title: Glycoproteomic Approach Identifies KRAS as a Positive Regulator of CREG1 in Non-small Cell Lung Cancer Cells.
abstract: Protein glycosylation plays a fundamental role in a multitude of biological processes, and the associated aberrant expression of glycoproteins in cancer has made them attractive biomarkers and therapeutic targets. In this study, we examined differentially expressed glycoproteins in cell lines derived from three different states of lung tumorigenesis: an immortalized bronchial epithelial cell (HBE) line, a non-small cell lung cancer (NSCLC) cell line harboring a Kirsten rat sarcoma viral oncogene homolog (KRAS) activation mutation and a NSCLC cell line harboring an epidermal growth factor receptor (EGFR) activation deletion. Using a Triple SILAC proteomic quantification strategy paired with hydrazide chemistry N-linked glycopeptide enrichment, we quantified 118 glycopeptides in the three cell lines derived from 82 glycoproteins. Proteomic profiling revealed 27 glycopeptides overexpressed in both NSCLC cell lines, 6 glycopeptides overexpressed only in the EGFR mutant cells and 19 glycopeptides overexpressed only in the KRAS mutant cells. Further investigation of a panel of NSCLC cell lines found that Cellular repressor of E1A-stimulated genes (CREG1) overexpression was closely correlated with KRAS mutation status in NSCLC cells and could be down-regulated by inhibition of KRAS expression. Our results indicate that CREG1 is a down-stream effector of KRAS in a sub-type of NSCLC cells and a novel candidate biomarker or therapeutic target for KRAS mutant NSCLC.
authors.affiliation: 1. Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD ; 2. Marlene and Stewart Greenebaum Cancer Center, University of Maryland, Baltimore, MD.
authors.forename: David J
authors.initials: DJ
authors.lastname: Clark
authors.affiliation: 1. Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Mei
authors.affiliation: 3. Department of Pathology, John Hopkins University, Baltimore, MD.
authors.forename: Shisheng
authors.initials: S
authors.lastname: Sun
authors.affiliation: 3. Department of Pathology, John Hopkins University, Baltimore, MD.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: 2. Marlene and Stewart Greenebaum Cancer Center, University of Maryland, Baltimore, MD.
authors.forename: Austin J
authors.initials: AJ
authors.lastname: Yang
authors.affiliation: 1. Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD ; 2. Marlene and Stewart Greenebaum Cancer Center, University of Maryland, Baltimore, MD.
authors.forename: Li
authors.initials: L
authors.lastname: Mao
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology*; D045744:Cell Line, Tumor; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D020543:Proteome / Q000032:analysis*; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*
chemical_list: C114068:CREG1 protein, human; D006023:Glycoproteins; C117307:KRAS protein, human; D020543:Proteome; D012097:Repressor Proteins; D016283:Proto-Oncogene Proteins p21(ras)
keywords: KRAS; adenocarcinoma; glycoprotein; non-small cell lung cancer (NSCLC); quantitative glycoproteomics