Proteomic analysis of synaptosomal protein expression reveals that cerebral ischemia alters lysosomal Psap processing

Abstract

The aim of the present study was to determine whether combined administration of monoclonal antibody (Herceptin ® , trastuzumab) and anti-HER-2 (clone CB11) with hyaluronic acid (HA) and lipoplex (containing lipofectamine (LipA) and plasmid DNA) can produce a synergistic reaction to increase the therapeutic effect of monoclonal antibodies. To assess the treatment response, we cultured a 3-D MCF-7 cell line overexpressing HER-2 and CD44 receptors. The high density 3-D cell aggregation in the hollow fiber bioreactor (HFB) used for the cell culture was monitored with the use of proton magnetic resonance imaging ( 1 H MRI). In addition, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was used in combination with HPLC (high performance liquid chromatography) to evaluate structural changes in the proteins contained in treated cells. The study showed that incorporation of antibodies into targeted lipoplex results in more efficient delivery of the complex to tumor cells. The viability of cells decreased mostly due to cellular uptake of lipoplex and binding of the antibodies to the cellular surface receptor. The data also demonstrate that HA could be used to enhance treatment efficacy of trastuzumab and anti-HER-2 (clone CB11) in breast cancer cell cultures.

Cerebral Ischemia Induced Proteomic Alterations: Consequences for the Synapse and Organelles

“…7B). Consistent with our previous report (Costain et al 2010), approximately half (51%) of the IS dataset were mitochondrial proteins (Fig. 7B), whereas < 25% of known synaptosomal proteins are mitochondrial.…”

“…6). Consistent with our previous study, the majority of the IS proteins were localized in the mitochondria (Costain et al 2010), and the localization of the remaining proteins was consistent with the synaptic compartment. Furthermore, literature mining of PubMed indicated that only ≈ 15% of the IS proteins were associated with the MCAO model of cerebral ischemia.…”

“…Activation of a variety of proteases, such as members of the caspase, calpain and cathepsin families, is a well-described consequence of cerebral ischemia (Vanderklish & Bahr 2000, Kagedal et al 2001. Complicating this is the observation that cerebral ischemia causes proteosomal (DeGracia et al 2002), lysosomal (Costain et al 2010), mitochondrial (Costain et al 2010) and endoplasmic reticulum dysfunction (Ge et al 2007). Thus, it is almost impossible to predict post-ischemic cellular protein levels from gene expression data alone.…”

“…While the ICAT-based method exhibited a high quantitative reproducibility, quantitative accuracy, and a wide dynamic range (Costain et al 2010), it did not provide a very comprehensive analysis of the proteins. A comparison between the label-free and ICAT methods is shown in Table 3.…”

“…These results indicate that the observed expression and error values are due to biological effects. (Costain et al 2010) and both methods. (B) Venn diagram showing the overlap between the IS dataset using label-free proteomics (this study, 371 proteins) and the known synaptosomal proteins (1582 proteins) in the literature (Cheng et al 2006, Morciano et al 2005, Phillips et al 2005, Schrimpf et al 2005, Witzmann et al 2005, Jordan et al 2004, Peng et al 2004, Stevens et al 2003, Li et al 2004).…”