Cancer Vaccines Show Promise in Recent Research

Strategic Insights -

Recent studies published in Clinical Immunology and the Journal of Clinical Immunology have demonstrated the efficacy of cancer vaccines in stimulating the body's immune system to fight cancer cells. Researchers at Boston and Harvard Universities have successfully fused human dendritic cells with tumor cells, creating a potent stimulator of autologous T cells. In another study, scientists at the University of Washington found that immunization with a HER-2/neu peptide-based vaccine resulted in the generation of HER-2/neu-specific antibody immunity in 60% of patients. Additionally, a Phase I study conducted at Cedars-Sinai Medical Center found that vaccination with tumor lysate-pulsed dendritic cells elicits antigen-specific, cytotoxic T-cells in patients with malignant glioma. These findings suggest that cancer vaccines may be a promising approach for treating various types of cancer.

Key Takeaways:

  • Researchers at Boston and Harvard Universities have successfully fused human dendritic cells with tumor cells, creating a potent stimulator of autologous T cells.
  • Immunization with a HER-2/neu peptide-based vaccine resulted in the generation of HER-2/neu-specific antibody immunity in 60% of patients.
  • Vaccination with tumor lysate-pulsed dendritic cells elicits antigen-specific, cytotoxic T-cells in patients with malignant glioma.
  • The median survival for patients with recurrent glioblastoma multiforme in the study was 133 weeks.
  • Humoral intramolecular epitope-spreading within the HER-2/neu protein occurred in 49% of immunized patients, and intermolecular epitope-spreading to p53 was evident in 20% of vaccinated patients.
  • Six of 10 patients demonstrated robust systemic cytotoxicity as demonstrated by IFN-gamma expression by peripheral blood mononuclear cells in response to tumor lysate after vaccination.
  • A significant CD8+ T-cell infiltrate was noted intratumorally in three of six patients who underwent re-operation.

Statistics:

  • 60% of patients developed HER-2/neu IgG-specific antibody responses to at least one peptide included in their vaccine.
  • 29% of patients developed IgG immunity to the native HER-2/neu protein after peptide immunization.
  • 49% of immunized patients experienced humoral intramolecular epitope-spreading within the HER-2/neu protein.
  • 20% of vaccinated patients demonstrated intermolecular epitope-spreading to p53.
  • 133 weeks (median survival for patients with recurrent glioblastoma multiforme).
  • 10 patients (60%) developed robust systemic cytotoxicity as demonstrated by IFN-gamma expression by peripheral blood mononuclear cells in response to tumor lysate after vaccination.
  • 3 of 6 patients (50%) demonstrated a significant CD8+ T-cell infiltrate intratumorally.

Sources:

  • Koido, S., et al. (2004). Dendritic cells fused with human cancer cells: morphology, antigen expression, and T cell stimulation. Clin Immunol, 113(3), 261-269.
  • Disis, M. L., et al. (2004). Humoral epitope-spreading following immunization with a HER-2/neu peptide-based vaccine in cancer patients. J Clin Immunol, 24(5), 571-578.
  • Yu, J. S., et al. (2004). Vaccination with tumor lysate-pulsed dendritic cells elicits antigen-specific, cytotoxic T-cells in patients with malignant glioma. Cancer Res, 64(14), 4973-4979.