CD4 and breast cancer: Finally, our group has demonstrated that this effect of tumors upon DCs does not depend on the continuous presence of neoplastic cells, since Mo-DCs from breast cancer patients even when differentiated in vitro and, therefore, away from the direct tumor influence, are poor T-cell stimulators and biased to induce CD4+CD25+Foxp3+ regulatory T cells when cocultured with naïve CD4+CD45RA+ lymphocytes (Figure 2).