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101.
Dyson PG Horvath N Joshua D Barrow L Van Holst NG Brown R Gibson J To LB 《Bone marrow transplantation》2000,25(11):1175-1184
A potential problem of autologous transplantation in the treatment of multiple myeloma (MM) is the infusion of tumor cells. CD34+ selection has been used to purge autografts in MM and it is also possible to reduce tumour cell contamination of autografts by cytotoxic drug therapy prior to peripheral blood stem cell (PBSC) collection. To evaluate the effectiveness of a protocol combining multiple cycles of high-dose therapy and CD34+ selection to reduce tumour contamination of PBSC autografts, 34 MM patients were entered on a treatment schedule comprising two sequential cycles of mobilisation, CD34+ selection, and transplantation following high-dose therapy. In the second cycle of mobilisation there was a five-fold reduction in tumour contamination of the stem cell harvest (0.5 x 106/kg) compared with the first cycle (2.5 x 106/kg). In the 97 CD34+ selection procedures performed a median of 185 x 108 mononuclear cells (MNC) were processed yielding a median of 0.98 x 108 CD34+-enriched cells. CD34+ cells were enriched 68-fold from 1. 3% to 88.6%. The median yield of CD34+ cells was 42.2%. Following CD34+ selection the tumour cell contamination of the leukapheresis product was reduced by a median of 2.7 logs. This study demonstrates that in multiple myeloma a significant reduction in the malignant contamination of stem cell autografts can be achieved by combining the in vivo purging effect of cytotoxic therapy with in vitro purging by CD34+ selection. 相似文献
102.
Hunger-promoting AgRP neurons trigger an astrocyte-mediated feed-forward autoactivation loop in mice
Luis Varela Bernardo Stutz Jae Eun Song Jae Geun Kim Zhong-Wu Liu Xiao-Bing Gao Tamas L. Horvath 《The Journal of clinical investigation》2021,131(10)
Hypothalamic feeding circuits have been identified as having innate synaptic plasticity, mediating adaption to the changing metabolic milieu by controlling responses to feeding and obesity. However, less is known about the regulatory principles underlying the dynamic changes in agouti-related protein (AgRP) perikarya, a region crucial for gating of neural excitation and, hence, feeding. Here we show that AgRP neurons activated by food deprivation, ghrelin administration, or chemogenetics decreased their own inhibitory tone while triggering mitochondrial adaptations in neighboring astrocytes. We found that it was the inhibitory neurotransmitter GABA released by AgRP neurons that evoked this astrocytic response; this in turn resulted in increased glial ensheetment of AgRP perikarya by glial processes and increased excitability of AgRP neurons. We also identified astrocyte-derived prostaglandin E2, which directly activated — via EP2 receptors — AgRP neurons. Taken together, these observations unmasked a feed-forward, self-exciting loop in AgRP neuronal control mediated by astrocytes, a mechanism directly relevant for hunger, feeding, and overfeeding. 相似文献
103.
E. Horvath K. Kovacs H. S. Smyth M. Cusimano W. Singer 《Ultrastructural pathology》2013,37(6):511-524
The silent adenoma subtype 3 (SAS-3) of undetermined cellular derivation is a seemingly nonfunctioning aggressive pituitary tumor with a high recurrence rate. At the time of diagnosis SAS-3s are macro- or giant adenomas particularly aggressive in young individuals, especially women. They are usually associated with mild hyperprolactinemia and are unremarkable by histology. Immunohistochemistry, demonstrating scattered immunoreactivity mostly for GH, PRL, TSH, and α-subunit, is not diagnostic. Presently, only TEM permits conclusive diagnosis. Ultrastructurally, the large polar adenoma cells contain abundant RER, masses of SER, extensive multipolar Golgi apparatus, and unevenly clustered mitochondria, displaced by RER and SER, which may show close spatial relationship to RER. Cell membranes often form plexiform interdigitations. Nuclear pleomorphism and nuclear inclusions are common. The 100- to 200-nm secretory granules accumulate heavily in cell processes, which is a hallmark of glycoprotein hormone cell differentiation. The endothelial cells may contain tubuloreticular inclusions. Complete surgical removal of the large often invasive tumors is difficult necessitating postoperative treatment. SAS-3 is sensitive to conventional radiation. Some tumors express somatostatin receptors and respond well to somatostatin analogues, offering long-term control in patients with residual tumor. Possible derivation of SAS-3 from rostral thyrotrophs, a cell type presently known in rodents is comtemplated. 相似文献
104.
