intracoronary infusion of BMC or placebo (1:1) within 24 h of successful primary percutaneous intervention (PPCI). The primary endpoint was the change in left ventricular ejection fraction (LVEF) between baseline and 1 year as determined by advanced cardiac imaging. At 1 year, although LVEF increased compared with baseline in both groups, the between-group difference favouring BMC was small (2.2%; 95% confidence interval, CI: -0.5 to 5.0; P = 0.10). However, there was a significantly greater myocardial salvage index in the BMC-treated group compared with placebo (0.1%; 95% CI: 0.0-0.20; P = 0.048). Major adverse events were rare in both treatment groups. CONCLUSION: The early infusion of intracoronary BMC following PPCI for patients with AMI and regional wall motion abnormality leads to a small non-significant improvement in LVEF when compared with placebo; however, it may play an important role in infarct remodelling and myocardial salvage. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT00765453 and EudraCT 2007-002144-16.

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Infertility is a common late effect of childhood cancer treatment. Testicular toxicity can clinically be first detected after the onset of pubertal maturation of the patients when the testis does not grow, spermatogenesis does not initiate and serum levels of gonadotrophins rise. Improved prognosis for childhood cancer has resulted in a growing number of childhood cancer survivors with late effects. In our study, we developed novel tools for detecting cancer therapy-related testicular toxicity during development. By using these methods the effects of the tyrosine kinase inhibitor imatinib mesylate, chemotherapy agent doxorubicin and irradiation on testicular development were investigated in rat and monkey. Patients with chronic myeloid leukemia and some patients with acute lymphoblastic leukemia have fusion gene BCR-ABL which codes for abnormal tyrosine kinase protein. Imatinib mesylate (Glivec®) inhibits activity of this protein. In addition, imatinib inhibits the action of the c-kit and PDGF –receptors, which are both important for the survival and proliferation of the spermatogonial stem cell pool. Imatinib exposure during prepubertal development disturbed the development and the growth of the testis. Spermatogonial stem cells were also sensitive to the toxic effects of doxorubicin and irradiation during the initiation phase of spermatogenesis. In addition, the effect of the treatment of acute lymphoblastic leukemia on germ cell numbers and recovery of reproductive functions after sexual maturation was investigated. Therapy for childhood acute lymphoblastic leukemia seldom results in infertility. The present study gives new information on the mechanisms by which cancer treatments exert their gonadal toxicity in immature testis.

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Caveolae are membrane micro-domains enriched in cholesterol, sphingolipids and caveolins, which are transmembrane proteins with a hairpin-like structure. Caveolae participate in receptor-mediated trafficking of cell surface receptors and receptor-mediated signaling. Furthermore, caveolae participate in clathrin-independent endocytosis of membrane receptors. On the one hand, caveolins are involved in vascular and cardiac dysfunction. Also, neurological abnormalities in caveolin-1 knockout mice and a link between caveolin-1 gene haplotypes and neurodegenerative diseases have been reported. The aim of this article is to present the rationale for considering caveolae as potential targets in cardiovascular and neurological diseases.

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The incidence of malignant melanoma of the skin has been steadily rising worldwide during the past decades. Most early detected primary tumors can be removed surgically and the prognosis is good. However, at the same time there still is no permanent cure for metastatic melanoma and its prognosis is poor, although lately new effective drugs have emerged. In this thesis, four different approaches of experimental therapy for metastatic melanoma were studied. Endogenous cis-Urocanic acid (UCA) is found in every individual’s skin, where exposure to UV light from the sun generates it from its inactive trans conformation. Cis- UCA was found to destroy malignant melanoma cells in culture under an acidified pH and sufficient concentration through caspase-3 mediated apoptosis. Furthermore, cis-UCA is able to considerably diminish the growth rate in human melanoma tumors on living SCID mice. Using replication-competent Semliki Forest viruses, human melanoma tumors grown in SCID mice were dramatically shrunken as the fulminant production of viruses in melanoma cells leads them to apoptosis within 72 hours. Small oligopeptides attaching to melanoma cells were identified using in vivo phage display. The melanoma-specific peptides found were further tested in vitro on adenoviruses. Ultimately, the adenoviral retargeting using the peptides was tested in vivo. One peptide homed to human transferring receptor upregulated on melanoma cells. In order to kill the malignant melanoma cells with the retargeted adenoviruses, the viruses should carry genetic material producing apoptotic proteins in the cancer tissue. TIMP-3 has been identified as a good candidate for such a protein, as it inhibits malignant cell adhesion as well as promotes apoptosis through a caspase-8 pathway. It is further shown here that adenovirally delivered TIMP-3 is even more potent, as it could kill non-adherent cancer cells, lacking the fully functional death receptor signalling pathway. Adenovirally delivered TIMP-2 also showed marked antitumor effects in human malignant melanoma xenografts on SCID mice both in ex vivo and systemic delivery.

