Dendritic Cells in Esophageal Adenocarcinoma: The Currently Available Information and Possibilities to use Dendritic Cells for Immunotherapeutic Approaches

Esophageal adenocarcinoma (EAC) is the second frequent cancer of the esophagus. Barrett's esophagus (BE) takes precedence over EAC. BE is a metaplastic change of the stratified squamous epithelium to the intestinal columnar epithelium due to the acidic gastrointestinal reflux. Further, the disease takes the hyperplastic stage followed by EAC. An initial immune response is an essential reaction of a body to an occurrence of alien/modified cells to be removed. It has been appreciated that an inflammatory reaction occurs in the early stages of EAC or even in BE. Dendritic cells (DCs) play a key role in a frontier of an immune response due to their advanced ability to recognize foreign antigens and mobilize naive T cells to effectors. However, in a cancer condition, tumor-delivered immunosuppression occurs in a variety of mechanisms that alter/switch the functionality of DCs from immune activating to immune suppressive cells. In this brief review, we consider tumor-induced paths of a capacity of tumor cells to down-regulate DCs, with a focus on EAC, and also discuss a possibility to use DCs for immunotherapeutic approaches. Indeed, DCs represent a promising tool for developing new immunotherapeutic approaches for cancer treatment including EAC. It has been reported to achieve effective DC-mediated immune responses by raising anti-tumor cytotoxic T cell responses against multiple cancer antigens through loading DCs with total tumor RNA. However, more studies should be performed in order to understand a precise role in tumor-induced mechanisms of DC suppression in BE/EAC. Likely, these mechanisms should involve general carcinogenic and EAC-specific pathways.