Marco Gerlinger Sergio A Quezada Karl S Peggs Andrew JS Furness Rosalie Fisher Teresa Marafioti Vishvesh H Shende Nicholas McGranahan Andrew J Rowan Steven Hazell David Hamm Harlan S Robins Lisa Pickering Martin Gore David L Nicol James Larkin Charles Swanton 《The Journal of pathology》2013,231(4):424-432
The recognition of cancer cells by T cells can impact upon prognosis and be exploited for immunotherapeutic approaches. This recognition depends on the specific interaction between antigens displayed on the surface of cancer cells and the T cell receptor (TCR), which is generated by somatic rearrangements of TCR α‐ and β‐chains (TCRb). Our aim was to assess whether ultra‐deep sequencing of the rearranged TCRb in DNA extracted from unfractionated clear cell renal cell carcinoma (ccRCC) samples can provide insights into the clonality and heterogeneity of intratumoural T cells in ccRCCs, a tumour type that can display extensive genetic intratumour heterogeneity (ITH). For this purpose, DNA was extracted from two to four tumour regions from each of four primary ccRCCs and was analysed by ultra‐deep TCR sequencing. In parallel, tumour infiltration by CD4, CD8 and Foxp3 regulatory T cells was evaluated by immunohistochemistry and correlated with TCR‐sequencing data. A polyclonal T cell repertoire with 367–16 289 (median 2394) unique TCRb sequences was identified per tumour region. The frequencies of the 100 most abundant T cell clones/tumour were poorly correlated between most regions (Pearson correlation coefficient, –0.218 to 0.465). 3–93% of these T cell clones were not detectable across all regions. Thus, the clonal composition of T cell populations can be heterogeneous across different regions of the same ccRCC. T cell ITH was higher in tumours pretreated with an mTOR inhibitor, which could suggest that therapy can influence adaptive tumour immunity. These data show that ultra‐deep TCR‐sequencing technology can be applied directly to DNA extracted from unfractionated tumour samples, allowing novel insights into the clonality of T cell populations in cancers. These were polyclonal and displayed ITH in ccRCC. TCRb sequencing may shed light on mechanisms of cancer immunity and the efficacy of immunotherapy approaches. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
105.
Background
Ovarian cancer has a different prognosis between early (I and II) and advanced stage (III and IV). The mechanism of disease progression is unknown, but patients with advanced disease may have a higher propensity for seeding of the abdominal cavity early in the disease process than those with early stage. Theoretically if this is so, then patients with advanced stage should have smaller sized tumors than patients with early stage.Methods
This was a retrospective chart review of patients in the tumor registry in 2003–2006. Patients had epithelial ovarian cancer, other cell types were excluded. Only cases with documentation of surgical and pathologic staging and measured dimensions on pathologic specimen were included. Patient stage and all available dimensions measured on diseased ovaries were recorded. The dimensions for each patient were averaged into a single dimension for that patient, and then these measurements were totaled and averaged.Results
There were 110 patients analyzed: 85 with advanced disease, 25 with early stage. The average measurement was 4.8 cm in advanced disease, and was 10.7 cm in early stage disease. This difference was statistically significant (p < 0.001).Conclusions
Overall, patients with early stage ovarian cancer have diseased ovaries that are more than twice as large as those found in advanced disease. This finding supports the fact that early versus advanced ovarian cancer are 2 separate disease processes. Early stage grows locally and does not disseminate, and advanced stage disseminates while the tumor is still relatively small. Theoretically there may be a factor that separates these 2 into different diseases, where advanced disease patients have a substance produced by their tumor that allows for early dissemination, and early stage lacks this substance and only grows locally. Basic science research comparing the tissue microarrays of early versus advanced stage disease may be able to identify this difference. If the difference is found, perhaps therapy can be targeted against this difference, and screening tests for advanced ovarian cancer can be improved. 相似文献106.
Alba Tristán-Noguero PhD Eva Borràs PhD Marta Molero-Luis PhD Tessa Wassenberg MD PhD Tessa Peters MSc Marcel M. Verbeek PhD Michel Willemsen MD PhD Thomas Opladen MD PhD Kathrin Jeltsch PhD Roser Pons MD PhD Beat Thony PhD Gabriella Horvath MD Zuhal Yapici MD Jennifer Friedman MD Keith Hyland PhD Guillermo E. Agosta MD Eduardo López-Laso MD Rafael Artuch MD PhD Eduard Sabidó PhD Àngels García-Cazorla MD PhD 《Movement disorders》2021,36(3):690-703
107.
Abstract The purpose of the present investigation was to examine the precursors and familial conditions which sustain school-aged children's separation anxiety. In a prospective, longitudinal study of 99 mother–child dyads, infancy measures of infant–mother attachment security, maternal separation anxiety, and maternal sensitivity were used to predict children's self-reported symptoms of separation anxiety at age 6. Insecurely attached children reported more separation anxiety than securely attached children. Insecure-ambivalent children reported marginally more separation anxiety than securely attached children, but not more than insecure-avoidant attached children. Regression analysis showed infant–mother attachment security and mother's sensitivity added uniquely to the prediction of children's separation anxiety, but mother's separation anxiety did not. Mediation tests show that the effect of mother's separation anxiety on children's separation anxiety may be mediated by maternal sensitivity. Research and clinical implications are discussed. 相似文献
108.
