Global Impact of Oncogenic Src on a Phosphotyrosine Proteome

Department of Cell and Developmental Biology, Cancer Biology, Biostatistics, and Biochemistry, and The Proteomics Laboratory of the Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
Journal of Proteome Research (Impact Factor: 5). 07/2008; 7(8):3447-60. DOI: 10.1021/pr800187n
Source: PubMed

ABSTRACT Elevated activity of Src, the first characterized protein-tyrosine kinase, is associated with progression of many human cancers, and Src has attracted interest as a therapeutic target. Src is known to act in various receptor signaling systems to impact cell behavior, yet it remains likely that the spectrum of Src protein substrates relevant to cancer is incompletely understood. To better understand the cellular impact of deregulated Src kinase activity, we extensively applied a mass spectrometry shotgun phosphotyrosine (pTyr) proteomics strategy to obtain global pTyr profiles of Src-transformed mouse fibroblasts as well as their nontransformed counterparts. A total of 867 peptides representing 563 distinct pTyr sites on 374 different proteins were identified from the Src-transformed cells, while 514 peptides representing 275 pTyr sites on 167 proteins were identified from nontransformed cells. Distinct characteristics of the two profiles were revealed by spectral counting, indicative of pTyr site relative abundance, and by complementary quantitative analysis using stable isotope labeling with amino acids in cell culture (SILAC). While both pTyr profiles are replete with sites on signaling and adhesion/cytoskeletal regulatory proteins, the Src-transformed profile is more diverse with enrichment in sites on metabolic enzymes and RNA and protein synthesis and processing machinery. Forty-three pTyr sites (32 proteins) are predicted as major biologically relevant Src targets on the basis of frequent identification in both cell populations. This select group, of particular interest as diagnostic biomarkers, includes well-established Src sites on signaling/adhesion/cytoskeletal proteins, but also uncharacterized sites of potential relevance to the transformed cell phenotype.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Protein tyrosine phosphatases (PTPs) modulate the cellular level of tyrosine phosphorylation under normal and pathological conditions, and thus exert either stimulatory or inhibitory effect on signal transduction. Hence, PTPs are potential pharmacological targets for novel drugs being developed in order to treat numerous pathologies including cancer. For example, PTPs have been found to play a key role in pathogenesis of autoimmune disorders, allergic response, cardiovascular or neurodegenerative diseases, among others Alzheimer\'s disease. Moreover, since many PTPs fine-tune subtle regulation of microbial biochemistry controlling the viability and virulence, they can be candidates for new therapies of infection diseases. In this review, authors summarize the current knowledge on PTPs implication in etiopathogenesis of most common human diseases focusing on PTPs as potential therapeutical targets.
    Frontiers in Bioscience 01/2015; 20:377-88. · 4.25 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The membrane-anchored, non-receptor tyrosine kinase SRC is a critical regulator of signal transduction induced by a large variety of cell surface receptors, including Receptor Tyrosine kinases (RTK) that bind to growth factors to control cell growth and migration. When deregulated, SRC shows strong oncogenic activity, probably because of its capacity to promote RTK-mediated downstream signalling even in the absence of extracellular stimuli. Accordingly, SRC is frequently deregulated in human cancer and is thought to play important roles during tumourigenesis. However, our knowledge on the molecular mechanism by which SRC controls signalling is incomplete due to the limited number of key substrates identified so far. Here, we review how phosphoproteomic methods have changed our understanding of the mechanisms underlying SRC signalling in normal and tumour cells and discuss how these novel findings can be used to improve therapeutic strategies aimed at targeting SRC signalling in human cancer.This article is protected by copyright. All rights reserved
    Proteomics 11/2014; 15(2-3). DOI:10.1002/pmic.201400162 · 3.97 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Owing to recent advances in proteomics analytical methods coupled with bioinformatics capabilities there is a growing trend towards using these capabilities for the development of drugs to treat human disease, including target and drug evaluation, understanding mechanisms of action, and biomarker discovery. Currently the genetic sequences of many major organisms are available, which has helped greatly in characterizing proteomes in model animal systems and in humans. Through proteomics, global profiles of different disease states can be characterized (e.g. changes in types and relative levels as well as post-translational modifications such as glycosylation or phosphorylation). Although intracellular proteomics can provide a broad overview of physiology of cells and tissues, it has been difficult to quantify the low abundance proteins which can be important for understanding the diseased states and treatment progression. For this reason, there is increasing interest in coupling comparative proteomics methods with subcellular fractionation and enrichment techniques for membranes, nucleus, phosphoproteome, glycoproteome as well as low abundance serum proteins. In this review, we will provide examples of where the utilization of different proteomics-coupled enrichment techniques has aided target and biomarker discovery, understanding the targeting mechanism, and mAb discovery. Taken together, these improvements will help to provide a better understanding of the pathophysiology of various diseases including cancer, autoimmunity, inflammation, cardiovascular, and neurological conditions, and in the design and development of better medicines for treating these afflictions. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    PROTEOMICS - CLINICAL APPLICATIONS 02/2015; 9(1-2). DOI:10.1002/prca.201400097 · 2.68 Impact Factor

Full-text (2 Sources)

Available from
Jun 1, 2014