Soluble NKG2D ligands: prevalence, release, and functional impact
Helmut Rainer Salih1, Stefan Holdenrieder, Alexander Steinle
1Department of Internal Medicine II, Eberhard-Karls-University, Tuebingen, Germany. alexander.steinle@uni-tuebingen.de
Summary
Natural Killer (NK) cells fight tumors, but cancers release NKG2D ligands (NKG2DL) to evade them. This review explores soluble NKG2DL (sNKG2DL) in cancer and non-cancer conditions, and their clinical relevance.
Area of Science:
- Immunology
- Cancer Biology
Background:
- Natural Killer (NK) cells are crucial for eliminating malignant cells.
- Tumor-expressed NKG2D ligands (NKG2DL) promote NK cell anti-tumor responses.
- Established tumors can subvert NK cell immunosurveillance by releasing NKG2DL.
Purpose of the Study:
- To review and discuss the prevalence, release, and functional impact of soluble NKG2DL (sNKG2DL).
- To explore the potential clinical value of sNKG2DL in cancer and non-malignant conditions.
Main Methods:
- Literature review of existing data on sNKG2DL.
- Analysis of studies reporting NKG2DL release in various human tumor entities.
- Examination of findings on elevated sNKG2DL in non-malignant conditions.
Main Results:
- NKG2DL release is observed across diverse human tumor types.
- Elevated sNKG2DL levels are also found in non-malignant conditions.
- The functional implications of sNKG2DL in non-malignant settings require further clarification.
Conclusions:
- Soluble NKG2DL play a role in subverting NKG2D-mediated tumor immunity.
- Understanding sNKG2DL is critical for developing novel cancer immunotherapies.
- Further research is needed to elucidate the full clinical significance of sNKG2DL.
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