Abstract 4804: Glycoproteomic analysis of lung cancer malignant pleural effusions identify glycosylated proteins being produced by metastatic tumor cells

Abstract

Abstract Malignant pleural effusions are produced in late stage metastatic lung cancer. We have obtained malignant pleural effusions from lung cancer patients. The specimens are separated into fluid and cells and the cells are grown in culture in a non-adherent manner. The original pleural effusion fluid and the conditioned media harvested from the tumor cells growing in culture are analyzed by glycoproteomic methods to identify glycosylated proteins being produced by the tumor cells. The cells are grown in culture with defined media in a non-adherent manner for an extended period of time to enrich for the tumor cell populations. These cells are phenotypically characterized for lung, epithelial and tumor markers by immunohistochemistry and/or flow cytometry. Conditioned media is collected from the growing cells and along with the original pleural effusion fluid and the tumor cells analyzed for glycosylated proteins using lectin chromatography followed by the use of glycomic and proteomic methods to analyze N- and O-linked glycans and proteins present in these samples. Our early results indicate that cancer glycosylated proteins CA125 (MUC16), MUC1 and fibronectin are present in the conditioned media samples obtained from the different pleural effusion tumor cell cultures that can also be measured in the original pleural effusion fluids. Not all pleural effusion tumor cells produce the same cancer biomolecules. Interestingly if the tumor cells produced CA125 (MUC16) in their culture media, CA125 was also detected in the original pleural effusion fluid confirming that the biomolecules in the fluid originated from the tumor cells. Another patient sample produced mostly MUC1, but much CA125. Fibronectin was also produced by these cells. Glycomic analysis of the samples shows an enrichment of certain glycan groups (high mannose, fucosylated and sialytic acid) in the conditioned media samples when compared with the original pleural effusion fluid samples showing that these glycan groups and the proteins to which they are attached originate from the tumor cells present in the malignant pleural effusions. The use of malignant pleural effusions from lung cancer patients provides us with an excellent opportunity to study metastatic tumor cells and their local environment without the need for scarce tissue specimens. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4804. doi:1538-7445.AM2012-4804