Figure 2.

Mechanism of chemoradiation–immunotherapy combination in esophageal cancer. Chemoradiation can directly lead to the death of cancer cells by apoptosis, necrosis, and autophagy, promoting the release of tumor-specific antigens by tumor cells and increasing the chances of immune cells finding cancer cells. Chemoradiation can also directly destroy the DNA of cells, causing cancer cells to produce neoantigens and triggering an immune response. In addition, chemoradiation can upregulate the expression of tumor MHC-I that can better present tumor-specific antigens and enhance tumor visibility by cytotoxic T cells. Radiotherapy can modulate the tumor microenvironment, increase the tumor microenvironment, and promote the migration of cytotoxic T cells to the tumor. Radiotherapy also upregulates the PD-L1 expression level on the cancer-cell surface, enhancing the therapeutic effect of PD-L1 antibodies.