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Background. Multiple myeloma (MM) is the second most common hematologic malignancy after lymphomas In Finland: the annual incidence of MM is approximately 200. For three decades the median survival remained at 3 to 4 years from diagnosis until high-dose melphalan treatment supported by autologous stem cell transplantation (ASCT) became the standard of care for newly diagnosed MM since the mid 1990’s and the median survival increased to 5 – 6 years. This study focuses on three important aspects of ASCT, namely 1) stem cell mobilization, 2) single vs. double ASCT as initial treatment, and 3) the role of minimal residual disease (MRD) for longterm outcome. Aim. The aim of this series of studies was to evaluate the outcomes of MM patients and the ASCT procedure at the Turku University Central Hospital, Finland. First, we tried to identify which factors predict unsuccessful mobilization of autologous stem cells. Second, we compared the use of short-acting granulocyte-colony stimulating factor (GCSF) with long-acting G-CSF as mobilization agents. Third, one and two successive ASCTs were compared in 100 patients with MM. Fourth, for patients in complete response (CR) after stem cell transplantation (SCT), patient-specific probes for quantitative allele-specific oligonucleotide polymerase-chain reaction (qASO-PCR) measurements were designed to evaluate MRD and its importance for long-term outcome. Results. The quantity of previous chemotherapy and previous interferon use were significant pre-mobilization factors that predicted mobilization failure, together with some factors related to mobilization therapy itself, such as duration and degree of cytopenias and occurrence of sepsis. Short-acting and long-acting G-CSF combined with chemotherapy were comparable as stem cells mobilizers. The progression free (PFS) and overall survival (OS) tended to be longer after double ASCT than after single ASCT with a median follow-up time of 4 years, but this difference disappeared as the follow-up time increased. qASO-PCR was a good and sensitive divider of the CR patients into two prognostic groups: MRD low/negative (≤ 0.01%) and MRD high (>0.01%) groups with a significant difference in PFS and suggestively also in OS. Conclusions. When the factors prediciting a poor outcome of stem cell mobilization prevail, it is possible to identify those patients who need specific efforts to maximize the mobilization efficacy. Long-acting pegfilgrastim is a practical and effective alternative to short-acting filgrastim for mobilization therapy. There is no need to perform double ASCT on all eligible patients. MRD assessment with qASO-PCR is a sensitive method for evaluation of the depth of the CR response and can be used to predict long-term outcome after ACST.

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The currently used forms of cancer therapy are associated with drug resistance and toxicity to healthy tissues. Thus, more efficient methods are needed for cancer-specific induction of growth arrest and programmed cell death, also known as apoptosis. Therapeutic forms of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) are investigated in clinical trials due to the capability of TRAIL to trigger apoptosis specifically in cancer cells by activation of cell surface death receptors. Many tumors, however, have acquired resistance to TRAIL-induced apoptosis and sensitizing drugs for combinatorial treatments are, therefore, in high demand. This study demonstrates that lignans, natural polyphenols enriched in seeds and cereal, have a remarkable sensitizing effect on TRAIL-induced cell death at non-toxic lignan concentrations. In TRAIL-resistant and androgen-dependent prostate cancer cells we observe that lignans repress receptor tyrosine kinase (RTK) activity and downregulate cell survival signaling via the Akt pathway, which leads to increased TRAIL sensitivity. A structure-activity relationship analysis reveals that the γ-butyrolactone ring of the dibenzylbutyrolactone lignans is essential for the rapidly reversible TRAIL-sensitizing activity of these compounds. Furthermore, the lignan nortrachelogenin (NTG) is identified as the most efficient of the 27 tested lignans and norlignans in sensitization of androgen-deprived prostate cancer cells to TRAIL-induced apoptosis. While this combinatorial anticancer approach may leave normal cells unharmed, several efficient cancer drugs are too toxic, insoluble or unstable to be used in systemic therapy. To enable use of such drugs and to protect normal cells from cytotoxic effects, cancer-targeted drug delivery vehicles of nanometer scale have recently been generated. The newly developed nanoparticle system that we tested in vitro for cancer cell targeting combines the efficient drug-loading capacity of mesoporous silica to the versatile particle surface functionalization of hyperbranched poly(ethylene imine), PEI. The mesoporous hybrid silica nanoparticles (MSNs) were functionalized with folic acid to promote targeted internalization by folate receptor overexpressing cancer cells. The presented results demonstrate that the developed carrier system can be employed in vitro for cancer selective delivery of adsorbed or covalently conjugated molecules and furthermore, for selective induction of apoptotic cell death in folate receptor expressing cancer cells. The tested carrier system displays potential for simultaneous delivery of several anticancer agents specifically to cancer cells also in vivo.

