title: A Multiplexed Cytokeratin Analysis Using Targeted Mass Spectrometry Reveals Specific Profiles in Cancer-Related Pleural Effusions.
abstract: Pleural effusion (PE), excess fluid in the pleural space, is often observed in lung cancer patients and also forms due to many benign ailments. Classifying it quickly is critical, but this remains an analytical challenge often lengthening the diagnosis process or exposing patients to unnecessary risky invasive procedures. We tested the analysis of PE using a multiplexed cytokeratin (CK) panel with targeted mass spectrometry-based quantitation for its rapid classification. CK markers are often assessed in pathological examinations for cancer diagnosis and guiding treatment course. We developed methods to simultaneously quantify 33 CKs in PE using peptide standards for increased analytical specificity and a simple CK enrichment method to detect their low amounts. Analyzing 121 PEs associated with a variety of lung cancers and noncancerous causes, we show that abundance levels of 10 CKs can be related to PE etiology. CK-6, CK-7, CK-8, CK-18, and CK-19 were found at significantly higher levels in cancer-related PEs. Additionally, elevated levels of vimentin and actin differentiated PEs associated with bacterial infections. A classifier algorithm effectively grouped PEs into cancer-related or benign PEs with 81% sensitivity and 79% specificity. A set of undiagnosed PEs showed that our method has potential to shorten PE diagnosis time. For the first time, we show that a cancer-relevant panel of simple-epithelial CK markers currently used in clinical assessment can also be quantitated in PEs. Additionally, while requiring less invasive sampling, our methodology demonstrated a significant ability to identify cancer-related PEs in clinical samples and thus could improve patient care in the future.
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland. Electronic address: dom.domanski@ibb.waw.pl.
authors.forename: Dominik
authors.initials: D
authors.lastname: Domanski
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Perzanowska
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland.
authors.forename: Michal
authors.initials: M
authors.lastname: Kistowski
authors.affiliation: Mazovian Center of Pulmonary Disease and Tuberculosis Treatment, Gabriela Narutowicza 80, Otwock, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Wojtas
authors.affiliation: Mazovian Center of Pulmonary Disease and Tuberculosis Treatment, Gabriela Narutowicza 80, Otwock, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Michalak
authors.affiliation: Mazovian Center of Pulmonary Disease and Tuberculosis Treatment, Gabriela Narutowicza 80, Otwock, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Krasowski
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland. Electronic address: michald@ibb.waw.pl.
authors.forename: Michal
authors.initials: M
authors.lastname: Dadlez
mesh_terms: D000199:Actins / Q000378:metabolism*; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007633:Keratins / Q000032:analysis* / Q000145:classification / Q000378:metabolism; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D010996:Pleural Effusion / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D014746:Vimentin / Q000378:metabolism*
chemical_list: D000199:Actins; D014408:Biomarkers, Tumor; D014746:Vimentin; D007633:Keratins