Although it is increasingly recognised that Treg represent a heterogeneous T-cell population which may include FoxP3- cells, FoxP3 expression is still considered the most appropriate single marker for the detection of Treg in situ and most studies assessing the prognostic relevance of Treg in human cancers rest on the analysis of FoxP3+ cells (e.g., Gobert et al.)[7]. Here, FOXP3 is linked to cancer.