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Spermatogenesis, i.e sperm production in the seminiferous tubules of the testis, is a complex process that takes over one month to complete. Life-long ability of sperm production ultimately lies in a small population of undifferentiated cells, called spermatogonial stem cells (SSCs). These cells give rise to differentiating spermatogonia, which are committed to mature into spermatozoa. SSCs represent a heterogeneous population of cells and many aspects of their basic biology are still unknown. Understanding the mechanisms behind the cell fate decision of these cells is important to gain more insights into the causes of infertility and testis cancer. In addition, an interesting new aspect is the use of testis-derived stem cells in regenerative medicine. Our data demonstrated that adult mouse testis houses a population of Nanog-expressing spermatogonia. Based on mRNA and protein analysis these cells are enriched in stage XII of the mouse seminiferous epithelial cycle. The cells derived from this stage have the highest capacity to give rise to ES cell-like cells which express Oct4 and Nanog. These cells are under tight non- GDNF regulation but their fate can be dictated by activating p21 signalling. Comparative studies suggested that these cells are regulated like ES cells. Taken together these data imply that pluripotent cells are present in the adult mammalian testis. CIP2A (cancerous inhibitor of PP2A) has been associated with tumour aggressiveness and poor prognosis. In the testis it is expressed by the descendants of stem cells, i.e. the spermatogonial progenitor cells. Our data suggest that CIP2A acts upstream of PLZF and is needed for quantitatively normal spermatogenesis. Classification of CIP2A as a cancer/testis gene makes it an attractive target for cancer therapy. Study on the CIP2A deficient mouse model demonstrates that systemic inhibition of CIP2A does not severely interfere with growth and development or tissue or organ function, except for the spermatogenic output. These data demonstrate that CIP2A is required for quantitatively normal spermatogenesis. Hedgehog (Hh) signalling is involved in the development and maintenance of many different tissues and organs. According to our data, Hh signalling is active at many different levels during rat spermatogenesis: in spermatogonia, spermatocytes and late elongating spermatids. Localization of Suppressor of Fused (SuFu), the negative regulator of the pathway, specifically in early elongating spermatids suggests that Hh signalling needs to be shut down in these cells. Introduction of Hh signalling inhibitor resulted in an increase in germ cell apoptosis. Follicle-stimulating hormone (FSH) and inhibition of receptor tyrosine kinases resulted in down-regulation of Hh signalling. These data show that Hh signalling is under endocrine and paracrine control and it promotes germ cell survival.

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PURPOSES: To determine the basic expression of ABC transporters in an epithelial ovarian cancer cell line, and to investigate whether low concentrations of acetaminophen and ibuprofen inhibited the growth of this cell line in vitro. METHODS: TOV-21 G cells were exposed to different concentrations of acetaminophen (1.5 to 15 μg/mL) and ibuprofen (2.0 to 20 μg/mL) for 24 to 48 hours. The cellular growth was assessed using a cell viability assay. Cellular morphology was determined by fluorescence microscopy. The gene expression profile of ABC transporters was determined by assessing a panel including 42 genes of the ABC transporter superfamily. RESULTS: We observed a significant decrease in TOV-21 G cell growth after exposure to 15 μg/mL of acetaminophen for 24 (p=0.02) and 48 hours (p=0.01), or to 20 μg/mL of ibuprofen for 48 hours (p=0.04). Assessing the morphology of TOV-21 G cells did not reveal evidence of extensive apoptosis. TOV-21 G cells had a reduced expression of the genes ABCA1, ABCC3, ABCC4, ABCD3, ABCD4 and ABCE1 within the ABC transporter superfamily. CONCLUSIONS: This study provides in vitro evidence of inhibitory effects of growth in therapeutic concentrations of acetaminophen and ibuprofen on TOV-21 G cells. Additionally, TOV-21 G cells presented a reduced expression of the ABCA1, ABCC3, ABCC4, ABCD3, ABCD4 and ABCE1 transporters.

