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71.
Multiple pathways of cell invasion are regulated by multiple families of serine proteases 总被引:5,自引:0,他引:5
Del Rosso M Fibbi G Pucci M D'Alessio S Del Rosso A Magnelli L Chiarugi V 《Clinical & experimental metastasis》2002,19(3):193-207
The complex process of tumor invasion requires the coordinated expression and activity of cell-substratum adhesive interactions
and of cell-associated protease systems, which destroy the extracellular matrix (ECM), in order to enable the invading cells
to simultaneously grip and destroy the anatomical barriers that control cell spreading. A number of data indicate that such
a `grip and go' process may be performed by an enlarging series of cell membrane-associated serine proteases and serine protease
receptors, which provide the invasive cells with a functional unit (the protease and its receptor), able to mediate cell-substratum
adhesion through specific receptor domains, to proteolytically degrade ECM and to deliver into the cell signals that up-regulate
the expression either of the protease/receptor complex, or of other adhesion molecules, such as integrins. There is evidence
that some proteases and protease receptor expression are under the control of tumor hypoxia, which is the result of an imbalance
in oxygen supply and demand. The urokinase-type plasminogen activator (u-PA) receptor (u-PAR) is under hypoxic control and
cooperates with other serine proteases of the blood coagulation pathways that may extravasate in the tumor milieu as a result
of hypoxia-simulated increase of vessel permeability. Other serine proteases and their receptors cooperate with the cell-associated
fibrinolytic system to promote cell invasion. Among these, tissue factor and its ligand coagulation factor VII, thrombin and
its protease-activated receptors, and type II trans-membrane serine proteases seem to play a crucial role. This Review takes
into consideration the complex scenario of the single serine proteases and related receptors that are involved in cell invasion,
as well as the protease receptor/adhesion molecule interplay which is necessary to focus the cell surface-driven proteolysis
where adhesion provides a grip to the invading cell.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
72.
Paradiso A Abatangelo M Piepoli S Tommasi S Xu JM Caponio MA Marzullo F D'Auria C Achille G Grammatica L 《Cancer Genetics and Cytogenetics》2002,132(2):141-144
Oncogene alterations have been clearly demonstrated to be related to the carcinogenesis and progression of oral squamous cell carcinoma (OSCC). However, the analysis of these alterations for screening and early diagnostic purposes generally requires invasive techniques for surgical removal of pathological epithelium. The aim of the present study was to assess the feasibility of fluorescence in situ hybridization (FISH) analysis of HER-2/neu amplification in oral mucosa brushings and to compare the HER-2/neu status with the history and smoking and drinking habits of healthy subjects. Cells obtained by centrifugation of oral brushings from 21 subjects (overall no. of cells: 5125) were suspended in physiological saline and fixed onto two slides for cytological evaluation and FISH analysis (dual-target, dual-color fluorescence assay) of the HER-2/neu gene and CEP17 centromere. A mean of 89.8% of the cells showed two HER-2/neu signals and a mean of 94% had two CEP17 signals at fluorescent microscopy. Finally, a mean of 96% of cells with HER-2/neu / CEP17 had a ratio equal to 1. No association between smoking and drinking habits, age and the HER-2/neu and CEP17 characteristics evaluated by FISH was found. 相似文献
73.
Kimura T Nakamori M Lueck JD Pouliquin P Aoike F Fujimura H Dirksen RT Takahashi MP Dulhunty AF Sakoda S 《Human molecular genetics》2005,14(15):2189-2200
Myotonic dystrophy type 1 (DM1) is a debilitating multisystemic disorder caused by a CTG repeat expansion in the DMPK gene. Aberrant splicing of several genes has been reported to contribute to some symptoms of DM1, but the cause of muscle weakness in DM1 and elevated Ca2+ concentrations in cultured DM muscle cells is unknown. Here, we investigated the alternative splicing of mRNAs of two major proteins of the sarcoplasmic reticulum, the ryanodine receptor 1 (RyR1) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) 1 or 2. The fetal variants, ASI(-) of RyR1 which lacks residue 3481-3485, and SERCA1b which differs at the C-terminal were significantly increased in skeletal muscles from DM1 patients and the transgenic mouse model of DM1 (HSA(LR)). In addition, a novel variant of SERCA2 was significantly decreased in DM1 patients. The total amount of mRNA for RyR1, SERCA1 and SERCA2 in DM1 and the expression levels of their proteins in HSA(LR) mice were not significantly different. However, heterologous expression of ASI(-) in cultured cells showed decreased affinity for [3H]ryanodine but similar Ca2+ dependency, and decreased channel activity in single-channel recording when compared with wild-type (WT) RyR1. In support of this, RyR1-knockout myotubes expressing ASI(-) exhibited a decreased incidence of Ca2+ oscillations during caffeine exposure compared with that observed for myotubes expressing WT-RyR1. We suggest that aberrant splicing of RyR1 and SERCA1 mRNAs might contribute to impaired Ca2+ homeostasis in DM1 muscle. 相似文献
74.
