Immune Netw.  2009 Dec;9(6):209-235. 10.4110/in.2009.9.6.209.

The Role of Regulatory T Cells in Cancer

• Ha TY

• KMID: 2150650
• DOI: http://doi.org/10.4110/in.2009.9.6.209

Abstract

There has been an explosion of literature focusing on the role of regulatory T (Treg) cells in cancer immunity. It is becoming increasingly clear that Treg cells play an active and significant role in the progression of cancer, and have an important role in suppressing tumor-specific immunity. Thus, there is a clear rationale for developing clinical strategies to diminish their regulatory influences, with the ultimate goal of augmenting antitimor immunity. Therefore, manipulation of Treg cells represent new strategies for cancer treatment. In this Review, I will summarize and review the explosive recent studies demonstrating that Treg cells are increased in patients with malignancies and restoration of antitumor immunity in mice and humans by depletion or reduction of Treg cells. In addition, I will discuss both the prognostic value of Treg cells in tumor progression in tumor-bearing hosts and the rationale for strategies for therapeutic vaccination and immunotherapeutic targeting of Treg cells with drugs and microRNA.

Keyword

Cancer; Regulatory T cells; Suppressor T cells; MicroRNA; Immunotherapy

MeSH Terms

Animals
Explosions
Humans
Immunotherapy
Mice
MicroRNAs
T-Lymphocytes, Regulatory
Vaccination
MicroRNAs

Figure

• 

  Figure 1 Tumor-mediated generation of regulatory T (Treg) cells and the effect on the tumor microenvironment. Tumor cells induce the generation of Treg cells through both cell contact-dependent and cell contact-independent mechanisms. Soluble protein such as TGFβ produced by tumor cells promote the proliferation of Treg cells and induce the conversion of naive CD4+CD25- T cells into Treg cells. Tumor cells also express costimulatory molecules such as CD80/CD86 or CD70 and interact with naive T cells to convert these naive T cells into Treg cells. The increased numbers of Treg cells inhibit the NK cells, CD4+ T cells, CD8+T cells and the other cells and contribute to the progression of tumors.

• 

  Figure 2 Therapeutic targeting of regulatory T cells. The patients with cancer might be subjected to traditional tumor therapy, conventional immunotherapy and/or novel tumor immunotherapy. To attain more effective, reliable and consistent clinical efficacy, it might be essential to apply combinatorial therapy. APC, antigen presenting cell; CTLA4, cytotoxic T-lymphocytes-associated antigen 4; PD1, programmed cell death; COX2, cyclooxygenase.

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