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The integrin family of transmembrane receptors are important for cell-matrix adhesion and signal transmission to the interior of the cell. Integrins are essential for many physiological processes and defective integrin function can consequently result in a multitude of diseases, including cancer. Integrin traffic is needed for completion of cytokinesis and cell division failure has been proposed to be an early event in the formation of chromosomally aberrant and transformed cells. Impaired integrin traffic and changes in integrin expression are known to promote invasion of malignant cells. However, the direct roles of impaired integrin traffic in tumorigenesis and increased integrin expression in oncogene driven invasion have not been examined. In this study we have investigated both of these aspects. We found that cells with reduced integrin endocytosis become binucleate and subsequently aneuploid. These aneuploid cells display characteristics of transformed cells; they are anchorage-independent, resistant to apoptosis and invasive in vitro. Importantly, subcutaneous injection of the aneuploid cells into athymic nude mice produced highly malignant tumors. Through gene expression profiling and analysis of integrin-triggered signaling pathways we have identified several molecules involved in the malignancy of these cells, including Src kinase and the transcription factor Twist2. Thus, even though chromosomal aberrations are associated with reduced cell fitness, we show that aneuploidy can facilitate tumor evolution and selection of transformed cells. Invasion and metastasis are the primary reason for deaths caused by cancer and the molecular pathways responsible for invasion are therefore attractive targets in cancer therapy. In addition to integrins, another major family of adhesion receptors are the proteoglycans syndecans. Integrins and syndecans are known to signal in a synergistic manner in controlling cell adhesion on 2D matrixes. Here we explored the role of syndecans as α2β1 integrin co-receptors in 3D collagen. We show that in breast cancer cells harbouring mutant K-Ras, increased levels of integrins, their co-receptors syndecans and matrix cleaving proteases are necessary for the invasive phenotype of these cells. Together, these findings increase our knowledge of the complicated changes that occur during tumorigenesis and the pathways that control the ability of cancer cells to invade and metastasize.

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The aim of this thesis was to develop new herpes simplex virus (HSV) vectors for gene therapy of experimental autoimmune encephalomyelitis (EAE), the principal model of multiple sclerosis (MS), and to study the pathogenesis of wild-type HSV-1 and HSV-1 vectors in vivo. By introducing potential immunomodulatory factors into mice with EAE we strived to develop therapies and possibly find molecules improving recovery from EAE. We aimed at altering the immune response by inducing favorable Th2-type cytokines, thus shifting the immune response from a Th1- or a Th17-response. Our HSV vector expressing interleukin (IL)-5 modulated the cytokine responses, decreased inflammation and alleviated EAE. The use of a novel method, bacterial artificial chromosome (BAC), for engineering recombinant HSV facilitated the construction of a new vector expressing leukemia inhibitory factor (LIF). LIF is a neurotropic cytokine with broad functions in the central nervous system (CNS). LIF promotes oligodendrocyte maturation and decreases demyelination and oligodendrocyte loss. The BAC-derived HSV-LIF vector alleviated the clinical symptoms, induced a higher number of oligodendrocytes and modulated T cell responses. By administering HSV via different infection routes, e.g. peripherally via the nose or eye, or intracranially to the brain, the effect of the immune response on HSV spread at different points of the natural infection route was studied. The intranasal infection was an effective delivery route of HSV to the trigeminal ganglion and CNS, whereas corneal infection displayed limited spread. The corneal and intranasal infections induced different peripheral immune responses, which might explain the observed differences in viral spread.

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Abstract: This study aimed to determine whether prepartum antimicrobial and/or Escherichia coli J5 vaccination in dairy heifers influence the milk production, milk quality, and estimate their economic benefit. Thus, 33 dairy heifers were enrolled in four groups using a split-splot design. Groups were: (G1) prepartum antimicrobial infusion and vaccination with an E. coli J5 bacterin, (G2) prepartum antimicrobial infusion, (G3) vaccination with an E. coli J5 bacterin, and (G4) control heifers. Composite milk samples for somatic cell count, total bacteria count and milk composition were collected 15 days after calving and every 15 days until the end of the experiment. Bacteriological analysis was carried out at the end of study. The milk production and the incidence of clinical cases of mastitis, as well as the costs associated with them were recorded. The results demonstrate a reduction on clinical mastitis rates by preventive strategies, which implicated in lower volume of discarded milk (0.99, 1.01, 1.04 and 3.98% for G1, G2, G3 and G4, respectively) and higher economic benefit. Thus, in well-managed dairy herds the prevention of heifer mastitis by vaccination or antimicrobial therapy can reduce the amount of antimicrobials needed to treat clinical mastitis cases and the days of discarded milk.

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Gene therapy is the treatment of diseases based on the transfer of genetic information. Agents that carry or deliver DNA to target cells are called vectors (Latin vector: carrier, deliverer). Ideally, a vector should accommodate an unlimited amount of inserted DNA, lack the ability of autonomous replication of its own DNA, be easily manufactured, and be available in concentrated form. Secondly, it should have the ability to target specific cell types or to limit its gene expression to specific cell types, and to achieve sustained gene expression in the long term or in a controlled fashion. Finally, it should not be toxic or immunogenic. Such a vector does not exist and none of the DNA delivery systems so far available for in vivo gene transfer is perfect with respect to any of these points. Gene therapy and the means to promote it depend heavily on the development and improvement of new gene vector systems.