The purpose of this study were to assess the maximal tolerated dose, safety, and immunological response induced by the intradermal(i.d) administration of dendritic cells(DC) vaccine in which tumor lysates were loaded by electroporation and pulse to non-small-cell lung cancer(NSCLC) patients.
Fifteen patients with stage IIIB or IV NSCLC who failed all the conventional methods of treatments were enrolled in cohorts that received 3, 6, 12 × 106 DC i.d. every 2 weeks for three vaccines. Autologous DC were loaded tumor lysate by electroporation and pulse. Peripheral blood mononuclear cells(PBMC) harvested 1 month after the last immunization were compared with pretreatment PBMC for immunologic response. After verification of tolerability, the dose were given 2 more times monthly to investigate immunologic response and tumor response.
Tolerance evaluation was conducted with total of 11/15(73%) patients. The maximum dosage of 12 × 106 proved to be safe. There were no grade 3 or 4 toxicities associated with the vaccines. Five patients of nine available patients, the vaccine resulted in increased interferon-gamma production by CD8+ cells after tumor lysate exposure. In three patients tumor regressed partially, but new lesions developed simultaneously may be with different antigenecity.
The administration of tumor lysate loaded DC by electroporation and pulse is nontoxic and capable of inducing immunological response to tumor antigen.
To overcome the paradoxical response, earlier treatment before massive mestasis; and to improve the clinical response much more doses of DC may improve the results.
Choon-Hee Son, No Financial Disclosure Information; No Product/Research Disclosure Information