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.

ARL4C is associated with initiation and progression of lung adenocarcinoma and represents a therapeutic target

“…Six human lung adenocarcinoma cell lines, A549, H358, H441, HCC827, H1650 and H1975 cells, were purchased from the American Type Culture Collection (ATCC). A549 (G12S), H358 (G12C) and H441 (G12V) harbor the KRAS mutation . HCC827 (E746‐A750 deletion), H1650 (E746‐A750 deletion) and H1975 (L858R and T790M) harbor the EGFR mutation .…”

The Structure and Biological Function of CREG

“…siRNA-mediated knockdown of CREG inhibited cancer cell proliferation. In a SILAC (stable isotope labeling with amino acids in cell culture) proteomic study of non-small cell lung cancer cell lines, Clark et al (2016) found that CREG was highly expressed and closely correlated with K-Ras mutations in lung cancer cells. siRNA knockdown of K-Ras suppressed CREG expression, while depletion of CREG in the K-Ras mutant lung cancer cell lines inhibited proliferation.…”

Expression of SARS-COV-2 cell receptor gene ACE2 is associated with immunosuppression and metabolic reprogramming in lung adenocarcinoma based on bioinformatics analyses of gene expression profiles

“…5 A) including two transcription factors CREG1 and MECOM between TCGA and GSE40791 (Pearson's correlation test, FDR <0.05, R > 0.3). CREG1 has a potential role in cell proliferation and migration in NSCLC cells [ 51 ]. MECOM is significantly amplified in lung adenocarcinoma [ 10 ].…”