In-depth proteomics to define the cell surface and secretome of ovarian cancer cells and processes of protein shedding

Abstract

Current proteomics technologies allow substantial depth of analysis of cellular and subcellular proteomes as shown in the proteomic profiling of ovarian cancer cells. This in-depth analysis has elucidated the repertoire of proteins expressed on the cell surface and proteins released into the extracellular milieu, uncovering extensive shedding of extracellular domains of cell adhesion proteins and a highly dynamic protein secretion process. The protein sets identified provide a rich resource of potential circulating markers and targets for imaging and therapeutics for ovarian cancer.

Figure 1

In-depth proteomic analysis of ovarian cancer cells. The overlap of protein identifications from cell lines and cancer cells obtained from patient ascites is significant, indicating good representation of ovarian cancer cells among cell lines. Analysis of proteins from the conditioned medium identified sequences spanning extracellular domains for transmembrane proteins. Sequences spanning intracellular domains were detected on the cell surface. These observations are consistent with a shedding process as indicated here for E-cadherin (CDH1).