Natural killer cells infiltrating colorectal cancer and MHC class I expression

5-Fluorouracil and Interleukin-2 Immunochemotherapy Enhances Immunogenicity of Non-Small Cell Lung Cancer A549 Cells through Upregulation of NKG2D Ligands

“…Notably, tumor cells often exhibit low MHC expression, thereby escaping from CTL-mediated immunologic surveillance (Sandel et al, 2005). Bone marrow-derived NK cells are an important effector population required to eliminate malignant tumor cells in the absence of MHC expression or the presence of mutant MHC molecules (Siddle et al, 2013;Kärre, 2002).…”

Immunosurveillance is active in colorectal cancer as downregulation but not complete loss of MHC class I expression correlates with a poor prognosis

“…Corroborating evidence for this hypothesis is provided by the finding that primary colorectal tumors display sparse NK-cell infiltration compared to the presence of tumorinfiltrating CD81 T cells, suggesting that the survival benefit observed in tumors with total loss of MHC class I expression may be due to clearance of metastasizing tumor cells by NK cells in the systemic circulation and the liver rather than the primary tumor itself. 20 Despite this, if early stage tumors become relatively resistant to immune attack due to the selective downregulation of MHC class I, then recurrence of the disease after surgical treatment will be more likely. These results are therefore particularly pertinent to the development of immunotherapeutic strategies for colorectal cancer, suggesting that early stage patients who have downregulated MHC class I expression may derive greater benefit from adjuvant chemotherapy, as their immune response is unlikely to remove any circulating tumor cells after surgery.…”

Invasive front of colorectal cancer: Dynamic interface ofpro-/anti-tumor factors

“…Evidence is accumulating which suggests that the presence of dendritic cells may be of significant benefit to patients with colorectal cancer [82] . Using immunohistochemistry for CD83, Suzuki et al [83] described the presence of mature dendritic cells at the invasive margin of cancer stroma and demonstrated by light and electron microscopy their formation into clusters with lymphocytes, the majority of which were CD45RO+ T cells.…”