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1.
Oncogene ; 35(46): 5977-5988, 2016 11 17.
Article in English | MEDLINE | ID: mdl-27292262

ABSTRACT

Metastatic competence is contingent upon the aberrant activation of a latent embryonic program, known as the epithelial-mesenchymal transition (EMT), which bestows stem cell properties as well as migratory and invasive capabilities upon differentiated tumor cells. We recently identified the transcription factor FOXC2 as a downstream effector of multiple EMT programs, independent of the EMT-inducing stimulus, and as a key player linking EMT, stem cell traits and metastatic competence in breast cancer. As such, FOXC2 could serve as a potential therapeutic target to attenuate metastasis. However, as FOXC2 is a transcription factor, it is difficult to target by conventional means such as small-molecule inhibitors. Herein, we identify the serine/threonine-specific kinase p38 as a druggable upstream regulator of FOXC2 stability and function that elicits phosphorylation of FOXC2 at serine 367 (S367). Using an orthotopic syngeneic mouse tumor model, we make the striking observation that inhibition of p38-FOXC2 signaling selectively attenuates metastasis without impacting primary tumor growth. In this model, circulating tumor cell numbers are significantly reduced in mice treated with the p38 inhibitor SB203580, relative to vehicle-treated counterparts. Accordingly, genetic or pharmacological inhibition of p38 decreases FOXC2 protein levels, reverts the EMT phenotype and compromises stem cell attributes in vitro. We also identify the EMT-regulator ZEB1-known to directly repress E-cadherin/CDH1-as a downstream target of FOXC2, critically dependent on its activation by p38. Consistent with the notion that activation of the p38-FOXC2 signaling axis represents a critical juncture in the acquisition of metastatic competence, the phosphomimetic FOXC2(S367E) mutant is refractory to p38 inhibition both in vitro and in vivo, whereas the non-phosphorylatable FOXC2(S367A) mutant fails to elicit EMT and upregulate ZEB1. Collectively, our data demonstrate that FOXC2 regulates EMT, stem cell traits, ZEB1 expression and metastasis in a p38-dependent manner, and attest to the potential utility of p38 inhibitors as antimetastatic agents.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Forkhead Transcription Factors/metabolism , Serine/metabolism , Zinc Finger E-box-Binding Homeobox 1/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Antineoplastic Agents/pharmacology , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Disease Models, Animal , Epithelial-Mesenchymal Transition/genetics , Female , Heterografts , Humans , Mesenchymal Stem Cells/metabolism , Mice , Neoplasm Metastasis , Neoplastic Stem Cells/metabolism , Phenotype , Phosphorylation , Protein Binding , RNA, Small Interfering/genetics
2.
Arch Virol ; 161(9): 2431-40, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27339685

ABSTRACT

Intercellular spread of plant viruses involves passage of the viral genome or virion through a plasmodesma (PD). Some viruses severely modify the PD structure, as they assemble a virion carrying tubule composed of the viral movement protein (MP) inside the PD channel. Successful modulation of the host plant to allow infection requires an intimate interaction between viral proteins and both structural and regulatory host proteins. To date, however, very few host proteins are known to promote virus spread. Plasmodesmata-located proteins (PDLPs) localised in the PD have been shown to contribute to tubule formation in cauliflower mosaic virus and grapevine fanleaf virus infections. In this study, we have investigated the role of PDLPs in intercellular transport of another tubule-forming virus, cowpea mosaic virus. The MP of this virus was found to interact with PDLPs in the PD, as was shown for other tubule-forming viruses. Expression of PDLPs and MPs in protoplasts in the absence of a PD revealed that these proteins do not co-localise at the site of tubule initiation. Furthermore, we show that tubule assembly in protoplasts does not require an interaction with PDLPs at the base of the tubule, as has been observed in planta. These results suggest that a physical interaction between MPs and PDLPs is not required for assembly of the movement tubule and that the beneficial role of PDLPs in virus movement is confined to the structural context of the PD.


