Detection of novel cancer-testis antigen-specific T-cell responses in TIL, regional lymph nodes, and PBL in patients with esophageal squamous cell carcinoma

Cancer Sci. 2008 Jul;99(7):1448-54. doi: 10.1111/j.1349-7006.2008.00844.x. Epub 2008 Apr 30.

Abstract

We recently identified three HLA-A2402-restricted epitope peptides derived from cancer-testis antigens (CTA), TTK protein kinase (TTK), lymphocyte antigen 6 complex locus K (LY6K), and insulin-like growth factor (IGF)-II mRNA binding protein 3 (IMP-3) for the development of immunotherapies against esophageal squamous cell carcinoma (ESCC). In order to evaluate their immunotherapeutic potential in ESCC patients, we estimated by ELISPOT assay the TTK-, LY6K-, or IMP-3-specific T-cell immune responses in tumor-infiltrating lymphocytes (TIL), regional lymph node lymphocytes (RLNL), and peripheral blood lymphocytes (PBL) expanded from 20HLA-A2402 (+) ESCC patients, and correlated their immune activity with the expression levels of TTK, LY6K, and IMP-3, and MHC class I in the tumors. Induction of TTK-antigen specific T-cell response in TIL to the peptide-pulsed target cells was detected in 14 out of 20 (70%) cases, while LY6K or IMP-3 specific T-cell activity was observed in 11 of 20 (55%) or in eight of 20 (40%) cases, respectively. Furthermore, T-cell activity in RLNL and PBL was detectable in the similar proportion of the 20 ESCC patients. Interestingly, CTA-specific T-cell immune response was found in 13 of 14 (93%) TIL obtained from ESCC tumors with strong MHC class I expression, while it could be observed only in two of six (33%) TIL from ESCC tumors with weak MHC class I expression. These results strongly suggest the pre-existence of specific T-cell responses to HLA-A24-restricted epitope peptides from TTK, LY6K, and IMP-3 in ESCC patients. Monitoring antigen-specific T-cell responses, as well as the expression levels of MHC class I and epitope CTA in tumors, should be a selection index for application of cancer vaccine therapies to the patients who are likely to show good immune response.

MeSH terms

  • Aged
  • Antigens, Ly / analysis
  • Antigens, Ly / immunology*
  • Carcinoma, Squamous Cell / immunology*
  • Cell Cycle Proteins / analysis
  • Cell Cycle Proteins / immunology*
  • Cell Line
  • Esophageal Neoplasms / immunology*
  • GPI-Linked Proteins
  • Histocompatibility Antigens Class I / analysis
  • Humans
  • Lymph Nodes / immunology*
  • Lymphocytes, Tumor-Infiltrating / immunology*
  • Male
  • Middle Aged
  • Neoplasm Proteins / analysis
  • Neoplasm Proteins / immunology*
  • Protein-Serine-Threonine Kinases / analysis
  • Protein-Serine-Threonine Kinases / immunology*
  • Protein-Tyrosine Kinases
  • RNA-Binding Proteins / analysis
  • RNA-Binding Proteins / immunology*

Substances

  • Antigens, Ly
  • Cell Cycle Proteins
  • GPI-Linked Proteins
  • Histocompatibility Antigens Class I
  • IGF2BP3 protein, human
  • LY6K protein, human
  • Neoplasm Proteins
  • RNA-Binding Proteins
  • Protein-Tyrosine Kinases
  • Protein-Serine-Threonine Kinases
  • TTK protein, human