Anti-CLU (aa 436-449) polyclonal antibody

It has been drawn attention that secreted proteins with signal peptide from cancer cells provide new potential biomarkers of cancer. In this study, three lung adenocarcinoma cell lines and serum samples from 20 patients were used for identifying potential serologic tumor biomarker with proteomic and bioinformatics approaches. One-dimensional electrophoresis, and identified with mass spectrometry and database research were performed. We found17 secreted proteins in common, while another 17 proteins with signal peptide were identified in all three lung adenocarcinoma cell lines alone with patient samples. With matching these two groups of identified proteins, calsyntenin-1 (CLSTN1), clusterin (CLU) and neutrophil gelatinase-associated lipocalin (NGAL) were found highly secreted from both cell lines and serum with unique signal peptides. Therefore, in our study, we demonstrated that cancer cells secret specific proteins to the environment that may serve as unique markers for cancer diagnosis. To combination of proteomic study with bioinformatic prediction on signal peptides, higher expression level of CLSTN1, CLU and NGAL were found and may be new solid serologic biomarkers for patients with lung adenocarcinoma.

Clusterin (CLU) or APOJ is a multifunctional glycoprotein that has been implicated in several physiological and pathological states, including Alzheimer's disease (AD). With a prominent extracellular chaperone function, additional roles have been discussed for clusterin, including lipid transport and immune modulation, and it is involved in pathways common to several diseases such as cell death and survival, oxidative stress, and proteotoxic stress. Although clusterin is normally a secreted protein, it has also been found intracellularly under certain stress conditions. Multiple hypotheses have been proposed regarding the origin of intracellular clusterin, including specific biogenic processes leading to alternative transcripts and protein isoforms, but these lines of research are incomplete and contradictory. Current consensus is that intracellular clusterin is most likely to have exited the secretory pathway at some point or to have re-entered the cell after secretion. Clusterin's relationship with amyloid beta (A beta) has been of great interest to the AD field, including clusterin's apparent role in altering A beta aggregation and/or clearance. Additionally, clusterin has been more recently identified as a mediator of A beta toxicity, as evidenced by the neuroprotective effect of CLU knockdown and knockout in rodent and human iPSC-derived neurons. CLU is also the third most significant genetic risk factor for late onset AD and several variants have been identified in CLU. Although the exact contribution of these variants to altered AD risk is unclear, some have been linked to altered CLU expression at both mRNA and protein levels, altered cognitive and memory function, and altered brain structure. The apparent complexity of clusterin's biogenesis, the lack of clarity over the origin of the intracellular clusterin species, and the number of pathophysiological functions attributed to clusterin have all contributed to the challenge of understanding the role of clusterin in AD pathophysiology. Here, we highlight clusterin's relevance to AD by discussing the evidence linking clusterin to AD, as well as drawing parallels on how the role of clusterin in other diseases and pathways may help us understand its biological function(s) in association with AD.