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71.
Functional and prognostic significance of the genomic amplification of frizzled 6 (FZD6) in breast cancer 下载免费PDF全文
Gabriele Corda Gianluca Sala Rossano Lattanzio Manuela Iezzi Michele Sallese Giorgia Fragassi Alessia Lamolinara Hasan Mirza Daniela Barcaroli Sibylle Ermler Elisabete Silva Hemad Yasaei Robert F Newbold Paola Vagnarelli Marcella Mottolese Pier Giorgio Natali Letizia Perracchio Jelmar Quist Anita Grigoriadis Pierfrancesco Marra Andrew N Tutt Mauro Piantelli Stefano Iacobelli Vincenzo De Laurenzi Arturo Sala 《The Journal of pathology》2017,241(3):350-361
Frizzled receptors mediate Wnt ligand signalling, which is crucially involved in regulating tissue development and differentiation, and is often deregulated in cancer. In this study, we found that the gene encoding the Wnt receptor frizzled 6 (FZD6) is frequently amplified in breast cancer, with an increased incidence in the triple‐negative breast cancer (TNBC) subtype. Ablation of FZD6 expression in mammary cancer cell lines: (1) inhibited motility and invasion; (2) induced a more symmetrical shape of organoid three‐dimensional cultures; and (3) inhibited bone and liver metastasis in vivo. Mechanistically, FZD6 signalling is required for the assembly of the fibronectin matrix, interfering with the organization of the actin cytoskeleton. Ectopic delivery of fibronectin in FZD6‐depleted, triple‐negative MDA‐MB‐231 cells rearranged the actin cytoskeleton and restored epidermal growth factor‐mediated invasion. In patients with localized, lymph node‐negative (early) breast cancer, positivity of tumour cells for FZD6 protein identified patients with reduced distant relapse‐free survival. Multivariate analysis indicated an independent prognostic significance of FZD6 expression in TNBC tumours, predicting distant, but not local, relapse. We conclude that the FZD6–fibronectin actin axis identified in our study could be exploited for drug development in highly metastatic forms of breast cancer, such as TNBC. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
72.
AIMS: Centrally located prostatic ductal adenocarcinoma can present as a single urethral polyp mimicking a benign polyp. Such lesions have not been formally studied. METHODS AND RESULTS: Clinicopathological and immunohistochemical findings of eight cases were analysed. Patients (mean age 76 years) presented with urinary symptoms and haematuria. Mean serum prostate specific antigen (PSA) was 7.01 ng/mL (range 1.04-21). Single small polyps were seen on cystourethroscopy with a clinical diagnosis of benign polyps. The most common architectural patterns were cribriform and papillary. Five cases had mild cytological atypia, three of which were initially diagnosed as benign prostatic urethral polyps. All cases were positive for PSA and 34betaE12. Seven cases tested were positive for AMACR (a-methylacyl-CoA racemase), p63 and cytokeratin (CK) 7 and 70% for CK20. Proliferative activity defined as Ki-67 labelling index was high (mean 26%, range 20-35%). Adenocarcinoma, predominantly ductal, was found in other specimens in four patients. CONCLUSIONS: Centrally located prostatic ductal adenocarcinoma has the propensity to mimic benign urethral polyps clinically and histopathologically. Basal cell immunostaining may not help with this distinction but AMACR is useful. Prominent glandular complexity including cribriform patterns, nuclear pseudostratification, at least mild atypia and a high Ki-67 index distinguish these lesions from prostatic urethral polyps. 相似文献
73.
