Educational Review Cellular and Biological Therapies of Gastrointestinal Tumors: Overview of Clinical Trials

Abstract

Because of the high relapse rate of resected gastrointestinal malignancies and the modest responses of metastatic disease to currently available therapies, biologic agents that harness host-tumor immunologic interactions have received increased attention. Based on promising preclinical data, current clinical trials in cellular and biologic therapies are evaluating the safety and efficacy of passive immunotherapy with tumor-reactive lymphocytes activated ex vivo and active immunotherapy with peptide, viral vector, and cellular vaccines. This review will describe the background, rationale, and experimental approach of these clinical trials. Although equally promising, antibodies, gene therapies, and antiangiogenic strategies will not be discussed.

Induction of Tumor-Specific Cytotoxic T Lymphocytes in Cancer Patients by Autologous Tumor RNA-Transfected Dendritic Cells

“…[1][2][3] Because T cells recognize antigens as peptide epitopes bound in the groove of major histocompatibility complex (MHC) molecules, 4 experimental attempts to induce T-cell responses have included immunization with MHC-restricted, tumor antigenassociated peptides, [5][6][7] and proteins representing these tumor-associated antigens along with an adjuvant. 8,9 An exciting approach is the use of a potent cellular adjuvant, the antigen-presenting dendritic cell (DC), loaded with the antigen of interest.…”