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Identification of class I MHC-associated phosphopeptides as targets for cancer immunotherapy.

ABSTRACT: Alterations in phosphorylation of cellular proteins are a hallmark of malignant transformation. Degradation of these phosphoproteins could generate cancer-specific class I MHC-associated phosphopeptides recognizable by CD8+ T lymphocytes. In a comparative analysis of phosphopeptides presented on the surface of melanoma, ovarian carcinoma, and B lymphoblastoid cells, we find 5 of 36 that are restricted to the solid tumors and common to both cancers. Differential presentation of these peptides can result from differential phosphorylation of the source proteins. Recognition of the peptides on cancer cells by phosphopeptide-specific CD8+ T lymphocytes validates the potential of these phosphopeptides as immunotherapeutic targets.

SUBMITTER: Zarling AL

PROVIDER: S-EPMC1595446 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Identification of class I MHC-associated phosphopeptides as targets for cancer immunotherapy.

Zarling Angela L AL Polefrone Joy M JM Evans Anne M AM Mikesh Leann M LM Shabanowitz Jeffrey J Lewis Sarah T ST Engelhard Victor H VH Hunt Donald F DF

Proceedings of the National Academy of Sciences of the United States of America 20060925 40

Alterations in phosphorylation of cellular proteins are a hallmark of malignant transformation. Degradation of these phosphoproteins could generate cancer-specific class I MHC-associated phosphopeptides recognizable by CD8+ T lymphocytes. In a comparative analysis of phosphopeptides presented on the surface of melanoma, ovarian carcinoma, and B lymphoblastoid cells, we find 5 of 36 that are restricted to the solid tumors and common to both cancers. Differential presentation of these peptides can ...[more]

PMID: 17001009

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