Furthermore, Wang et al (2006) recently showed that IFNγ is important for the conversion of CD4+CD25−FOXP3− cells to CD4+CD25+FOXP3+ Tregs, thus it is possible that those CD4+FOXP3+ Tregs in MCA-induced tumours are derived from CD4+CD25−FOXP3− cells by a process, which is IFNγ dependent. Here, CD4 is linked to neoplasm.