Elisa Giannoni Maria Letizia Taddei Matteo Parri Francesca Bianchini Michela Santosuosso Renata Grifantini Gabriella Fibbi Benedetta Mazzanti Lido Calorini Paola Chiarugi 《Journal of molecular medicine (Berlin, Germany)》2013,91(1):103-115
Tumor progression is deeply influenced by epigenetic changes induced by tumor stroma. Cancer-associated fibroblasts (CAFs) have been reported to promote epithelial–mesenchymal transition in cancer cells, thereby enhancing their aggressiveness and stem-like properties. As CAFs are able to recruit endothelial progenitor cells (EPCs) to tumor site, we aim to investigate their interplay for prostate carcinoma progression. Both prostate CAFs and cancer cells actively recruit EPCs, known to affect tumor progression through increased vasculogenesis. EPCs synergize with CAFs to further promote epigenetic plasticity of cancer cells, through a mesenchymal-to-amoeboid transition. Indeed, after fibroblasts have engaged epithelial–mesenchymal transition in cancer cells, a further shift towards amoeboid motility is promoted by EPCs through contact-mediated triggering of the bidirectional ephrinA1/EphA2 signaling. The activation of ephrinA1 reverse pathway enhances EPC-induced neo-vascularization, thus promoting tumor growth, while EphA2 forward signaling elicits mesenchymal–amoeboid transition in cancer cells, favoring their adhesion to endothelium, transendothelial migration, and lung metastatic colonization. We therefore underscore that the metastatic advantage given by tumor microenvironment embraces different motility strategies and propose EphA2-targeted tools as useful adjuvants in anti-metastatic treatments. 相似文献
74.
75.
F. Armougom F. Bittar N. Stremler J.-M. Rolain C. Robert J.-C. Dubus J. Sarles D. Raoult B. La Scola 《European journal of clinical microbiology & infectious diseases》2009,28(9):1151-1154
Recent studies using 16S rRNA gene amplification followed by clonal Sanger sequencing in cystic fibrosis demonstrated that
cultured microorganisms are only part of the infecting flora. The purpose of this paper was to compare pyrosequencing and
clonal Sanger sequencing on sputum. The sputum of a patient with cystic fibrosis was analysed by culture, Sanger clone sequencing
and pyrosequencing after 16S rRNA gene amplification. A total of 4,499 sequencing reads were obtained, which could be attributed
to six consensus sequences, but the length of reads leads to fastidious data analysis. Compared to clonal Sanger sequencing
and to cultivation results, pyrosequencing recovers greater species richness and gives a more reliable estimate of the relative
abundance of bacterial species. The 16S pyrosequencing approach expands our knowledge of the microbial diversity of cystic
fibrosis sputum. The current lack of phylogenetic resolution at the species level for the GS 20 sequencing reads will be overcome
with the next generation of pyrosequencing apparatus. 相似文献
76.
Maria Caterina Grassi Anna Maria Cioce Franco Dei Giudici Letizia Antonilli Paolo Nencini 《Pharmacological research》2007,55(2):117-121
Cocaine abusers frequently report taking the drug in association with alcohol. This combined intake leads to the synthesis of cocaethylene, an active metabolite with effects similar to those of cocaine, but more prolonged. Since pharmacological effects of cocaethylene may partially account for the habit of cocaine abusers to take the drug in combination with ethanol, a main therapeutic goal in these patients should be making body fluids negative for cocaethylene. This randomized controlled open study conducted on 12 subjects co-abusers of cocaine and alcohol, evaluates the efficacy of a 12-week pharmacological treatment with Disulfiram (DIS) 400mg daily or Naltrexone (NTX) 50mg daily associated with Cognitive Behaviour Therapy (CBT), as compared to CBT alone, in terms of: (i) stay in treatment; (ii) drug-free urinalyses for cocaine and cocaethylene; (iii) reduction of alcohol and cocaine craving. Data presented in this study are restricted to the first 4 weeks of treatment when all the enrolled subjects were still available for examination. In fact, of the 12 subjects enrolled in the study only 4 (33%) completed the 12-week treatment. Of these, three were in the CBT group and one in the NTX/CBT group. Results show that CBT treated subjects remained in treatment longer than those assigned to either DIS/CBT or NTX/CBT therapies. However, during the first 4 weeks of treatment, CBT-group urine tested positive almost always for both cocaine and cocaethylene. In contrast, both DIS/CBT and NTX/CBT treatments were associated to a statistically significant reduction, of positive urinalysis for both cocaine and cocaethylene, with respect to CBT alone. Moreover, across the first 4 weeks of treatment DIS/CBT and NTX/CBT treated subjects maintained lower scores at Visual Analogue Scales (VAS) for both cocaine and alcohol craving than subjects receiving CBT alone. This pilot study suggests that the transient efficacy of pharmacological treatments in maintaining subjects drug free, does not add to the capability of CBT to retain them in treatment. 相似文献
77.
A Ghidini M Sirtori P Vergani S Mariani E Tucci G C Scola 《American journal of obstetrics and gynecology》1989,160(1):86-87
In utero sonographic visualization of fetal intracranial calcifications during the second trimester is reported. Its diagnostic process, which included percutaneous umbilical cord blood sampling and fetal paracentesis, is described. 相似文献
78.
