Send to

Choose Destination
Bull Cancer. 2011 Feb;98(2):E25-31. doi: 10.1684/bdc.2010.1294.

Mechanisms of tumor escape from the immune system: adenosine-producing Treg, exosomes and tumor-associated TLRs.

Author information

University of Pittsburgh, Cancer Institute, PA 15213, USA.


Human tumors utilize many different mechanisms of immunosuppression to prevent immune cells from exercising their antitumor activities. These mechanisms, which enable the tumor to escape from the host immune system and to progress, are being intensively investigated in hope of finding therapeutically safe and effective inhibitors able to counteract tumor-induced immunosuppression. Three of more recently discovered tumor-related suppression mechanisms, i.e. accumulations of adenosine-producing regulatory T-cells (Treg) in the tumor microenvironment, release by tumors of suppressive microvesicles (TMV) and expression of toll-like receptors (TLR) on the tumor cell surface, are described in this review. All contribute in a varying degree to creating a milieu favorable for the tumor and unfavorable for immune effector cells. Tumor escape has been a major problem in cancer immunotherapy and it has been held responsible for the failure of many immune interventions in cancer. For this reason, it is important to study and understand the various suppressive pathways human tumors utilize. Future antitumor immunotherapies are likely to include inhibitors of tumor-induced suppression with the goal of restoring antitumor immune responses in patients with cancer.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for John Libbey Eurotext
Loading ...
Support Center