Antagonist of growth hormone-releasing hormone induces apoptosis in LNCaP human prostate cancer cells through a Ca2+-dependent pathway 总被引:1,自引:0,他引:1 下载免费PDF全文
Rekasi Z Czompoly T Schally AV Boldizsar F Varga JL Zarandi M Berki T Horvath RA Nemeth P 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(9):3435-3440
Antagonists of growth hormone-releasing hormone (GHRH) exert antiproliferative effects directly on cancer cells, which are mediated by the tumoral GHRH receptors. However, the signal transduction pathways involved in antiproliferative effect of GHRH antagonists have not yet been elucidated. We used flow cytometry to investigate whether GHRH antagonist JV-1-38 can induce changes in the cytosolic free Ca2+ concentration leading to apoptosis in LNCaP human prostate cancer cells. JV-1-38 evoked prompt Ca2+ signal in a dose-dependent way (1-10 microM) and induced early stage of apoptosis in LNCaP human prostate cancer cells at a concentration effective in suppression of cell proliferation (10 microM) peaking after 3 h. Unexpectedly, agonist GHRH(1-29)NH2, which elevates cytosolic free Ca2+ concentration in pituitary somatotrophs at nanomolar concentrations, failed to induce Ca2+ signal or apoptosis even at a 10-fold higher concentration (100 microM). However, agonist GHRH(1-29)NH2 inhibited JV-1-38-induced Ca2+ signals in a dose-dependent way without affecting the antagonist-induced apoptosis. Peptides unrelated to GHRH did not induce Ca2+ signals in LNCaP human prostate cancer cells. EDTA (10 mM) or nifedipine (10 microM) significantly reduced the Ca2+ signal and early stage of apoptosis induced by JV-1-38, supporting the view that the increase in intracellular Ca2+ in response to JV-1-38 occurs primarily through extracellular Ca2+ entry through voltage-operated Ca2+ channels. In conclusion, GHRH antagonists activate tumoral GHRH receptors and are able to induce apoptosis in LNCaP human prostate cancer cells through a Ca2+-dependent pathway. Treatment with GHRH antagonists may offer a new approach to the therapy of prostate and other hormone-sensitive cancers. 相似文献
109.
Extraprostatic extension (EPE) of prostatic carcinoma: is its proximity to the surgical margin or Gleason score important? 下载免费PDF全文
110.
Synergistic action of resveratrol, an ingredient of wine, with Ara-C and tiazofurin in HL-60 human promyelocytic leukemia cells 总被引:4,自引:0,他引:4
Horvath Z Saiko P Illmer C Madlener S Hoechtl T Bauer W Erker T Jaeger W Fritzer-Szekeres M Szekeres T 《Experimental hematology》2005,33(3):329-335
OBJECTIVE: Resveratrol, a naturally occurring stilbene derivative, is a potent free-radical scavenger causing a number of biochemical and antineoplastic effects. It was shown to induce differentiation and apoptosis in leukemia cells. Resveratrol was also identified as an inhibitor of ribonucleotide reductase (RR), a key enzyme of DNA synthesis. We report about the biochemical effects of resveratrol on the concentration of deoxyribonucleoside triphosphates (dNTPs), the products of RR, and on the incorporation of 14C-labeled cytidine into the DNA of HL-60 human promyelocytic leukemia cells. MATERIALS AND METHODS: Incorporation of 14C-labeled cytidine into the DNA of resveratrol-treated HL-60 cells was measured. Concentration of dNTPs was determined by a HPLC method. Cytotoxic effects of resveratrol, Ara-C, and tiazofurin were analyzed using growth inhibition and clonogenic assays. Induction of apoptosis was studied using a Hoechst/propidium iodide staining method. RESULTS: We found that resveratrol effectively inhibited incorporation of 14C-labeled cytidine into DNA. Furthermore, incubation of HL-60 cells with resveratrol significantly decreased intracellular dCTP, dTTP, dATP, and dGTP concentrations. Based on these results, we investigated the combination effects of resveratrol with Ara-C or tiazofurin, both antimetabolites, which are known to exhibit synergistic effects in combination with other inhibitors of RR. In growth inhibition, apoptosis, and clonogenic assays, resveratrol acted synergistically with both Ara-C and tiazofurin in HL-60 cells. CONCLUSIONS: We conclude that resveratrol could become a viable candidate as one compound in the combination chemotherapy of leukemia and therefore deserves further testing. 相似文献