Mass spectrometry-based quantitative analysis for decoding site-specific alteration of Sialo-glycoproteome in EGFR-subtype of non-small cell lung cancers

摘要

Altered protein sialylation of cell surfaces has been correlated with cancer development. Due to site hetergeneity, variable branching and extension of carbohydrates, intac glycopeptide analysis by mass spectrometry to fully decode the complex site-specific glycan structure on glycoproteins still presents great analytical challenges. Many studies have used label-free, isotopic labeling, or targeted multiple reaction monitoring method to quantify the glycoprotein after deglycosylation. Dirct measurement of altered glycoforms on specific glycosylation sites on proteins is intangible. A quantitative approach for identification and quantitation of intact glycopeptides and its glycosylation occupancy in different sample sources is also needed to delineate. Here, we apply isotopic labeling quantitative approach to decode the altered sialo-glycopeptides in different EGFR subtypes of non-small cell lung cancer cells.