Subject(s)
Comovirus/physiology , Nicotiana/virology , Plant Proteins/metabolism , Plant Viral Movement Proteins , Plasmodesmata/physiology , Gene Expression Regulation, Plant/physiology , Plant Leaves/physiology , Plant Leaves/virology , Plant Proteins/genetics , Plants, Genetically Modified , Protein Transport , Nicotiana/genetics , Nicotiana/physiology
3.
Bone Joint J ; 96-B(6): 765-71, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24891576

ABSTRACT

We hypothesised there was no clinical value in using an autologous blood transfusion (ABT) drain in either primary total hip (THR) or total knee replacement (TKR) in terms of limiting allogeneic blood transfusions when a modern restrictive blood management regime was followed. A total of 575 patients (65.2% men), with a mean age of 68.9 years (36 to 94) were randomised in this three-arm study to no drainage (group A), or to wound drainage with an ABT drain for either six hours (group B) or 24 hours (group C). The primary outcome was the number of patients receiving allogeneic blood transfusion. Secondary outcomes were post-operative haemoglobin (Hb) levels, length of hospital stay and adverse events. This study identified only 41 transfused patients, with no significant difference in distribution between the three groups (p = 0.857). The mean pre-operative haemoglobin (Hb) value in the transfused group was 12.8 g/dL (9.8 to 15.5) versus 14.3 g/dL (10.6 to 18.0) in the non-transfused group (p < 0.001, 95% confidence interval: 1.08 to 1.86). Post-operatively, the median of re-transfused shed blood in patients with a THR was 280 mL (Interquartile range (IQR) 150 to 400) and in TKR patients 500 mL (IQR 350 to 650) (p < 0.001). ABT drains had no effect on the proportion of transfused patients in primary THR and TKR. The secondary outcomes were also comparable between groups.


Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Drainage/methods , Prosthesis-Related Infections/diagnosis , Prosthesis-Related Infections/therapy , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Arthroplasty, Replacement, Hip/methods , Arthroplasty, Replacement, Knee/methods , Blood Transfusion, Autologous/methods , Confidence Intervals , Female , Follow-Up Studies , Hip Prosthesis , Humans , Kaplan-Meier Estimate , Knee Prosthesis , Logistic Models , Male , Prosthesis Failure , Reoperation/methods , Risk Assessment , Transplantation, Homologous/methods , Treatment Outcome
4.
J Bone Joint Surg Br ; 90(9): 1205-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18757961

ABSTRACT

We evaluated 100 consecutive patients with a suspected scaphoid fracture but without evidence of a fracture on plain radiographs using MRI within 24 hours of injury, and bone scintigraphy three to five days after injury. The reference standard for a true radiologically-occult scaphoid fracture was either a diagnosis of fracture on both MRI and bone scintigraphy, or, in the case of discrepancy, clinical and/or radiological evidence of a fracture. MRI revealed 16 scaphoid and 24 other fractures. Bone scintigraphy showed 28 scaphoid and 40 other fractures. According to the reference standard there were 20 scaphoid fractures. MRI was falsely negative for scaphoid fracture in four patients and bone scintigraphy falsely positive in eight. MRI had a sensitivity of 80% and a specificity of 100%. Bone scintigraphy had a sensitivity of 100% and a specificity of 90%. This study did not confirm that early, short-sequence MRI was superior to bone scintigraphy for the diagnosis of a suspected scaphoid fracture. Bone scintigraphy remains a highly sensitive and reasonably specific investigation for the diagnosis of an occult scaphoid fracture.


