Proteomic Signatures of Thymomas.
Based on the histological features and outcome, the current WHO classification separates thymomas into A, AB, B1, B2 and B3 subtypes. It is hypothesized that the type A thymomas are derived from the thymic medulla while the type B thymomas are derived from the cortex. Due to occasional histological overlap between the tumor subtypes creating difficulties in their separation, the aim of this study was to provide their proteomic characterization and identify potential immunohistochemical markers aiding in tissue diagnosis. Pair-wise comparison of neoplastic and normal thymus by liquid chromatography tandem mass spectrometry (LC-MS/MS) of formalin fixed paraffin embedded tissue revealed 61 proteins differentially expressed in thymomas compared to normal tissue. Hierarchical clustering showed distinct segregation of subtypes AB, B1 and B2 from that of A and B3. Most notably, desmoyokin, a protein that is encoded by the AHNAK gene, was associated with type A thymomas and medulla of normal thymus, by LC-MS/MS and immunohistochemistry. In this global proteomic characterization of the thymoma, several proteins unique to different thymic compartments and thymoma subtypes were identified. Among differentially expressed proteins, desmoyokin is a marker specific for thymic medulla and is potentially promising immunohistochemical marker in separation of type A and B3 thymomas.
Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America.|The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States of America.
Linan
L
Wang
Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America.|The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States of America.
Owen E
OE
Branson
Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America.
Konstantin
K
Shilo
Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America.
Charles L
CL
Hitchcock
Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America.|The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States of America.
Michael A
MA
Freitas
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins / Q000032:analysis*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D020543:Proteome / Q000032:analysis*; D040901:Proteomics; D013601:T-Lymphocytes / Q000473:pathology; D053719:Tandem Mass Spectrometry; D013945:Thymoma / Q000473:pathology*; D013950:Thymus Gland / Q000473:pathology*; D013953:Thymus Neoplasms / Q000473:pathology*; D055815:Young Adult
C075176:AHNAK protein, human; D014408:Biomarkers, Tumor; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D020543:Proteome