Search results for " PROTEOMICS"
showing 10 items of 140 documents
Building high-quality assay libraries for targeted analysis of SWATH MS data
2015
Targeted proteomics by selected/multiple reaction monitoring (S/MRM) or, on a larger scale, by SWATH (sequential window acquisition of all theoretical spectra) MS (mass spectrometry) typically relies on spectral reference libraries for peptide identification. Quality and coverage of these libraries are therefore of crucial importance for the performance of the methods. Here we present a detailed protocol that has been successfully used to build high-quality, extensive reference libraries supporting targeted proteomics by SWATH MS. We describe each step of the process, including data acquisition by discovery proteomics, assertion of peptide-spectrum matches (PSMs), generation of consensus sp…
C7 is expressed on endothelial cells as a trap for the assembling terminal complement complex and may exert anti-inflammatory function.
2009
AbstractWe describe a novel localization of C7 as a membrane-bound molecule on endothelial cells (ECs). Data obtained by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), Western blot analysis, Northern blot analysis, and mass spectrometry revealed that membrane-associated C7 (mC7) was indistinguishable from soluble C7 and was associated with vimentin on the cell surface. mC7 interacted with the other late complement components to form membrane-bound TCC (mTCC). Unlike the soluble SC5b-9, mTCC failed to stimulate ECs to express adhesion molecules, to secrete IL-8, and to induce albumin leakage through a monolayer of ECs, and more importantly protected ECs from the proinf…
The substrate degradome of meprin metalloproteases reveals an unexpected proteolytic link between meprin β and ADAM10
2012
The in vivo roles of meprin metalloproteases in pathophysiological conditions remain elusive. Substrates define protease roles. Therefore, to identify natural substrates for human meprin α and β we employed TAILS (terminal amine isotopic labeling of substrates), a proteomics approach that enriches for N-terminal peptides of proteins and cleavage fragments. Of the 151 new extracellular substrates we identified, it was notable that ADAM10 (a disintegrin and metalloprotease domain-containing protein 10)—the constitutive α-secretase—is activated by meprin β through cleavage of the propeptide. To validate this cleavage event, we expressed recombinant proADAM10 and after preincubation with meprin…
Targeted Therapy Modulates the Secretome of Cancer-Associated Fibroblasts to Induce Resistance in HER2-Positive Breast Cancer
2021
The combination of trastuzumab plus pertuzumab plus docetaxel as a first-line therapy in patients with HER2-positive metastatic breast cancer has provided significant clinical benefits compared to trastuzumab plus docetaxel alone. However, despite the therapeutic success of existing therapies targeting HER2, tumours invariably relapse. Therefore, there is an urgent need to improve our understanding of the mechanisms governing resistance, so that specific therapeutic strategies can be developed to provide improved efficacy. It is well known that the tumour microenvironment (TME) has a significant impact on cancer behaviour. Cancer-associated fibroblasts (CAFs) are essential components of the…
S100S PROTEIN EXPRESSION IN A LARGE SAMPLE-SET OF BREAST CANCER TISSUES
2010
S100 proteins are low molecular weight proteins ranging in size from 9 to 13 kDa. They form homo- and heterodimers and even oligomers and are expressed in tissue and cell-specific manner [1]. It is well documented, infact, that S100 proteins have a broad range of intracellular and extracellular functions. Intracellular functions include regulation of protein phosphorylation, enzyme activity, calcium homeostasis, regulation of cytoskeletal components and regulation of transcriptional factors, so they are involved in several biological processes including cell cycle regulation, cell growth, cell differentiation, and motility [2]. Extracellularly they act in a cytokine like manner through the …
Occurrence of S100A7 in a large sample-set of breast cancer tissues
2010
Differential occurrence of S100A7 in breast cancer tissues: A proteomic-based investigation
2012
Purpose The present study reports for the first time a large-scale proteomic screening of the occurrence, subcellular localization and relative quantification of the S100A7 protein among a group of 100 patients, clinically grouped for the diagnosis of infiltrating ductal carcinoma (IDC). Experimental design To this purpose, the methods of differential proteomics, Western blotting, and immunohistochemistry were used. Results The identity of two isoforms of the protein was assessed by mass spectrometry and immunologically confirmed. Moreover, we proved by immunocytochemical applications the exclusive localization of the protein within the neoplastic cells. The correlation of S100A7 expression…