ADAM15 mediates upregulation of Claudin-1 expression in breast cancer cells

A Disintegrin and Metalloproteinase-15 (ADAM15) is a transmembrane protein involved in protein ectodomain shedding, cell adhesion and signalling. We previously cloned and characterised alternatively spliced variants of ADAM15 that differ in their intracellular domains and demonstrated correlation of the expression of specific variants with breast cancer prognosis. In this study we have created isogenic cell panels (MDA-MB-231 and MCF-7) expressing five ADAM15 variants including wildtype and catalytically inactive forms. The expression of ADAM15 isoforms in MDA-MB-231 cells led to cell clustering to varying degree, without changes in EMT markers vimentin, slug and E-cadherin. Analysis of tight junction molecules revealed ADAM15 isoform specific, catalytic function dependent upregulation of Claudin-1. The expression of ADAM15A, and to a lesser degree of C and E isoforms led to an increase in Claudin-1 expression in MDA-MB-231 cells, while ADAM15B had no effect. In MCF-7 cells, ADAM15E was the principal variant inducing Claudin-1 expression. Sh-RNA mediated down-regulation of ADAM15 in ADAM15 over-expressing cells reduced Claudin-1 levels. Additionally, downregulation of endogenous ADAM15 expression in T47D cells by shRNA reduced endogenous Claudin-1 expression confirming a role for ADAM15 in regulating Claudin-1 expression. The PI3K/Akt/mTOR pathway was involved in regulating Claudin-1 expression downstream of ADAM15. Immunofluorescence analysis of MDA-MB-231 ADAM15A expressing cells showed Claudin-1 at cell-cell junctions, in the cytoplasm and nuclei. ADAM15 co-localised with Claudin-1 and ZO1 at cell-cell junctions. Immunoprecipitation analysis demonstrated complex formation between ADAM15 and ZO1/ZO2. These findings highlight the importance of ADAM15 Intra Cellular Domain-mediated interactions in regulating substrate selection and breast cancer cell phenotype

ADAM15 mediates upregulation of Claudin-1 expression in breast cancer cells

A Disintegrin and Metalloproteinase-15 (ADAM15) is a transmembrane protein involved in protein ectodomain shedding, cell adhesion and signalling. We previously cloned and characterised alternatively spliced variants of ADAM15 that differ in their intracellular domains and demonstrated correlation of the expression of specific variants with breast cancer prognosis. In this study we have created isogenic cell panels (MDA-MB-231 and MCF-7) expressing five ADAM15 variants including wild-type and catalytically inactive forms. The expression of ADAM15 isoforms in MDA-MB-231 cells led to cell clustering to varying degree, without changes in EMT markers vimentin, slug and E-cadherin. Analysis of tight junction molecules revealed ADAM15 isoform specific, catalytic function dependent upregulation of Claudin-1. The expression of ADAM15A, and to a lesser degree of C and E isoforms led to an increase in Claudin-1 expression in MDA-MB-231 cells, while ADAM15B had no effect. In MCF-7 cells, ADAM15E was the principal variant inducing Claudin-1 expression. Sh-RNA mediated down-regulation of ADAM15 in ADAM15 over-expressing cells reduced Claudin-1 levels. Additionally, downregulation of endogenous ADAM15 expression in T47D cells by shRNA reduced endogenous Claudin-1 expression confirming a role for ADAM15 in regulating Claudin-1 expression. The PI3K/Akt/mTOR pathway was involved in regulating Claudin-1 expression downstream of ADAM15. Immunofluorescence analysis of MDA-MB-231 ADAM15A expressing cells showed Claudin-1 at cell-cell junctions, in the cytoplasm and nuclei. ADAM15 co-localised with Claudin-1 and ZO1 at cell-cell junctions. Immunoprecipitation analysis demonstrated complex formation between ADAM15 and ZO1/ZO2. These findings highlight the importance of ADAM15 Intra Cellular Domain-mediated interactions in regulating substrate selection and breast cancer cell phenotype

Analysis of deep tissue hypersensitivity to pressure pain in professional pianists with insidious mechanical neck pain

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate whether pressure pain hyperalgesia is a feature of professional pianists suffering from neck pain as their main playing-related musculoskeletal disorder.</p> <p>Methods</p> <p>Twenty-three active expert pianists, 6 males and 17 females (age: 36 ± 12 years) with insidious neck pain and 23 pianists, 9 males and 14 females (age: 38 ± 10 years) without neck pain the previous year were recruited. A numerical pain rate scale, Neck Disability Index, hand size and pressure pain thresholds (PPT) were assessed bilaterally over the C5-C6 zygapophyseal joint, deltoid muscle, the second metacarpal and the tibialis anterior muscle in a blinded design.</p> <p>Results</p> <p>The results showed that PPT levels were significantly decreased bilaterally over the second metacarpal and tibialis anterior muscles (P < 0.05), but not over C5-C6 zygapophyseal joint and deltoid muscle (P > 0.10), in pianists with neck pain as compared to healthy pianists. Pianists with neck pain had a smaller (P < 0.05) hand size (mean: 181.8 ± 11.8) as compared to pianists without neck pain (mean: 188. 6 ± 13.1). PPT over the tibialis anterior muscles was negatively correlated with the intensity of neck pain.</p> <p>Conclusions</p> <p>Our findings revealed pressure pain hypersensitivity over distant non-symptomatic distant points but not over the symptomatic areas in pianists suffering from neck pain. In addition, pianists with neck pain also had smaller hand size than those without neck pain. Future studies are needed to further determine the relevance of these findings in the clinical course of neck pain as playing-related musculoskeletal disorder in professional pianists.</p

Long-term survival of GSB III elbow prostheses and risk factors for revisions

INTRODUCTION: Although replacement of the elbow joint is a complex procedure there is not much clinical evidence that contributes to surgical decision-making, mainly due to small clinical samples and short follow-up. Therefore, we performed a long-term analysis up to 30 years after implantation of a GSB III total elbow prosthesis to quantify long-term outcome and to identify possible risk factors for implant revision. MATERIALS AND METHODS: All patients who received a primary GSB III total elbow prosthesis between 1978 and 1998 were included. Information about patient characteristics, the latest known implant status and possible risk factors were collected, Kaplan-Meier survival curves plotted, and 10- and 20-year survival calculated. The cohort was stratified for known risk factors such as diagnosis, age, or gender and included in a Cox regression analysis. RESULTS: A total of 253 patients [mean age at operation 56.9 years (range from 17.5 to 84 years)] with 293 GSB III prostheses were included. The median follow-up was 9.1 years (0 months to 29.3 years). Whereas 81 prostheses did not need revision during the observation period, 76 had been implanted in patients who died before any revision was required, and 75 had not been revised by the last known follow-up. 61 prostheses were revised. This corresponds to a 10-year survival rate of 0.8 (95 % CI 0.74-0.85) and a 20-year rate of 0.67 (95 % CI 0.57-0.76). Prostheses in patients with post-traumatic conditions survived significantly shorter than those in patients with rheumatoid arthritis; previous operations lead to a 2.8 times greater risk of revision (p = 0.004). Neither age at implantation nor gender had a significant influence on prosthesis survival. CONCLUSIONS: The results indicate a good long-term prognosis for this design. The prognosis has to be adjusted for the underlying disease. Previous operations such as joint reconstruction significantly increase the risk of revision