Alkuraya FS Lin AE Irons MB Kimonis VE 《American journal of medical genetics. Part A》2005,(2):226-230
Fryns syndrome is an autosomal recessive multiple congenital anomaly/mental retardation syndrome characterized by coarse face, distal limb hypoplasia, and diaphragmatic anomalies. We describe a newborn girl with Fryns syndrome and Hirschsprung disease, an association that has been reported in five previous cases. These patients support the hypothesis that the neural crest plays a role in the pathogenesis of Fryns syndrome. Clinically asymptomatic or subtle anomalies that are in the spectrum of neural crest maldevelopment should be sought in all patients with Fryns syndrome including stillbirths, neonatal deaths, as well as long-term survivors. We suspect that the clinical observation about Hirschsprung disease and Fryns syndrome may provide insight into its molecular mechanisms and candidate genes. 相似文献
75.
Regan N Theiler Angela M Caliendo Sabine Pargman B Denise Raynor Sarah Berga Melissa McPheeters Denise J Jamieson 《Journal of clinical virology》2006,37(4):313-316
BACKGROUND: Cytomegalovirus (CMV) infection, which is the most common congenitally transmitted infection, affects approximately 1% of neonates worldwide. Despite its prevalence, no convenient screening test for neonatal CMV infection has been implemented. OBJECTIVE: The purpose of this pilot study was to evaluate the feasibility and yield of screening umbilical cord blood for CMV DNA emiaby quantitative PCR. STUDY DESIGN: Umbilical cord blood was tested for CMV DNAemia using a commercial quantitative PCR assay. Maternal CMV serostatus at the time of delivery was assessed by testing for CMV IgG and IgM antibodies in serum. CONCLUSIONS: Screening for congenital CMV infection with PCR is easily incorporated into routine labor and delivery care using discarded cord blood specimens to identify neonates whose infection is otherwise undiagnosed. Among 433 infants tested, two (0.5%) had DNAemia detected in cord blood, one of whom was symptomatic, and both of whose mothers were CMV IgG positive and IgM negative. Viremic neonates identified by screening with PCR may be at high risk of developing long-term neurological complications of CMV infection and cannot reliably be identified using clinical presentation or maternal serology. Because of its convenience, cord blood CMV screening with PCR should be further investigated for incorporation into neonatal screening protocols. 相似文献
76.
Alexander Rodewald Rainer Pankau Angela Gosch Armin Wessel 《American journal of medical genetics. Part A》1994,53(3):227-235
The dermatoglyphic patterns of fingertips and palms of 115 patients with Williams-Beuren syndrome (WBS) were analysed and compared with the data from 199 control individuals from Germany. The following combination of dermatoglyphic patterns appears to be characteristic to WBS: an excess of whorls on all fingertips; high termination values of the main lines D, B, and A; frequent absence of C triradius (C°); high frequencies of ulnar loops on the hypothenar and distal loops on the 2nd, 3rd, and 4th inter digital areas, of distal axial triradii t", and of abnormal palmar creases such as simian crease and Sydney lines. The combination of fingertip and palmar patterns expressed by a “Log.Score-Index,” provides a high degree of discrimination between the WBS patients (92%) and the control group (88%). A “phantom picture” for WBS was constructed, which can be used for its diagnosis. © 1994 Wiley-Liss, Inc. 相似文献
77.
Angela Simpson Karla Arruda Martin Chapman 《Clinical reviews in allergy & immunology》1997,15(4):461-469
Conclusions Asthma can occur as a result of allergy to both house dust mites and to storage mites. Many people worldwide are exposed to
more than one mite species in the domestic environment. The most common domestic mites areD. pteronyssinus, D. farinae, E. maynei, andB. tropicalis; other storage mites are found in homes much less frequently, even in tropical climates. Because of the ready availability
of allergen extracts for skin testing and immunotherapy, patients with respiratory symptoms are generally evaluated for sensitization
toD. pteronyssinus andD. farinae only. The evidence reviewed here suggests, however, that, although there are crossreactive allergens between many mite species,
most species have specific allergens that can be an important cause of IgE responses. Therefore, the role ofB. tropicalis andE. maynei in the etiology of asthma merits further investigation. Identification of species-specific and crossreactive allergens and
production of recombinant allergens would be useful tools in allergy practice. By skin-testing patients, physicians would
then be able to evaluate whether patients recognize crossreactive allergens or species-specific allergens and whether or not
there is a need for immunotherapy to more than one mite species. 相似文献
78.
Pnina Fishman Emily Falach-Vaknin Benjamin Sredni Piere Luigi Meroni Angela Tincani Dror Dicker Yehuda Shoenfeld 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(2):80-84
PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE2), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE2 acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS. 相似文献
79.
80.
Dawson Luke P. Dinh Diem T. Stub Dion Ahern Susannah Bloom Jason E. Duffy Stephen J. Lefkovits Jeffrey Brennan Angela Reid Christopher M. Oqueli Ernesto 《Quality of life research》2022,31(8):2375-2385
Quality of Life Research - During the COVID-19 pandemic, widespread public health measures were implemented to control community transmission. The association between these measures and... 相似文献