Dendritic Cell-Tumor Cell Fusion Vaccines

Breast Cancer Vaccines: Disappointing or Promising?

Breast cancer has become the most commonly diagnosed cancer globally. The relapse and metastasis of breast cancer remain a great challenge despite advances in chemotherapy, endocrine therapy, and HER2 targeted therapy in the past decades. Innovative therapeutic strategies are still critically in need. Cancer vaccine is an attractive option as it aims to induce a durable immunologic response to eradicate tumor cells. Different types of breast cancer vaccines have been evaluated in clinical trials, but none has led to significant benefits. Despite the disappointing results at present, new promise from the latest study indicates the possibility of applying vaccines in combination with anti-HER2 monoclonal antibodies or immune checkpoint blockade. This review summarizes the principles and mechanisms underlying breast cancer vaccines, recapitulates the type and administration routes of vaccine, reviews the current results of relevant clinical trials, and addresses the potential reasons for the setbacks and future directions to explore.

Immunological suppression of head and neck carcinoma by dendritic cell tumor fusion vaccine

The successful treatment of cancer with dendritic cell (DC) tumor vaccine is highly dependent on the efficacy of antigen presentation and T cell activation. In the present study, a novel vaccine of DCs fused with autologous tumor cells was introduced, which had a marked ability to suppress head and neck carcinoma. DCs generated from the bone marrow of mice were fused with an autologous tumor cell line using polyethylene glycol (PEG). To observe the fused cells, confocal microscopy and FACS analysis were performed. Subsequently, the activation and proliferation of T cells, as well as animal experiments, were examined. The efficiency of DC/tumor fusion was 18.03% and T cells were well-activated by the hybrids. The volumes of tumors on the tumor-bearing mice were controlled, survival time of tumor-bearing mice was prolonged and the level of IFN-γ in serum was significantly increased compared with the control group and lysate-pulsed DC group. The results indicate that the DC/tumor fusion vaccine appears to be more effective than DCs pulsed with tumor lysate for the treatment of head and neck carcinoma, which may be useful in future clinical studies.

Dendritic/tumor fusion cells as cancer vaccines

A promising cancer vaccine involves the fusion of dendritic cells (DCs) with tumor cells such that a broad array of tumor antigens are presented in the context of DC-mediated costimulation and stimulatory cytokines. In diverse animal models, vaccination with DC/tumor fusions results in protection from an otherwise lethal challenge of tumor cells and eradication of established disease. In phase I clinical studies, vaccination with DC/tumor fusions was well tolerated, and induced immunologic responses in the majority of patients and clinical responses in a subset. Vaccine efficacy may be blunted by the immunosuppressive milieu characteristic of patients with malignancy, including the increased presence of regulatory T cells, and inhibitory pathways such as the PD-1/PDL-1 pathway. A current focus of research interest lies in enhancing response to cancer vaccines, by combining vaccination with tumor cytoreduction, regulatory T-cell depletion, and blockade of critical inhibitory pathways.