Glycoproteomics using fluid-based specimens in the discovery of lung cancer protein biomarkers: Promise and challenge

Department of Pathology, the Johns Hopkins Medical Institutions, Baltimore, MD, 21287.
PROTEOMICS - CLINICAL APPLICATIONS (Impact Factor: 2.96). 10/2012; 7(1-2). DOI: 10.1002/prca.201200105
Source: PubMed


Lung cancer is the number one cancer in the US and worldwide. In spite of the rapid progression in personalized treatments, the overall survival rate of lung cancer patients is still suboptimal. Over the past decade, tremendous efforts have been focused on the discovery of protein biomarkers to facilitate the early detection and monitoring lung cancer progression during treatment. In addition to tumor tissues and cancer cell lines, a variety of biological material has been studied. Particularly in recent years, studies using fluid-based specimen or so-called "fluid-biopsy" specimen have progressed rapidly. Fluid specimens are relatively easier to collect than tumor tissue, and they can be repeatedly sampled during the disease progression. Glycoproteins have long been recognized to play fundamental roles in many physiological and pathological processes. In this review, we focus the discussion on recent advances of glycoproteomics, particularly in the identification of potential protein biomarkers using so-called fluid-based specimens in lung cancer. The purpose of this review is to summarize current strategies, achievements and perspectives in the field. This insight will highlight the discovery of tumor-associated glycoprotein biomarkers in lung cancer and their potential clinical applications.

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    • "In lung tissue, protein expression directly reflects the physiological and/or pathological status of the lung parenchyma [9-12]. Several recent studies have discovered that many proteins are differentially expressed in lung cancers [13-18]. The complex protein changes and/or signature of protein expression, particularly those associated with NSCLC, still need to be further defined. "
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