Subject(s)
Fractures, Bone/diagnosis , Fractures, Closed/diagnosis , Scaphoid Bone/injuries , Adolescent , Adult , Aged , Aged, 80 and over , Diphosphonates , False Negative Reactions , False Positive Reactions , Female , Fractures, Bone/diagnostic imaging , Fractures, Closed/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prospective Studies , Radionuclide Imaging , Radiopharmaceuticals , Scaphoid Bone/diagnostic imaging , Sensitivity and Specificity
5.
Ned Tijdschr Geneeskd ; 151(13): 742-7, 2007 Mar 31.
Article in Dutch | MEDLINE | ID: mdl-17471775

ABSTRACT

An adequate management of scaphoid fractures requires fast and reliable diagnosis. In this, proper history taking and physical examination are essential. Routine scaphoid x-rays miss over 20% of all scaphoid fractures. Therefore, in patients with a clinically suspected scaphoid fracture that cannot be proven by scaphoid x-rays, further diagnostic investigation is indicated. Which supplemental diagnostic tool (bone scintigraphy, MRI, CT) is preferred remains unclear. A below-the-elbow cast without immobilisation of the thumb is an adequate treatment for stable fractures. Unstable fractures and all proximal pole fractures are candidates for open or percutaneous treatment. In addition to the type of fracture, patient-specific requirements are important in deciding which type of management is the most suitable.


Subject(s)
Fractures, Bone/diagnosis , Fractures, Bone/surgery , Scaphoid Bone/injuries , Humans , Physical Examination , Radiography , Scaphoid Bone/diagnostic imaging , Scaphoid Bone/surgery , Treatment Outcome
6.
Injury ; 38(7): 769-74, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17307177

ABSTRACT

UNLABELLED: Early diagnosis and treatment of scaphoid fractures limits the number of delayed and non-unions. Bone scintigraphy proved to be a sensitive diagnostic tool for the detection of occult scaphoid fractures. However, the results have to be interpreted with care. OBJECTIVE: To prospectively correlate the results of bone scintigraphy with clinical outcome. METHODS: In a prospective study, we analysed 50 consecutive patients with signs of a scaphoid fracture at physical examination but no evidence of a scaphoid fracture on scaphoid radiographs. All patients had a protocolised follow up at fixed intervals. The clinical outcome was defined according to a standardised algorithm. MAIN RESULTS: Bone scintigraphy revealed 32% (16/50) occult scaphoid fractures and 40% (20/50) occult other fractures. Clinical outcome proved that bone scintigraphy was false positive in five patients and in one case false negative for a scaphoid fracture. CONCLUSION: Bone scintigraphy in combination with protocolised physical examination is the gold standard for patients with signs of a scaphoid fracture that cannot be proven on scaphoid radiographs.


Subject(s)
Fractures, Bone/diagnostic imaging , Scaphoid Bone/injuries , Adult , Aged , Diphosphonates , Female , Humans , Male , Middle Aged , Prospective Studies , Radionuclide Imaging , Radiopharmaceuticals , Scaphoid Bone/diagnostic imaging , Technetium Compounds , Treatment Outcome
7.
J Hand Surg Br ; 31(4): 416-8, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16716469

ABSTRACT

Bone scintigraphy will identify up to 25% of occult scaphoid bone fractures after negative scaphoid X-rays. Consequently, it deserves a place in the diagnostic process of suspected scaphoid fractures. However, the role of bone scintigraphy is less clear if scaphoid X-rays show other fractures in the carpal region. We analysed 111 consecutive patients with a suspected scaphoid fracture on physical examination. Scaphoid X-rays revealed 61 fractures. Fifty-five patients had scaphoid fractures only and six patients had other fractures in the carpal region but no scaphoid fracture. In 50 cases, no bone injury was seen on these X-rays. In three out of the six patients with other fractures in the carpal region, bone scintigraphy revealed four occult concomitant fractures: one scaphoid, one scaphoid and trapezial and one capitate fracture. In conclusion, bone scintigraphy is required when scaphoid X-rays do not confirm a suspected scaphoid fracture, even in the presence of other fractures in the carpal region.


