The general outline of this study was to evaluate the in vivo effects of the recombinant WW2/WW3 domains fused to TAT peptide (a cell-penetrating peptide that renders the whole protein capable of penetrating into cells in a receptor-independent fashion) on the ratio of spleen CD4+CD25+/CD4+ cell and tumor growth in 4T1 tumor-bearing mice. This evidence concerns the gene CD4 and neoplasm.