T-Regulatory Cells: Key Players in Tumor Immune Escape and Angiogenesis

Ovarian Cancer Research Center, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Cancer Research (Impact Factor: 9.33). 05/2012; 72(9):2162-71. DOI: 10.1158/0008-5472.CAN-11-3687
Source: PubMed


T-regulatory cells (Tregs) are found infiltrating tumors in a vast array of tumor types, and tumor-infiltrating Tregs are often associated with a poor clinical outcome. Tregs are potent immunosuppressive cells of the immune system that promote progression of cancer through their ability to limit antitumor immunity and promote angiogenesis. Here, we discuss the ways in which Tregs suppress the antitumor immune response and elaborate on our recent discovery that Tregs make significant direct contributions to tumor angiogenesis. Further, we highlight several current therapies aimed at eliminating Tregs in cancer patients. Given the multifaceted role of Tregs in cancer, a greater understanding of their functions will ultimately strengthen future therapies.

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Available from: Andrea Facciabene, Oct 27, 2014

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Article: T-Regulatory Cells: Key Players in Tumor Immune Escape and Angiogenesis

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    • "All of these mechanisms suggest that the enlarged Treg population consists of a mixture of both nTreg (thymic and peripheral) as well as pTreg. Importantly, elevated Treg numbers and their highly suppressive function not only help tumors to evade from a productive immune surveillance (Facciabene et al., 2012), but also represent major hurdles towards successful immunotherapy (Curiel et al., 2004; Fehervari and Sakaguchi, 2005; Jacobs et al., 2012). Thus, Treg may provide an ideal target to increase cancer immune-surveillance and their initial description refuelled the hope of tumor-immunologists that cancer vaccination may be re-vitalized after years of frustrating research almost exclusively producing negative results. "
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    • "We found that administration of GA-A significantly suppressed metastasis of EL4 lymphoma cells to the liver, which correlated with improved survival. While Tregs are often associated with a poor clinical outcome [Facciabene et al., 2012], this study did not find any significant changes in Treg cells in vehicle versus GA-A treated mice. By contrast, we have found GA-A treatment attenuates EL4 tumor growth and metastasis by a marked inhibition of MDSC populations in the host, which could be regulated via the STAT3 pathway [Kujawski et al., 2008]. "
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