Forkhead box p3 (Foxp3<sup>+</sup>) regulatory T cells (Tregs) are abundant in the tumor microenvironment where they dampen functions of host anti-tumor immunity and promote cancer progression.
Regulatory T (Treg) cells expressing the transcription factor Foxp3 are critical for the prevention of autoimmunity and the suppression of anti-tumor immunity.
Regulatory T cells (Tregs) are CD4+ T cells that express CD25 and transcription factor Forkhead box P3 (FOXP3), and Tregs play a central role in regulation of tumor immunity.
Therefore, it is crucial to investigate the "true Treg (eTreg)" population, rather than the entire FOXP3 population, with regards to their effect on tumor immunity.