Proteomic mapping of p53 immunogenicity in pancreatic, ovarian, and breast cancers.
Mutations in TP53 induce autoantibody immune responses in a subset of cancer patients, which have been proposed as biomarkers for early detection. Here, we investigate the association of p53-specific autoantibodies with multiple tumor subtypes and determine the association with p53 mutation status and epitope specificity.



IgG p53 autoantibodies (p53-AAb), were quantified in 412 serum samples using a programmable ELISA assay from patients with serous ovarian, pancreatic adenocarcinoma, and breast cancer. To determine if patients generated mutation-specific autoantibodies we designed a panel of the most relevant 51 p53 point mutant proteins, to be displayed on custom programmable protein microarrays. To determine the epitope specificity we displayed 12 overlapping tiling fragments and 38 N- and C-terminal deletions spanning the length of the wild-type p53 protein.



We detected p53-AAb with sensitivities of 58.8% (ovarian), 22% (pancreatic), 32% (triple negative breast cancer), and 10.2% (HER2+ breast cancer) at 94% specificity. Sera with p53-AAb contained broadly reactive autoantibodies to 51 displayed p53 mutant proteins, demonstrating a polyclonal response to common epitopes. All p53-AAb displayed broad polyclonal immune response to both continuous and discontinuous epitopes at the N- and C-terminus as well as the DNA-binding domain.



In this comprehensive analysis, mutations in tumor p53 induce strong, polyclonal autoantibodies with broadly reactive epitope specificity.
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Benjamin A
BA
Katchman
Biochemistry and Molecular Biology I Department, Complutense University, Madrid, Spain.
Rodrigo
R
Barderas
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Rizwan
R
Alam
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Diego
D
Chowell
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Matthew S
MS
Field
Department of Surgery, University of California, San Francisco, CA, USA.
Laura J
LJ
Esserman
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Garrick
G
Wallstrom
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Joshua
J
LaBaer
Department of Gynecology and Reproductive Biology, Brigham and Women's Hospital, Boston, MA.
Daniel W
DW
Cramer
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, USA.
Michael A
MA
Hollingsworth
Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA.
Karen S
KS
Anderson
D000918:Antibody Specificity; D001323:Autoantibodies / Q000097:blood / Q000276:immunology; D001943:Breast Neoplasms / Q000097:blood / Q000235:genetics / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D005260:Female; D006801:Humans; D009154:Mutation; D010051:Ovarian Neoplasms / Q000097:blood / Q000235:genetics / Q000276:immunology*; D010190:Pancreatic Neoplasms / Q000097:blood / Q000235:genetics / Q000276:immunology*; D040901:Proteomics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism
D001323:Autoantibodies; D000939:Epitopes; D016159:Tumor Suppressor Protein p53
Antibody mapping; Autoantibody; Cancer; Protein array; p53