Subject(s)
Carpal Bones/injuries , Fractures, Bone/epidemiology , Scaphoid Bone/injuries , Carpal Bones/diagnostic imaging , Fractures, Bone/diagnostic imaging , Humans , Predictive Value of Tests , Radiography , Retrospective Studies , Scaphoid Bone/diagnostic imaging
8.
Injury ; 36(10): 1233-6, 2005 Oct.
Article in English | MEDLINE | ID: mdl-15979624

ABSTRACT

UNLABELLED: Undisplaced scaphoid fractures are easily missed on conventional scaphoid radiographs, but these occult fractures may seriously impair hand function. Routine bone scintigraphy (BS) is often advocated if there are clinical signs of a scaphoid fracture without radiological evidence. However, the results require careful therapeutic management. OBJECTIVE: To determine the diagnostic value of BS in daily practice for clinically suspected scaphoid fractures. METHODS: We evaluated our protocol of routine BS in suspected scaphoid fractures. SUBJECTS: In a retrospective study, we analysed 111 consecutive cases with signs of a scaphoid fracture on physical examination. Radiographs revealed 55 fractures, the remaining 56 patients all underwent BS. MAIN RESULTS: On average, the BS was performed after 4 days. It showed a fracture in 38/56 of the patients. The distribution of fractures was: scaphoid bone 15, distal radius 11, other carpal bones 9 and metacarpal bones 3. CONCLUSION: If there is a strong clinical suspicion of a scaphoid fracture, which cannot be confirmed by conventional radiology, BS is a valuable diagnostic tool.


Subject(s)
Fractures, Bone/diagnostic imaging , Scaphoid Bone/diagnostic imaging , Scaphoid Bone/injuries , Adolescent , Adult , Aged , Aged, 80 and over , Child , Clinical Protocols , Diphosphonates , False Negative Reactions , Female , Humans , Male , Middle Aged , Radiography , Radionuclide Imaging , Radiopharmaceuticals , Retrospective Studies , Technetium Compounds
9.
Clin Cancer Res ; 7(10): 3127-34, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11595705

ABSTRACT

PURPOSE: To better understand the role of G(1)-S transition regulator abnormalities in the pathogenesis of advanced premalignant lesions of the upper aerodigestive tract and the biological effects of chemoprevention, we studied biopsies obtained sequentially from participants in a prospective trial using 13-cis retinoic acid, IFN-alpha, and alpha-tocopherol for 12 months. EXPERIMENTAL DESIGN: Cyclin D1 and p16 expression were analyzed by immunohistochemistry, loss of heterozygosity by polymerase chain reacting amplification, and then electrophoretic separation of the products, methylation of the p16 promoter by methylation-specific polymerase chain reacting, and cyclin D1 gene amplification by fluorescence in situ hybridization. RESULTS: Baseline dysregulation of cyclin D1 expression was found in 50% (14 of 28) and was reversed in 6 of 14 cases, whereas p16 expression was lost in 46% (13 of 28) and regained in 2 of 13 cases. Loss of heterozygosity at 9p21 occurred in 68% and p16(INK4a) promoter methylation occurred in 75% of cases, with increasing frequency from mild to severe dysplasia. Cyclin D1 gene amplification was identified in two cases. Cyclin D1 protein dysregulation at last follow-up alone and in combination with p16 loss was associated with histological progression and cancer development (P < 0.01). CONCLUSIONS: Additional study of these alterations in a larger sample and exploration of the upstream signaling partners of these cell cycle regulators in vivo is warranted to identify cancer risk profiles that would be meaningful targets for chemopreventive intervention.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclins/genetics , Head and Neck Neoplasms/pathology , Precancerous Conditions/pathology , Adult , Aged , Cell Cycle Proteins/physiology , Chromosomes, Human, Pair 9/genetics , Cyclin D , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Cyclins/metabolism , DNA/genetics , DNA/metabolism , DNA Methylation , Female , Gene Expression Regulation , Head and Neck Neoplasms/prevention & control , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Loss of Heterozygosity , Male , Microsatellite Repeats , Middle Aged , Polymerase Chain Reaction/methods , Precancerous Conditions/genetics , Precancerous Conditions/metabolism
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