Campos EC Schiavi C Bolognesi A Bellusci C Lubelli C Duca A Polito L Poulas K Tzartos SJ Stirpe F 《Current eye research》2002,24(1):58-65
PURPOSE: To evaluate the effects on extraocular muscles of a skeletal muscle-specific immunotoxin, saporin-mAb 73, as an alternative to botulinum toxin to induce a permanent correction of oculo-facial dystonias or some forms of ocular motility disorders. METHODS: An immunotoxin was prepared with a monoclonal antibody (mAb 73) against acetylcholine receptors of skeletal muscle, linked to saporin, a type 1 ribosome-inactivating protein (RIP) from Saponaria officinalis. Sixteen New Zealand white rabbits were treated with a single injection of immunotoxin directly into the medial rectus muscle of one eye. Four different dosages of 2, 5, 20, or 50 ng saporin-mAb 73 were used. The rabbits were sacrificed at two, 7 and 14 days post-injection. The medial rectus muscle and the retractor bulbi muscle of both the injected and the fellow eyes were taken and serial sections were examined by light microscopy in a blinded manner. RESULTS: Saporin-mAb 73, even at the dosage of 2 ng, brought about focal damage in the extraocular muscles of rabbits without histological changes in adjacent muscles. The histological examination revealed necrotic/apoptotic lesions restricted to the sites of inoculation and largely infiltrated by macrophages. No evident inflammatory reaction was detected at any time and neutrophils were substantially absent. At 14 days after injection, necrosis/apoptosis was still evident and the sclerotic reaction was minimal. CONCLUSIONS: The immunotoxin saporin-mAb 73 injections into the extraocular muscles of rabbits caused focal damage to the muscles. There was no significant inflammatory reaction and muscle fiber loss was present even at the lower doses. Although the lesions were followed for only 14 days, our results suggest that saporin-mAb 73 has potential to cause safe focal muscle damage but longer-term follow-up are needed to investigate the persistence of muscle weakness. 相似文献
79.
Boriani G Biffi M Bacchi L Martignani C Zannoli R Butrous GS Branzi A 《European journal of clinical pharmacology》2002,58(3):165-169
OBJECTIVE: To assess the haemodynamic effects of short-term treatment with dofetilide in comparison with sotalol in patients with ischaemic heart disease. METHODS: Twelve patients with ischaemic heart disease and sustained ventricular tachycardia were treated with dofetilide [500 microg twice daily (b.i.d.)] or sotalol (160 mg b.i.d., randomised sequence separated by wash-out period) for 3-5 days. Right-heart catheterisation was performed at baseline and at the end of each short-term treatment phase. RESULTS: The main findings were a significant reduction in heart rate, mean systemic pressure and cardiac index (-13%) during treatment with sotalol. Conversely, cardiac index increased significantly during dofetilide (mean percentage change 11%) with no effect on heart rate and systemic blood pressure. CONCLUSIONS: Oral dofetilide exerts favourable haemodynamic effects in comparison with D,L-sotalol following short-term oral treatment. In view of these observations, the use of dofetilide may be proposed also in patients with ventricular tachyarrhythmias associated with impaired left-ventricular function. Whether the haemodynamic differences between dofetilide and D,L-sotalol are the basis for differences in tolerability remains to be evaluated. 相似文献
80.
Bonfiglio G Simporè J Pignatelli S Musumeci S Solinas ML 《International journal of antimicrobial agents》2002,20(5):387-389
During 1999-2000 a total of 4131 faecal specimens were collected and analysed at the medical centre St. Camille at Ouagadougou. Eight hundred and twenty-six (8.0%) grew significant bacteria. Escherichia coli (35%), Salmonella spp. (15%) and Shigella spp. (10%) were most frequently isolated. A large number of E. coli strains were resistant to aminopenicillins (>90%) and cotrimoxazole (80%); for Yersinia spp the resistance was 80 and 25%, respectively. Norfloxacin was the most active antibiotic but was rarely used. The study showed that it is necessary to create antibiotic-resistance surveillance centres in developing countries so that therapy may be appropriate and the spread of antibiotic resistance to other developed countries via increased emigration may be reduced. 相似文献